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Full text of "World Mangrove Atlas"

World 



MANGROVE 




ATLAS 



Editors: 

Mark Spalding, Francois Blasco and Colin Field 



» • ,-.v^% 



World Mangrove Atlas 

The World Mangrove Atlas is the first significant attempt to 
provide an overview of the distribution of mangroves 
worldwide. Mapped data have been gathered fi-om a wide 
range of sources and have been synthesised into a series of 
twenty-five regional maps. Related texts describe the species, 
areal extent and other summary information on the 
currently known status of mangroves in each country. This 
is the first time that such data have been gathered into a 
single volume. All data are referenced back to an original 
source. For people interested in the extent and dynamics of 
mangroves, this atlas provides a well documented foundation 
firom which to start their explorations. 

A number of case studies demonstrate what can be achieved 
using greater resolution and much more detailed 
investigation. The case studies show mangroves growing in 
very different conditions such as estuaries, deltas, lagoons, 
wet tropical coasts and arid coasts. They illustrate a range of 
different mapping techniques and provide detail on some of 
the issues threatening mangroves worldwide. Together with 
introductory chapters covering mapping techniques and 
mangrove phytogeography, the result is a wide-ranging but 
highly informative reference work. 

Mangrove ecosystems are of great environmental and 
economic importance. However, mangrove forests in many 
countries are threatened and vast areas have already 
disappeared. The World Mangrove Atlas presents a baseline 
inventory of mangroves at the end of the twentieth century. 
It is intended for use by scientists, politicians, planners, 
conservationists and others, who have an interest in the 
current status and future of mangroves. 

The World Mangrove Atlas is part of a trilogy being produced 
by the International Society for Mangrove Ecosystems and 
the International Tropical Timber Organization to promote 
awareness of the importance of mangroves. The other two 
parts of the trilogy are: Journey Amongst Mangroves and 
Restoration oj Mangrove Ecosystems. 



About the Editors 

Mark Spalding has a degree in Natural Sciences fiom the 
University of Cambridge. He is currently the Marine Research 
Officer at the World Conservation Monitoring Centre, 
working largely on biodiversity mapping of both mangrove 
forests and coral reefs. In parallel with these activities he is 
undertaking a Ph.D. in biodiversity mapping in the 
Department of Geography, University of Cambridge. 

Francois Blasco has a doctorate in tropical ecology from the 
Paul Sabatier University in Toulouse. He has a considerable 
experience of mangrove ecosystems and on the digital 
processing and analysis of satellite data. He is currently 
Director of the Laboratory for Terrestrial Ecology in 
Toulouse and Research Director at the National Council for 
Scientific Research (CNRS), Paris. 

Colin Field has a degree in physics from the University of 
Reading and a Ph.D. in biophysics and physiology firom the 
University of the West Indies. He is currently Emeritus 
Professor at the University of Technology in Sydney He is 
overall coordinator of the ISME-ITTO mangrove project 
of which the atlas is one part. 



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http://www.archive.org/details/worldmangroveatl97spal 



WORLD MANGROVE ATLAS 



World Mangrove Atlas 



Editors 
Mark Spalding, Fran9ois Blasco and Colin Field 



The International Society for Mangrove Ecosystems 

The World Conservation Monitoring, Centre 

The International Tropical Timber Organization 



First published in 1997 by: The International Society for Mangrove Ecosystems (ISME). 




Copyright: 



1997. The International Society for Mangrove Ecosystems. 

This pubhcation may be produced in whole or in part and in any form for education or non-profit 
uses, without special permission from the copyright holder, provided acknowledgement of the source 
is made. ISME would appreciate receiving a copy of any publication which uses this pubhcation as a 
source. 

No use of this publication may be made for resale or other commercial purpose without prior 
permission of ISME. 



Citation: 



Spalding, M.D , Blasco, E and Field, CD. (Eds). 1997. World Mangrove Alias. The International Society 
for Mangrove Ecosystems, Okinawa, Japan. 17H pp. 



ISBN: 



4 906584 03 9 



Design and typesetting: 
Cover design: 
Photographs: 



Samara Publishing Luiiited, Samara House, Tresaith, Cardigan SA43 2JG, UK. 

Mandy Bell, Samara Pubhshing Limited, Samara House, Tresaith, Cardigan SA43 2JG, UK. 

Cover: A satellite view of the distribution of the mangroves of the Ranong area (F. Blasco). 

Mangroves south east of Kalabakan, Sabah (R.H. Hughes). 
Part 1 title page: Mangroves on tributary of Merutai River, Sabah (R.H. Hughes). 
Part 2 title page: Mangroves on Pulau Simandalan, Nr Wallace Bay, Sabah (R.H. Hughes). 



Available from: 



The International Society for Mangrove Ecosystems, College of Agriculture, 
University of the Ryukyus, Okinawa 903-01, Japan. 



Production: 



The World Conservation Monitoring Centre (WCMC), Cambridge, UK prepared the maps and 
co-ordinated the production of the atlas. Publication of this atlas was made possible by a generous 
grant of funds from the International Tropical Tmiber Orgamzation (ITTO), Yokohama, Japan. 






\MORLD CONSERVATION 
MONITORING CENTRE 




ITTCr 



Printed by: 



Smith Settle. Otley, West Yorkshire, UK. 



Disclaimer: 



The designations of geographical entities in this report, and the presentation of the material, do not 
imply the expression of any opinion whatsoever on the part of the participating organisations 
concermng the legal status of any country, territory, or area, or of its authorities, or concerning the 
delimitation of its frontiers or boundaries. 

The opinions expressed by the editors in this publication do not necessarily present the views of 
ISME, WCMC or ITTO. 



Contents 



Foreword 7 

Preface 8 

Part 1 World Mangrove Distribution 

1 Introduction ii 

2 The Mapping of Mangroves 14 

3 The Global Distribution of Mangroves 23 
Global Distribution Map Opp. 24 

4 Some Phytogeographical Considerations 27 
Species Distribution Maps 31 

Part 2 Regional Mangrove Distributions 

5 South and Southeast Asia 43 

Case Studies 

Mangroves of the Ganges and Brahmaputra Deltas 47 

The Cauvery Delta (Pichavaram): coastal lagoon mangroves 55 

The mangroves of Balochistan, Pakistan 63 

Estuarine mangroves in Thailand: Ranong 67 

Regional Distribution Maps 

Pakistan, India and Sri Lanka 74 

Continental Southeast Asia 75 

Vietnam, Southern China and Hong Kong 76 

East China, Taiwan andfapan 77 

The Philippines 78 

Sumatra and Peninsular Malaysia 79 

Borneo andfava 80 

Eastern Indonesia 81 



6 Australasia 82 

Regional Distribution Maps 

Western Australia 90 

Eastern Australia 91 

South Pacific Islands 92 

Papua New Guinea and the Solomon Islands 93 

7 The Americas 94 
Case Study 

The mangroves of French Guiana: a dynamic coastal system 103 

Regional Distribution Maps 

Mexico 122 

Central America 123 

Florida, Bahamas and the Greater Antilles 124 

Puerto Rico and the Lesser Antilles 125 

Eastern Venezuela, Trinidad and the Guianas 126 

Northwest South America 127 

Brazil 128 

8 West Africa 129 
Case Studies 

The mangroves of Gabon 135 

TTie riverine mangroves of Gambia 139 

Sahelian mangroves in Sine-Saloum, Senegal 148 

Regional Distribution Maps 

Northwest Africa: Mauritania to Sierra Leone 154 

West Africa: Liberia to Nigeria 155 

Southwest Africa: Nigeria to Angola 156 

9 East Africa and the Middle East 157 
Regional Distribution Maps 

Arabian Peninsula, Red Sea and the Gulf 169 

East Africa: Somalia to Tanzania 170 

Mozamabique, Madagascar and South Africa 171 

Index 173 



Foreword 



The underlying spirit and philosophy of the Inter- 
national Tropical Timber Organization (ITTO), as 
enshrined in the International Tropical Timber Agree- 
ment, IS to strike a balance between utilisation and 
conservation of tropical forests through sustainable 
development. This is clearly stated in the objectives of 
the agreement "to encourage the development of 
national policies aimed at sustainable utilisation and 
conservation of tropical forests and their genetic 
resources, and at maintaining the ecological balance 
in the region concerned". As provided for in the 
Agreement, ITTO goes beyond the narrow com- 
modity focus of tropical timber, to be mvolved in 
conservation and forest management. The aim is to 
ensure the continued production not only of timber 
but also of other vital goods and services from the 
forests. Carefiil analysis of the problems besetting 
tropical forests indicates that only such an approach 
will ensure their survival. 

Tropical forests are vitally needed for their wealth 
of genetic diversity, conservation and environmental 
values. Moreover, large populations in developmg 
countries are dependent upon the forest for timber, 
food and basic essentials. Viable forest industries based 
on sustainable supplies of tropical timber can generate 
social and economic benefits to many developmg 
countries, thereby ensuring the survival of tropical 
forests. Therein lies the hnkage between wise utilisa- 
tion and sustainable management of tropical forest 
resources. 



It is within this background that the ITTO supports 
projects on mangroves. The importance of mangrove 
forests is unquestionable. Mangroves contribute a rich 
genetic diversity, which acts as a buffer zone between 
terrestrial and marine ecosystems. Fringing many 
coastal areas in tropical and sub-tropical countries, the 
mangrove ecosystem is a treasure of valuable goods 
and services which sustain the needs of many coastal 
communities. The wonderful mangrove forests have 
demonstrated to us their vital strategic and ecological 
functions, particularly in sustaining the productivity 
of fish and marine resources. The work now being 
presented in collaboration with the International 
Society for Mangrove Ecosystems (ISME) will improve 
the understanding of the dynamics and distribution 
of mangrove species under a variety of conditions, 
many of which have been modified by human activi- 
ties. This atlas will strengthen the case for remedial 
measures to be taken against the mismanagement and 
abuse of mangrove ecosystems. 

I congratulate the Editors for their pioneering 
effort to produce such a comprehensive and detailed 
World Mangrove Atlas. This atlas will serve as a usefiil 
tool to the general pubhc, educators and other inter- 
ested groups, by enhancing their knowledge of the 
nature and extent of the mangrove ecosystems, in a 
worldwide context. In turn, it will promote efforts to 
save mangrove forests through their conservation and 
sustainable utilisation. 



B.C.Y. Freezailah 

Executive Director 

International Tropical Timber Organization 



Preface 



The origins of this atlas lie in the vision of the 
International Society for Mangrove Ecosystems (ISN4E) 
and the International Tropical Timber Organization 
(ITTO) to present, to as wide an audience as possible, 
information relating to the distribution and current 
status of mangrove ecosystems in our increasingly 
threatened and changing natural environment. It forms 
part of a trilogy being produced as outputs from the 
ISME and ITTO project Manual and World Natural 
Mangrove Atlas No PD 6/93 Rev.2 (F). The other two 
parts are Journey Amongst Mangroves and Restoration of 
Mangrove Ecosystems. The adas draws on the wealth of 
knowledge and experience concerning mangroves 
that has emerged in recent years and in particular it 
has drawn extensively on the expertise and technical 
capabiUty of the World Conservation Monitoring 
Centre (WCMC) in Cambridge, UK and the Institut 
de la Carte Internationale de la Vegetation (ICIV) 
which is supported by the Centre National de la 
Recherche Scientifique and the Universite Paul Saba- 
tier in Toulouse, France. It has also rehed heavily on 
the assistance of a dedicated network of people and 
organisations from around the world, who have first 
hand understanding of the problems of mapping and 
describing mangroves. 

Inevitably, this atlas wUl contain omissions of infor- 
mation and interpretations that not everyone will 
agree with. However, we hope that readers will find 
the information useful and that they will be encour- 
aged to obtain new data that can be made available so 
that the adas can be updated in the future. 

This atlas has benefited from the wisdom of many 
people. It is a pleasure to acknowledge the invaluable 
assistance ofDr Chan Hung Tuck, Malaysia; Professor 
Kazuhiko Ogino, Japan and Mr Mohammed Tahir 
Qureshi, Pakistan. As a group they formed a con- 
sultative committee to assist with the editing and 
production of the atlas. In addition, there are a 
number of people who contributed freely with ideas, 
suggestions, criticism and photographs and without 
whom this book would be much the poorer. 



Appreciation here goes particularly to Professor 
Sanit Aksornkoae, Thailand; Dr Barry Clough, Aus- 
tralia; Professor Phan Nguyen Hong, Vietnam; Mr 
Motohiko Kogo, Japan; Professor Peter Saenger, Aus- 
tralia; Dr N.A. Siddiqi, Bangladesh; Professor Sam 
Snedaker, USA; Dr Arvind Untawale, India; Dr Marta 
Vannucci, India; Dr Richard Luxmoore and Ms Clare 
Billmgton,WCMC,UK;Dr Fromard and DrJ Pontes 
of ICIV, Toulouse, France. 

We are mdebted to Professor Sanga Sabhasri, Presi- 
dent of ISME; Professor Yoshihiro Kohda, Executive 
Secretary of ISME and Dr Shigeyuki Baba, Deputy 
Executive Secretary of ISME who have not only 
generously provided ideas and material for the adas 
but have also given continuous logistic support to the 
project, together with Miss Nozomi Oshiro for her 
helpful contribution in the ISME secretariat. We 
should like to acknowledge the dedicated assistance 
of Ms Mary Edwards who did the GIS work and 
produced the final copies of all of the regional maps. 
Further work and support at WCMC was provided 
by Corinna Ravilious, Ivor Wheeldon and Alastair 
Grenfell. Likewise, thanks are owed to Mrs Marie 
Aizpuru and colleagues who undertook much of the 
work in preparing the maps for the case studies. We 
should also like to recognise the assistance of the 
University of Technology, Sydney, who made their 
facilities available to Cohn Field. In a similar manner 
the Department of Geography, University of Cam- 
bridge provided financial support and other assistance 
to Mark Spalding. Thanks are also due to Mr R. 
Fairclough and the stalFof the Cambridge University 
Library Map Room for all their help in gathering 
maps from their vast collection. 

The funds that supported the production of this 
book came from a generous grant to the Internal 
Society for Mangrove Ecosystems from the Interna- 
tional Tropical Timber Organization and we should 
like to acknowledge the sponsorship of the Japanese 
Government in this project. 



Mark Spalding 

Francois Blasco 

Cohn Field 



Part 1 



World 
Mangrove Distribution 



"V 



Introduction 



As the twentieth century draws to a close there is 
increasing pubhc and scientific concern about the 
future of biological systems on our planet. It is 
becoming recognised that uncontrolled population 
growth, increasing pollution and man-induced 
changes to our climate threaten the welfare of all 
people, not just those in underdeveloped countries. 
There is no agreement on the solutions. There is a 
fierce debate between scientists, economists, social 
planners, politicians, conservationists, developers and 
even theologians, as to the actions that need to be 
taken. There appears to be a lack of conviction and 
willingness on the part of most governments around 
the world to take any action. One of the difficulties 
that firequendy arises is that scientific data relating to 
the environment, and particularly to environmental 
change, are often sparse or unconvincing and therefore 
open to challenge. This World Mangrove Atlas is an 
attempt to provide accurate data and, at least partially, 
to quantify the presence, extent and distribution of a 
distinctive and important coastal ecosystem. 

Mangroves 

Mangrove trees and shrubs (the term also includes 
ferns and palms) are a common sight on mudflats and 
banks of tropical and subtropical rivers and coastlines 
in many parts of the world. They stand with their roots 
in salt water and they are regularly subject to the 
influence of tides. As such they are a special form of 
vegetation existing at the boundary of two environ- 
ments. They are predominantly found in the tropics. 
The species of plants known as mangroves belong to 
a vnde variety of plant families. The common char- 
acteristic which they all possess is tolerance to salt and 
brackish v^^aters. Mangroves have evolved a variety of 
survival and reproductive strategies to deal with their 
muddy, shifting, saline environment. Some seventy 
species of mangrove plants are recognised from 
various regions of the world, with the highest con- 
centrations of species being found in Southeast Asia 
and Australia. More than forty percent of the esti- 
mated eighteen million hectares of mangrove forest 
in the world occur in Asia. Some of the largest 
mangrove forests are found in Indonesia, Brazil and 
the Sundarbans of India and Bangladesh. 

Mangroves support a complex aquatic food web 
and provide a unique habitat for a variety of animals. 



They supply a number of natural resources, while the 
waters surrounding the mangroves are a rich source 
of fish and shellfish. The presence of mangroves in 
some places acts as a stabihsing factor for the river 
banks and coasthne. Mangroves can also play an 
important role in the functioning of adjacent eco- 
systems, including terrestrial wetlands, saltmarshes, 
seagrass beds and coral reefs. 

Man and mangroves 

In regions with continuous high temperatures, pro- 
lific rainfall and the appropriate terrain, mangroves 
have prospered. Productive mangrove forests have 
evolved and this rich resource has been widely used 
by coastal people of the tropics for thousands of years. 
Many human communities have a traditional de- 
pendence on mangroves for their survival and a wide 
range of natural products from the mangroves and 
their surrounding waters are utilised. Mangroves are 
used, among other things, to supply building material, 
firewood, charcoal, food and medicine. 

A balance exists between the complex biological 
system, which the mangrove forests represent, and the 
local people who exploit the system without destroy- 
ing it. Historically, human pressure on the mangroves 
was hmited: all but a few subsistence populations saw 
mangrove areas as inhospitable, unhealthy and dan- 
gerous. They were not easy places to penetrate except 
by small boat and few communities of people actually 
hved within the mangrove forests. 

In recent years, the pressures of increasing popu- 
lation, food production and industrial and urban 
development have led to a significant proportion of 
the world's mangrove resource being destroyed. As 
human populations have risen, the shortage of pro- 
ductive land in developing countries has led to the 
clearance of many areas for agricultural purposes or 
for the provision offish and shrimp ponds for com- 
mercial production. Much of this reclaimed land has 
proved unsuitable for agriculture or aquaculture and 
today it lies derehct. Mangroves have also been 
logged for timber, fijelwood and charcoal production, 
chipped for paper production and destroyed to pro- 
vide land for the construction of mines, ports, tourist 
resorts and housing. The exploitation of mangrove 
forests for short term gain has usually been irre- 
versibly destructive. 



12 



World Mangrove Atlas 



The dilemma 

Twenty years ago, mangroves were generally consid- 
ered as waste lands with little intrinsic value and their 
destruction was encouraged by governments and 
planners. This attitude did little to ensure productive 
and sustainable use of the mangrove ecosystem. Such 
attitudes still exist today and mangroves are being 
cleared around the world without much thought 
being given as to whether this is the best way to 
manage a productive and economically valuable re- 
source. 

The dilemma is how to convince governments and 
developers that mangroves are a valuable resource and 
to persuade them to adopt best practices when decid- 
ing on the utilisation of mangrove land. Mangroves 
can be economically and ecologically important and 
common sense dictates that their use should be man- 
aged carefully. Short term schemes and attempts to 
produce quick profits all too often lead to long term 
disasters. 

Towards a solution 

In the early 1970s scientific interest in mangrove 
ecology began to shift from a long established 
academic investigation of these curious salt-adapted 
collections of plants and animals to include work 
relating to the more immediate problem of their 
rapidly increasing rates of disappearance. RoUet (1981) 
compiled a bibliography of mangrove literature that 
cited more than 6,000 references to research reports 
and journal articles for the period 1600-1975. A 
number of recent texts on mangroves are available 
which give an overview of mangrove ecology and 
mangrove management, such as Tomlinson (1986), 
Hutchings and Saenger (1987), Field and Dartnall 
(1 987) , Robertson and Alongi (1 992) , Field (1 995 and 
1996). 

The wastefiil destruction of vast areas of mangrove 
around the world persuaded a concerned scientific 
community to ask the United Nations Educational, 
Scientific and Cultural Organization (UNESCO) 
and the United Nations Development Programme 
(UNDP) to mount a research and training pro- 
gramme on the biology and value of mangroves in 
Southeast Asia and the Pacific. The programme con- 
centrated on training, field workshops and research. 
As a result of this activity, awareness of the importance 
of mangroves amongst governments, planners and the 
general pubhc was enhanced and a group of people, 
drawn from all countries of the region, was created 
that could lobby for the proper management of 
mangroves. The first National Mangrove Committees 
were formed by governments in the region and 
consideration on how to manage mangroves properly 
began to permeate the thinking of planners. 

A second programme was supported by UNESCO 
which created a model for evaluating and planning 
the utihsation of a mangrove system. This project 



involved many scientists and students from a wide 
range of countries working together in the field at 
Ranong in Thailand. Later, other mangrove projects 
were launched in Africa, Latin America and the 
Caribbean. 

Following on from the UNDP-UNESCO man- 
grove projects, the International Society for 
Mangrove Ecosystems (ISME) was founded in 1990 
as a non-governmental organisation based in Oki- 
nawa, Japan. The aim of the society is to promote 
research activities and the conservation, rational man- 
agement and sustainable utihsation of mangroves. It 
also acts as an international data bank on mangrove 
ecosystems. ISME has recently adopted a Charter 
for Mangroves to complement the World Charter 
for Nature adopted by the United Nations in 1982. 

In parallel with these developments, the Scientific 
Committee on Oceanic Research (SCOR) in collabo- 
ration with UNESCO's Division of Marine Science 
created a working group on mangrove ecology in 
1979. This group undertook a biosphere inventory of 
mangrove lands and attempted to determine their 
current status. The Commission on Ecology (COE) 
of the World Conservation Union (lUCN) produced 
a report entided Global Status of Mangrove Ecosystems 
(lUCN, 1983), which is widely cited in most reports 
on mangroves. The work of this group was supported 
by the United Nations Environment Programme 
(UNEP) and the World Wide Fund for Nature 
(WWF). lUCN, UNEP and WWF have continued 
their active involvement with mangroves up to the 
present day. 

The Food and Agriculture Organization (FAO) of 
the United Nations has also pursued an interest in 
mangroves, particularly in forest management, and has 
pubhshed reports on mangroves (FAO, 1982 and 
1994). In addition to these activities there has been 
involvement by aid agencies such as the World Bank, 
the Global Environment Fund, US-AID, and the 
European Community. There has also been support 
from many individual countries such as Japan, 
Australia, UK, France and the Scandinavian coun- 
tries. A very recent initiative is a proposal by the 
International Geosphere-Biosphere Programme 
(IGBP) through its Land-Ocean Interactions in the 
Coastal Zone programme to study the economic and 
social impacts of global cUmate change on mangroves. 

The global importance of mangrove ecosystems is 
clearly recognised in Agenda 21 , the most recent and 
widely adopted international environmental resolu- 
tion to date. This is described as a "blueprint for 
action" and, although primarily a voluntary code 
which is not legally binding, many of its principles 
are given legal efiect through the Biodiversity Con- 
vention. Among the major themes running through 
this document is the need for international co- 
operation, integrated management, the preservation 
of vulnerable ecosystems (mangrove ecosystems are 



Introduction 



13 



specifically mentioned), capacity building, and the 
collection and exchange of scientific data usefial for 
management. The document deals specifically with 
the marine and coastal environment and singles out 
the protection of mangrove ecosystems as a priority. 
The most tangible result of all this international 
activity over the past twenty-five years is that the 
ecological and economic importance of mangroves is 
now much better appreciated by all levels of society. 
There is also a well-informed, mutually supportive 
group of people able to argue for better management 
of the mangrove resource. However, there stiU re- 
mains an urgent need to translate this enhanced 
awareness of the importance of mangroves into the 
practice of better management of the mangrove re- 
source. 

A World Mangrove Atlas 

The current work was initiated by the International 
Tropical Timber Organization (ITTO), which is an 
international organisation that aims to promote con- 
servation and sustainable management of tropical 
forest resources, and ISME, with support from the 
World Conservation Monitoring Centre (WCMC), 
Cambridge, UK. ITTO has previously supported 
mangrove projects in Asia, Latin America and Africa 
(see, for example, Clough, 1 993; Diop, 1 993 ; Lacerda, 
1993). 

The compilation of a World Mangrove Atlas is a 
demanding enterprise and this version must be con- 
sidered as a first attempt. We have used the best 
information that we could obtain from a wide range 
of sources, however, we are convinced that using a 
more intensive approach would yield improved data. 
The mapping process is described in more detail in 
the next chapter. The detailed case studies of man- 
groves presented in the regional accounts give a clear 
idea of what can be achieved, in terms of mangrove 
mapping at higher resolutions, given sufficient re- 
sources. These case studies also reveal more of the 
geomorphology, mangrove composition and socio- 
economic condition of the areas under study. 

The area that mangroves occupy is of great interest 
in quantifying their global presence and changing 
status. There are significant difficulties in the calcula- 
tion of such a figure, however, and this matter is 
discussed more fijlly in the next chapter. Problems 
arise in identifying, from satellite photographs, 
whether the vegetation is mangrove or not, in know- 
ing whether the area includes open water surfaces or 
not, and in calculating the area from the GIS maps. 
Although area statistics for the mangrove coverage are 
provided in this work, such figures should be viewed 
with great caution. 

If we are to be able to state whether the area of 
mangrove in the world has increased or diminished 
in twenty years time, due to the activities of people, 
natural disasters or changes in global climate, then we 



must establish a baseline from which to measure the 
change. This atlas is an attempt to summarise the 
available data and to construct such a baseUne. It is far 
from perfect, but it is hoped that it will encourage 
governments and individual scientists to improve the 
data and to provide enough new information to revise 
the World Mangrove Atlas in the future. 

There is no doubt that mangroves are important 
ecosystems biologically, socially and economically. It 
should not be beyond our capability to compile an 
accurate inventory of mangroves around the world 
and to be able to monitor any changes that may take 
place. 

Sources 

clough, B.F. (1993). The Economic and Environmental 

Values of Mangrove Forests and their Present State of 

Conservation in the South-East Asia/Pacific Region. 

Mangrove Ecosystems Technical Report No. 1 . 

International Society for Mangrove Ecosystems, 

Okinawa, Japan. 202 pp. 
Diop, E.S. (1993). Conservation and Sustainable Utilization 

of Mangrove Forests in Latin America and Africa Regions. 

Part II - Africa. Mangrove Ecosystems Technical Report 

No. 3. International Society for Mangrove Ecosystems, 

Okinawa, Japan. 262 pp. 
FAO (1982). Management and Utilisation of Mangroves in 

Asia and the Pacific. FAO, Rome. 160 pp. 
FAO (1994). Mangrove Forest Management Cuidelines. 

FAO, Rome. 319 pp. 
Field, CD. (1995). Journey Amongst Mangroves. 

International Society for Mangrove Ecosystems, 

Okinawa, Japan. 140 pp. 
Field, CD. (Ed.) (1996). Restoration of Mangrove 

Ecosystems. International Society for Mangrove 

Ecosystems, Okinawa, Japan. 250 pp. 
Field, CD. and Darmall, A.J. (Eds) (1987) . Mangrove 

Ecosystems of Asia and the Pacific: Status, Exploitation and 

Management. Australian Institute of Marine Science, 

Townsville. 320 pp. 
Hutchings, P. and Saenger, P. (1987). Ecology of Mangroves. 

University of Queensland Press, Brisbane, Australia. 

388 pp. 
lUCN (1983). Global Status of Mangrove Ecosystems. 

Commission on Ecology Papers No. 3. Saenger, P., 

Hegerl, E.J. and Davie,J.D.S. (Eds). Internadonal 

Union for Conservation of Nature and Natural 

Resources, Gland, Switzerland. 88 pp. 
Lacerda, L.D. (1993). Conservation and Sustainable 

Utilization of Mangrove Forests in Latin America and 

Africa Regions Part I - Latin America. Mangrove 

Ecosystems Technical Report No. 2. International 

Society for Mangrove Ecosystems, Okinawa, Japan. 

272 pp. 
Robertson, A.I. and Alongi, DM. (1992). Tropical 

Mangrove Ecosystems. Coastal and Estuarine Studies. 

American Geophysical Union, Washington, USA. 329 pp. 
RoUet, B. (1981). Bibliography of Mangrove Research 

1600-1975. UNESCO, Rome. 79 pp. 
Torrdinson, P.B. (1986). The Botany of Mangroves. 

Cambridge University Press, Cambridge, UK. 413 pp. 



The Mapping of Mangroves 



Maps came into general use, particularly in Europe, 
in the 15th and 16th centuries. Many of even the very 
earUest of these maps (such as Ptolemy's Cosmographia 
of 1 447) portrayed forests and other vegetation. How- 
ever, the first true vegetation maps, drawn specifically 
to present vegetation, did not appear until the mid- 
nineteenth century. These included the 1858 Flormreiche 
of Brazil, produced by von Martius, which included 
mangroves. 

In addition to their portrayal on terrestrial maps, 
mangroves also appear on many hydrographic charts, 
although here they are frequendy presented as linear 
coastUne features rather than actual areas. It is quite 
hkely that the first regular occurrence of mangroves 
on maps was on hydrographic charts prepared by 
individuals and trading companies, and later by na- 
tional hydrographic oflSces. The Portuguese were 
amongst the first to show mangroves on their charts. 
The first actual use of the term mangrove on a map 
dates back to the early sixteenth century where a 
chart of the coast of Brazil shows mangroves 
('manguez') in the Golfo de los Reyes, just south of 
Rio de Janeiro. During the same period other charts, 
notably of the Moluccas, showed forest areas marked 
as 'alagados' ('inundated'), which were undoubtedly 
mangroves and were of mihtary significance, as they 
were occasionally used by indigenous peoples as a base 
for hiding and attacking the foreign ships (Vannucci, 
1989). 

In recent years the mapping of mangroves has 
become more widespread and they feature not only 
on hydrographic charts, topographic surveys and vege- 
tation maps, but also in natural resource inventories, 
coastal zone management plans, wetland maps and 
coastal sensitivity maps prepared at local, regional and 
national scales. A number of mapping projects have 
also focused entirely on mapping mangroves (see 
Thailand and Tanzania in this work). Data are still 
largely prepared and presented on paper maps, al- 
though they are increasingly being held in digital 
form (as in Belize, Florida, Philippines, Australia, 
Cambodia and Papua New Guinea, in this work). 

Global syntheses on the distribution and status of 
mangrove forests are largely restricted to speciaHsed 
books (Chapman, 1976; lUCN, 1983; Tomlinson, 
1986). These works only contain very coarse scale 
maps and the current work thus represents the first 



attempt to prepare a detailed global synthesis of the 
distribution of mangroves. 

This chapter considers the broader issues of mapping, 
with special reference to mangrove communities. It 
begins with an overview of mapping techniques, and 
some of the problems associated v\ath these, before 
discussing the current mapping project in more detail. 

The importance of maps 

Recent years have witnessed an explosion in the levels 
of information in circulation throughout the globe, 
much of these data having at least some spatial attrib- 
utes. The ability to handle and present data in a 
concise but informative manner is essential, and maps 
are one very powerful tool capable of achieving this. 

Maps also have a strong visual impact and are 
frequently used to promote particular facts or con- 
cepts in a manner far more effective than text or tables. 
They are understood internationally, can show land- 
cover and land-use patterns and can link ofi:en quite 
disparate data, such as infi-astructure, natural vegeta- 
tion patterns or land tenure. Maps can fiirther be used 
in monitoring, calculating changes in area of different 
features, or in modelling and planning processes. For 
these and many other reasons, maps are viddely used 
by land-use planners, pohcy makers, scientists and the 
wider public. 

Maps can convey important information on the 
distribution and status of natural resources, graphi- 
cally illustrating the extent of natural and semi-natural 
vegetation and its spatial relationship with developed 
or agricultural areas. The importance of mangrove 
communities to man for coastal protection, fisheries 
production and supply of natural products, such as 
firewood, timber and charcoal, has been mentioned 
in the introduction. The location of mangroves in the 
coastal zone often places these communities in con- 
flict with other human activities, but inappropriate 
development in the coastal zone can have disastrous 
consequences both for mangrove communities and 
for man. Where conflicts for space do exist, maps are 
an essential tool in providing location information for 
natural resources and in the coastal zone planning 
process. 

The techniques used in the preparation of a map 
depend very much on the uses for which the map is 
required, the scale of the task and the availabUity of 



The Mapping of Mangroves 



15 



resources for the work, such as data, time and funding. 
The global coverage in this atlas is based on the 
compilation of a wide range of existing maps that are 
referenced in each country account. Each of the 
source maps might, itself, have been prepared using 
one or more of the techniques given below. The case 
studies in this adas provide other examples of tech- 
niques for mapping mangroves. 

Ground surveying 

A variety of techniques may be used for ground 
surveying, from the very simple preparation of hand 
sketches and chain surveying to more sophisticated 
techniques of plane table surveying, surveying and 
contouring. It should be noted, however, that many 
of these are very difficult to apply in the complex 
structural environment of a mangrove forest. Theo- 
dolite mapping has been used in most national 
mapping and engineering surveys, but updates to 
these, and new maps, are now frequently based on 
aerial photography and other remote survey methods. 
More complex techniques of ground surveying in- 
clude those developed for geodetic surveying and 
levelling. These allow for the more accurate position- 
ing of the data on the globe, making allowances for 
such factors as the earth's curvature. The mapping of 
vegetation is often a part of the initial surveying 
exercise, and the survey methods used for levelling 
can also be used, for example, in the measurement of 
canopy height. In other cases, vegetation maps are 
often overlaid onto existing topographic maps which 
may have been prepared elsewhere. One of the great 
advantages of the more intensive ground survey meth- 
ods is that they allow for the mapping of species 
distribution, ecological parameters and other features 
not visible from remote platforms. 

Marine charts have often used land-based methods 
for the surveying of accessible coasdines, and they 
now make considerable use of air photos. They have 
also used boat-based surveys, particularly for less 
accessible shores. One problem in boat-based surveys 
has been the fixing of the boat's actual position. For 
this, it is possible to use existing maps and charts, 
astronomical methods and, more recently, it has 
become possible to achieve considerable positional 
accuracy with Global Positioning Systems (GPS). 
Distance to shore and elevation can then be measured 
using techniques similar to those used in land-based 
surveys. Definition of coastline type is largely based on 
visual identification and, because terrestrial features 
beyond the coast are not of major interest and are not 
easily gathered, vegetation, including mangrove forest, 
is rarely presented as an accurately defined area, but 
rather as a length of coast. Other key features of 
hydrographic surveying, such as the collection of 
depth data or the calculation and allowance for tidal 
variation and the estabhshment of a chart datum are 



of httle relevance to this work and not given further 
consideration. 

Remote sensing 

Remote sensing is the term widely applied ro the 
"acquisition of information about the land, sea and 
atmosphere by sensors located at some distance from 
the target of study" (Haines- Young, 1994). Typically, 
this means the gathering and analysis of images ac- 
quired from aircraft, sateUites and even balloons. The 
use of such images was rapidly developed for mihtary 
apphcations particularly during the First and Second 
World Wars. 

In addition to conventional photography, other 
methods of image gathering are now widely used and, 
to better understand all of these, it is useful to consider 
some of the physical processes which lie behind them. 
Different objects show quite different reflectance 
patterns when exposed to electromagnetic radiation. 
This can be seen in the different colours that are 
reflected by different objects in the visible spectrum 
such as green trees and grey buildings, but the same 
phenomenon occurs across the wavelengths of the 
electromagnetic spectrum from x-rays and ultraviolet 
to infrared and microwaves. In addition, certain wave- 
lengths are radiated from objects, particularly in the 
thermal infrared. These different patterns of reflec- 
tance and radiation from different objects are unique 
across a range of wavelengths, and are termed 'spectral 
signatures'. Figure 2.1 shows the reflectance patterns 
of some typical ground features, including water, sand 
and vegetation. Human sight and conventional pho- 
tography are both sensitive to wavelengths in the 
visible spectrum, but it is now possible to build sensors 
that are capable of detecting wavelengths across the 
electromagnetic spectrum. Analysis of these patterns 
may enable the differentiation, for example, of man- 
grove forest from grassland, even from a remote 
location. 

Certain objects may show considerably more 
variation in reflectance over some wavelengths than 
others. For example, vegetation generally shows high- 
est reflectance in the near infrared and reflectance 
patterns vary considerably over relatively small changes 
in vegetation type. It is thus useful to single out these 
wavelengths when studying vegetation patterns with 
remote sensors (see Figure 2.1). Further complexity 
arises when selecting wavelengths for image prepa- 
ration, as the atmosphere 'soaks up' considerable 
amounts of certain energy bands which effectively 
become invisible from a remote platform. 

Any platform capable of picking up these radiating 
wavelengths can be termed a 'passive sensor'. At the 
research level, active sensors are also now frequendy 
used which direct radiation, typically radar wave- 
lengths or laser, towards the earth and then detect the 
reflected waves. 



16 



World Mangrove Atlas 



a 

% 
DC 



100 1 




Band 1 




Band 2 






^ Band 3 






^ 


4 


n 


c h r o 










80 - 








-^ 






.ss^*^ 


60 ■ 










/ 


f 


^ 






^\x 


-^ 


40 - 




X 


/ 


J^ 


^ 


^ 


VEGETATiON 










20 - 


i^t!S^ 


-^ ^ 






u 





__DRYi21i— 






^^: 


=si; 


a= 


,___^ 


/ 




S 1 1' 




n - 


1 1 




' 1- 



0,4 



0,5 



0,6 0,7 

Wavelength (nm) 



0,9 



Figure 2.1 Some typical spectral responses of important ground features (spectral bands refer to SPOT 

1, 2, 3 and the panchromatic channel) 



The development of sensors for uninanned satellites 
necessitated the development of some means of trans- 
ferring data back to earth without physical contact. 
For this purpose electronic scanners were developed. 
These operate with a lens which focuses an image 
onto an array of photoelectric cells which measure 
the amount of radiation being received. The in- 
formation is converted into digital data and then 
transmitted to earth as radio waves. 

Once an image has been obtained, either digitally 
or converted to a map, it must be interpreted. Reflec- 
tance is not the only tool available to the image 
interpreter, other characteristics, such as tone, texture, 
pattern, scale, relationship to other features, and sur- 
face relief may tell a great deal about a ground feature. 
The use of stereo imagery can enhance some of these 
characteristics. It is important to realise that image 
interpretation is a highly skilled process which, if 
undertaken with care and consideration, may improve 
the effective resolution of an image. It is possible, for 
example, that an area of dwarfed mangrove may have 
a very similar spectral signature to another vegetation 
type, but by looking at the patterns of surface drainage 
and relief it may be possible to distinguish one from 
the other. Such interpretation requires at least some 
knowledge of the distribution and ecology of man- 
groves. 

Preparing maps from images 

Remotely sensed images can be used to annotate or 
update existing maps or create entirely new maps. 
Traditional photographic images can be utilised di- 
rectly, using analogue photogrammetric techniques 



that have been developed and widely used since the 
1940s. Alternatively there are a number of methods 
of transferring the data to Geographical Information 
Systems (GIS) or other software systems where they 
can be manipulated with relative ease to correct 
geometric distortion and to undertake subsequent 
data analysis. 

The simple visual interpretation of a sateUite image 
can yield considerable information from a thematic 
viewpoint, however the conversion of such an image 
to a specified map projection usually requires geo- 
metric corrections, which are only possible with 
image processing software or, at least, a GIS. Digital 
image processing typically involves the enhancement 
of the contrasts between features, facilitating their 
interpretation. Although sateUites already have their 
sensors tuned to specific wavelengths, further work 
can be undertaken to drop out or enhance particular 
wavebands in order to maximise differentiation of 
particular features. Known features on the ground can 
have their spectral signature analysed and software 
packages can be programmed to find all other areas 
with similar reflectance characteristics, producing a 
'classified image'. This method is known as a super- 
vised classification. Alternatively algorithms can be 
written to identify areas of similar reflectance auto- 
matically (unsupervised), and these can then be iden- 
tified on the ground. 

The development of GIS has closely paralleled that 
of image processing systems, and there is now a 
considerable overlap between the capabilities of the 
two. The former specialise in handling related, spa- 
tially referenced data, typically combining mapped 



The Mapping of Mangroves 



17 



information with a database and analytical tools. The 
notable advantages conferred by GIS include the 
abdity to update information rapidly, to undertake 
comparative analytical work, to combine data from 
multiple sources, which may also be of differing age 
and scales and to link further data to maps in a variety 
of different ways. These and other mapping software 
tools are increasingly used by cartographers around 
the world. 

Ground-truthing 

With all remote sensing techniques it is necessary to 
undertake 'ground-truthing' in order to mterpret and 
validate with certainty the features identified in im- 
ages. Such work involves visiting a number of test 
sites, usually with a copy of the remote image in its 
raw form or partially processed. Detailed descriptions 
can then be gathered of the features of interest to the 
observer, together with other features which may 
interfere with these due to strong or conflicting 
spectral signatures. It may, for example, be necessary 
to note the features of soil or drainage as well as 
vegetation in order to produce a useful spectral 
classification for subsequent image analysis. Equally 
important is to ensure that data gathered in the field 
have accurate geographic locations. This is commonly 
done using Global Positioning Systems (GPS), but can 
be achieved equally well by linking to features on the 
ground which are clearly visible in the remote image. 
Also iinportant is to take a large enough number of 
samples, and to ensure that individual samples are 
sufficiendy large. Sample size will vary depending on 
the resolution or pixel size of the original image. 
Some surveys use ground-based remote sensing, 
employing cameras and radioineters, to get more 
accurate information relating to the spectral signa- 
tures of different ground features. 

Scale and resolution 

The scale of a map is a measure of the reduction of 
the size of features on that map. Resolution is a related 
term. It is a more direct measure of the detail shown 
on a map and refers to the minimum size of an object 
visible on a map or the minimum distance by which 
two objects must be apart for them to appear separate. 
The characteristics portrayed in the spatial repre- 
sentation of any natural system are strongly related to 
scale and resolution, and these need to be seriously 
considered by those responsible for the preparation 
of maps and by the users. A number of problems can 
arise, especially in the generation of statistics and the 
comparison of maps drawn at different scales. 

This is illustrated by attempts to measure coasthne 
length: the complexity, and hence the length, of any 
coastline shown on a map is a fianction of map 
resolution. In the Caribbean, for example, maps of 
individual islands frequently show great detail, includ- 
ing tiny offshore rocks and islets. Regional maps, by 



contrast, may summarise complex coasdines into a 
few simple lines, while world maps often leave out 
many Caribbean islands altogether. Measuring the 
length of coasthne of any island from each of these 
maps would yield three very different results. 

With traditional photography, the resolution or 
level of detail can be altered by varying the lens and 
photographic material, or by altering the height from 
which nnages are taken, although a balance must be 
struck between the area covered by the image and the 
detail or resolution to be found in the resulting image. 
Optical scanners gather light from a continuous grid 
of defined blocks, known as pixels. The sensor records, 
for each pixel, the reflectance levels of those wave- 
lengths to which it is tuned. The resolution is largely 
a function of pixel size, which is dependent on the 
optics of the sensor and the height at which the 
images are taken. These parameters cannot easily be 
varied for satellites. A suminary of the sensors in the 
most coirmionly used satellites is provided in Table 2.1. 
Data from all of these satellites have been used in the 
preparation of the source maps for this atlas. 

The problems posed by scale are not simply those 
of statistics. Entire natural phenomena will be hidden 
or exposed depending on the scales of study. This is 
of particular relevance in the coastal zone where 
many narrow hnear features are likely to be com- 
pletely lost at low resolutions. 

This atlas provides examples of some problems of 
scale. None of the 25 regional maps has a base scale 
much greater than 1 :5 miUion. At this scale 1 centi- 
metre on the map represents 50 kilometres on the 
ground, and it is very difficult to see features with a 
diameter of less than 2 kilometres. Extensive areas of 
the world's coasts have sparse mangrove communities, 
groups of just a few trees or fringe communities only 
a few metres wide. These communities m.ay be im- 
portant in terms of the geographical distribution of 
mangroves. They may also have local significance in 
providing propagules for the colonisation of man- 
grove areas, habitat for fauna and stabilisation of 
embankments. Few of these communities are clearly 
shown on the regional maps in this document. In 
contrast, some of the case studies in this adas have 
been prepared at very high resolutions where it is 
possible to distinguish features measured in metres 
rather than kilometres and to differentiate areas within 
a mangrove community showing, for example, differ- 
ent species composition, or canopy height. 

Comparison of methods 

Traditional survey methods provide for extremely 
high-resolution mapping and can further allow for 
identification of many features invisible from remote 
locations, including species, and certain physico- 
chemical parameters of the environment. They are, 
however, usually time-consuming, costly and not well 
adapted to mapping large areas. 



18 



World Mangrove Atlas 



Table 2.1 A summary of the main satellites used for vegetation mapping, together with their sensor 

specifications. Abbreviations used are defined below the table 



Satellites and 


Band number and 


Spatial resolution 


Repetition rate 


Altitude 


Suitable 


sensors 


spectral coverage 


(pixel size) 


and size of image 




mapping scale 


NOAA-AVHRR 


1 0.58-0.68 urn 


HRPT, LAC 1 km 


Daily 


1,4.50 km 


Global and regional 


(since 1978) 


2 0.725-1.1 lam 


GAC 4 km 






from 1:1,000,000 




3 3.55-3.95 ^m 


GVl 15 km 


2,700 X 2,700 km 




to 1:10,000,000 




4 10..5-11.3nm 












5 11.5-12.5 urn 










Landsat MSS 


4 0.45-0.6 nm 


79 X 79 m 


1 6 days 


915 km 


National 


(since 1972) 


5 0.56-0.7 Jim 






and 


from 1:200,000 




6 0.67-0.8 nm 




180 X 180 km 


705 km 


to 1:1,000,000 




7 0.78-1.1 urn 










Landsat TM 


1 0.45-0.52 urn 


30 X 30 m 


1 6 days 


705 km 


Local 


(since 1982) 


2 0.53-0.61 urn 


or 






from 1:50,000 




3 0.62-0.69 urn 


120 X 120 m 


180 X 180 km 




to 1 :200,000 




4 0.78-0.91 urn 


(Band 7) 










5 1.57-1.78 urn 












7 2.10-2.35 nm 












(6 10.4-12.6 urn) 










SPOT HRV 


1 0.50-0.59 urn 


20 X 20 m 


26 days 


833 km 


Local 


(since 1986) 


2 0.615-0.68 i^m 


(10 X 10 m) 






from 1 :50,000 




3 0.79-0.89 |jm 




60x60 km 




to 1:200,000 




(Panchromatic 












0.51-0.73 uni) 










ERS-1 and 2 


SAR 5.3 GHz 


30 X 30 m 


Almost daily 


785 km 


Local 


(since 1991) 


Band C 5-7 cm 




100 km 




from 1:50,000 
to 1:100,000 



NOAA-AVHRR Advanced Very High-Resolution Radiometer HRPT 

Landsat MSS Landsat Multi-Spectral Scanner LAC 

Landsat TM Landsat Thematic Mapper GAC 

SPOT HRV SPOT High-Resolution Visible GVI 

ERS-1 and 2 European Radar Satellite 



High-Resolution Picture Transmission 
Local Area Coverage 
Global Area Coverage 
Global Vegetation Index 



Aerial photography also allows for comparatively 
high-resolution mapping (scales of up to 1:2,000, 
enabling ineasurement of objects even just a metre or 
so across). It has a longer historical record than satellite 
imagery in many countries, allowing for the use of 
comparative data from as early as the 1940s. Photo- 
graphs are also well adapted to stereo image prepara- 
tion, although these are now also obtainable from 
SPOT images, and they can be relatively cheap to 
analyse, especially if only a small area is under survey. 
Aerial surveys can be tailored to the particular needs 
of specific users. The high-resolution and use of 
particular film have enabled the study of tree disease 
and pollution damage. The use of Side Looking 
Airborne Radar (SLAR) has a number of advantages, 
most notable is its ability to penetrate cloud or to survey 
at night. It generally produces images of slightly 
lower resolution than conventional aerial photogra- 
phy. SLAR images have been used for vegetation 
mapping, especially in areas prone to considerable 
cloud cover, and they can be used to difierentiate 



mangrove communities. Radar images are now avail- 
able from sateUites (ERS-1, ERS-2, J.ERS). As with 
airborne radar, they are of considerable interest in 
enabling cloud penetration, but their use in inangrove 
inapping is still only at the research level. 

Satellite imagery has been available since the launch 
of the first Landsat platform in 1972. Although reso- 
lution is improving it is still hmited, at best, to pixels 
of side 10 or 20 m. The advantages, however, are 
numerous. Very large areas can be covered relatively 
cheaply, a wide variety of spectral bands can be 
covered, and data can be collected fi-equendy and 
regularly. The data are available in digital format, 
which is usefijl for processing and incorporating into 
a GIS. In general, for vegetation mapping the higher 
resolution 'earth resources satellites' (e.g. Landsat and 
SPOT) are more usefial than the 'environmental 
satellite systems' (e.g. NOAA-AVHRR), whose data 
are primarily used in meteorology. Although satellite 
data are regularly collected, the satellites have a fixed 
path and cannot be directed: it is thus not possible to 



The Mapping of Mangroves 



19 



get data from different times of day with the sun-syn- 
chronous satellites (Landsat and SPOT), nor is it 
possible to guarantee data from cloud-free days. Even 
after 20 years of Landsat imagery there are still some 
areas that have not been viewed under cloud-free 
conditions. 

Further comparisons of remote sensmg methods 
are provided in the case studies included in this atlas, 
and mention of this is made later in this chapter. 

The portrayal of mangroves 

Man-made or man-modified features such as roads, 
buildings and fields are relatively easy to portray on a 
map, as they can usually be clearly defined with sharp 
lines. Natural features are generally far less easily 
delimited and, even with strict definitions, are some- 
what subjectively defined by systems that require 
points, hnes and polygons to set liinits on features that 
may, more realistically, be gradients and patchworks 
and, in turn, may be transitional or seasonal. In most 
cases the process of transferring information to maps 
requires a considerable ainount of data aggregation 
for the sake of clarity and integrity. Even the coastline 
proves a feature of some difliculty to cartographers 
due to problems of tidal fluctuations. There has tradi- 
tionally been very Utde overlap between the charts 
for marine navigation and maps for terrestrial features. 
The former often measure depths below sea level 
from a different point (datum) in the tidal cycle than 
the latter measure heights above sea level. 

The term 'mangrove' has been used variously to 
define a constituent group of plants and the commu- 
nities in which these occur. Other terms for these 
communities include coastal woodland, intertidal for- 
est, tidal forest, mangrove forest, mangrove swamp and 
mangal. To define the mangrove community it is 
necessary firsdy to define the constituent mangrove 
plants: these are shrubs or trees (and including ferns 
and palms) which inhabit the intertidal zone. They 
are a polyphyletic group from a wide range of famiUes, 
which makes the development of a strict definition 
difficult. The total number of mangrove species varies 
from author to author, although most would agree on 
a minimum hst which would include the dominant 
species in most simations. The definition of a mangrove 
community would be that of a habitat dominated by 
one or more of these species. The text and tables in 
this work use a list of some 70 mangrove species, 
adapted from Duke (1992). It should be noted, how- 
ever, that the maps themselves are drawn from sources 
which rarely define the mangrove communities that 
they map. The only case where this is likely to cause 
concern is with Nypa dominated forests. Nypa, which 
is related to the palms, is probably oinitted from the 
mangrove areas on some maps. This is unlikely to be 
noted, even in map keys, and is thus difficult or 
impossible to correct. 



Further difficulties arise in the preparation of maps 
from defining areas which could be seen as integral 
to the mangrove ecosystem, such as salt pans (tannes 
or blanks), creeks, mudflats, or areas with dwarfed or 
sparsely distributed trees. Some workers may include 
these areas as part of the ecosystem, others will not. 
Their approach is likely to be further influenced by 
the problems of scale noted above. The landward 
inargin of a mangrove forest may be delimited by any 
one of a number of different systems, but where the 
forest grades into another forest system, such as swamp 
forest or lowland rainforest the change may be gradual 
and virtually imperceptible, presenting yet fijrther 
problems for the cartographer. 

Despite these apparent differences of definition it is 
relatively easy in most areas to describe and map 
mangrove communities. The commonest mangrove 
species are agreed upon by most authors (with the 
possible exception of Nypa), and where these form 
dense communities they can usually be defined clearly. 
Frequently they can be seen from the air or surveyed 
from the land or sea and have clear boundaries where 
the trees stop. 

Existing mangrove mapping 

Mangroves make up a significant part of many tropical 
and near-tropical coasts, lagoons, estuaries and deltas. 
As such they are portrayed on a wide range of maps. 
Many countries mark mangroves on general topo- 
graphic surveys, and they are often marked, at least as 
linear features, on marine charts to aid navigation. In 
both of these cases mangroves are rarely defined. In 
the latter case they are rarely shown as polygons and 
may not be shown if they are in lagoons and so not 
visible from the sea. Typically, national topographic 
maps have developed over many years and the source 
material is a complex patchwork of different surveys 
made from the ground, the air and space. The most 
reliable maps are vegetation maps, which are increas- 
ingly available at both national and regional levels. In 
all of these cases, the maps may have been prepared 
from one or more of the survey methods described. 
Despite all of these comments it remains relatively 
unusual to find a recent map showing mangroves at 
a usefiil scale. Revision of national topographic map 
surveys is currendy at about 1% per year, and this 
figure is much lower for regions in Africa and South 
America (Howard, 1991). 

The present approach to global mangrove 
mapping 

This work represents the first attempt at the prepara- 
tion of a global map of mangrove forests. Gathering 
global mapped data has been undertaken by the 
World Conservation Monitoring Centre (WCMC) 
in the past for a number of other publications. Of 
greatest relevance for the current work has been the 
preparation of The Conservation Atlas of Tropical Forests, 



20 



World Mangrove Atlas 



a three-volume series (Collins et a/. , 1 99 1 ; Sayer et al. , 
1992; Harcourt and Sayer, 1996). This very large 
undertaking led to the development of forest maps, 
including mangroves, for all of the major wet-tropical 
forest countries. For Tlu Conservation Atlas of Tropical 
Forests, original data were gathered by a major search 
process which involved correspondence and discus- 
sion with mapping agencies, government authorities, 
non-government organisations interested in conser- 
vation, international agencies and scientists. Data 
requests led to the gathering of data in numerous 
forms, ranging from detailed digital data sets to sketch 
maps. These data were incorporated into the GIS 
system at WCMC where they were harmonised and 
prepared for publication. Using the same GIS it has 
been possible to extract the mangrove coverage from 
these maps to act as a starting point for the current adas. 

The primary aim of the current work has been to 
build on the existing data set for mangrove forests by 
identifying gaps, which include the coasts of dry 
countries and small island nations, updating obsolete 
data, improving low resolution data and seeking 
new data sets. Data gathering was undertaken along 
similar lines to those used for the production of The 
Conservation Atlas of Tropical Forests, through corre- 
spondence and discussion with mapping agencies, 
governinent authorities, non-governmental organisa- 
tions, international agencies and individual scientists. 
In particular, the search effort has been more focused 
on mangrove experts in many countries. Help and 
advice was sought from members of the International 
Society for Mangrove Ecosystems (ISME), the staff of 
the Laboratoire d'Ecologie Terrestre,Toulouse,France 
and many other centres of mangrove expertise. As 
well, extensive searches of the literature were carried 
out. 

Much new data were obtained, including detailed 
digital data sets for a number of countries, printouts 
from other GIS systems, unpublished reports and 
published maps. In some cases confirmation was given 
that the data already held at WCMC were sufficiently 
accurate. Elsewhere, WCMC provided base maps to 
country experts for annotation which were then 
returned for digitising. 

The twenty-five regional maps in this atlas repre- 
sent the first map summary of the distribution of 
mangroves at the global level. Mangroves are thought 
to occur in some 112 countries and territories (in- 
cluding many small island nations where the total 
mangrove area is very small) . Between them, the maps 
show the distribution of mangroves in one hundred 
countries and thus provide a detailed picture of overall 
distribution patterns at the global and regional level. 
The remaining countries, for which data were not 
found, are all known to have only a small area of 
mangroves, unlikely to influence the general appear- 
ance of the regional distribution maps. 



The information presented may not always be the 
best available, and it is not necessarily strictly compa- 
rable across country boundaries. This will depend on 
the source data, and the age of the data. With more 
time and a larger budget, it would have been possible 
to develop a more consistent approach, yielding more 
recent and accurate data for many countries. 

Case studies 

The regional mangrove maps in this atlas have been 
supplemented by a number of case studies. These have 
examined a few selected mangrove areas in much 
greater detail. There are very few published papers spe- 
cifically relating to mangrove studies using remotely 
sensed data, despite the relatively large number of 
studies deahng with other tropical forest systems. 
Remote sensing is a tool which cannot be used alone 
in the mangrove environment. It must be used vidth 
appropriate 'ground-truthing',and the importance of 
this is shown in the various case studies provided. As 
a general rule, the data extracted from satellite sensors 
are directly related to the density of the ecosystem, its 
main floristic components, its phenological stage or 
physiological status. It is not yet possible to use 
satellite imagery to derive accurate and reliable data 
on canopy height, forest stratification, species identi- 
fication, timber volume or standing biomass. However, 
it IS possible to discriminate mangroves from neigh- 
bouring ecosystems, to delineate mangrove areas, to 
provide information on their density and degradation, 
and to monitor changes due to natural and man-in- 
duced hazards, such as cyclones, surges and floods. 
Such information may be achieved using high- 
resolution data such as Landsat TM, SPOT HRV, 
combined, or not, with ERS data. Some of the most 
recent satellite image interpretation has looked at 
photosynthetic activity and primary productivity of 
forests, but, so far, mangrove areas have not been 
studied. It should further be noted that in some cases 
mangrove inventories require higher accuracy than is 
currently achievable from satellite imagery and in 
these cases (1:20,000-1:50,000) aerial photography 
remains a more powerfiil tool. 

The case studies presented in this atlas have been 
selected to illustrate at least a part of the range of 
mangrove ecosysteins, based on: 

• biogeography 

• coastal environment 
(bioclimate, geomorphology) 

• structural properties 

(size and density of the trees) 

• human usage and exploitation 

In addition to this, the data presented have used 
information from all of the most commonly used 
satellites such as NOAA-AVHRR, Landsat, SPOT 
and ERS-1. In these terms, a summary of what the 
different case studies show is outlined overleaf. 



The Mapping of Mangroves 



21 



Bay of Bengal, India and Bangladesh 

The two studies provide a composite of the foil range 
of scales from low resolution data (NOAA-AVHRR), 
to high (SPOT and aerial photography): 

• Ganges-Brahmaputra - a huge area of deltaic 
mangroves, including both natural systems and 
plantations, showing cyclone damage and con- 
version to agriculture. 

• Cauvery Delta (Pichavaram) - a small area of 
coastal lagoon mangroves on a dry coast, showing 
forest clearance. 

Ranong, Thailand 

High-resolution Landsat TM imagery is shown. The 
site consists of estuarine mangroves in a relatively 
natural system. 

Balochistan, Pakistan 

High-resolution imagery showing the mangroves of 
Sonmiani Bay is provided. The coastal region is highly 
arid and sahne. The mangroves are sparse with stunted 
tree growth. 

French Guiana 

This shows the use of radar data from ERS-1 com- 
bined with SPOT. The country has both estuarine 
and coastal mangroves, showing zonation and natural 
degradation. 

Sine-Saloum, Senegal 

Two types of high-resolution satellite imagery, Land- 
sat MSS and SPOT, are shown. These are sahelian 
mangroves, arid and degraded. 

Gabon 

This study illustrates the use of aerial photography. 
The sites shown are relatively natural estuarine sys- 
tems, with dwarfed trees away from the river banks. 

Gambia 

High-resolution SPOT imagery has been used. 
Riverine mangroves are shown. The trees are well 
developed with a high density and a high canopy. 

Spatial accuracy 

Some mention has already been made of the problems 
of scale. Data prepared at high-resolution will show even 
very small areas of mangrove, while at low resolutions 
such areas may be omitted, or their size may be exag- 
gerated. Exaggeration of size at low resolutions may 
occur when, for example, a number of smaller areas are 
coalesced into a single polygon which actually includes 
areas of non-mangrove, or when areas of bays or rivers 
are simply infilled with mangrove. Low resolution 
sateUite imagery may exaggerate or reduce an actual 
mangrove area, depending on the techniques that are 
appUed and the spatial distribution of a given mangrove 
area. To be detected within a one square kilometre pixel, 
mangroves must occur over an area large enough to 



produce a sufficient reflectance for detection. Small 
patches are likely to be omitted, as are larger areas if 
these are Linear and quite narrow. In some circum- 
stances, however, the actual area may be exaggerated 
by the same imagery. It is possible for individual pixels 
to be recorded as inangrove even when the total area 
of mangrove is much less than one square kilometre, 
depending on such factors as the reflectance of sur- 
rounding features and the wave-bands being used in 
the analysis. 

Areal estimates 

Knowledge of the mangrove area in any country or 
region is important for pohcy-making, planning and 
resource management. With the increasing concern 
over the loss of mangrove areas in many countries 
there is also an urgent need to assess the scale and rate 
of this loss. To undertake such work, accurate calcu- 
lations of areas are necessary, and these must be 
repeatable over time. 

In this atlas, the total area of mangrove, as shown in 
the regional maps, is provided in the country tables 
and was generated fi-om the GIS. There is reason to 
treat some of these figures with caution. In part, this 
is because of the issues of scale and spatial accuracy 
but problems of definition and interpretation also 
affect the calculation. A one square kilometre pixel 
resolution, especially in a small country, will be of little 
or no value in the calculation of the total mangrove 
area for that country. For larger countries the same 
errors arise, although the percentage error is likely to 
be less. 

It is rare for map sources to provide a detailed 
definition of what they have called 'mangrove' so it 
is possible that, for some maps, 'mangrove' may 
include areas of swamp forest, saltmarsh or mudflat; 
or may exclude areas of Nypa. In some areas there 
iTiay be further problems of misidentification. Thus, 
for example, in Venezuela it has been suggested that 
estimates of inangrove area may have been consistently 
overestimated by over 100% as they have included the 
non-mangrove species Symphonia globulifera which is 
a swamp-forest species, difficult to distinguish from 
mangroves in remote images. If this is indeed the case, 
it may have forther ramifications for a number of 
other countries in the region as S. globulifera is a 
relatively widespread species. It is difficult to estimate 
the magnitude of these problems but, in the opinion 
of the editors, they are probably not widespread. 

The uncertainty in areal calculation has resulted in 
the provision of a second figure for mangrove area in 
the country tables, described as the 'alternative 
estimate of mangrove area'. This figure is taken from 
a recent, rehable source (referenced). In many cases 
this figure may be more accurate than the figure 
generated from the maps. Where either figure is 
considered to be very unreliable it is placed in paren- 
theses. When citing areas, it is also important to 



22 



World Mangrove Atlas 



include the date of the source information as man- 
grove areas in some countries may have changed 
considerably smce the data were origmally prepared. 
Readers are strongly encouraged to refer to the source 
material which is referenced for each country. It is 
possible, using this information, to assess the age, 
quaUty and scale of each country coverage and to use 
the data accordingly. Of the two areal figures provided 
that which is considered to be the most reliable, in 
the opinion of the editors, is marked with a '#'. These 
figures have been used in the generation of regional 
and global statistics in the next chapter. 

Despite these problems, the area estimates presented 
here, derived from the maps or alternative sources, 
represent a summary of the best available areal esti- 
mates for most countries in the world. Furthermore, 
the maps themselves provide an important record of 
the spatial distribution of mangroves around the world. 
This has never been available until now, and the maps 
and related data thus represent a unique and valuable 
baseline on which future work can build. 



Kuchler, A.W and Zonneveld, I.S. {\9SS). Vegetation 

Mapping. Handbook of Vegetation Science 10. Kluwer 

Academic Publishers, Dordrecht, The Netherlands. 

635 pp. 
Miller, R.I. (1994). Mapping the Diversity of Nature. 

Chapman and Hall, London, UK. 218 pp. 
Sayer,J.A., Harcourt, C.S. and Collins, N.M. (1992). The 

Conservation Atlas of Tropical Forests: Africa. Macirullan 

Press Ltd, London, UK. 256 pp. 
Toirdinson, P.B. (1986). Tlie Botany of Mangroves. 

Cambridge University Press, Cambridge, UK. 413 pp. 
Vannucci, M. (1989). Tlw Mangroves and Us. Indian 

Association for the Advancement of Science, New 

Delhi, India. 203 pp. 



Sources 

Budd,J.T.C. (1991). Remote sensing techniques for 

monitoring land-cover. In: Monitoring for Conservation 

and Ecology. Goldsinith, F.B. (Ed.). Conservation 

Biology Series. Chapman and Hall, London, UK. 

pp. 15-59. 
Chapman, VJ. (1976). Mangrove Vegetation. Cramer, Lehre, 

Vaduz, Liechtenstein. 425 pp. 
Clayton, K. (1995). The land from space. In: 

Environmental Science for Environmental Management. 

O'Riordan, T (Ed.). Longman Scientific and Technical, 

Harlow, UK. pp. 198-222. 
Collins, N.M, Sayer,J.A. and Whitmore, TC. (1991). 

The Conservation Atlas of Tropical Forests: Asia and the 

Pacific. MacmiHan Press Ltd, London, UK. 256 pp. 
Duke, N.C. (1992). Mangrove floristics and 

biogeography. In: Tropical Mangrove Ecosystems. 

Robertson, A.I. and Alongi, DM. (Eds). Coastal and 

Estuarine Series 41. American Geophysical Union, 

Washington DC. pp. 63-100. 
Haines- Young, R. (1994). Remote sensing of 

environmental change. In: The Changing Global 

Environment. Roberts, N. (Ed.). Blackwell Publishers, 

Oxford, UK. pp. 22-43. 
Harcourt, C.S. and Sayer.J.A. (1996). Tlie Conservation 

Atlas of Tropical Forests: the Americas. Simon and 

Schuster, New York, USA. 335 pp. 
Howard.J.A. (1991). Remote sensing of forest resources: 

theory and application. In: Remote Sensing Applications. 

Chapman and Hall, London, UK. 420 pp. 
lUCN (1983). Global Status of Mangrove Ecosystems. 

Commission on Ecology Papers No. 3. Saenger, P., 

Hegerl, E.J. and Davie, J.D.S. (Eds). International 

Union for Conservation of Nature and Natural 

Resources, Gland, Switzerland. 88 pp. 



3 



The Global Distribution of A4angroves 



Mangroves are largely confined to the regions be- 
tween 30° north and south of the equator, with 
notable extensions beyond this to the north in Ber- 
muda (32°20'N) and Japan (3r22'N), and to the 
south in Austraha {38°45'S), New Zealand (38°03'S) 
and the east coast of South Africa (32°59'S). Within 
these confines they are widely distributed, although 
their latitudinal development is restricted along the 
western coasts of the Americas and Africa, as com- 
pared to the equivalent eastern coasts. In the Pacific 
Ocean natural mangrove communities are limited to 
western areas, and they are absent from many Pacific 
islands. 

Figure 3.1 shows the global distribution of man- 
grove communities. This represents a global synthesis 
of the data gathered for, and presented in, this atlas. To 
enhance the visibihty of the smallest sites, which 
wfould otherwise not show at this scale, the bounda- 
ries of all sites have been enlarged and thus should not 
be regarded as indicative of actual inangrove area at 
any one site. 

There are two main centres of diversity for man- 
grove communities which have been termed the 
western and eastern groups (Tomlinson, 1986). The 
eastern group broadly corresponds with the Indo- 
Pacific and is bound to the east by the limits to natural 
mangrove occurrence in the west and central Pacific, 
and to the west by the southern tip of Africa. The 
western group fringes the Afi-ican and American 
coasts of the Atlantic Ocean, the Caribbean Sea and 
the Gulf of Mexico, and also includes the western 
(Pacific) coast of the Americas. These two regions 
have quite different floristic inventories, and the east- 
ern region has approximately five times the number 
of species that are found in the western region. 

The distribution patterns of mangroves are the 
result of a wide range of historical and contemporary 
factors. Perhaps the most obvious distribution pat- 
terns, the latitudinal limits, are largely set by low 
temperatures, both sea surface temperatures and air 
temperatures, and particularly by extremes of tem- 
perature. Rainfall also has a strong influence over 
mangrove distribution, largely through the reduction 
of salinity in an otherwise highly saline environment. 
Although mangroves are adapted to saline or brackish 
environments the high sahnity of seawater, and the 
sometimes higher sahnities associated wdth intertidal 



areas, particularly in arid countries, frequently restrict 
growth. In areas with low, irregular or limited seasonal 
rainfall the number of mangrove species which can 
survive is limited. This is clearly one of the major 
factors leading to sparse mangrove development over 
wide areas of coast, such as around the Arabian 
Peninsula. Historical and tectonic factors are probably 
responsible for the easterly limit to mangrove devel- 
opment in the Pacific, although exact mechanisms for 
these hinits are unclear. It may be that mangroves were 
once more widely distributed in this ocean and have 
undergone range constrictions, alternatively the cur- 
rent distributions could represent the eastern hmits 
to dispersal firom a western centre of origin. At the 
national and local level, many other factors influence 
the distribution of mangroves, including soils, tides, 
geomorphology, mineral availability, soil aeration, 
winds, currents and wave action. The influence of 
man is now considerable and is affecting mangrove 
distribution patterns at all scales. 

The total global area of mangroves 

Mention has been made previously of the difficulties 
of calculating the area of mangroves for different 
countries. This atlas includes a comprehensive assess- 
ment of the total mangrove area statistics for every 
country in the world. In most cases, two estimates are 
presented, one calculated from the map, the other an 
alternative best estimate from a given source. In order 
to derive summary statistics the editors have, as ob- 
jectively as possible, selected firom these two figures 
that which, in their opinion, is likely to be the more 
accurate. These figures (marked with a '#') have been 
used in the calculation of the regional statistics pre- 
sented below. 

According to these data (Table 3.1), the total area of 
mangroves in the world is some 181,000 square kilo- 
metres (sq km). This figure, and the regional totals, 
compare favourably with estimates prepared by Fisher 
and Spalding (1993), but considerably less well with 
the figures provided in lUCN (1983). The latter 
document is older and does not cover all countries, 
notably in the Red Sea and Arabian Gulf areas and parts 
of the Americas: Florida, Bahamas and Lesser Antilles. 
The overlap in the material used in each of these 
references is minimal, so the figures can be taken as 
being effectively independent. Approximately haff of 



24 



World Mangrove Atlas 



Table 3.1 Estimates of mangrove areas, together with percentage figures of global totals 



Region 



Mangrove Area (sq km) 
(this atlas) 



Mangrove Area (sq km) 
lUCN (1983) 



Mangrove Area (sq km) 
Fisher and Spalding (1993) 



South and Southeast Asia 

Australasia 

The Americas 

West Africa 

East Africa and the Middle East 



75,173 (41.5%) 
18,789 (10.4%) 
49,096 (27.1%) 
27,995 (15.5%) 
10,024 (5.5%) 



51,766(30.7%) 
16,980 (10.0%) 
67,446 (40.0%) 
27,110(16.0%) 
5,508 (3.3%) 



76,226 (38.3%) 
15,145(7.6%) 
51,286(25.8%) 
49,500 (24.9%) 
6,661 (3.4%) 



Total Area 



181,077 



168,810 



198,818 



the figures used for the current assessment have been 
calculated from the mapped data, while most of the 
remainder are from very recent references. 

Changes in mangrove area 

The areal statistics in Table 3.1 give a reasonable 
assessment of the total area of mangroves in the world 
but there are likely to be considerable margins of 
error. These can be related to the problems of areal 
calculation described in the previous chapter. Due to 
differences in definition, age, scale and accuracy of 
different national sources, the use of global composite 
statistics as a baseline for monitoring changes in global 
mangrove area should be employed with extreme 
caution. Any future composite figures derived in a 
similar way will probably be subject to similar errors. 
There is an urgent need in most places for more 
accurate mapping of mangrove areas at much higher 
levels of resolution. A compilation of data from more 
accurate maps would lead to a more reliable baseline 
for measuring change. The case studies included in 
this atlas give an indication of what can be achieved 
but such information is, unfortunately, all too rare at 
the present tune. 

An effort was made by the editors to present, within 
the text, figures showing mangrove loss in those 
countries where these exist (see regional accounts). 
Such figures are not available for most countries, but 
where these do exist there is an indication that 
significant decreases in the global mangrove area have 
already occurred. In Southeast Asia, for example, the 
loss figures for four countries are: Malaysia - 1 2% from 
1 980 to 1 990; the Philippines - 4,000 sq km originally 
to 1 ,600 sq bn, today; Thailand - 5,500 sq km in 1961 
to 2,470 sq km in 1986; and Vietnam - 4,000 sq km 
originally to 2,525 sq km, today. These figures suggest 
a total of some 7,445 sq km of mangrove loss, repre- 
senting over 4% of the current global total. The four 
countries concerned have suffered significant man- 
grove loss but they are not alone. Ong (1995) 
considers that the 1% loss of mangrove area per year 
in Malaysia is a conservative estimate of destruction 
of mangroves in the Asia-Pacific region. Indeed, there 
are very few national accounts in this atlas which do 



not list considerable threats to the mangrove environ- 
ments. 

In counter to this, the increasing area of mangrove 
plantations in some areas is worthy of note. Plantations 
in Bangladesh, Vietnam and Pakistan now cover over 
1 ,700 sq km, while Cuba is reported to have planted 
some 257 sq km of mangroves. A companion volume 
to this atlas. Restoration of Mangrove Ecosystems (Field, 
1996), considen in detail the planting of new mangrove 
areas. 

One further comment concerns the dominance of 
the areal statistics by a few countries. Notable among 
these are Indonesia (42,550 sq km) , Australia (11,500 
sq km), Brazil (13,400 sq km) and Nigeria (10,515 sq 
km). In total, these countries have some 43% of the 
world's mangroves and each has between 25% and 
50%i of the mangroves in their respective regions. 
Indonesia alone has 23%i of the world's mangroves. 
Aside from the general geographical interest of this 
situation, it is clear that these four countries have a 
considerable heritage. Political and management 
decisions relating to mangroves in each of these 
countries will have a significant effect on the global 
status of mangrove ecosystems into the future. 

Protected areas 

One of the most widely used tools in mangrove 
conservation is that of legal protection through the 
designation of protected areas (national parks, nature 
reserves and other categories). Figure 3.2 shows the 
global distribution of protected areas with mangrove 
habitat. There are some 685 protected areas contain- 
ing mangroves globally, distributed between some 73 
countries and territories. Statistics are rarely available 
which show the area of mangrove habitat within these 
sites, and such figures cannot be calculated from the 
total areas of these sites. It is possible, however, to get 
a very general picture of the distribution of mangrove 
protection at the global level, and more particularly 
to draw attention to the obvious holes in the pro- 
tected area network. Most of the countries with very 
large areas of mangroves have a significant number of 
protected areas, notably Australia (180), Indonesia (64) 
and Brazil (63). Conversely there are some, such as 



Equator 


■■ /' 


180° 


90°W il ^ 



Figure 3.1 The global distnbution ot mangroves 

In order to make the mangrove areas more visible, generalised outlines have been p: 
For more detailed information on actual mangrove area and distnbution see the maf 



Equator 


^^* /J r 


• 
180° 


90°W W ^ 



Figure 3.2 The global distribution of protected areas incorporating mangrove ecosystems. (Dat 




Bred. These greatly exaggerate the actual mangrove area. 
n the regional chapters. 




:rived from WCMC Protected Areas Database.) 



The Global Distribution of Mangroves 



25 



Nigeria, with very large areas of mangroves, which 
are notable in not having any of these within legally 
gazetted areas. 

Legal protection is, of course, only one tool for the 
conservation and sustainable use of mangroves. Fur- 
thermore, there are many cases where there is a lack 
of adequate management or insufficient resources to 
offer real 'on-the-ground' protection to these sites. 
Many other legal, industrial or traditional manage- 
ment regimes exist which are also used with consid- 
erable effect for the conservation and sustainable use 
of mangroves around the world. The regional tables 
and texts in this document provide a further, more 
detailed, overview of the management regimes oper- 
ating in many of the world's mangrove areas. 

The regional accounts 

Part 2 of this atlas takes five different regions of the 
world and presents a variety of data relating to those 
regions. Twenty-five regional maps are presented 
giving a detailed global map coverage of mangroves. 
Text and statistics accompany these maps. Each 
regional account begins with an introduction de- 
scribing the region in general terms. This is followed 
by a table showing the species of mangrove recorded 
from each country, together with references for this 
information. The text and tables consist mainly of 
individual country accounts. Finally, there are de- 
tailed case studies relating to the mapping of 
mangroves at a higher resolution. These cover eight 
sites in three different regions and provide an impor- 
tant insight into the techniques used for mapping 
mangroves. An understanding of these techniques is 
useful in understanding and correctly interpreting 
the regional maps. The case studies represent what 
can be achieved with the latest technology, given 
appropriate funding and a commitment to secure the 
best possible information. 

Regional maps 

Regional maps have been compiled on a country- 
by-country basis and a map reference is given for each 



country giving the details of the source material, 
together with further details where appropriate. The 
areas of mangrove have been calculated from the 
maps, although some caution is necessary in the 
interpretation of these figures. As already mentioned, 
a second figure entided 'alternative estimate of man- 
grove area' is also given for most countries. Where, in 
the Judgement of the editors, data from either source 
are considered to be of dubious value they are placed 
in parentheses. Such figures should not be quoted 
without the reservations being noted. 

The representation of very small mangrove areas is 
somewhat problematic, particularly in the coastal 
zone where the presentation of the coastline and 
rivers may further obscure the map. In areas where 
this has been deemed a problem, the overall area of 
mangrove has been slighdy exaggerated by means of 
surrounding the mangrove 'polygons' with a thick 
hne of the same coloration, even if the polygon is too 
small to show at the scale of printing, this surrounding 
hne should be sufficient to indicate the location. 
Where possible this technique has been kept to a 
minimum so that all mangrove areas are visible, but 
the total area of mangrove is still representative of the 
actual area of mangrove cover. Inset boxes are pro- 
vided for some of the most important areas, showing 
certain mangrove communities at greater resolutions. 

Species lists 

Species Usts have been compiled from a wide variety 
of sources and a single taxonomy of mangroves has 
been adopted from Duke (1992). Reference was also 
made to Tomlinson (1986) for queries relating to 
taxonomy and synonymy. Only three symbols have 
been used in the species tables: 

• Present 

I Introduced 

Ex Extinct (at the national level) 

In all cases the sources for the species Ust are 
provided. These source lists were reviewed by an 
international team of experts following their initial 
compilation. 



Table 3.2 A key to the sources and explanation of the figures provided in the country tables 



Land area 

Total forest extent 

Population 

GNP 

Mean annual temperature or temperature range 

Mean annual rainfall or average rainfall range 

Spring tidal range 

Alternative estimate of mangrove area 

Area of mangrove on map 

Number of protected areas with mangrove 



WRI (1994) 

WRI (1994) 

WRI (1994) 

WRI (1994) 

Same sources as text or Hunter (1994) 

Same sources as text or Hunter (1994) 

Typically taken from same sources as text 

Specified reference # 

Calculated from GIS system at the World Conservation Monitoring Centre 

(WCMC) # 

Derived from the WCMC Protected Areas Daubase Oegally gazetted sites in 

lUCN Management Categories I-V) 

Marked next to the total mangrove area considered, by the editors, to be the 

most reliable 



26 World Mangrove Atlas 

Country texts and tables 

Country texts and tables give an indication of the key 
features and issues relating to mangroves in each 
country. Where appropriate, or of particular interest, 
these may include information relating to key sites 
and features, forest structure, climate, salinity, tides, 
human uses (aquaculture, salt extraction, fisheries, 
forestry), threats, and conservation measures. The ref- 
erences used in the compilation of the text and 
statistics are provided at the end of each account. The 
tables contain standard information drawn from the 
sources shown in Table 3.2. 

Sources 

Duke, N.C. (1992). Mangroves floristics and 

biogeography. In: Tropical Mangrove Ecosystems. 

Robertson, A.I. and Alongi, D.M. (Eds). Coastal and 

Estuarine Studies 41. American Geophysical Union, 

Washington, DC. 329 pp. 
Field, CD. (Ed.) (1996). Restoration of Mart^rove 

Ecosystems. International Society for Mangrove 

Ecosystems, Okinawa, Japan. 250 pp. 
Fisher, P. and Spalding, M.D. (1993). Protected Areas 

vidth Mangrove Habitat. Draft Report. World 

Conservation Monitoring Centre, Cambridge, UK. 

60 pp. 
Hunter, B. (Ed.) (1994). The Statesman's Yearbook 

1994-95. 131st Edition. Macmillan Press Ltd, London, 

UK. 1709 pp. 
lUCN (1983). Global Status of Mangrove Ecosystems. 

Commission on Ecology Papers No. 3. Saenger, P., 

Hegerl, E.J. & Davie, J.D.S. (Eds). International Union 

for Conservation of Nature and Natural Resources, 

Gland, Switzerland. 88 pp. 
Ong, J. E. (1995). The ecology of mangrove conservation 

and management. Hydrohiotogia 295: 343-351. 
Toinlinson, P.B. (1986). The Botany of Mangroves. 

Cambridge University Press, Cambridge, UK. 413 pp. 
WRI (1994). World Resources 1994-95. A Guide to the 

Global Environment. Data Base Diskette and Users Guide. 

World Resources Institute, Washington, DC. 



Some Phytogeographical Considerations 



The widespread occurrence of mangrove vegetation 
and the floristic divergence between the 'old' and the 
'new' world mangroves, can only be explained by 
geological events, in that the composition of the 
modern mangrove flora at any one location, while 
subject to present-day climatic and geographical 
conditions, is largely relict (Tomlinson, 1986; Duke, 
1995). The present distribution of individual man- 
grove species must be seen against this background of 
plate tectonics and continental drift. Although several 
interpretations have been offered to relate mangrove 
distributions to past events (van Steenis, 1962; McCoy 
and Heck, 1 976; Specht, 1981; Mepham, 1 983; Duke, 
1995), none has been universally accepted. 

Each of these various interpretations is based on the 
existence, during the early Cretaceous, of an extensive 
tropical sea, the Tethys Sea, separating the northern 
supercontinent of Laurasia from the southern Gond- 
wanaland. Mangroves evolved within the Tethys Sea 
and dispersed outwards. Around 1 8 million years ago 
(mya), the western Tethys Sea became more or less 
enclosed, as the Mediterranean, by the collision of 
Africa and Asia Minor. At that time, the pantropical 
mangrove flora became disjunct and developed as two 
isolated floras (assuming that the southerly extensions 
of Africa and South America formed impassable 



barriers to mangrove dispersal). Around 3 mya, the 
Panama gap closed due to the collision of North and 
South America. Thus, today, there are three disjunct 
mangrove floras. However, the eastern Pacific flora 
IS too recent in origin to differ from its Atlantic 
progenitor. 

The prime areas of dispute concerning the phyto- 
geography of mangroves are the exact centre (s) of 
origin for mangroves and their subsequent dispersal 
routes around the various continents. Three broad 
views have been suggested: 

1 . An eastern Tethys Sea origin with dispersal across 
the Pacific and via the Panama gap into the 
Atlantic eastwards. 

2. An eastern Tethys Sea origin with dispersal north 
and westwards into the Atlantic and then via the 
Panama gap into the eastern Pacific. 

3. A western Tethys Sea origin with dispersal south 
via southern Africa to the eastern Tethys Sea. 

Each of these various interpretations is possible, 
although mangrove fossil records (Table 4.1), while 
somewhat ambiguous, generally support an eastern 
Tethys Sea origin and a westward dispersal via the 
Mediterranean route which, until about 18 mya, 
contained extensive Avkennia communities with Indo- 
Pacific affimty (Bessedik, 1981; 1985). 



Table 4.1 Significant geological events and mangrove fossil records 



Era 



Period 



mya Fossil record 



Cainozoic 



Pliocene 
Miocene 



3 
18 



10 





24 


Oligocene 


36 


Eocene 


40 



45 







.S4 


Palaeocene 




63 
69 


Mesozoic 


Creuceous 


110 



Panama route closed 

Tethys Sea route closed; Avicennia still present in 

Mediterranean 

Avicennia and Sonneratia pollen in Borneo; Avicennia pollen in 

Nigeria 

Rhizophora in Nigeria and South America 

Rhizophora pollen in Asia and Papua New Guinea 

Rhizophora, Avicennia and Sonneradd in southwest Austraha; 

first Rhizophora and Pellidera in Panama 

Fossils of Nypa, Ceriops, Palaeobruguiera and /4CTOsIic/iMm-like 

ferns in London Clay Flora 

Nypa pollen in Europe, Asia and Australia 

Nypa pollen in Nigeria 

Nypa pollen in Brazil 

First flowering plants 



28 



World Mangrove Atlas 



On the other hand, dunng the Palaeocene (63-55 mya) 
when the proto-Atlantic was a narrow waterway and 
western Africa was experiencing a 'wet' phase, there 
was no mangrove vegetation per se in the Niger Delta 
but extensive estuarine swamp communities doini- 
nated by Nypa. The eariiest Nypa pollen is recorded 
from Brazil and this genus apparently evolved in, and 
spread throughout, the proto-Atlantic at this time. 
This Nypa dominated swainp community remained 
in West Africa during the entire Eocene (Sowunmi, 
1981; 1986) and may have extended as far north as 
Europe (Wilkinson, 1981). 

Towards the end of the Eocene when seasonally dry 
conditions were widespread in West Africa, Nypa 
declined in abundance and finally disappeared alto- 
gether in the early Miocene (24 mya). At the same 
time Nypa disappeared from the fossil record of 
Venezuela. These disappearances coincided with the 
sudden and predominating appearance oi Rhizophora 
throughout the region. Thus, at least one mangrove 
apparently evolved in the western Tethys Sea (the 
proto-Adantic) and dispersed out of the region while 
selected members of the eastern Tethys Sea (Indo- 
Pacific) mangrove flora were able to enter and survive 
in the proto-Atlantic before the Tethys Sea (Mediter- 
ranean) became unavailable as a migration route. 

Whatever the exact origin(s) and dispersal routes of 
mangroves, the present distributions of mangroves 
show many interesting features and can be used to 
illustrate a number of biogeographic processes. The 
remainder of this section considers a number of these 
features and processes in more detail. 

Discontinuities and endemism 

Most mangroves (e.g. Maps 4.5-4.13 and 4.26 - 4.32) 
have a more or less continuous distribution but there 
are exceptions. 

Sonneratia alba appears to have several disjunct 
populations respectively centred on East Africa/ 
Madagascar, India/Sri Lanka and Australasia (Map 
4.7). Even the northern Australian distribution ap- 
pears to be separated by a significant discontinuity in 
the Gulf of Carpentaria. 

Sonneratia ovata has a major disjunction between 
the Thai-Indonesian and the Papua New Guinea 
occurrences (Map 4.16). Similarly, Sonneratia larueo- 
lata appears to have three discontinuous distributions 
(Map 4.15). 

Avicennia rumphiana appears to be the only species 
oi Avicennia with three disjunct distributional ranges 
(Map 4.14). 

Bruguiera hainesii is discontinuous between western 
Malaysia and New Guinea (Toinlinson, 1986). 

Rhizophora apiculata also appears to be discontinu- 
ous in that the Indian-Sri Lankan distribution is 
separated from the Southeast Asian distribution by the 
extensive gap comprising the entire Gulf of Bengal 
(Map 4.9). The 'new world' species of Rhizophora also 



show disjunct distributions with West African, 
Adantic American and Pacific American occurrences 
(Maps 4.28, 4.30 and 4.31). In the case of Rhizophora 
mangle (Map 4.28), even the West African distribution 
appears to be disjunct with a Senegal to Liberia and 
a Nigeria to Angola distribution (Saenger and Bellan, 
1995). 

Pelliciera rhizophorae is of very limited distribution 
and endemic to the tropical Pacific coast of America 
(Map 4.24). While fossil records of this species have a 
much wider Caribbean distribution, this species is 
endemic over a very limited range. Its presence on the 
Caribbean coasts, first noted in the early 1980s, is of 
uncertain origin (see below). 

Other locally restricted species include Heritiera 
fomes (Map 4.17), Aegialitis rotundijolia (Map 4.1), 
Avicennia Integra (Map 4.22), Avicennia bicolor (Map 
4.23), Avicennia schaueriana (Map 4.25), Excoecaria 
ovalis (Map 4.21), Excoecaria indica (Map 4.20), 
Sonneratia griffithii (Map 4.18) and Sonneratia apetala 
(Map 4.19). 

The explanations for many of these disjunctions 
are undoubtedly to be found in the ecological re- 
quirements of the individual species but, in a broad 
biogeographical sense, temperature and rainfall are 
probably the main determinants. Nevertheless, the 
high endemicity of the south Asian and northern 
Australian areas may reflect their proximity to one of 
the centres of mangrove origin and subsequent dis- 
persal routes. 

Vicariants 

Being seawater dispersed, there are few examples of 
divergent species of one genus with non-overlapping 
ranges. However, such vicariant species are found 
in Aegialitis and Camptostemon (Toinlinson, 1986). 
Aegialitis annulata (Map 4.2) is distributed firom north- 
ern Australia to Papua New Guinea while Aegialitis 
rotundijolia (Map 4.1) is restricted to shorelines of the 
Bay of Bengal and the Andaman Sea. Similarly, 
Camptostemon schultzii occurs in northern Australia, 
Papua New Guinea and, possibly, as far north as 
Borneo while Camptostemon philippinense occurs in 
the PhiUppines, Borneo and Sulawesi. Whether there 
is any overlap between these species in Borneo is not 
known. 

By way of contrast, the genus Aegiceras contains 
one species {Aegiceras corniculatum) with a wide Aus- 
tralasian distribution which totally includes the more 
restricted Philippine distribution of Aegiceras Jloridum 
(Maps 4.3 and 4.4). 

Hybridisations 

Hybrids are known between several species of man- 
groves including Sonneratia, Rhizophora, Xylocarpus and 
Lumnitzera (Duke and Bunt, 1979;Duke, 1984; Tom- 
linson, 1986) which suggests that the genetic isolation 
between species of some genera is not complete. 



Some Phytogeographical Considerations 



29 



Plant introductions 

As with other plant groups, mangroves have been 
deliberately introduced into areas beyond their natu- 
ral distributional ranges to meet human needs. While 
some of these introductions are well documented, 
other are not and are likely to affect apparent distribu- 
tional ranges. 

Thus, the present West African populations ofNypa 
fruticans were introduced to Calabar in 1906 and Oron 
in 1912 (Wilcox, 1985) from the Singapore Botanic 
Gardens even though this species had occurred 
throughout the Niger Delta until 25 mya (Sowunmi, 
1986). To date, this species has spread into the Niger, 
Imo, Bonny and Cross Rivers and its rate of spread 
is perceived to be accelerating over recent years. It 
has now reached the Wouri Estuary in Cameroon 
where its dispersal is facilitated by local villagers who 
value its thatching properties (Din, 1991). Intro- 
duced stands of Nypa fruticans have also recently 
been recorded from the Atlantic coast of Panama, 
where a similar spread is predicted (Duke, 1991). 

Even though Pelliciera fossils indicate their presence 
in the Caribbean during the Eocene, the present 
populations o( Pelliciera rhizophorae on the Caribbean 
coasts of Panama and Colombia have a questionable 
origin. This species has been introduced from the 
Pacific to the Adantic coast of Colombia, around the 
Canal del Dique y Covenas, in the last twenty years 
(Paez, 1 994) although apparently ancient stands occur 
on the Adantic coast of Panama (Duke,pers. comm.). 

An extreme example of the extension of the 
distribution of species is the introduction and estab- 
lishment of Rhizophora mangle, Rhizophora mucronata, 
Bruguiera parvijlora and Bruguiera sexangula on Oahu, 
Hawaii around the turn of this century. 

Floristic decline 

Superimposed onto historical events are present con- 
straints of chmatic, geographical and socio-economic 
conditions. These constraints are manifested by a 
reduction of species with increasing latitude or aridity 
on the one hand, and selective removal or loss of 
species by human activity on the other. 

Latitudinal limits 

The latitudinal limits of mangroves on each of the 
major land masses (Table 4.2) show these Umits to be 
quite variable and broadly related to temperature and 
aridity. 

In addition, these latitudinal Mmits are preceded by 
a gradual attenuation of species with increasing lati- 
tudes. For example, Saenger and Moverley (1985) 
have suggested that in the presence of an adequate 
rainfall (as on the eastern coast of Australia), tempera- 
ture is the major factor in reducing species abundance 
with latitude, and good correlations between the 
temperature optima of species and their geographical 
distributions were found. 



Table 4.2 Latitudinal Umits of mangroves on 

major land masses 



Continental 


Northern 


Southern 


land mass 


limit 


limit 


Atlantic America 


32-20' 


28- 56' 


Pacific America 


3(yi!5' 


.■i-32' 


Atlantic Africa 


19- .SO' 


12-20' 


Eastern Africa/Red Sea 


27- 40' 


32- .S9' 


Western Australia 


- 


33-16' 


Eastern Australia 


- 


38*45' 


Pacific Asia 


31-22' 


- 



Aridity 

The latitudinal limits of mangroves on the West 
African and South American Pacific coasts, as shown 
in Table 4.2, coincide with the hmits of arid regions 
(UNESCO, 1979) (defined as: summer rainfall and 
winter drought, 12 months/year with <30 mm 
rainfall, and a precipitation to potential evapotran- 
spiration ratio (P/PEt) <0.03). This suggests that, as 
found on other western coasts of continents (e.g. 
Australia), mangrove distribution on these coasts is 
more limited by aridity than by temperature. Similar 
considerations would also be relevant to parts of 
West Asia and the Middle East. This influence is 
clearly seen in the broader latitudinal ranges of 
species on the eastern coasts of the Americas than 
those on the western coasts (Maps 4.27-4.32). 

Human-induced distributional changes 

Human activity (such as pollution, water diversion 
and selective clearing) can significantly change man- 
grove distributional ranges. Thus, the northernmost 
stands oi Rhizophora racemosa in West Africa, reported 
by Adam (1965) from the ile de Thiong (16°03'N), 
Mauritania, have been cleared by the local inhabitants 
in the last two decades (Gowthorpe and Lamarche, 
1993). Similarly, significant stands of Bruguiera gymnor- 
rhiza have been selectively felled for boat building in 
Yemen while Rhizophora mucronata has virtually 
disappeared from the Gulf for similar reasons in 
historical time. Elsewhere, the construction of dams 
and barrages has shifted prevaihng sahnity regimes to 
the exclusion of one species over another. 

Conclusion 

In conclusion, there are a number of poorly under- 
stood historical as well as current factors imphcated 
in the biogeography of mangrove communities and 
species. Most importandy, the maps of present day 
mangrove distributions are based on incomplete data 
for considerable areas of the world. This is a situation 
that must be addressed urgendy if the information is 
not to be lost. 



30 



World Mangrove Atlas 



Sources 

Adam.J.-G. (1965). La vegetation du delta du Senegal 

en Mauritanie - le cordon littoral et I'lle de Thiong. 

Bull, de I'l. F.A.N. 27: 121-138. 
Bessedik, M. (1981). Une mangrove a Avicennia L. en 

Mediterranee occidentale au Miocene infirieur et 

moyen. Implications Paleogeographiques. C.R. Acad. Sc. 

(Paris) 293: 469-472. 
Bessedik, M. (1985). Reconstruction des 

Environnements Miocenes des Regions Nord-Ouest 

Mediterraneenes a Partir de la Palynologie. Unpubl. 

Thesis, L'Universite des Sciences et Techniques du 

Languedoc, Montpellier, France. 
Din, N. (1991). Contribution a L'etude Botanique et 

Ecologique des Mangroves de L'estuaire du 

Cameroun. Unpubl. Thesis, Umversite de Yaounde, 

Yaounde, Cameroun. 
Duke, N.C. (1984). A mangrove hybrid, Sonneratia x 

gulngai (Sonneratiaceae) from north-eastern Australia. 

Austrobaikya 2: 103-105. 
Duke, N.C. (1991). Nypa in the mangroves of Central 

America: introduced or relict? Principes 35: 127-132. 
Duke, N.C. (1995). Genetic diversity, distributional 

barriers and rafting continents - more thoughts on the 

evolution of mangroves. Hydrobiologia 295: 167-181. 
Duke, N.C. and Bunt,J.S. (1979). The genus Rhizophora 

(Rhizophoraceae) in north-eastern Australia. Aust.J. 

Bot. 27: 657-678. 
Gowthorpe, P. and Lamarche B. (1993). Les mangroves 

de la Mauritanie. In: Conservation et Utilisation 

Rationnelle des Forets de Mangrove de I'Amerique Latine et 

de I'Afrique. Diop, E.S., Field, CD. and Vannucci, M. 

(Eds). Dakar, 20-22 January, 1993. ITTO/ISME 

Project PD114/90 (F). pp. 3-21. 
McCoy, E.D. and Heck, K.L. (1976). Biogeography of 

corals, seagrasses, and mangroves: an alternative to the 

center of origin concept. Sysl. Zool. 25: 201-210. 
Mepham, R.H. (1983). Mangrove floras of the southern 

continents. Part I, The geographical origin of 

Indo-Pacific mangrove genera and the development 

and present status of Australian mangroves. South Afr.J. 

Bot. 2: 1-8. 
Paez, H.S. (1994). Los manglares de Colombia. In: El 

Ecosistema de Manglar en America Latina y la Cuenca del 

Caribe: su Manejo y Conservacion. Suman, DO. (Ed). 

The Tinker Foundation, New York, USA. pp. 21-33. 
Saenger, P. and Bellan M.F. (1995). The Mangrove 

Vegetation of the Atlantic Coast of Africa. Universite de 

Toulouse Press, Toulouse, France. 
Saenger, P. and Moverley, J. (1985). Vegetative phenology 

of mangroves along the Queensland coastline. Proc. 

Ecol. Soc. Aust. 13: 257-265. 
Sowunmi, M.A. (1981). Late quaternary envirotunental 

changes in Nigeria. Pollen et Spores 23: 125-148. 
Sowunmi, M.A., (1986). Change of vegetation with 

time. In: Plant Ecology in West Africa. Lawson, G.W. 

(Ed.). John WUey & Sons, Chichester, UK. 

pp. 273-307. 



Specht, R.L. (1981). Biogeography of halophytic 

angiosperms (salt-marsh, mangrove and seagrass). In: 

Ecological Biogeography of Australia. Keast,A. (Ed.).W. 

Junk, The Hague, The Netherlands, pp. 577-589. 
van Steenis, C.G.GJ. (1962). The distribution of 

mangrove plant genera and its significance for 

palaeogeography. Proc. Kon. Net. Amsterdam, Ser C 

65: 164-169. 
Tomlinson, PB. (1986). The Botany of Mangroves. 

Cambridge University Press, Cambridge, UK. 413 pp. 
UNESCO (1979). Map of the world distribution of arid 

regions: explanatory note. MAB Technical Notes 7. 

54 pp. 
Wilcox, B.H.R. (1985). Angiosperm flora of the 

mangrove ecosystem of the Niger Delta. In: The 

Mangrove Ecosystem of the Niger Delta. Wilcox B.H.R. 

and Powell C.R (Eds). Proceedings of a workshop. 

University of Port Harcourt, Port Harcourt, Nigeria. 

pp. 34-44. 
Wilkinson, H. P. (1981). The anatomy of the hypocotyls 

of Ceriops Arnott (Rhizophoraceae), recent and fossil. 

Bot.f Unn. Soc. 82: 139-164. 

Authorship 

This section was kindly supplied by Peter Saenger and 
G. Luker, Centre for Coastal Management, Southern 
Cross University, Lismore, New South Wales, Australia. 



Some Phytogeographical Considerations 



31 





Map 4.1 Aegialitis rotundifolia 



Map 4.2 Aegialitis annulata 




Map 4.3 Aegiceras corniculatuin 




Map 4.4 Aegiceras floridum 



32 



World Mangrove Atlas 




Map 4.5 Avicennia iiiaiiiia 




Map 4.6 Rhizophora mucronata 




Map 4.7 Sonneratia alba 



Some Phytogeographical Considerations 



33 




Map 4.8 Sonneratia caseolaris 




Map 4.9 Rhizoplwra apiculata 




Map 4.10 Rhizophora stylosa 



34 



World Mangrove Atlas 




Map 4.11 Avicennia alba 




Map 4.12 Avicennia officinalis 




Map 4.13 Bruguiera sexangula 



Some Phytogeographical Considerations 



35 




Map 4. 14 Avicennia rumphiana 




Map 4.15 Soiinercitia lanceolata 




Map 4.16 Sotnieratia ovata 



36 



World Mangrove Atlas 



\ /^ 


r\ 




yo 


H 






I. 


0- 


^^ 


^ 


/W' 








90'E 


M„ 


11^ 




Map 4.17 Heritiera foines 



Map 4.18 Sonneratia grijfithii 




Map 4.19 Sonneratia apetala 



Map 4.20 Excoecaria indica 




Map 4.21 Excoecaria ovalis 



Map 4.22 Ai'icennia Integra 



Some Phytogeographical Considerations 



37 





Map 4.23 Avicennia hicolor 



Map 4.24 Pelliciera rhizoplu 




Map 4.25 Avicennia schaneriana 




Map 4.26 Kaiidelia candel 



38 



World Mangrove Atlas 




Map 4.27 La^iinailaria raceiitosa 




Map 4.28 Rliizopliora mangle 




Map 4.29 Avicennia germinans 



Some Phytogeographical Considerations 



39 




Map 4.30 Rliizopliora raceniosa 




Map 4.31 Rhizophora lumisonii 




Map 4.32 Conocarpus erectus 






Part 2 



I 



Regional 
Mangrove Distributions 



«-» 



%t: 



0t 



f-^- 



jgSSjLjT'' 



South and Southeast Asia 



This region stretches from Pakistan in the west to China and Japan in the northeast, and includes insular 
Southeast Asia to Irian Jaya (Indonesia) in the southeast. The mangroves of South and Southeast Asia have been 
described in some detail by a number of authors (Clough, 1993; Umali et a/., 1986; ISME, 1994; Scott, 1989; 
and Collins et a/., 1991). Table 5.1 gives a hst, by country, of the mangrove species found in this region. South 
and Southeast Asia have some of the largest areas of mangroves in the world. The total area of mangrove in the 
region is some 75,173 sq km, which represents some 42% of the total area of mangroves in the world. 

The total length of coastUne in the region is considerable, due to the very large number of islands in Southeast 
Asia. Over most of the region, coastlines are relatively sheltered and typified by relatively high rainfall with 
considerable riverine input. Tropical cyclones present a threat to some coastlines and can cause them considerable 
damage, particularly in the northern and western Bay of Bengal, the Philippines, north Vietnam and China. The 
role that mangroves can play in mitigating this damage has been recognised in a number of countries. 

The region has the highest diversity of mangrove species in the world. Many authors consider the 
Indo-Malayan region to be the major centre of origin for mangrove taxa, and that dispersal from here to other 
areas occurred particularly during the Tertiary and Quaternary. A high diversity of associated plant and animal 
life is also found in the mangrove areas. 

Traditional uses of the mangroves can be traced back many centuries and include widespread use for timber, 
thatching materials, fiielwood, charcoal and fodder. The high diversity of species is paralleled by a wide range 
of traditional medicinal uses in all countries. In Indonesia and Kerala (southwest India) the development of 
brackish water ponds for aquaculture can also be traced back for several centuries. This century the utihsation 
of the mangrove forests has developed in this region more than in any other. Capture fisheries and raft, cage 
and bottom culture fisheries have developed and, more recendy still, pond-based aquaculture systems have 
increased and intensified. The latter has usually been to the detriment of wide areas of mangrove. Burgeoning 
populations and considerable economic growth have created conditions for widespread mangrove exploitation 
and ftirther areas have been lost as a result of timber extraction, conversion to agriculture, reclamation for urban 
and industrial development, or simple degradation from excessive fiielwood extraction, waste dumping or 
pollution. 

In many countries there is a growing awareness of the importance of mangroves, and since the 1970s National 
Mangrove Committees have been estabhshed within government departments in many countries. Sustainable 
forestry is being encouraged and appears to be working successfially in a number of sites. Bangladesh and Vietnam 
have been undertaking large mangrove afforestation and re-afforestation programmes for at least 1 5 years, with 
similar, though smaller, operations occurring in other countries. 



44 



World Mangrove Atlas 



Table 5.1 Mangrove species list for South and Southeast Asia 





E 

CD 


£ 

to 
Q 

Qi 

c 

CO 


.5 

f 


c 

i 

■D 

C 
ro 
ro 

C 


c 

2 

c 
o 

X 


c 


(3 

QJ 

C 


TO 

c 
o 

C 


c 


TO 

1 

fD 

2 


E 

c 

2 


c 
to 


OJ 

Q. 
Q. 

Q- 


QJ 
O 

a 

a 

c 
in 


fD 

c 

fD 


T3 

C 
_fO 

I— 


E 

fO 

c 

(U 

> 


Acanthus ebracteatus 




• 




• 






• 












• 


• 




• 


• 


Acanthus ilicifolius 


• 


• 




• 


• 


• 


• 












• 


• 


• 


• 


• 


Acrostichum aureum 


• 


• 




• 




• 


• 




• 




• 




• 


• 


• 


• 


• 


Acrostichum speciosum 




• 




• 




















• 




• 




Aegialitis annulata 




































Aegialitis rotundifolia 


• 












• 


















• 




Aegiceras corniculatum 


• 


• 




• 


• 


• 


• 










• 




• 


• 


• 


• 


Aegiceras floridum 


































• 


Avicennia alba 


• 


• 








• 


• 














• 




• 


• 


Avicennia marina 


• 


• 




• 


• 


• 


• 




• 






• 




• 


• 


• 


• 


Avicennia officinalis 


• 


• 








• 


• 














• 


• 


• 


• 


Avicennia rumphiana 




































Bruguiera cylindrica 




• 




• 




• 


• 














• 


• 


• 


• 


Bruguiera exaristata 




































Bruguiera gymnorrhiza 




• 


• 


• 


• 


• 


• 




• 










• 


• 


• 


• 


Bruguiera hainesii 
































• 




Bruguiera parviflora 




• 








• 


• 














• 




• 


• 


Bruguiera sexangula 


• 


• 




• 




















• 


• 


• 


• 


Camptostemon philippinense 




































Camptostemon schultzii 




































Ceriops decandra 


• 










• 


• 
















• 


• 


• 


Ceriops tagal 


• 


• 




• 




• 


• 










• 




• 


• 


• 


• 


Cynometra iripa 
































• 




Dolichandrone spathacea 




• 
























• 


• 


• 


• 


Excoecana agallocha 


• 


• 




• 


• 


• 


• 




• 










• 


• 


• 


• 


Excoecaria indica 


• 


























• 








Heritiera fomes 


• 












• 








• 










• 




Heritiera globosa 




• 
































Heritiera littoralis 


Ex 


• 




• 






• 




• 








• 


• 


• 


• 


• 


Kandelia candel 


• 


• 




• 


• 


• 


• 




• 




• 






• 




• 


• 


Lumnitzera littorea 




• 




• 






• 














• 




• 


• 


Lumnitzera racemosa 




• 




• 




• 


• 




• 










• 


• 


• 


• 


Lumnitzera x rosea 




































Nypa fruticans 


• 


• 


• 


• 






• 




• 




• 






• 


• 


• 


• 


Osbornia octodonta 




































Pemphis acidula 


















• 










• 


• 


• 




Rhizophora apiculata 


• 


• 


• 






• 


• 








• 






• 


• 


• 


• 


Rhizophora mucronata 


• 


• 


• 


• 




• 


• 








• 


• 




• 


• 


• 


• 


Rhizophora stylosa 








• 










• 










• 






• 


Rhizophora x lamarckii 














• 






















Scyphiphora hydrophyllacea 




• 




• 




















• 


• 


• 


• 


Sonneratia alba 




• 




• 




• 


• 




• 










• 


• 


• 


• 


Sonneratia apetala 


• 










• 


• 








• 








• 






Sonneratia caseolaris 


• 


• 


• 


• 




• 


• 








• 




• 


• 


• 


• 


• 


Sonneratia griffithii 














• 








• 










• 




Sonneratia lanceolata 




































Sonneratia ovata 




• 




• 




















• 




• 


• 


Sonneratia x gulngai 




• 
































Sonneratia x urama 




































Xylocarpus granatum 


• 


• 




• 




• 


• 








• 




• 


• 


• 


• 


• 


Xylocarpus mekongensis 


• 




















• 






• 




• 





Ex Extinct in that country 



South and Southeast Asia 



45 



Bangladesh 



Map 5.2 



Land area 144,000 sq km 

Total forest extent ( 1 990) 7,690 sq km 

Population ( 1 995) 1 28,25 1 ,000 

GNP(1992) 220 US$ per capita 

Mean monthly temperature range (Chittagong) 19-27°C 

Mean annual rainfall (Chittagong) 2,831 mm 

Spring tidal amplitude 3.4 m 

Alternative estimate of mangrove area (Siddiqi, pers. comm., 1995) 6,343 sq km 

Area of mangrove on the map 5,767 sq km# 

Number of protected areas with mangrove 4 

Bangladesh has one of the largest areas of river delta in the world, formed by the Ganges, Brahmaputra and 
Meghna Rivers. It also has, probably, the largest continuous area of mangroves in the world, the Sundarbans 
mangrove forest, which extends across the border with India. This is surprising for a country with one of the 
highest human population densities m the world. In addition to the Sundarbans, a smaller natural area of 
mangroves, the Chokoria Sundarbans, is located in the east of the country in the delta of the Matamuhuri River. 
This area covered 750 sq km m 1975, but is now less than 10 sq km. Most of this destruction was due to 
clearance of mangroves for shrimp farms. There are a few scattered areas of natural mangrove between these 
two larger areas, while significant additional areas are covered by mangrove plantations. The high degree of 
riverine sediments, combined with the regular impact of cyclones along the coast, provide a highly dynamic 
coastUne, with the constant appearance of newly accreted land. 

Mangroves are an extremely important natural resource to the ten million people living in the coastal zone. 
Mangrove wood is widely used for timber and fuel; apiculture is an important industry, yielding thousands of 
tons of honey and wax each year; shrimps, crabs, molluscs and finfish are taken from the surrounding waters. 
In 1983 some 160,000 people were employed in fishing alone. 

Cyclones cause considerable damage in Bangladesh, mostly from storm surges, and 140,000 people were 
killed in the cyclone of 1991. The role of the mangroves in protecting large parts of the coast has long been 
recognised, and this has been one of the reasons behind the development of large mangrove afforestation 
schemes. More than 1,200 sq km of mangroves have been planted, since 1966. 

The Sundarbans were declared a Reserved Forest in 1875. They remain heavily utilised, with regular timber 
harvesting. Parts of the Sundarbans have the designation of Wildlife Sanctuary. They are very important for 
waterfowl, tigers, deer, monkeys, the Ganges River dolphin, two species of otter, wild cats and the estuarine 
crocodile. 

Map reference 

Information for the Sundarbans was denved from World Bank (1981), itself derived from updated and ground-truthed 
1977 Landsat satellite imagery. Additional areas are largely plantation forest, taken from a detailed sketch map prepared 
for this work by N.A. Siddiqi, Bangladesh Forest Research Institute, drawn onto a 1:1,000,000 base map. 

World Bank (1981). Bangladesh-General Vegetation. Sheet No. G8, 1:500,000. Prepared by the Resource Planning Unit, 
Agriculture and Rural Development Department, World Bank, Washington. 



Country sources 


for Table 5.1 








Bangladesh 


Choudhury eta/., 1993; Scott 1989 


Japan 


Baba, 1994 




Seidensticker eta/., 1983; Siddiqi, 1986 


Malaysia 


Chan, 1986 


Brunei Darussalam 


Zamora, 1987, 1992 




Myanmar 


Htay, 1994 


Cambodia 


Sin, 1990 




Pakistan 


Qureshi and Duke, pers. comm., 1995 


China and Taiwan 


Davie, 1989 




Philippines 


Philippine National Mangrove Committee, 1 986 


Hong Kong 


Scott, 1989 




Singapore 


Corlett, 1986 * 


India - west 


Untawale, 1986 




Sri Lanka 


Jayewardene, 1 986 


India • east 


Untawale, 1986 




Thailand 


Aksornkoae ef a/, 1993 


Indonesia 


Soemodihardjo et al., 


1993 


Vietnam 


Hong and San, 1993 



* Although a species list is provided for Singapore this is based on relatively old data and it is likely that many of these species have now 
been lost from this country 



46 World Mangrove Atlas 

Brunei Darussalam Maps.? 

Land area 5,770 sq km 

Population (1995) 288,000 

Mean monthly temperature range 27-28°C 

Mean annual rainfall 2,800 mm 

Spring tidal amplitude 2 m 

Alternative estimate of mangrove area (Zamora, 1992) 184 sq km 

Area of mangrove on tfie map 171 sq km# 

Number of protected areas with mangrove 1 

Due to a lack of human pressure which is probably related to the wealth of the country, the mangroves of 
Brunei Darussalam are among the best preserved m Southeast Asia. Most are deltaic, estuarine and fringe 
formations, with the largest concentrations around the Brunei estuary, but they are also found along the Belait 
and Tutong Rivers. For the most part the forests are very diverse, but some are dominated by single species, 
notably areas of Rhizophora apiculata or Nypafruticans. Uses are relatively limited, but there is some use for poles 
and pilewood in construction; and there is a small and decreasing use for charcoal production. Crab and shrimp 
fisheries are also linked to the mangroves. Well over 50% of the total mangrove area is set aside for preservation, 
conservation and environmental protection, a further 75 sq km have been assigned for timber production, which 
may be sustainable, while only 2 sq km are being converted to other uses, mostly urban development. 

Map references 

Data extracted from a 1:25,000 coastal sensitivity map (Fisheries Department/Shell, 1992). 

Fisheries Department/Shell (1992). Coastal Environmental Sensitivity Mapping of Brunei Darussalam. A joint project of 
Fisheries Department, Ministry of Industry and Primary Resources and Brunei Shell Petroleum Company Sdn Bhd. 
Unpublished report, August, 1992. 40 pp + 1:250,000 map. 

Cambodia Map 5.2 

Land area 181,040 sq km 

Total forest extent ( 1 990) 1 2 1 ,630 sq km 

Population (1995) 9,447,000 

GNP(1991) 200 US$ per capita 

Mean monthly temperature range 25-29°C 

Mean annual rainfall 1,875 mm 

Alternative estimate of mangrove area (Mekong Secretariat, 1994) 851 sq km# 

Area of mangrove on the map 601 sq km 

Number of protected areas with mangrove 

Mangroves are found along the coast in a number of places but are most heavily concentrated in the north 
around the estuarine and lagoon complex of the Koh Pao and Kep Rivers and in the Koh Kong Bay (160 sq km). 
They are largely absent from the central part of the coastline where the shore is rocky, but are also found in 
the south of the country towards Vietnam. Mangroves are used for firewood and charcoal for domestic 
consumption, which has reduced mangroves in some areas to shrubs of low value. Some areas have been 
reclaimed for agriculture. Aquaculture remains insignificant, and population pressure in the coastal areas is not 
high. During the Khmer Rouge regime all conservation and forestry activities ceased, and although conservation 
has become important since then, there are no proposals for the protection or active management of the 
mangrove areas. Calculations of the mangrove area based on Landsat imagery (1992/93) show a much larger 
area than the figure provided by Sin (1990) of 370 sq km. The former suggests that the mangrove area has 
increased since 1 985-87 by nearly 25%. These differences could be an artefact arising from image interpretation. 

Map references 

Data were digitised from Mekong Secretariat (1991) which is based on 1988/9 Landsat TM images interpreted without 
ground-truthing. More recent maps (Mekong Secretariat, 1994), showing mangroves (c. 1:400,000 to 1:1,000,000) are 
now available - differences in the mangrove coverage between these two sources are not significant at the scales used for 
this adas. 

Mekong Secretariat (1991). Reconnaissance Landuse Map of Cambodia. 1:500,000. Mekong Secretariat, Bangkok, Thailand. 
Mekong Secretariat (1 994). CrtmfcodiaLrtnrfCowry4(/(is 1985/87 - 1992/93 (including national and provincial statistia). Remote 

Sensing and Mapping Unit, Mekong Secretariat; United Nations Development Programme; Food and Agriculture 

Organisation, Cambodia. 124 pp. 



South and Southeast Asia 



47 



Case study 



Mangroves of the Ganges and Brahmaputra Deltas 

The area around the Ganges and Brahmaputra Deltas includes the largest single area of mangroves 
of the world, the Sundarbans, with a total extent of dense tidal forest of some 6,050 sq km shared 
between India (2,000 sq km in West Bengal State) and Bangladesh (4,050 sq km). These 
mangroves, located at the north of the Bay of Bengal, are directly exposed to tropical cyclones 
(Figure 5.2). The high winds and tidal surges associated with the cyclonic storms often disturb 
natural zonation patterns in the mangrove ecosystem, influencing the structure and the morphology 
of forest stands. Moving south from this area, mangrove ecosystems are usually protected in creeks 
and bays and are less exposed to cyclonic storms (see The Cauvery Delta (Pichavaram) case study). 

A further major natural influence on these ecosystems can be related to plate tectonics. These 
are responsible for the general tilting of this large delta, which is more than 200 km east to west, 
causing a slow rising of the western (Indian) part, gradually displacing the main course of the Ganges 
eastward. The main deltaic region and highest levels of freshwater runoff are now restricted to 
Bangladesh where the salinity of water and soil is thus lower. The eastward displacement of the 
Ganges has had a considerable effect on the mangroves of India, increasing salinities in the soils 
and reducing the input of nutrient-rich alluvium. Relating to this, a gradation can be observed in 
both the size and physiognomy of the mangroves across this area. In the east, in Bangladesh, trees 
form a tall dense forest of about 15 m in height where valuable species like Heritiera fomes and 
Niipa fruticans are common. In the west, in India, less salt-tolerant taxa (Heritiera, Niipa) arc 
rare, while low stands of bushy species such as Excoecaria agallocha, Aegiceras corniculatum 
and Phoenix paludosa are common. 

Anthropogenic effects on these ecosystems are considerable. Firstly, there is indirect damage 
caused by the construction of embankments and dams upstream of mangrove areas which is likely 
to induce ecological and biological modifications. This is probably the cause of the phenomenon 
of mangrove 'top dying' in Bangladesh. Secondly, there is the huge coastal afforestation programme 













Figure 5. 1 False colour composite of NOAA, AVHRR and LAC channels 

1 Hatia 2 Ambaria 3 Sella FJiver 



48 



World Mangrove Atlas 



in Bangladesh, resulting in the creation of pure stands of Sonneratia apetala. More than 
150,000 ha having already been planted. Thirdly, the population in this region of Bangladesh and 
India is one of the most dense in the world with over 1 ,000 people per sq km. This dense population 
places considerable pressure on mangrove ecosystems so that, for example, during the first half of 
the twentieth century about 600 sq km of mangroves forests were disturbed and converted to 
agriculture, mainly rice fields. 

The diagrams and figures presented here show the mangroves of the region and an individual 
site on Hatia Island. In the former it is quite clear that even a relatively low resolution remote sensing 
system like NOAA-AVHRR can show large mangrove areas, while SPOT and aerial photography 
allow considerable refinement. For SPOT, small images and high processing times typically 
preclude the use of these in the preparation of maps covering very large areas at the current time. 
Using a time series, even if images were taken with different media, it is possible to observe changes 
in mangrove area, zonation and areas of erosion and accretion. 



Environmental data 

• Mean annual rainfall 

• Dry season 

• Cyclonic storms 

• Riverine input 

• Mean water salinity 

• Dominant soil types 

• pH of the topsoil 

• Average tidal amplitude 

• Average population density 

• Total areal extent 

• Dominant mangrove types 

• Main mangrove species 



1,500-2,000 mm/year 

4-6 consecutive dry months (November to April) 

High frequency 

From the Ganges and Brahmaputra, with a very large catchment area 

25 to 32%oon the western part; 10 to 20%oon the east 

Loamy-clay (surface) 

7 to 8 

3-6 m 

>500 people per sq km 

6,050 sq km 

All types except the Rhizophora riverine (Curtis, 1933; Blasco, 1975) 

Heritiera forr\es, Sonneratia apetala, Excoecaria agallocha, 

Auicennia officinalis, Ceriops decandra, Nypa fruticans 




^"^^ Natural mangrove 



fy-y-. High cyclone 

V/Z frequency 

^'^ (August-September) 



Low cyclone 
^ frequency 

(October-November) 



Figure 5.2 Cyclonic tracks in the Bay of Bengal and location of mangroves 



South and Southeast Asia 



49 



f 

I 




a - From aerial photos 1981 





T^ 




f i.y. 




J 




f »/•/ 




/ 


NE*Pl.*KT*TlW_f y^L^ 


COAJtAL DIOSKK— * 


I 




VSaoaut 


/ 1 




«* Wjv/taix»j// 


A 


CC5THUCTID / J 




J-r f^~^ 


f 


WAHCROVI ^^J J 






(PwEAXC 














f«ILY 








Di-i 'bULIUJ 








1»n«XIH 










""^1 Y / 




jC^ ^—^■"1^5^ CDASTALaOJO* 


/^ V / 




/J^^^ / 




M^^ \ 


^ 






fo "/ \.r-r'T— 




(0 ***2^^F^ 




^g^ «WfU*K»JiaH 




^^2/ 




COASTA^v ") 


^ ' 


^^^ 




eWB)QH"^\.^^ /"'^ 


^f>. 






a\^ ^\S»^r ■"'''^*- 








Y 














(I e * ^S"*-;! *5^ 








a " " ^*/ACCROiOf 
























•1^^ 


r 


§ 












^ -»" 






1 


2 km 

_J 


b - Prom SPOT data (25 february 1987) 





Embankment 



Afforested 
r-^ — ] mangrove 
I- I (Sonneratia) 



E3^ 



Grasses 
Porteresia) 



l:"Ss^ Sand 



Evolution of south Hatia coastal area; interpretation of satellite data 

This time-series comparison, undertaken with the superimposition of aerial photographs and 

satellite data (using Didactim software) clearly shows: 

- a conspicuous area of erosion in the southeastern part of Hatia Island 

- a conspicuous area of accretion in the western comer of the image 

- the notable resistance of newly planted mangrove trees to cyclonic storms and surges 



» 




^K^ 



Figure 5.4 Zonation in Sella River near Ambaria Island 

1 Water 4 N\)pa f rut icons 

2 Almost barren mud 5 a) Sonneratia apetala b) Excoecaria agallocha c) Ceriops decandra 

3 Porteresia coarctata 6 Heritiera fames 



50 



World Mangrove Atlas 




Figure 5.5 

SPOT scene KJ 236/306 over 
the Sundarbans 



Figure 5.6 

False colour composite of SPOT 
channels XS3, XS2 and XSl 




South and Southeast Asia 



51 




Plate 5. 1 Mangrove zonation in Bengal 




52 



World Mangrove Atlas 



China and Taiwan 



Maps 5.3 and 5.4 



Land area 

Population (1995) 

GNP(1992) 

Mean monthly temperature range (Taipei, Taiwan) 

Mean annual rainfall 

Area of mangrove on the map 

Number of protected areas with mangrove 



9,596,960 sq km 

1,238,319,000 

380 U5$ per capita 

15-29°C 

2,500 mm 

366 sq km# 

22 



Mangroves are widespread along the coasts of China and Taiwan, but in ahnost all cases they are restricted to 
small stands of relatively stunted and degraded trees. Estimates of mangrove area vary from 200 sq km to 
670 sq km. They are most heavily concentrated on the southernmost coasts, in Hainan Island and Taiwan. In 
Taiwan most remaining mangrove areas are concentrated on the west coast, notably in the Tanshui estuary and 
further south where a number of sites have some legal protection in the Chan-Yun-Chia reserve. Most of the 
coast of Hainan was once fringed with mangroves, but these have largely been destroyed. However, a few small 
areas remain, including ones with well developed mangroves, some of which fall within nature reserves. 
Mangroves have been used extensively for firewood and charcoal production. This is one of the major reasons 
why the area of mangroves has decreased and why remaining mangroves are often shrubby. As the mangrove 
area has decreased, so uses for timber and tannins have declined. Uses in traditional medicine remain important. 
Since the 1960s large areas have been destroyed as land has been reclaimed for agriculture. This has largely 
ceased, but areas are stiU being destroyed for the development of shrimp ponds. By contrast, mangroves, as strip 
forests, are increasingly being promoted for coastal protection. These strips are typically Kandelia candel and they 
are planted in front of reclaimed land. These have been shown to be very effective in reducing the breaching 
and erosion of dykes during cyclones. 

Map reference 

Mangrove coverage gathered from sketch maps drawn onto 1 :500, 000-1 : 1 ,000,000 base maps, prepared for this work by 
Professor Lin Peng, Xiamen University (mainland China) and Dr Jane Lewis, National Taiwan Ocean University 
(Taiwan) . 



Hong Kong 



Map 5.3 



Land area 

Population (1995) 

GNP(1995) 

Mean monthly temperature range 

Mean annual rainfall 

Spring tidal amplitude 

Area of mangrove on the map 

Number of protected areas with mangrove 



1 ,040 sq km 

5,932,000 

1 5,370 US$ per capita 

16-29°C 

2,214 mm 

2.8 m 

2,82 sq km# 

6 



Hong Kong, a small dependent territory of the United Kingdom until July 1 997, and subsequently a part of 
China, has a high population density, mostly concentrated around the coasts. Almost all of the coastal areas have 
been drained and reclaimed for agriculture, fishponds, salt pans and urban development. Tiny areas of mangrove 
are found in scattered sites around the coast, but the only area of significant size is the Mai Po Marsh, in the 
northwest, on the shores of Deep Bay The mangroves in the site are all dwarf. Mai Po is highly managed, most 
of its area consists of shrimp ponds, or Gei wais, and fish ponds. The former often include patches of mangrove, 
while the latter are devoid of vegetation. The site is managed as a nature reserve, and attracts a large number of 
visitors, with a visitor centre, boardwalks and about ten full-time staff. 

Map references 

Coastline and mangrove data from a digital data set provided by WWF HK (1994), prepared at 1:20,000 from 1989 aerial 
photographs taken at the same scale. Details of the data set are provided in Ashworth ct al. (1983). 

Ashworth.J.M., Corlet, R.T., Dudgeon, D, MelviUe, D.S. and Tang, WS.M. (1983). Hom? Kong Flora and Fauna: Computing 
Conservation: Hong Kong Ecological Database. World Wide Fund for Nature Hong Kong. 24 "pp. 

WWF HK (1994). Hong Kong Vegetation Map. 1:20,000 CIS on ARC/INFO prepared by World Wide Fund for Nanire 
Hong Kong. 



India 



South and Southeast Asia 53 



Map 5.1 



Land area 3,287,590 sq km 

Total forest extent ( 1 990) 5 1 7,200 sq km 

Population (1995) 931,044,000 

C5NP(1992) 310 US$ per capita 

Mean monthly temperature range (Calcutta) 19-29°C 

Mean monthly temperature range (Madras) 24-31°C 

Mean monthly temperature range (Bombay) 24-27°C 

Mean annual rainfall (Calcutta) 1,600 mm 

Mean annual rainfall (Madras) 1,270 mm 

Mean annual rainfall (Bombay) 1,800 mm 

Mean annual rainfall (Andaman-Nicobar Islands) 3,200 mm 

Spring tidal amplitude (Calcutta) 5 m 

Spnng tidal amplitude (Bombay) 3.7 m 

Spnng tidal amplitude (Andaman-Nicobar Islands) 1 .9 m 

Alternative estimate of mangrove area (WWF-lndia, pers. comm.) 6,700 sq km# 

Area of mangrove on the map 5,379 sq km 

Number of protected areas with mangrove 21 

India has a coastline of some 12,700 km, which can be divided into west and east coasts, with patchy mangrove 
distribution. There are two chains of ofishore islands, the Lakshadweep Islands in the west and the Andaman and 
Nicobar Islands in the east. About 80% of India's mangroves are found in the east where the coastal profile is 
typically less steeply shelving and rivers and estuaries are better developed. The largest areas are those of the Indian 
part of the Sundarbans, and the Andaman and Nicobar Islands. The Indian Sundarbans are sUghdy more saline 
than the Bangladeshi Sundarbans, with poorer forest development. The Andaman and Nicobar Islands have close 
affinities to the nearby Southeast Asian mangroves and are the only areas with undisturbed mangrovecommunities. 
Elsewhere in India the mangroves have been exploited for thousands of years. Other mangrove areas on the 
eastern coast are associated with the estuaries of the Mahanadi, Godavari, Krishna, and Cauvery Rivers. On the 
west coast there are fringing mangroves along the estuaries of the many small rivers, while there are important 
scrubby communities associated with the and coast around the Gulf of Kutch. In India, fifiy-nine species and 
associated species of mangrove are hsted by Untawale (1986). Some 25 species are found only along the east coast, 
while eight species are restricted to the west coast. The chmate varies around the coasthne. In the Andaman and 
Nicobar Islands and on the southwest coast of Kerala, rainfall of 3,000 mm per year can occur, while the southeast 
coast of the Gulf of Mannar can receive less than 900 mm per year and the Gulf of Kutch only 400-600 mm 
per year. In most areas, rainfall shows a distinct seasonal pattern. 

Most estuarine mangrove areas have human communities close by, while the Sundarbans mangroves have a 
resident population of some two miUion people. Local uses include fijelwood, fisheries, honey production and 
the use oi Nypa leaves for roofing materials. Some 10,000 people live by selling mangrove firewood, the only 
source of firewood in the region in the Gulf of Kutch, and the mangroves are also heavily exploited for grazing 
by camels and cattle. Salt collection is also an important activity in the supralittoral zone, especially in the Kutch 
region. Traditional aquaculture has a long history, with pond construction for fish and shrimp cultivation. This 
has recently been boosted by the development of hatchery technology. In some areas polyculture techniques 
rotate paddy cultivation with prawn farming. Large areas of land have been reclaimed for agricultural purposes and 
urban development. This is increasing with population pressure in all areas. For example, Bombay is built on an area 
that, in 1670, was a group of seven islands surrounded by mangroves. Linked to these issues, pollution firom urban 
and agricultural runofi^is an increasing threat. On the east coast, a number of mangrove areas are managed for timber 
with detailed Forest Working Plans and felling cycles varying fir)m 20 to 100 years. Over-exploitation threatens 
many areas, including the Gulf of Kutch and the Sundarbans. A National Mangrove Committee was established in 
1979, now superseded by a National Committee on Wetlands, Mangroves and Coral Reefs, as an advisory body to 
the government. This body has identified 15 key mangrove areas, including all of the large sites mentioned above, 
and has drawn up Management Action Plans for all of them, to be administered by the state governments with 
financial assistance fixsm the Ministry of Environment and Forests. Small afibrestation schemes have been undertaken, 
notably in the Gulf of Kutch. A number of sites have also been given legal protection, including part of the Gulf of 
Kutch, the Great Andaman Biosphere Reserve and three sites in the Sundarbans. 

Map references 

Some data were obtained from FSI (1986). Further information on the mangrove forest of the Sundarbans was taken from 
Department of Forests (1973). Gaps in these data holdings were filled using Blasco and BeUan (1995), prepared from 
Landsat MSS, Landsat TM and SPOT data. Further approximate areas were added from edits provided by Fran^:ois Blasco. 

FSI (1986). Naftona/ Forest Vegetation Map. 1:1,000,000. Forest Survey of India. 



54 World Mangrove Atlas 

Department of Forests (1973). Forest Map of South India. Department of Forests, Government of West Bengal. 

Blasco, F and Bellan.M.F (1995).^ M-ijc/rtdon Map o/'7ropii:(i/Con(i«('«r(i//lsi(i. 1:5,000,000. Institutde la Carte Internationale 
de la Vegetation, Toulouse, France. 

Indonesia Maps 5.6, 5.7 and s.s 

Land area 1,904,570 sq km 

Total forest extent ( 1 990) 1 ,095,490 sq km 

Population (1995) 201,477,000 

GNP(1992) 2,080 U5$ per capita 

Mean annual temperature (Jakarta) 26°C 

Mean annual rainfall (Jakarta) 1,775 mm 

Spnng tidal amplitude (South Sumatra) 3 m 

Spring tidal amplitude (Java, north coast) 1 m 

Spring tidal amplitude (East Kalimantan) 2 m 

Spnng tidal amplitude (Irian Jaya, north coast) 2 m 

Spnng tidal amplitude (Irian Jaya, south coast) 9 m 

Alternative estimate of mangrove area (Soemodihard|o etal., 1993) 42,550 sq km# 

Area of mangrove on the map 45,421 sq km 

Number of protected areas with mangrove 54 

Indonesia is a vast archipelago consisting of some 17,000 islands. It has the largest area of mangroves of any 
country. Over half of these are concentrated in Irian Jaya, which has some of the largest single stands of mangrove 
in the world. Mangroves are found throughout the country, although they are scarce in west Sumatra. Other 
very large areas are found along the east coast of Kalimantan and the east coast of Sumatra. The diversity of 
mangrove species found in Indonesia is very high. Five major mangrove types or 'consociations' are recognised, 
based on dominant species o{ Aincennia, Rhizophora, Sonneratia, Bruguiera and Nypa. The relative occurrence of 
each of these can be related to ecological factors such as tidal regime, soils and salinity. While more mixed 
associations also occur in some areas, closer inspection of these often reveals a zonation or succession of some 
of the consociations already mentioned. Typically mangroves show a high degree of structural development, 
with trees reaching 50 m in height m many areas such as on the south and east coasts ofSumatra and Kalimantan. 
It IS very difficult to make generalisations about the chmate or physical conditions in a country of this size, but 
most coastal regions have humid tropical or equatorial cUmates, with high humidity, seasonal wind and 
precipitation, a high annual rainfall and high temperatures. Where conditions of rainfall or coastal topography 
are less favourable, mangroves may only form shrubby communities or be virtually absent, such as in the East 
Nusa Tenggara (Lesser Sunda Islands) and western Sumatra. Tidal fluctuations vary enormously over relatively 
short distances due, in part, to the complexity of the coastal configuration. The mangroves of the island of 
Borneo are home to the proboscis monkey Nasalis larmtus, which is one of the few large mammals restricted 
to mangrove environments. 

Losses of mangrove areas in Indonesia can mostly be attributed to the development of shrimp ponds and 
logging activities. Conversion to shrimp ponds is especially prevalent in East Java, Sulawesi and Sumatra. Local 
use of mangrove products includes timber for construction, considerable usage for fuelwood, the use oiNypa 
for sugar production and Nypa leaves for roofing. Commercial uses include charcoal production and large areas 
of logging concessions. Production of woodchips and pulp is increasing. Chip mills have been built in Sumatra 
and Kalimantan, while a major mill has been built to process mangroves from a 1,370 sq km lease in Bintuni 
Bay, Irian Jaya, formerly one of the largest and most pristine mangrove areas in the world. Mangrove associated 
fisheries are important, including finfish, bivalves and crabs. Brackish water fishponds have been used in Indonesia 
since the fifteenth century and in the 1970s they began to be used for shrimp farming. Extensive methods are 
used, relying on natural stocking as well as intensive methods, the fry being obtained from hatcheries, with 
feeding and predator controls applied. Smaller areas of mangroves have been lost or threatened by conversion 
to agriculture, salt pans (Java and Sulawesi), oil extraction (East KaHmantan) and pollution. Recognising the 
importance of mangroves for fisheries, forestry, coastal protection and wildlife, a number of protected areas and 
mangrove greenbelts have been designated. There are also detailed guidelines for sustainable forestry including 
recoinmendations for cutting rotations and leaving uncut strips along the sea front and river channels. There 
have been small reafforestation schemes in some areas. 

Estimates for the total area of mangroves vary considerably. Probably the most widely used is that given by 
Soemodihardjo et al. (1993) of 42,550 sq km, but some estimates are as low as 38,000 or 21,763 sq km. 



South and Southeast Asia 55 



Case study 



The Cauvery Delta (Pichavaram): 
coastal lagoon mangroves 

The coasted lagoon mangroves of the Cauvery Delta (Pichavaram) are a small area of mangroves 
(about 14 sq km), confined to a lagoon in the north of the Cauvery Delta, about 250 km south of 
Madras. They are some of the last remnants of the mangrove ecosystems of Tamil Nadu State 
(India). They provide a very interesting site for the neighbouring Porto Novo Marine Research 
Station which is involved in research on the relationships between mangrove plants and animals. 

The coast in this region is dry, the annual rainfall ranges between 1,200 and 1,500 mm, but 
nearly 80% of this falls during three months (October to December), and these figures fluctuate 
considerably from year to year, relating to the location and extent of typhoons. The dry season 
extends over six to eight months from January to August. The mouth of the Cauvery Delta is 
crossed by a large sand bar, forming an almost closed lagoon. The chances of strong tides or long 
lasting inundation of this lagoon are greatest from October to December. Conversely, from February 
to September, some areas are not flooded at all and it is here that the ecological conditions become 
extreme (high salt concentrations), resulting in an ecosystem of scattered plant communities, 
comprising bushes of Suaeda mahtima and a few other saltmarsh species. 

The mangrove area includes a narrow, almost permanently flooded belt of Rhizophora apiculata 
(less than 10 m height) with a few good specimens of Avicennia officinalis, but the commonest 
tree in Pichavaram is Avicennia marina which tolerates considerable variations of the water salinity 
(to over 70 %o) as well as a long submergence of its pneumatophores during exceptional floods. 
Figure 5.8 illustrates the plant zonation in these mangroves. 

In this highly populated area, about 500 people per sq km, the mangroves are still an important 
source of fuelwood, an essential grazing land and a productive fishing ground. Since 1880, they 
have been declared 'Reserved Forests'. All efforts to protect them and to replant mangrove trees 
have failed, however, and these systems are threatened by both natural environmental and human 
influences. 



Environmental data 

• Mean annual rainfall 1,200 to 1,500 mm/year 

• Dry season 6-8 consecutive dry months (January to August) 

• Cyclonic storms Low frequency (<l/year), but risks of long-lasting floods 

• Mean water salinity 25 to 33%o 

• Dominant soil type Sandy-clayey 

• Average tidal amplitude 0.5 m 

• Average population density >100 people per sq km 

• Total areal extent About 14 sq km 

■ Dominant mangrove types Most extensive mangrove type is a back mangrove shrub with 

Avicennia. There are also well defined Rhizophora belts 



56 



World Mangrove Atlas 




© I.C.I.V. (Toulouse - FRANCE) 1994 



Realization : J.L. CARAYON 



Figure 5.7 Mangroves of Pichavaram 



, V ?.T-v^P»«??VSf-*!ftr«i»WT'W5 



South and Southeast Asia 



57 




Plate 5.3 The mangroves of Pichavaram. One of the last remnants of the mangroves of Tamil 

Nadu State (India). Commonest trees are scattered Avicennia marina 




Figure 5.8 



Zonation in Pichavaram estuary 

1 Rbizophora apiculata BL. 

2 Dalbergia spinosa Roxb. 

3 Ceriops decandra (Griff.) Ding Hou 

4 Sueda maritima (L.) Dum. 



5 Excoecaria agallocha L. 
6a Auicennia officinalis L. 
6b Avicennia marina Vierh. 



58 World Mangrove Atlas 

Map references (Indonesia) 

Data are based on the Regional Physical Planning Programme for Transmigration (RePPProT) work begun in 1984 in 
association with the National Centre for Coordination of Surveys and Mapping (BAKOSURTANAL). Surveys were 
based on existing reports, air photographs and sateUite or radar imagery with selective field checking. Data were generously 
provided to WCMC by the RePPProT team in the form of hand-coloured draft maps at 1:2.5 million scale; Sumatra 
(1988), Java and Lesser Sundas (1989), Lesser Sundas (1989), Kahmantan (Central, 1985; South, West and East, 1987), 
Sulawesi (1988), Moluccas (1989), Irian Jaya (1986). These maps have been further updated from a series of maps provided 
by Willi Giesen of the Asian Wedands Bureau showing key mangrove areas, notably on Sumatra and Irian Jaya. Most 
maps are from unpublished reports (see hst below). The information was transferred to eight A2 maps before digitising. 
Where these data differed fi-om the data described above they were assumed to be more accurate and the latter were 
removed fi-om the present coverage. Areas marked as 'disappeared or very disturbed' were not included. A small number 
of additional edits were provided by Dr Jim Davie, University of Queensland, Australia, and by Fran^iois Blasco. 

AWB (1992). Proposal: Buffer Zones Development of the Berbak National Park. Final Draft. Asian Wedand Bureau, October, 

1992. 
Erftemeijer, P., Allen, G.R. and Zuwendra (1989). Preliminary resource imientory ofBintuni Bay, Irian Jaya, and recommendations 

for conservation and mana^^ement. AWB-PHPA, Bogor, November 1989. 
Giesen, W (1991). Hutan Bakau Pantai Timor Nature Reserve, Jambi Survey Report. PHPA/AWB Sumatra Wedand Project 

Report No. 17. December 1991. 

Giesen, W. (1991). Bakunji Island, Riau (Pulau Bakung, Pulau Basu) Survey Report. PHPA/AWB Sumatra Wedand Project 

Report No. 1 1 . December 1991 . 
Giesen, W.,Baltzer,M. and Baruadi.R. {199 \). Integrating Conservation with Land-use Development in Wetlands of South Sulawesi. 

PHPA/AWB, Bogor, October 1991. 
PETA (1992). Profil Lingkungan Hidup Daerah Lahan Basah Propinsi Jambi Sumatera, Indonesia. PHPA/AWB Proyek Lahan 

Basah Sumatera, Laporan No. 20b. February 1992. 
Silvius, M J. and Taufik, AT (1990). Conservation and land use of Pulau Kimaam, Irian Jaya. PHPA - AWB/INTERWADER, 

January 1990. Unpublished Report. 
Zieren, M.,Yus Rusila Noor, Baltzer,M.and Najamuddin Saleh (1990). Wetlands ofSumba, East Nusa Tengarra.an assessment 

of the importance to man, wildlife and conservation. PHPA/AWB-lndonesia, Bogor, August 1990. 

Japan Map 5.4 

Land area 377,800 sq km 

Total forest extent (1990) 241 ,580 sq km 

Population ( 1 995) 1 25,879,000 

GNP(1992) 28,220 US$ per capita 

Mean annual temperature (Naha, Okinawa) 22°C 

Mean annual rainfall (Naha, Okinawa) 2,037 mm 

Spnng tidal amplitude (Naha, Okinawa) 2 m 

Alternative estimate of mangrove area (Baba, pers. comm.) 4 to 5 sq km# 

Area of mangrove on the map 75 sq km 

Number of protected areas with mangrove 6 

Mangroves are found in the southern part of Japan, scattered throughout the Ryukyu Archipelago and reaching 
as far north as Kiire on southern Kyushu. These are the northernmost mangroves in Asia, at latitude 3r22'N, 
and consist of small stands of Kandelia candel. The total area is small and is largely concentrated on the islands 
of Ishigaki and Iriomote in the Okinawa prefecture. Iriomote has the largest and most diverse communities 
and eleven species of mangrove have been recorded. A few strong typhoons pass over the Ryukyu Islands every 
year and these can damage the trees, typically restricting canopy height to 10-15 in. In some areas they are 
shrubby, but the canopy can be very dense. Some traditional use of mangroves for tannins was recorded from 
Iriomote until just after 1945. More recendy many areas have been destroyed for urban development and road 
construction, although Okinawa prefectural and local governments, together with non-governmental organi- 
sations have started activities to conserve and restore mangrove ecosystems. A traditional proverb is often cited: 
"no forest on the land, no fish in the sea". 

Map references 

Mangroves of Iriomote Island digitised from 1 :50,000 map appended to Aramoto (1986) (map tide; Map of Land Utihsation 
of Iriomote Island) . Mangroves for the remainder of the islands around Okinawa were digitised from Environment Agency 
(1981-1987), while locations of mangrove areas not covered on these maps were gathered from approximate distribution 
maps provided by Dr Shigeyuki Baba (June 1995). 

Aramoto, M. {\986) . Iriomote-jima wo chusin to shita shigen shokubutsu huzongenkyo (Bio-resources distribution in Iriomote Island, 

Okinawa). Pubhshed by Chiiki-sanjyo-gijutsu-shinko-kai, Okinawa Japan. 97 pp. 
Environment Agency (1 98 \-\9?,l). Actual Vegetation Map Okinawa, 1-29. \ ;50,000. The 3rd National Survey on die Natural 

Environment (Vegetation) . Environment Agency, Japan. (29-map series on 26 sheets). 



South and Southeast Asia 59 

Malaysia Maps S.e and 5.7 

Land area 329,750 sq km 

Total forest extent ( 1 990) 1 75,830 sq km 

Population (1995) 20,125,000 

GNP (1 992) 2,800 US$ per capita 

Mean annual temperature (Penang) 28°C 

Mean annual temperature (Sabah) 27°C 

Mean annual rainfall (Penang) 2,736 mm 

Mean annual rainfall (Sabah) 3,700 mm 

Alternative estimate of mangrove area (Chan ef a/ , 1 993) 6,41 2 sq km 

Area of mangrove on the map 6,424 sq km# 

Number of protected areas with mangrove 1 2 

Mangroves are found on all coasts, with the largest area (57%) on the coast of Sabah, concentrated particularly 
in the northeast. Sarawak also has considerable areas (26%), mosdy concentrated in the deltas of the Sarawak, 
Rajang and Trusan-Lawas rivers. Despite having the longest coasdine, Peninsular Malaysia has only 17% of the 
country's mangroves, most of which are concentrated on the more sheltered west coast. In all areas the chmate 
IS hot and humid with high rainfall. There is a very high diversity of species, which in some areas show a relatively 
clear zonation pattern. Typically, there is an Avicennia-Sonneratia community on the seaward sediments, where 
there is soft, deep mud, though Rhizophom-Bru'^uiera forest is often the most dominant. More inland, where the 
soils are firmer, a much wider array of species are typically found. In some areas, Nypa palms form the dominant 
species, particularly where there is a greater freshwater influence. Rates of accretion can be very high, with some 
areas in southern Peninsular Malaysia gaining 40 m per year. Coastal erosion rates can also be high, however, 
and it has been suggested that these have been exacerbated by the removal of mangroves from many areas. 

Mangrove losses have been considerable in many parts of Malaysia: the area of forest reserves decreased by 
12% between 1980 and 1990, mostly through loss of forest area to agriculture, urban development, shrimp 
ponds and deforestation. The use of mangrove areas in Malaysia has a long history. Traditionally, they have been 
harvested for fuelwood, charcoal, timber and poles. The Matang forest on the west coast of Peninsular Malaysia 
has been sustainably managed since the start of this century and is one of the very few examples of successful 
sustained management of a tropical forest ecosystem in the world. In addition to a timber industry employing 
some 2,400 people, with a revenue of US$ 6 miUion per year, there is an associated fishing industry in the area 
which employs about 10,000 people with an annual revenue ofUSS 12-30 million. This contrasts strongly with 
the former Japanese woodchip industries established on Sabah and Sarawak, now closed, which caused 
long-term degradation of wide areas. These had an estimated yield of only 2.5%. of the Matang yield per hectare, 
based on economic considerations and provision of employment. As in other countries, offshore fisheries are 
very important and have been closely linked to the mangroves for a number of fish and prawn species. 
Aquacultural practices include cockle culture, the widespread use of floating cages for fish, and the destructive 
development of ponds, mostly for prawn culture. Although recent, this latter activity has spread very quickly, 
particularly in Peninsular Malaysia, leading to the clearance of large areas. The National Mangrove Committee 
of Malaysia has strongly suggested that strict guidelines should be established for the development of this industry 
in the fiiture. Clearance for agriculture has occurred, but in some cases has been very unsuccessful due to the 
acidification of the soils. Considerable areas are now being reclaimed, again particularly in Peninsular Malaysia, 
for urban development and the development of tourist resorts. In some areas the replanting of mangroves is taking 
place and this is a routine activity in the Matang mangrove forest. All mangroves come under the jurisdiction of 
the respective State Forest Departments. Only a very small percentage of Malaysian mangroves fall within legally 
gazetted protected areas: 0.3% in Peninsular Malaysia; 0.2%. in Sarawak; and 1.3% in Sabah. 

Map references 

Data for Sabah are taken from Sabah Forestry Department (1989). This provides a useful representation of forests within 
the protected and gazetted forests in the Permanent Forest Estate, but gives no indication of the extent (if any) of additional 
natural stateland forests. For Sarawak the key source was Lands and Surveys (1979). The data for Peninsular Malaysia are 
taken from Forest Department (n.d.). Although undated, this unpublished map is an updated version of a map pubhshed 
in 1986. 
Sabah Forestry Department (1 989) . Sahah Malaysia, Natural and Plantation Forests. 1 : 1 ,270,000. Sabah Forestry Department, 

Malaysia. 
Lands and Surveys (1979). Sarawak: Forest Distribution and Land Use Map. 1:1,000,000. Director of Lands and Surveys, 

Sarawak, Malaysia. 
Forest Department (n.d.). Peninsular Malaysia: The Forfs(/4rM. 1:1,000,000. Hand-coloured map obtained from the Forest 

Department, Kuala Lumpur in May 1989. 



60 World Mangrove Adas 

Myanmar Map 5.2 

Land area 676,550 sq km 

Total forest extent (1990) 2 88, 560 sq km 

Population (1995) 46,548,000 

Mean annual temperature 27°C 

Mean annual rainfall 2,516 mm 

Alternative estimate of mangrove area (Htay, 1994) 3,786 sq km# 

Area of mangrove on the map 3,444 sq km 

Number of protected areas with mangrove 

There is little published information on the mangroves in Myanmar. The largest areas are in the Irrawaddy 
Delta, but these are reported as being heavily degraded and in 1983 it was reported that there were only 
235 sq km of undisturbed mangrove in the country. These pristine areas are mostly concentrated away from 
the Irrawaddy in the two other major areas of mangrove in the country: the northern state of Arakan, and in 
the south near the border with Thailand in Tenasserim. Mangroves are also found on the offshore islands. In 
the Irrawaddy Delta, mangroves have largely gone from the eastern areas. There are several forest reserves in 
the western areas, and scrubby mangrove forest remains in these, although it is heavily utilised as a source of 
fuelwood and charcoal for Rangoon. Mangrove plantations have been established in Taikkyi near Rangoon. 

Map references 

Data for the Irrawaddy Delta were obtained from Blasco and Bellan (1995), prepared from Landsat MSS, Landsat TM 
and SPOT data. Further data were added based on the mangrove arcs shown on Petroconsukants SA (1990). 

Blasco, F and Bellan, M.F (1995).^ Vcgetalion Mnp of Tropical Conlincntal Asia. 1:5,000,000. Institut de la Carte Internationale 
de la Vegetation, Toulouse, France. 

Petroconsukants SA (1990). MUNDOCART/CD. Version 2.0. 1:1,000,000 world map prepared from the Operational 
Navigational Charts of the United States Defense Mapping Agency Petroconsukants (CES) Ltd, London, UK. 

Pakistan Map 5.1 

Land area 796,100 sq km 

Total forest extent (1990) 18,550 sq km 

Population (1995) 134,974,000 

GNP(1992) 410 US$ per capita 

Mean monthly temperature range 18-31°C 

Mean annual rainfall 220 mm 

Alternative estimate of mangrove area (Qureshi, pers comm.) 1 ,600 sq km 

Area of mangrove on the map 1 ,683 sq km# 

Number of protected areas vi/ith mangrove 2 

The coastHne of Pakistan is essentially arid, with low rainfall, mostly falling during the monsoon period (April 
to September). This has an important effect on the distribution and development of mangroves, with the largest 
area being found in the Indus Delta, and the remainder being mostly restricted to small patches in bays and 
river mouths. The mangroves of the Indus Delta are ahnost completely monospecific Aincennia marina, which 
is highly resistant to the relatively extreme conditions of temperature and sahnity. 

Mangroves m the Indus Delta have been heavily used by man for fuelwood, fodder and grazing, particularly 
camels. There is some collection of timber for supply to markets in Karachi. Artisans and commercial fisherfolk 
use the mangrove areas for prawn and fish capture and, during the fishing season (October to May), move into 
the mangroves and establish temporary villages in some of the creeks. Fisherfolk also use the mangroves for 
poles and fuelwood. Such activities are a threat to mangroves, only if there is overuse - this has occurred in a 
number of areas, leading to extensive loss and degradation. Considerable threats also arise from pollution and 
increasing saUnities, the former particularly from industrial effluents from Karachi, and the latter from 
interruptions to the flow of the Indus with the construction of barrages and diversion of water for irrigation. 
Increasing salinities are likely to further stunt tree growth, and may be the cause of reduced seedhng recruitment 
observed in some areas. The reduced flow of the Indus is also reducing the input of silt into the system, which 
could have further long-term effects. Oil pollution discharged from the many ships visiting Karachi is a large 
and increasing threat. A number of mangrove species have been disproportionately affected by anthropogenic 
impacts, even to the point of probable extermination. This may be attributable to increasing sahnities in the 
Delta, over-exploitation, or both. Two large areas within the Indus Delta were declared as protected forest in 
1957 and are managed by the Forest Department, while there are increasing efforts to estabhsh mangrove 
plantations. Some 50 sq km have now been planted in the Indus Delta. 



South and Southeast Asia 61 

Map reference 

Mangroves for the Indus Delta were extracted from 1:1,000,000 map in Meynell and Qureshi (1993). Remaining areas 
were added to a 1:1,000,000 base map by S.M. SaifuUah, Karachi Umversity. 

MeyneU, P.J. and Qureshi, M.T. (1993). Sustainable management of the mangrove ecosystem in the Indus Delta. In: Wetlands 
and Waterfowl Consermtian in South and West Asia. Moser, M. and van Wessen, J. (Eds). IRWB Publications, No. 25, 
Gloucester, UK. 

The Philippines Map 5.5 

Land area 300,000 sq km 

Total forest extent (1990) 78,310 sq km 

Population (1995) 69,257,000 

GNP (1 992) 770 U5$ per capita 

Mean monthly temperature range (Manila) 25-28''C 

Mean annual rainfall (Manila) 2,083 mm 

Spring tidal amplitude (Luzon) 1 .68 m 

Spring tidal amplitude (Panay) 2.16 m 

Alternative estimate of mangrove area (Ajiki, 1994) 1 ,325 sq km 

Area of mangrove on tfie map 1 ,607 sq km# 

Number of protected areas witfi mangrove 7 

The Philippines is a large archipelago of approximately 7,000 islands. Mangroves in the Philippines were once 
estimated to cover 4,000 sq km, but have decreased to one third or one quarter of their original extent. The 
largest remaining areas are located to the south of the archipelago, on Mindanao and Samar, and also on Palawan 
in the west. The diversity of mangrove species is high, and quite clear, though complex zonation patterns have 
been described for undisturbed communities. The country has a tropical monsoon climate, with high humidity 
and rainfall. It is also strongly affected by tropical cyclones which can have a devastating effect on human 
populations on the coast. 

Offshore fisheries are of considerable importance in the Philippines. There have been few studies to look at 
the effect of mangrove loss on these, although anecdotal evidence suggests there have been reducedyields. There 
is little or no commercial extraction of timber, but mangrove wood is widely used locally for fuel, charcoal and 
for the manufacture of poles and piles. There has been some mangrove afforestation, notably in the Sulu 
Archipelago and the central Visayas, including Negros, Bohol and Cebu, much of this carried out at the local 
and community level. Research into afforestation methods is also underway. Traditional or non-destructive 
fishing within mangrove areas is stiU important, notably in Bohol, Sulu and Cebu. Target species include shellfish 
and crabs as well as fish caught by net or line. The greatest loss of mangrove areas has been caused by the 
development of large areas of brackish fishponds, increased from 900 sq km in 1952 to over 2,100 sq km today. 
This conversion has been strongly encouraged by the government policy of leasing out mangrove areas to 
increase fish production. Mangrove reclamation for agricultural or urban development is significant in some 
areas. 

Although some legislation exists for the protection of mangroves, for exainple all of the mangroves of Palawan 
and other sites have been declared a mangrove forest reserve, there is little evidence that such protection is 
effective on the ground. 

Map reference 

Processed sateUite imagery has been kindly provided by NAMRIA (1988), prepared from SPOT images taken in 1987, 
at a scale of 1:250,000. Some of the smallest islands in the southwest, central and northern parts of the country are not 
included in the coverage, but are not likely to make a significant difference to the total area. 

NAMRIA (1988). Land Cover Maps. 1 :250,000. National Mapping and Resources Information Authority, Manila, Republic 
of the Philippines. 



62 World Mangrove Atlas 

Singapore Maps.e 

Land area 620 sq km 

Total forest extent ( 1 990) 40 sq km 

Population (1995) 2,853,000 

GNP(1992) 1 5,790 US$ per capita 

Mean monthly temperature range 26-27''C 

Mean annual rainfall 2,358 mm 

Spring tidal amplitude 3.5 m 

Alternative estimate of mangrove area (Chou, 1990) 6 sq km# 

Area of mangrove on the map No data 

Number of protected areas with mangrove 2 

Singapore is a small, densely populated island at the southern tip of the Malaysian peninsula. Originally 
mangroves covered 13% of the island, or sorne 75 sq km, but they have now been almost totally destroyed. 
Original uses included fuelwood and charcoal and over-exploitation led to wide-scale degradation by the 
mid-nineteenth century. The first land reclamation activities were begun on the Singapore River in 1822. By 
the middle of this century large areas had been reclaimed and this continues today. Shrimp farming was 
introduced in the 1900s and led to the loss of wide areas of mangroves as brackish water ponds were developed. 
Today, the total area occupied by shrimp farming is decreasing as the ponds themselves are reclaimed for urban 
expansion. The most recent, and now widespread, threat is the barraging of all the major non-urban estuaries 
as freshwater reservoirs. These estuaries were the last areas where mangroves were found to any extent. All that 
now remains are a few scattered patches of degraded mangrove along the north shore and some of the offshore 
islands. Although a species list is given it is likely that some of the species hsted may now be extinct in Singapore. 

Map reference 

No data 

Sri Lanka Map 5.1 

Land area 55,610 sq km 

Total forest extent ( 1 990) 1 7,460 sq km 

Population (1995) 18,346,000 

GNP(1992) 540 US$ per capita 

Mean monthly temperature range (Colombo) 27-28°C 

Mean monthly temperature range (Tnncomalee) 26-30°C 

Mean annual rainfall (Colombo) 2,424 mm 

Mean annual rainfall (Tnncomalee) 1,580 mm 

Spring tidal amplitude <1 m 

Alternative estimate of mangrove area (Jayewardene, 1 986) (63 sq km)* 

Area of mangrove on the map 89 sq km# 

Number of protected areas with mangrove 8 
* does not include entire country 

Although mangroves are found on all coasts they are restricted in some areas by high exposure. The greatest 
concentrations are along the east and west coasts and around the Jaffna Peninsula in the north, with the largest 
single area probably being that around the Puttalam Lagoon on the west coast. Low tidal ranges throughout 
the country typically preclude the development of wide areas of mangrove although tidal zonation patterns 
have been observed. Five kinds of mangrove system have been described: riverine, fringing, basin, scrub and 
overwash. Each system has a characteristic flora. The best developed system is riverine. Traditionally, mangroves 
have been used for firewood, tannins and poles for construction. Mangrove poles and posts are also used in the 
construction of large fish traps. Large-scale commercial exploitation does not take place although there are 
some mangrove plantations, notably in the Negombo Lagoon, which are managed largely for firewood and 
poles for local markets. Aquaculture is not widespread, but is found in a few ponds around Negombo Lagoon. 
Conversion of land for agriculture has been one of the major causes of mangrove loss, notably for coconut 
plantations, while, more recently, the conversion of mangrove areas for tourist resort development is increasing. 

Map reference 

Data were kindly provided by the ODA Forest Mapping and Planting Project of the Forest Department in Sri Lanka, 
prepared from Landsat TM unagery, incorporated onto a 1:50,000 base map. Most source images were from 1992, with 
analysis and ground-truthing completed by 1994. Details of the dataset provided in Legg and Jewell (n.d.). 
Legg and Jewell (n.d.). A 1:50,000 scale forest map of Sri Lanka: the basis for a national forest GIS. Unpublished report of 
the ODA Forest Mapping and Planting Project, Forest Department, Colombo, Sri Lanka. 



South and Southeast Asia 63 



Case study 



The mangroves of Balochistan, Pakistan 

(Text and data for this section were kindly supplied by Dr M. Tahir Qureshi, lUCN, Karachi, Pakistan) 

The mangroves in the east of Balochistan are very limited in extent, covering a total area of under 
80 sq km. Figures giving the mangrove coverage in the area are provided in Table 5.2. These have 
been derived from satellite imagery by the Space and Upper Atmosphere Research Commission 
(SUPARCO). There is considerable variation in the density of these mangrove stands and much of 
the mangrove area in Kalmot Hor and Gawater Bay is predominantly sparse growth with only a 
few dense stands. 

Out of the eight species recorded from Pakistan, only three are found along the Balochistan coast: 
Avicennia marina, Rhizophora mucronata, and Ceriops tagal. At present, A. marina is the 
dominant species growing in the mangrove forests of Sonmiani. Stands of R. mucronata occur at 
the front of some creeks and Ceriops tagal is found occasionally in localised patches. The total 
cover of these latter two species is small compared with that of A. marina. 

The mangroves in this area are stressed by the naturally harsh conditions of high salinity and 
aridity. Most of the Auicennia and Rhizophora stands are stunted and the rate of soil erosion is 
severe in such areas. There is also pressure from the coastal population on the mangrove 
ecosystems. The local fishermen intensively collect fuelwood and fodder from the forest and this 
has led to the development of large salt pans in various places. 

Figure 5.9 shows the distribution of mangroves in the Indus Delta, where most of Pakistan's 
mangroves are located. Figure 5.10 is a SPOT image showing the mangroves of Sonmiani in more 
detail. 

Environmental data - Sonmiani Bay 

• Mean annual rainfall 180 mm 

• Dry season 8 consecutive dry months (September to April) 

• Riverine input From the Piroli River, which is seasonal, flooding the mangrove area 

during the rainy season 

• Mean water salinity 30 to 50%o 

• Dominant soil types Clayey-loamy, sandy-loamy 

• pH of the topsoil 7 to 8 

• Average tidal amplitude 2-3 m 

• Local population Dam village has a population of 12-15,000 

- these are predominantly fisherfolk, with a few graziers 

• Total areal extent 31 sq km (Sonmiani); 73 sq km (Balochistan coast) 

• Main mangrove species Auicennia marina, Rhizophora mucronata and Ceriops tagal 

Table 5.2 The distribution of mangrove vegetation along the east coast of Balochistan, Pakistan 

Site Area (sq km) Percentage of total 

Miani Hor/Sonmiani 31.0 42 

Dense mangrove 16.6 

Normal mangrove 10.9 

Sparse mangrove 3.5 

Kalmot Hor 21.6 30 

Normal mangrove 2.6 

Sparse mangrove 19.0 

Gawater Bay 20.8 28 

Normal mangrove 0.6 

Sparse mangrove 20.2 

Total 73.4 100 



64 



World Mangrove Atlas 




z WIUW 



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South and Southeast Asia 



65 




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66 World Mangrove Atlas 

Thailand Maps 5.2 and 5.6 

Land area 513,120 sq km 

Total forest extent (1990) 127,350 sq km 

Population (1995) 58,265,000 

GNP(1992) 1,750 US$ per capita 

Mean monthly temperature range (upper Gulf of Thailand) 28-30''C 

Mean monthly temperature range (Andaman 5ea) 25-29°C 

Mean annual rainfall (upper Gulf of Thailand) 1,556 mm 

Mean annual rainfall (Andaman Sea) 4,015 mm 

Spring tidal amplitude (Gulf of Thailand) 1-2 m 

Spring tidal amplitude (Andaman Sea) 3-6 m 

Alternative estimate of mangrove area (IDRC/NRCT/RFD, 1991) 1,964 sq km 

Area of mangrove on the map 2,641 sq km# 

Number of protected areas with mangrove 13 

Thailand has an extensive coast along the Gulf of Thailand and a shorter coast on the Andaman Sea. It is on 
the latter coast that mangroves are most heavily concentrated with 75-80% of the country's mangroves, and it 
is also here that most of the remaining old growth forest is to be found. 

Wide areas of Thailand's mangroves have been selectively cut. About 90% of the wood harvest is for charcoal 
manufacture and about 40%) of this is exported to Malaysia, Singapore and Hong Kong. Offshore capture 
fisheries, fish and shrimps, are important and partly dependent on the mangrove environment. Mollusc culture 
on the mudflats and channels has been practised for many years in soine areas. Shrimp farming has boomed 
since the 1970s, particularly on the Gulf coast and has led to the clearance of large areas. Poor practices have 
led to a limited lifespan of 3-4 years on some farms which have then been abandoned, creating large areas of 
degraded land. The other major cause of mangrove clearance has been coastal development, mosdy urban and 
industrial, but also for agriculture. Salt ponds and tin mining have also led to the loss of some areas. Rates of 
loss can be very high indeed and were reported at 130 sq km per year for the period 1979-1986, with a 50% 
loss of the entire mangrove area between 1975 and 1991. Active erosion processes along the northern Gulf of 
Thailand may have been exacerbated by the mangrove clearance that has taken place in this region. Concern 
about the loss of mangroves has led to a number of legal and policy measures for their protection and sustainable 
use: strict rules are applicable on mangrove concessions to maintain sustainability; there are also three state 
owned seedling production centres. State owned forest plantations cover some 295 sq km, with private 
plantations on a fijrther 28 sq km. Some of the mangroves fall within national parks and other protected areas, 
notably those on the Andaman Sea. 

The considerable discrepancy between the map figure and the quoted alternative estimate of mangrove area 
is of some concern as both figures purport to be derived from the same source. 

Map reference 

Mangrove polygons were prepared from the four-map series (IDRC/NRCT/RFD, 1991) produced as a part of the Remote 
Sensing and Mangroves Project (Thailand) at a scale of 1 :500,000. Sources for these maps were Landsat MSS data recorded 
in 1986-1987. 

IDRC/NRCT/RFD (\99\). Remote Sensinn and Mangroves Project (Tliailand). Series of four maps prepared at 1:500,000 by 
the Remote Sensing Division of the National Research Council. International Development Research Centre, National 
Research Council of Thailand and the Royal Forestry Department. 



South and Southeast Asia 67 



Case study 



Estuarine mangroves in Thailand: Ranong 

In recent years the total area of the mangroves in Thailand has declined considerably, being reduced 
from over 4,744 sq km in 1961 to 2,451 sq km in 1986. In the seven years from 1979 to 1986, 
over 1,500 sq km of mangrove disappeared in Thailand (see Table 5.3). 

Much of the loss of mangroves in Thailand has occurred because the mangrove areas have been 
converted to aquaculture ponds. Several techniques are currently used by aquaculture operators 

I the drainage conditions and hydrological regime. Many mangrove species (flora as well as faunc 
in the impounded areas are destroyed. Table 5.4 shows the evolution of shrimp aquaculture ii 
"Thailand. 
T 

The mangroves of Ranong 

The mangrove communities of the Klong Ngao and Kra Buri estuaries, near Ranong (Figure 5.12 
are located some 600 km southwest of Bangkok, in the Andaman Sea. Their relative isolatior 
^partly explains why they are less disturbed than most Thai mangroves. They have been studied foi 
IiTiany years thanks to the facilities provided by the Mangrove Forest Research Centre. The curreni 
■^account and images provide an overview of the key features of these mangroves as they can be 
'observed either from space, from aerial photographs, from the field or from the laboratory. 

Environmental data 

• Mean annual rainfall >4,000 mm/year 

• Dry season 4 consecutive dry months 

'• Riverine input On the estuaries of the Kra Buri and Klong Ngao Rivers; 

good freshwater supply 

• Water salinity 15 to 30% 
'• pH of the topsoil 7 to 8 

■ Dominant soil type Clayey or loamy clayey 

• Average tidal amplitude 2.5 m 

• Mciximum spring tide 4 m 

• Average population density Unknown. Probably lower than 10 people/sq km. Few villages of 

mangrove dwellers with little human pressure on the ecosystem 

• Total areal extent 1,964 sq km 

• Dominant mangrove type Estuarine with a complex mangrove species distribution. 

Very unclear zonation 

• Main mangrove species Auicennia alba, Bruguiera cvlindrica, B. parviflora, Ceriops tagal, 

Rhizophora apiculata, R. mucronata 

The Ranong mangroves cover 11.5 sq km, on the Andaman coastline, at about 9° 50' North on 
the estuary of the Kra Buri River which forms the border between Thailand and Myanmar. Due to 
the very moist climatic conditions (4,000-5,000 mm of rainfall, 180-200 rainy days per year), it is 
quite difficult to obtain good quality satellite data in the visible and infrared wavelengths. In spite 
of the high frequency of a dense cloudy coverage a reasonably good Landsat TM scene was recorded 
on the 19th of January 1989 (Figure 5.11). The corresponding map is the result of the analysis 
of this image. 

Patterns of zonation are usually indistinct. From one site to another, species distribution varies 
considerably, without any clear natural explanation. This is probably the result of ancient human 
interference, including wood extraction and mining. Other factors, including erosion, accretion. 



66 

Thailan 



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Tot. 
Po 
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^ 



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the 
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IT! 

6 
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World Mangrove Atlas 



tectonic activity and sea level fluctuations, have probably affected the complex mangrove species 
distribution patterns observed. 

The largest trees {Rhizophora apiculata) reach 30 m in height. Although the exact response of 
trees to the various secisonal parameters is not known, the mangroves of Ranong are primarily 
evergreen with some deciduous species, such as Excoecaria agallocha, although this is not 
common at Klong Ngao. The fraction of primary production (leaf litter) exported during every tidal 
cycle to adjacent coasteil waters is probably in the order of 10 to 15%. 

These mangroves have been the subject of a considerable amount of integrated studies (plants, 
animals, soils, waters, etc.); a summary of some of the results of this work is published in 
UNDP-UNESCO (1991). 




Plate 5.4 Most of the mangroves of Thailand are threatened by the development of shrimp-pond 

aquaculture. Along the eastern coast (Gulf of Thailand) only remnants of the original 
ecosystems remain, as seen here in Khlung 



Table 5.3 Changes in the distribution of mangroves in Thailand (from Silapathong, 1992) 



Region 



Area (sq km) 



Rainfall 



Gulf of Thailand 
eastern coast 



1961 



1975 1979 1986 



490 



441 



280 



mean (mm/yr) rainy days 



1,311-4,761 109-192 



Gulf of Thailand 
northern coast 



273 231 



Gulf of Thailand 
western coast 



1,065 447 



419 204 



1,119-2,382 



128-172 



Eastern coast of 
Andaman Sea 



3,679 3,127 2,873 1,964 



2,232-4,198 170-199 



South and Southeast Asia 



69 



From Landsat FM n° 130/53 (16 March 1992) 



Interpretation 





^H Main mangrove aiea 
'^^ Siltation in progress 
^H Hill forests and thickets 



Crops and orchards 

Almost barren soils 
(sands, wet lands etc.) 

c , 5km 
Scale I I 



Figure 5.11 A satellite view of the distribution of the mangroves of the Ranong area 



in'Raai^'.. 



'jssa.'-.^is^T^ 



70 



World Mangrove Atlas 



49 50 '^1 




^^1 Mangrove 
I. I Sand 
I Others 



Figure 5.12 A detailed map of the Ranong mangrove ecosystem. The mangrove 
research centre is located upstream on the Klong Ngao River 
(from UNDP-UNESCO, 1991) 



Table 5.4 Changes in marine shrimp aquaculture in Thailand (1972-1988) 

(Chomdecha and Phoochareon, 1979) 



Year Area Number of 

(sq km) owners 



Production (tonnes/year) 



Penaeus Penaeus Metapenaeus Others Total 

monodon tnerguiensis monoceros 



1972 91 1,154 

1977 124 1,437 20 721 

1982 308 3,943 96 6,346 

1988 667 11,838 40,774 9,226 



599 
2,454 
3,560 



1,450 1,450 

250 1,590 

1,195 10,091 

2,037 55,597 



South and Southeast Asia 71 

Vietnam Map 5.3 

Land area 331,690 sq km 

Total forest extent ( 1 990) 83, 1 20 sq km 

Population (1995) 73,811,000 

Mean monthly temperature range (Hanoi) 1 7-29°C 

Average temperature (south Vietnam) 27°C 

Mean annual rainfall (Hanoi) 1,830 mm 

Mean annual rainfall (Ca Mau peninsula) 2,550 mm 

Spnng tidal amplitude (Ca Mau peninsula) 3 m 

Alternative estimate of mangrove area (Hong and San, 1993) 2,525 sq km# 

Area of mangrove on the map (2,723 sq km) 

Number of protected areas v/\th mangrove 2 

Vietnam has a long coastline facing the South China Sea. It has been estimated that mangroves in this country 
once covered an area of some 4,000 sq km. This area has now been reduced considerably, one of the major 
causes bemg the widespread use of herbicides and napalm during the Vietnam war (1962-1972). About 1,050 
sq km (36%) of the total mangrove area in the south was destroyed during the Vietnam war. Remaining forests 
consist mainly of secondary growth, much of it scrubby, and plantations. The largest areas of mangrove are in 
the Mekong Delta and further south on the Ca Mau peninsula. These were also the areas most heavily degraded 
during the Vietnam war and primary forest is not widespread. There are very few mangroves along the central 
parts of the country where the coasdine is quite exposed and tidal fluctuations are low. In the north, mangroves 
have developed in river deltas and estuaries and on wide tidal flats. There are fewer species here than in the 
south of the country, possibly due to the lower temperatures, but there are some primary forests with mixed 
stands of trees reaching 8 m in height. 

The forests have a wide range of traditional uses: charcoal, fuelwood, honey production, timber and thatching 
materials. In the south many villages consist of houses built on stilts on the river banks and people make a good 
part of their living from fish, shrimp and crab fisheries. Severe erosion has occurred in some areas as a direct 
result of this and vast areas have degraded soils where mangroves have not regenerated, or have formed scrubby 
and commercially worthless formations. Since the 1 980s there have been further considerable losses, particularly 
in the southwest, with the development of shrimp ponds. Conversion of land to salt ponds and to agriculture 
has also been widespread, although the latter, typically, only lasts a few years before the soils become degraded. 
Vietnam has made considerable efforts to restore mangrove areas and there are estimated to be some 466 sq km 
of mangrove plantations in the country. 

Map reference 

Data showing mangrove in the Mekong Delta only are taken from Anon. (1987), believed to be the result of a forest 
inventory in 1987. Further approximate areas were added from edits provided by Fran(;ois Blasco. 

Anon. (1987). Cac Loai Thuc Vat hi dc Doa Dien Hinh va Mot Vung Tap Trung. 1:4,000,000. Publisher unknown. 

Sources 

Ajiki, K. (1994). The decrease of mangrove forests and its effects on local people's lives in the Philippines. In: Proceedings of 
the VII Pacific Inter- Congress Mangrove Session, Mangrove Session. Mangrove Ecosystems Proceedings No 3. International 
Society for Mangrove Ecosystems, Okinawa, Japan, pp. 43-48. 
Aksornkoae, S. (1986). Thailand. In: Mangroves of Asia and the Pacific: Status and Management. Umali, R.M., Zamora, P.M., 

Gotera, R.R., Jara, R.S., Camacho, A.S. and Vannucci, M. (Eds). UNESCO/UNDP, Manila, Philippines, pp. 231-261. 
Aksornkoae, S., Paphavasit, N. and Wattayakorn, G. (1993). Mangroves of Thailand: present status of conservation, use 

and management. In: Ttie Economic and Environmental Values of Mangrove Forests and their Present State of Conservation in 

the South-East Asia/Pacific Region. Clough, B. (Ed). Mangrove Ecosystems Technical Reports. International Society 

for Mangrove Ecosystems, Okinawa, Japan, pp. 83-133. 
Ansari.TA. (1986). Pakistan. In: Mangroves of Asia and the Pacific: Status and Management. UmaU, R.M., Zamora, P.M., 

Gotera, R.R.,Jara, R.S., Camacho, A.S. and Vannucci, M. (Eds). UNESCO/UNDP, Manila, Philippines, pp. 151-173. 
Baba, S. (1994). Mangroves and their utilisation. Bulletin of the Society of Sea Water Science, Japan 48: 367-277. 
Blasco, E (1975). The mangroves of India. Inst. Fr. Pondichery. Trav. Sect. Sc. Techn. T XIV. (Text in French and English). 

175 pp. 
Caratini, C, Blasco, F. and Thanikaimoni, G. (1973). Relation between the pollen spectra and the vegetation of a south 

Indian mangrove. Pollen et Spores 15 (2): 281-292. 
Chan, H.T (1986). Malaysia. In: Mangroves of Asia and the Pacific: Status and Management. Umali, R.M., Zamora, P.M., 

Gotera, R.R.,Jara, R.S., Camacho, A.S. and Vannucci, M. (Eds). UNESCO/UNDP, Manila, Philippines, pp. 131-150. 



12 World Mangrove Atlas 

Chan, H.T., Ong,J.E., Gong, W.K. and Sasekumar, A. (1993). The socio-economic, ecological and environmental values 

of mangrove ecosystems m Malaysia and their present state of conservation. In: The Economic and Environmental Values 

of Mangrove Forests and their Present State of Conservation in the South-East Asia/Pacific Region. Clough, B. (Ed.). 

Mangrove Ecosystems Technical Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 41-81. 
Chaudhury, M.U. (1989). Mangroves in Bangladesh and Remote Sensing appUcations for their analysis. PhD Thesis, 

University Paul Sabatier, Toulouse, France. 150 pp. 
Chomdecha, V. and Phoochareon, V (1979). Coastal aquaculture in Thailand. In; Report of the 3rd National Seminar on 

Mangrove Ecology. Vol. I. April 8-12, Songkhlanakarin. Univ. NRCT, Thailand, pp. 187-226. 
Chou, L.M. (1990). Assessing the coastal living resources of Singapore: a study in the ASEAN-Austraha Coastal Living 

Resources Project. PKi/ZdcraMa. Vol. 59-60. pp. 7-9. 
Choudhury, A.M., Quadir, DA. and Islam, J. M. (1993). Study of Chokoria Mangroves Using Remote Sensing Techniques 

ISME Technical Report - 4. International Society for Mangrove Ecosystems, Okinawa.Japan. 36 pp. 
Clough, B.F. (1993). The Economic and Environmental Values of Mangrove Forests and their Present State of Conservation in the 

South-East Asia/Pacific Region. Mangrove Ecosystems Technical Reports No. 1 . International Society for Mangrove 

Ecosystems, Okinawa, Japan. 202 pp. 
CoUins.N.M., Sayer,J.A. and Whitmore, TC. (1991). The Conservation Atlas of Tropical Forests: Asia and the Pacific. 

MacmiUan Press Ltd, London, UK. 256 pp. 
Corlett, R. (1986). Singapore. In: Mangroves of Asia and the Pacific: Status and Management. Umali, R.M., Zamora, P.M., 

Gotera, R.R., Jara, R.S., Camacho, A.S. and Vannucci, M. (Eds). UNESCO/UNDR Mamla, Phihppines. pp. 21 1-218. 
Curtis, SJ. (1933). Working plan for the forests of the Sundarbans division for the period from 1st April 1931 to 31st 

March 1951. Vol. 1. Parts 1 and II and appendix I. Calcutta, India. 176 pp. 
Davie,J.D.S. (1989). The status of mangrove ecosystems in the Asia Pacific region. Draft report prepared as a 

contribution to Collins ct at. (1991). Tlie Conservation Atlas of Tropical Forests - Asia and the Pacific. 
Hong, P.N. and San, H.T. (1993). Mangroves of Vietnam. lUCN - The World Conservation Union, Bangkok, Thailand. 

173 pp. 
Htay, U.A.S. (1994). Re-afforestation of mangrove forests in Myanmar. In: Proceedings of the Workshop on ITTO Project: 

Development and Dissemination of Re-afforestation Techniques of Mangrove Forests. ]AM and NATMANCOM/NRCT 

(Eds). Japan Association for Mangroves and Thai National Mangrove Committee, Bangkok, Thailand, pp. 169-185. 
ISME (1994). Proceedings of the VII Pacific Inter-Congress Mangrove Session, Mangrove Session, Okinawa, fapan l-2fuly, 1993. 

Mangrove Ecosystems Proceedings No. 3. International Society for Mangrove Ecosystems, Okinawa.Japan. 120 pp. 
lUCN (1983). Global Status of Mangrove Ecosystems. Commission on Ecology Papers No. 3. Saenger, P., Hegerl, EJ. and 

Davie.J.D.S. (Eds). International Umon for Conservation of Nature and Natural Resources, Gland, Switzerland. 

88 pp. 
Jayewardene, R.P (1986). Sri Lanka. In: Mangroves of Asia and the Pacific: Status and Management. Umah, R.M., Zamora, 

PM., Gotera, R.R.,Jara, R.S., Camacho, A.S. and Vamiucci, M. (Eds). UNESCO/UNDR Manila, Phihppines. 

pp. 219-230. 
Kerrest, R. (1980). Contribution a I'etude ecologique de la mangrove de Pichavaram (Inde du Sud). Tamil Nadu. PhD 

Thesis, Paul Sabatier University, Toulouse, France. 93 pp., 1 map. 
Mekong Secretariat (1994). Cambodia Land Cover Atlas 1985/87 - 1992/93 (including national and provincial 

statistics). Remote Sensing and Mapping Unit, Mekong Secretariat; United Nations Development Programme; Food 

and Agriculture Organisation, Cambodia. 124 pp. 
Niiro, Y., Shinjo, K., Kabashima, T. and Miyagi, Y. (1984). Vegetation and ecological distribution of mangrove forests at 

the Shiira River, Iriomote-jima, Okinawa. In: Ecology and Physiology of the Mangrove Ecosystem. Ikehara, S. and Ikehara, 

N. (Eds). College of Science, University of the Ryukyus, Okinawa.Japan. pp. 63-92. 
Peng, L. (1994). The utilization of mangroves m China. In: Proceedings of the VII Pacific Inter-Congress Mangrove Session, 

Mangrove Session. Mangrove Ecosystems Proceedings No. 3. International Society for Mangrove Ecosystems, 

Okinawa, Japan, pp. 11-14. 
Phihppine National Mangrove Committee. (1986). Philippines. In: Mangroves of Asia and the Pacific: Status and 

Management. Umali, R.M., Zamora, P.M., Gotera,R.R.,Jara,R.S., Camacho, A.S. and Vannucci, M. (Eds). 

UNESCO/UNDP, Manila, Phihppines. pp. 175-210. 
Qureshi, M.T. (1996). Restoration of mangroves in Pakistan. In: Restoration of Mangrove Ecosystems. Field, CD. (Ed.). 

International Society for Mangrove Ecosystems, Okinawa,Japan. pp. 126-159. 
Saenger, P. and Siddiqi, N.A. (1993). Land from the sea: the mangrove afforestation program of Bangladesh.JoMrfiu/ of 

Ocean and Coastal Management 20: 23-39. 
Scott, D.A. (1989). /I Directory of Asian Wetlands. lUCN, Gland, Switzerland and Cambridge, UK. 1181 pp. 
Seidensticker.J. and Hai, M.A. (1983). The Sundarbans Wildlife Management Plan: Conservation in the Bangladesh Coastal 

Zone. lUCN, Gland, Switzerland. 120 pp. 



South and Southeast Asia 73 

Siddiqi, N.A. (1994). The importance of mangroves to the people m the coastal areas of Bangladesh. In: Proceedings of the 

VII Pacific Inter- Congress Mangrove Session, Mangrove Session. Mangrove Ecosystems Proceedings No. 3. International 

Society for Mangrove Ecosystems, Okinawa, Japan, pp. 5-10. 
Silapathong, C. (1992). Utilisation combinee d'un systeme d'lnforination geographique et de la teledetection pour le 

suivi et I'amenagement des mangroves de Thailande. PhD Thesis, Paul Sabatier University, Toulouse, France. 134 pp. 
Silapathong, C. and Blasco, F. (1992). The application of geographic information systeins to mangrove forest 

management; Khlung, Thailand. Asian Pacific Remote Sensing Journal 5: 97-104. 
Sin, M.S. (1990). Mangroves in Kampuchea. Forest Ecology and Management. Vol. 33-34. pp. 59-62. 
Soemodihardjo, S. (1 986) . Indonesia. In: Mangroves of Asia and the Pacific: Status and Management. Umali, R.M., Zamora, 

RM., Gotera, R.R.,Jara, R.S., Camacho, A.S. and Vannucci, M. (Eds). UNESCO/UNDP, Manila, Philippines. 

pp. 89-129. 
Soemodihardjo, S. , Wiroatmodjo, P. , Abdullah, A. , Tantra, I .G.M. and Soegiarto, A. ( 1 993) . Condition, socio-economic 

values and enviromiiental significance of mangrove areas. In: Tlie Economic and Environmental Values of Mangrove 

Forests and their Present State of Conservation in the South-East Asia/Pacific Region. Clough, B. (Ed.). Mangrove 

Ecosystems Technical Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 17-40. 
Umali, R.M., Zamora, P.M., Gotera, R.R.,Jara, R.S., Camacho, A.S. and Vannucci, M. (1986). Mangroves of Asia and the 

Pacific: Status and Management. UNESCO/UNDP Manila, Philippines. 538 pp. 
UNDP-UNESCO (1991). Tlie Integrated MuUidisciphnary Survey and Research Programme of the Ranong Mangrove 

Ecosystem. Project RAS 86/120. National Research Council of Thailand, Bangkok, Thailand. 183 pp. 
Untawale, A.G. (1986). India. In: Mangroves of Asia and the Pacific: Status and Management. Umali, R.M., Zamora, P.M., 

Gotera, R.R.,Jara, R.S., Camacho, A.S. and Vannucci, M. (Eds). UNESCO/UNDP Manila, Philippines, pp. 51-87. 
Untawale, A.G. (1994). Significance of mangroves for the coastal commumties of India. In: Proceedings of the VII Pacific 

Inter- Congress Mangrove Session, Mangrove Session. Mangrove Ecosystems Proceedings No. 3. International Society for 

Mangrove Ecosystems, Okinawa, Japan, pp. 15-20. 
Zamora, P.M. (1987). Mangrove. In: The Coastal Environmental Profile of Brunei Dandssalam: Resource Assessment and 

Management Issues Chua, T.-E., Chou, L.M. and Sadorra,M.S.M. (Eds). ICLARM Technical Reports. Fisheries 

Department, Ministry of Development, and International Center for Living Aquatic Resources Management, Brunei 

Darussalam and Manila, Philippines, pp. 28-42. 
Zamora, P.M. (1992). Mangrove resources of Brunei Darussalam: status and management. In: Tlie Coastal Resources of 

Brunei Darussalam: Status, Utilization and Management. Silvestre, G., Matdanan, HJ.H., Sharifiaddin, P.H.Y., De Silva, 

M. W.R.N, and Chua, T.-E. (Eds). ICLARM Conference Proceedings. Department of Fisheries, Ministry of Industry 

and Primary Resources, and International Center for Living Aquatic Resources Management, Bandar Seri Begawan, 

Brunei Darussalam and Manila, Philippines, pp. 39-58. 



14 



World Mangrove Atlas 




2 



73 

8 



a 



c 

a 

4-1 
EA 

3 






South and Southeast Asia 



75 




01 

3 
O 
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c 

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16 



World Mangrove Atlas 




Map 5.3 Vietnam, Southern China and Hong Kong 



South and Southeast Asia 



77 




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a 



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a 



e3 



a 
'£ 
O 

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a 

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78 



World Mangrove Atlas 



-20-N- 



500 km 




125 'E 



Map 5.5 The Philippines 



South and Southeast Asia 



19 




Map 5.6 Sumatra and Peninsular Malaysia 



80 



World Mangrove Atlas 




Map 5.7 Borneo and Java 



South and Southeast Asia 



81 






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6 



Australasia 



The Australasian region includes Australia, Papua New Guinea, New Zealand, and the islands of the South 
Pacific. Australia, southern Papua New Guinea, New Caledonia and New Zealand can be considered as part 
of the Australian Continental Plate; while northern Papua New Guinea, and the western and central Pacific 
Islands represent the western Pacific Plate (Duke, 1992). This region is home to a great diversity of mangrove 
species, including some endemic species (Table 6.1). The greatest concentration is found in northern Australia 
and southern Papua New Guinea, which together share 45 species, in Western Samoa the number of species 
drops to three and in New Zealand there is only one species, AiHcennia marina. Duke (1992) suggests that there 
are no obvious barriers to the dispersal of propagules within this region, although others would argue that the 
distances between islands present large, and in some cases, insurmountable barriers. Whichever view is correct, 
there are some remarkable discontinuities of species. 

One interesting issue is the presence of Rhizophora samoensis in the southwestern Pacific and its apparent 
western migration across the southern Pacific. This species has been recorded in New Caledonia, Fiji, Tonga 
and Samoa (Tomlinson 1986). Tomhnson also states that Rhizophora samoensis is scarcely distinguishable in its 
morphology from Rhizophora mangle. It is usual to maintain that R. samoensis and R. mangle are different species 
and Tomlinson maintains that it is more than useful to retain the separate names. He does, however, speculate 
that the presence of/?, samoensis in the southern Pacific may represent the spread of i?. mangle westwards. EUison 
(1995a) takes a more radical approach and states.that R. samoensis is merely a synonym for R. mangle. It is generally 
agreed that R. mangle occurs on Oahu, Hawaii, but it, and several other mangrove species are considered to have 
been introduced by early travellers. There are several other examples in the Pacific of mangrove species being 
introduced beyond their natural limit. 

The total area of mangroves in this region is some 18,789 sq km. This represents some 10% of the global total 
area. The great majority, some 90%, of the region's mangroves are restricted to Australia and Papua New Guinea. 

Duke (1992) indicates that Papua New Guinea has fourteen fewer species of mangrove in the north than in 
the south and he expresses the opinion that, in the light of current evidence, Papua New Guinea marks a fusion 
boundary between two previously isolated and different mangrove floras. The biogeography of this region and 
the reasons for the floral discontinuities of mangrove species are still a matter of debate (Duke, 1992; Ellison, 
1995a; Stoddart, 1992). 



Australasia 



83 



Table 6.1 Mangrove species list for Australasia 





1 
1 

< 


1 
1 

to 
1 


1 
.5 

JO 

1 


1 


1 

■s 

s 
1 


o 

-sl 


iZ 


£ 

J 


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I 

Z 


I 

z 


3 


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1 

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1 
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B 

c 

5 


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E 

c 

1 


Acanthus ebracteatus 




































Acanthus ilicifolius 






• 






























Acrostichum aureum 




































Acrostichum speciosum 






• 




• 


























Aegialitis annulata 




• 


• 




■ 


























Aegiceras comiculatum 




• 


• 




• 
















• 










Avicennia alba 












• 




• 






• 




• 










Avicennia Integra 






• 






























Avicennia manna 




• 


• 




• 








• 


• 






• 






• 




Avicennia officinalis 




































Avicennia rumphiana 




































Bruguiera cylindrica 




































Bruguiera exaristata 




• 
































Bruguiera gymnorrhiza 


• 








• 


• 


• 


• 


• 




• 




• 


• 




• 


• 


Bruguiera halnesii 




































Bruguiera parviflora 


























• 






• 




Bruguiera sexangula 


















• 








• 










Camptostemon schultzii 




































Ceriops australis 




































Ceriops decandra 




































Ceriops tagal 




• 








• 






• 




• 




• 






• 




Cynometra iripa 




































Diospyros ferrea 






- 






























Dolichandrone spathacea 




































Excoecaria agallocha 






• 




• 


• 


• 


• 


• 




• 






• 




• 




Heritiera littoralis 












• 


• 


• 


• 




• 


• 




• 




• 




Lumnitzera littorea 












• 


• 


• 


• 




• 






• 


• 


• 




Lumnitzera racemosa 










• 


























Lumnitzera x rosea 




































Nypa fruticans 












• 




• 






• 














Osbornia octodonta 




• 
































Pemphis acidula 




































Rhizophora apiculata 












• 




• 


• 




• 










• 




Rhizophora mucronata 












• 




• 






• 










• 




Rhizophora samoensis 


• 












• 














• 






• 


Rhizophora stylosa 




• 






• 


• 


• 


• 












■ 


• 


• 




Rhizophora x lamarckii 




































Rhizophora x selala 














• 






















Scyphiphora hydrophyllacea 












■ 










• 














Sonneratia alba 












• 










• 










■ 




Sonneratia caseolaris 
































• 




Sonneratia lanceolata 




































Sonneratia ovata 




































Sonneratia x gulngai 
































• 




Sonneratia x urama 




































Xylocarpus granatum 












• 


• 




• 




• 






• 




• 




Xylocarpus mekongensis 


• 










• 


• 


• 


• 




• 






• 




• 


• 



Country sources 



American Samoa Ellison, 1995a 

Australia, southwest (Eucia to Broome, Western Australia) Duke, 1992* 

Australia, northwest (Broome to Archer Basin. Queensland) Duke, 1992* 

Australia, northeast (Archer Basin to Curtis Island, Queensland) Duke, 1992* 

Australia, southeast (Curtis Island to EucIa) Duke, 1992* 

Federated States of Micronesia Ellison, 1995a 

Fiji Ellison, 1995a 

Guam Ellison, 1995a 

New Caledonia Ellison, 1995a 



New Zealand 

Palau 

Papua New Guinea 

Solomon Islands 

Tonga 

Tuvalu 

Vanuatu 

Western Samoa 



Ellison, 1995a 
Ellison, 1995a 
Duke, 1992 
Ellison, 1995a 
Ellison, 1995a 
Ellison. 1995a 
Ellison, 1995a 
Ellison, 1995a 



Australia has been subdivided into four regions. The number of mangrove species in each region is closely correlated with latitude and rainfall (Duke, 1992), See 
the relevant regional maps for the location of the limits to these regions 



84 World Mangrove Atlas 

Australia Maps 6.1 and 6.2 



Land area 


7,713,360 sq km 


Total forest extent (1990) 


398,370 sq km 


Population (1995) 


18,338,000 


GNP(1992) 


17,070 U5$ per capita 


Mean monthly temperature ranges: 




Darwin (sea temperature range) 


25-28°C 


Dampier (sea temperature range) 


18-32°C 


Townsville (sea temperature range) 


23-32°C 


Melbourne (sea temperature range) 


14-17°C 


Mean annual rainfall (Darwin) 


1,536 mm 


Mean annual rainfall (Dampier) 


311 mm 


Mean annual rainfall (Townsville) 


1,151 mm 


Mean annual rainfall (Melbourne) 


659 mm 


Spnng tidal amplitude (Darwin) 


1,2-6,8 m 


Spring tidal amplitude (Dampier) 


0,94,5 m 


Spring tidal amplitude (Townsville) 


0.5-2,8 m 


Spnng tidal amplitude (Melbourne) 


0,1-0,9 m 


Alternative estimate of mangrove area (Galloway, 1982) 


1 1,500 sqkm# 


Area of mangrove on the map 


9,695 sq km 


Number of protected areas with mangrove 


180 



The mangrove flora of Australia is one of the richest in the world: some thirty-nine species have been recorded. 
The mangrove floristics and biogeography have been described by Hutchings and Saenger (1987), Galloway (1982) 
and, most recendy, Duke (1 992) . Hutchings and Saenger (1 987) divided the country into twelve regions and later 
modified it to thirteen while Galloway (1982) described the mangrove distribution by State. Duke (1992) divided 
AustraUa into four main regions: northwest, southwest, northeast and southeast. As far as mangrove distribution 
is concerned, some of these regions merge into other nearby countries, such as New Caledonia, but these are 
described in separate accounts. For purposes of simplicity the approach used by Duke (1992) wiU be described. 

The mangroves of Australia are distributed around most of the mainland coast, except for a region in 
southwestern Australia, the Great AustraUan Bight. They do not occur in Tasmania. The largest number of species 
occurs in the northern and northeastern coastlines. The concentration of species and the large area of mangroves 
in this region can be attributed to the tropical climate of high temperatures and good rainfall in northern 
Australia. As one moves south on both the east and west coasts there is a progressive decline in the number of 
species of mangrove. ^i'ifen«ia marina is the sole species present in the state of Victoria. This probably reflects 
changes in average temperature of both air and water. However, the greater southward extent of mangroves on 
the east coast is most likely due to the east coast being appreciably wetter than the west coast. These east coast 
mangroves are actually at the highest latitude of any mangrove communities in the world (38°45'S) and are 
significantly further south than the mangroves of New Zealand (38°03'S). It has been suggested that the 
concentration of species in the northern part of Austraha may be because the region was the centre of origin 
of mangroves and that the coastline configuration, with numerous estuaries and regions sheltered by the presence 
of the Great Barrier Reef, provide an ideal setting for mangroves. 

The estuaries of northern AustraUa have been extensively surveyed, and Duke (1992) suggests that there is a 
significant influence of freshwater runoS"and estuary size on the composition of mangrove floras in this region. 
It IS generally considered that large estuaries have more species because they offer larger amounts of habitat, 
but the influence of the saUnity of the water is also an important factor. 

Direct use of inangroves in Australia is not large and vast areas of mangrove remain in a pristine state. The 
Aboriginal inhabitants of Australia had, and in some places still have, many uses for the products that can be 
derived from mangroves. However, the sustainable use of mangroves has been on a small scale because the 
Aboriginals were essentially a non-agricultural nomadic community. Exploitation of the mangroves with less 
regard for preservation came with the European colonists. They cleared areas of mangroves for community 
development but the use of mangroves for timber never developed because there was a plentifial supply of 
timber from terrestrial forests. Today, mangroves are still being cleared for urban development, ports, airports 
and tourist resorts, but as the population density in the northern part of AustraUa is very low, the impact on the 
overall area of mangroves in Australia remains small. 

Map reference 

The Australia mangrove mapping information in this product is © Coirunonwealth Copyright, AUSLIG: Australia's 
national mapping agency. 1995 AH rights reserved. These data are derived from the 1:250,000 National Topographic Map 
Series and are thus from various sources and ages. 

AUSLIG (1995). 1:250,000 digital coverage of mangroves from: TOPO250K CEODATA. The Australian Geographic 
Database Program: GEODATA. Australian Surveying and Land Information Group, ACT Australia. 



Australasia 85 

The South Pacific Maps 6.3 and 6.4 

This area is composed of the countries and territories of the South Pacific Commission and the South Pacific 
Regional Environment Programme with the addition of New Zealand. A review of the taxonomy, distribution 
and conservation of mangroves in this region has recently been undertaken by Ellison (1995a, 1995b). In the 
area of the present map there are 21 species of mangrove and three hybrids. 

The scientific information about mangroves in the Pacific islands tends to be generally poor and not well 
documented, though the local knowledge of mangroves in some countries is very detailed. To the east of Samoa 
there are no naturally occurring mangroves, though they have been introduced in Hawaii and Tahiti. The greatest 
species diversity and area of mangroves is in the Solomon Islands. The next largest areas of mangroves are in 
Fiji, where 90% of the mangroves occur on Viti Levu and Vanua Levu,and New Caledonia, though the number 
of species is much reduced. Four species do not extend eastward beyond the Solomon Islands to the rest of the 
Pacific Islands: Aegiccras comiadatum, Avicennia alba, Osbomia octodonta and Sonnemtia xgulngai. In New Caledonia, 
Fiji, Tonga and Samoa, Rhizophora samoensis occurs and this may represent the westward spread of R. mangle 
from the Americas. The southern limit of mangroves is New Zealand, where the sole species is Avicennia marina. 
It occurs in the harbours and estuaries of the northern third of the North Island. 

Mangrove areas in the Pacific have been used traditionally for fishing and collecting crabs. Mangrove timber 
is extensively used for firewood and construction of houses and boats. As in other parts of the world, mangroves 
are being removed for coastal development. In the Solomon Islands, Western Samoa, American Samoa and 
Tonga, legislation exists to control the use of mangroves but is not always exercised. In Vanuatu there is no 
legislation specifically relating to the protection of mangroves. Fiji has had a long history of mangroves being 
considered as part of the national forest reserve but in 1 975 mangroves were placed under the jurisdiction of 
the Department of Lands and Survey and usage was not regulated in a systematic fashion. Today, mangroves 
have little legal protection in Fiji and significant areas have been degraded. 

In New Zealand the monospecific mangrove ecosystem is of particular interest because it is very close to the 
southern limits of world mangrove distribution and has a relatively simple structure. Mangrove productivity in 
New Zealand is considered to be as great as the more complex mangrove ecosystems of the tropics. Infilling 
for agriculture and commercial land development has led to significant loss of mangrove areas. Recent legislation 
in New Zealand has gready enhanced the management of mangrove areas. 

Federated States of Micronesia 

Land area 701 sq km 

Population (1995) 107,900 

GNP(1992) 1,500 US$ per capita 

Mean monthly temperature range (Pohnpei) 26-27''C 

Mean annual rainfall 4,859 mm 

Spring tidal amplitude (Palau) 0.3-1.8 m 

Spring tidal amplitude (Truk) 0.3-0.7 m 

Spring tidal amplitude (Yap Islands) 0.0-1 .5 m 

Alternative estimate of mangrove area (Ellison, 1995b) 86 sq km# 

Area of mangrove on the map (Yap only) 10 sq km 

Number of protected areas with mangrove 

Map reference 

Data were available for Yap only, taken from USDI (1983) based on aerial photographs of 1969 with field checking in 
1980. 

USDI (1983). Topographic map of the Yap Islands (Waqab), Federated States of Micronesia. 1:25,000. United States Department 
of the Interior, Geological Survey. 



86 World Mangrove Atlas 

Fiji 

Land area 18,270 sq km 

Total forest extent (1990) 9,350 km 

Population (1995) 762,000 

GNP(1992) 2,070 US$ per capita 

Mean monthly temperature range 20-30°C 

Mean annual rainfall 2,974 mm 

Spring tidal amplitude (Wairiki creek) 1.3 m 

Alternative estimate of mangrove area (Anon 1993) 385 sq km# 

Area of mangrove on the map 517 sq km 

Number of protected areas with mangrove 1 

Map reference 

The remaining indigenous forest in Fiji was digitised from a 1:500,000 scale forest cover map, prepared by the Ministry 
of Forests, Fiji, from a 1985 survey. Forest types were added with the help of the Maruia Society, Auckland, New Zealand, 
whose staff generously prepared a suimnary forest map based on the Fiji Forest Inventory carried out in 1966-9 and 
published in 1972, in 29 map sheets at 1:50,000 by the Directorate of Overseas Surveys, London. 

Guam 

Land area 1 ,478 sq km 

Population (1995) 183,152 

Mean monthly temperature range 25-31 °C 

Mean annual rainfall ' 2,362 mm 

Spnng tidal amplitude 0.0-0.5 m 

Alternative estimate of mangrove area (Ellison, 1995b) 0.7 sq km 

Area of mangrove on the map 94 sq km# 

Number of protected areas with mangrove 

Map references 

Mangroves copied from Randall and Eldredge (1976) onto a 1:100,000 base map (USDA, 1983). Onginal source: 1:4,800 
aenal photos. Infonnation kindly supphed by Dr Charles Birkeland, University of Guam. CoastUne and nvers digitised 
from USDA (1983). 

Randall, R.H. and Eldredge, L.G. (1976). Adas of the Reefs and Beaches of Guam, with Appendix: Estuarine and mangrove 
shorelines (by M.J. Wilder). Coastal Zone Management Section, Bureau of Planning, Government of Guam,Agana, 
Guam. 191 pp. 

USDA (1983). Island (/Guam. Approximately 1:100,000 scale. Soil Conservation Service, US Department of Agriculture. 

New Caledonia 

Land area 18,576 sq km 

Total forest extent ( 1 990) 9,800 sq km 

Population ( 1 995) 1 64, 1 73 

Mean monthly temperature range (Noumea) 1 9-26°C 

Mean annual rainfall (Noumea) 1,020 mm 

Mean annual rainfall (Poindimie, east coast) 2,687 mm 

Spnng tidal amplitude 4 1 ,5 m 

Alternative estimate of mangrove area (Ellison, 1995b) 203 sq km 

Area of mangrove on the map 456 sq km# 

Number of protected areas with mangrove 

Map reference 

ORSTOM (1981). Atlas de la Noiwellc Calcdonie et Depcndances. 1:1,000,000. Office de la Recherche Scientifique et 
Techmque Outre-Mer, Pans, France. 



Australasia 



87 



New Zealand 



Land area 

Total forest extent (1990) 

Population (1995) 

GNP(1992) 

Mean monthly temperature range (sea) 

Mean annual rainfall (Auckland) 

Spnng tidal amplitude (Auckland) 

Alternative estimate of mangrove area (Hackwell, 1989) 

Area of mangrove on tfie map 

Number of protected areas with mangrove 



270,990 sq km 

75,000 sq km 

3,552,000 

12,000 US$ per capita 

15-20°C 

775 mm 

0,3-3 2 m 

194 sq km 

287 sq km# 

1 



Map references 

Mangroves were copied from NZ topographic map series (Department of Lands and Survey) (various) onto a 1:700,000 
base map before digitismg. Source data from these maps was aerial photography undertaken between 1960 and 1982. 
Department of Lands and Survey (1979-85) 1:50,000 NZMS 260. Department of Lands and Survey New Zealand. 
Deparmient of Lands and Survey (1968-85) 1:63,360 NZMS 1. Department of Lands and Survey, New Zealand. 

Solomon Islands 



Land area 

Total forest extent (1990) 

Population (1995) 

GNP(1992) 

Mean monthly temperature range 

Mean annual rainfall 

Spring tidal amplitude 

Alternative estimate of mangrove area (Ellison, 1995b) 

Area of mangrove on the map 

Number of protected areas with mangrove 



28,900 sq km 

24,000 sq km 

378,000 

710 US$ per capita 

27-31°C 

3,048 mm 

0,4-0.9 m 

642 sq km# 

No data 





Map reference 

No data 



Tonga 



Land area 

Population (1995) 

GNP(1992) 

Mean monthly temperature range (Vava'u) 

Mean annual rainfall 

Spring tidal amplitude 

Alternative estimate of mangrove area (Ellison, 1995b) 

Area of mangrove on the map (Tongatapu only) 

Number of protected areas with mangrove 



750 sq km 

99.000 

1,350 US$ per capita 

24-27°C 

875 mm 

0.3-1 .4 m 

1 sq km# 

3.3 sq km 

1 



Map reference 

Data for Tonga taken from D.O.S. (1971), based on aenal photographs taken m 1968 and field checked m 1972. 
D.O.S. (1971). Tongatapu Island, Kinj^dom of Ton^a. 1:50,000. Series X773 (D.O.S. 6005) Sheet TONGATAPU, Edition 
1-D.O.S. 1971 (reprinted 1976). Directorate of Overseas Surveys, UK and Mimstry of Lands and Survey,Tonga. 



88 World Mangrove Atlas 

Vanuatu 

Land area 12,190 sq km 

Total forest extent ( 1 990) 9, 1 40 sq km 

Population (1995) 169,000 

GNP(1992) 2,900 US$ per capita 

Mean monthly temperature range (Vila) 22-27°C 

Mean annual rainfall 2,103 m 

Spnng tidal amplitude 0.3-1 .6 m 

Alternative estimate of mangrove area (Ellison, 1995b) 28 sq km 

Area of mangrove on the map 1 6 sq km# 

Number of protected areas vwith mangrove 

Map reference 

Data extracted from relevant vegetation maps m Quantin (1972). (Mangroves are only shown hi Vate (1250 000) lie 
Emae (1:100,000), Malikolo (1:200,000), Epi (1:200,000), lies Torres (1:100,000), lies Banks (1:100 000) lie Aruwa 
(1:100,000).) 

Quantin, P. (\972). Archipel des Nouvelks-Hcbrides. Atlas dcs Sols et de Quelques donnees du Milieu Naturel. 1 : 100,000-1 :200,000. 

Office de la Recherche Scienafique et Technique Outre-Mer, Paris, France. 

Western Samoa 

Land area 2,840 sq km 

Population ( 1 995) 1 59,000 

GNP(1992) : 940 U5$ per capita 

Mean monthly temperature range (Apia) 25-27°C 

Mean annual rainfall 2,800 mm 

Spnng tidal amplitude <0.5 m 

Alternative estimate of mangrove area (Ellison, 1995b) 7 sq km# 

Area of mangrove on the map No data 

Number of protected areas with mangrove 

Map reference 

No data 



Papua New Guinea Map 6.4 

Land area 462,840 sq km 

Total forest extent ( 1 990) 360,000 sq km 

Population (1995) 4,344,000 

GNP(1992) 950 US$ per capita 

Mean monthly temperature range (Port Moresby) 27-28°C 

Mean monthly temperature range (Madang) 26-30°C 

Mean annual rainfall (Port Moresby) 1,01 1 mm 

Mean annual rainfall (Madang) 3.485 mm 

Spnng tidal amplitude (Port Moresby) 6-2.3 m 

Alternative estimate of mangrove area (lUCN, 1983) 4,1 16 sq km 

Area of mangrove on the map 5,399 sq km# 

Number of protected areas with mangrove 3 

Papua New Guinea has large tracts of intact mangrove forest with a high species ciiversity extending over many 
thousands of shore kilometres and, in many regions, penetrating quite deeply inland. In general, mangrove 
development, especially of large stands, is better on the mainland along the southern coast than along the 
northern coast. The northern coast also has fewer species. In the islands, significant stands of mangroves are to 
be found, but they are patchy. Fringing mangroves are widespread where conditions are not too sandy, rocky 
or exposed; most river mouths have concentrations of mangroves. There are large concentrations of mangroves 
in the Gulf of Papua and along the coast of the Central Province. There are also significant stands of mangroves 
in the deltas of the Fly, Ramu and Sepik Rivers. 

Mangroves in Papua New Guinea often consist of narrowly crowned trees, 20-30 metres in height, sometimes 
with extensive above-ground root systems without extensive undergrowth. A structure similar to this is found 
throughout the Indo-Malesian region. However, one distinctive feature of mangroves in Papua New Guinea 
is their development in seasonally dry zones, such as around Port Moresby In these regions the height of the 
trees is reduced, and there is a lower species diversity. 



Australasia 89 

Most mangrove forests in Papua New Guinea occur in sparsely populated regions where they remain largely 
pristine. Mangroves have been used for building materials, firewood, medicinal purposes and the production of 
tannins. Nypa Jmticans remains one of the most useful of the mangroves, and is used for thatching, weaving and 
the production of sugar and ethanol. There has been litde commercial exploitation of mangroves for timber, 
but consideration is being given to the estabhshment of large-scale wood-chipping operations. 

Map references 

Digital mapped data have kindly been provided by the Research School of Pacific and Asian Studies, Australian National 
University, with generous pennission from the Department of Agriculture and Livestock, Papua New Guinea. These 
data are taken from the Papua New Guinea Resource InfonnaQon System, developed by the Australian Coinmonwealth 
Scientific and Industrial Research Organisation. The source data have been generated from extensive field studies, 
extrapolated over the whole country by air photo interpretation of 1:50,000 and 1:80,000 images taken in the 1960s and 
1970s, and mapped at a scale of 1:500,000. Although data are old it is thought that rates of change may not be large in 
this country, while these data are the most accurate available for this country. 

BeUamyJ.A. (1986). Papua New Guinea Inventory of Natural Resources: Population Distribution and Land Use Handbook. Natural 
Resource Series No. 6, CSIRO Division of Water and Land Resources, Canberra. 

Paijmans, K. (Ed.) (1976). New Guinea Vc^^ctatwn. Australian National Umversity Press and CSIRO, Canberra. 



Sources 

Anon. (1993). Country report of Fiji on the econonuc and enviromnental value of mangrove forest and present state of 

conservation. In: Ttie Economic and Environmental Values of Mangrove Forests and their Present State of Conservation in the 

South-East Asia/Pacific Rei^ion. Clough, B. (Ed.). Mangrove Ecosystems Technical Reports. International Society for 

Mangrove Ecosystems, Okinawa, Japan, pp. 135-173. 
Duke, N.C. (1992). Mangrove floristics and biogeography In: Tropical Mangrove Ecosystems. Coastal and Estuarine Series 

41. Robertson, A.I. and Alongi.DM. (Eds) . American Geophysical Umon, Washington DC. pp. 63-100. 
Ellison, J. C. (1995a). Systematics and Distributions of Pacific Island Mangroves. In: Marine and Coastal Biodiversity in the 

Tropical Island Pacific Region. Volume 1: Species Systematics and Information Management Priorities. Maragos,J.E., Peterson, 

M.N.A., Eldredge, L.G., Bardach.J.E. and Takeuchi, H.F. (Eds) . East- West Center, Honolulu, USA. pp. 59-74. 
Ellison, J. C. (1995b). Status report on Pacific Island mangroves. In: Marine and Coastal Biodiversity in the Tropical Island 

Pacific Region. Volume 1: Population Development and Conservation Priori(i«. Maragos, J. E., Peterson, M.N. A., Eldredge, 

E.G., Bardach, J.E. and Takeuchi, H.F (Eds). East- West Center, Honolulu, USA. 
Frodin, D. (1985). The mangrove ecosystem of Papua New Guinea. In: Mangrove Ecosystems of Asia and the Pacific: Status, 

Exploitation and Management. Field, CD. and Dartnall. A. (Eds) . Australian Institute of Marine Science. Queensland. 

Australia. 320 pp. 
Galloway, R.W. (1982). Distribution and physiographic patterns of Australian mangroves. In: Mangrove Ecosystems in 

Australia. Clough, B. (Ed.). Australian Institute of Marine Science and Australian National University Press, 

Canberra. 302 pp. 
HackweU, K.R. (1989). New Zealand Mangroves. Department of Conservation, WeUington, New Zealand. 41 pp. 
Hutchings, P. and Saenger, P. (1987). Ecology of Mangroves. University of Queensland Press, Brisbane, Australia. 388 pp. 
lUCN (1983). Global Status of Mangrove Ecosystems Commission on Ecology Papers No. 3. Saenger, P., Hegerl, E.J. and 

Davie, J.D.S. (Eds). International Union for Conservation of Nature and Natural Resources, Gland, Switzerland. 

88 pp. 
Percival, M. and WomersleyJ.S. (1975). Floristics and ecology of the mangrove vegetation of Papua New Guinea. 

Botany Bulletin No. 8. Department of Forests Papua New Guinea. 96 pp. 
Stoddart, D.R. (1992). Biogeography of the tropical Pacific. Paeific Science 46(2): 276-293. 
Tomlinson, P.B. (1986). The Botany of Mangroves. Cambridge University Press, Cambridge, UK. 413 pp. 



90 



World Manj^roue Atlas 




NORTH WEST CAPE 



120 'E 



130 'E 



Map 6.1 Western Australia 



Australasia 



91 



~V77 T ■^^ ^' 



10-S- 




Great C:Z>=> 
Australian 

Bight 



Wilson's 
Promontory 



150 "E 



Map 6.2 Eastern Australia 



92 



World Mangrove Atlas 




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Australasia 



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7 
The Americas 



Mangroves in the Americas stretch from Mexico, the USA and Bermuda in the north to Peru and Brazil in the 
south. The mangroves of the region have been described in some detail by a number of authors (Suman, 1994; 
Lacerda and Field, 1 993; Lacerda 1 993; Scott and CarboneU, 1 986; Harcourt and Sayer, 1 996; Olsen et al. ,1996). 
Table 7.1 gives the mangrove species found in the Americas, by country. Mangroves are a widespread and 
important resource in most countries of the Americas. On the Atlantic coast, they extend from the United 
States of America to Brazil and on the Pacific coast from Mexico to Peru, including all of Central America and 
the Caribbean. The figures from this atlas suggest that mangroves cover some 49,096 sq km in the Americas, 
which represents some 27% of the total area of mangroves in the world. This figure comes close to the estiinate 
of 28.6% by Lacerda (1993). 

One of the most notable features of the American mangroves is their low diversity when compared to those 
of the Indo-Pacific region. They bear a close affinity to the mangroves of West Africa. In all, there are only 
thirteen native species of mangrove found in the Americas. 

Six functional types of mangrove forest have been described in the New World: fringe, riverine, basin overwash, 
scrub and hammock (Lugo and Snedaker, 1974). Although patterns of zonation and succession have been 
described for many areas these often appear to be highly site specific. Hurricanes are a major natural 
phenomenon affecting mangrove areas, particularly in the Caribbean, and have been observed to cause total 
loss of mangroves from some areas. Recovery of the mangrove forests can take years or decades. 

Mangroves have been used by man in the region from pre-historic times. There is evidence of human use of 
these areas dating back five to six thousand years. Early uses may have included timber harvesting and fishing 
in surrounding waters. Over tiine other uses developed, including collecting oysters and the use of mangroves 
for resins, fibres, dyes and medicine. The first detailed description of mangroves in the Americas, dating from 
the early sixteenth century, was by Gonzalo Fernandez Oviedo y Valdes in his Historia General de las Indias, bias 
Y Tierra-Jirme del Mar Oceano, which includes an entire chapter on mangroves. With the European conquest of 
the Americas came the increased use of mangroves for timber and tannins. 

More recently, important offshore fisheries that include a number of fish species that are dependent on 
mangroves for at least part of their Ufe history, have been developed by a number of countries. However, large 
areas of mangroves are now being cleared for the development of land for agriculture, grazing, urban 
development and the booming tourist industry, as well as for timber and fuel. The preparation of ponds for 
shrimp fanning is another major activity causing loss of mangroves. This activity is not so widespread as it is in 
southeast Asia. Other forms of damage and loss arise from the use of areas of mangroves for solid waste disposal, 
landfill and pollution from agricultural runoff and the oil industry. Unlike southeast Asia, few areas have been 
replanted with mangroves and there has been little silvicultural effort. There is now a wide range of legislation 
in place throughout the region to conserve mangroves including protection of mangrove areas, coastal zone 
inanagement planning and restriction of land clearance, waste disposal and timber cutting. 



Tlie Americas 



95 



Table 7.1 Mangrove species list for the Americas 





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Avicennia bicolor 
















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Avicennia germinans 


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Avicennia schaueriana 










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Conocarpus erectus 


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Laguncularia racemosa 




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Mora oleifera 




























































Nypa fruticans 




























































Pelliciera rhizophorae 




















• 






















• 


















Rhizophora hamsonii 










• 










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Rhizophora mangle 




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Tabebuia palustria 






























• 


























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t Acrostichum danaeifolium exists in most places that Acrostkhum aureum occurs but it is rarely distinguished 
I* Introduced 



Country sources 



Aruba 

Bahamas 

Belize 

Bermuda 

Brazil 

Cayman Islands 

Colombia 

Costa Rica 

Cuba 

Ecuador 

El Salvador 

French Guiana 

Guatemala 

Guyana 



Scott and Carbonell, 1986 

Scott and Carbonell, 1986 

Zisman, 1990 

Scott and Carbonell, 1986 

Kjerfve and Lacerda, 1993 

Scott and Carbonell, 1986 

Alvarez-Leon, 1993b 

Polania, 1993 

Padron eta/., 1993 

Bodero, 1993 

Funes, 1994 

Blasco, this document 

Aragon de Rendon et al., 1994 

Harcourt and Sayer, 1 996 



Hispaniola 

Honduras 

Jamaica 

Lesser Antilles 

Mexico 

Netherlands Antilles 

Nicaragua 

Panama 

Peru 

Puerto Rico 

Surinam 

Trinidad and Tobago 

Turks and Caicos 

United States of America 

Venezuela 



Harcourt and Sayer, 1996 data for Dominican Republic 

Scott and Carbonell, 1986 

Bacon, 1993b; Scott and Carbonell, 1986 

Bacon, 1993b; Scott and Carbonell, 1986 

Lot and Novelo, 1990 

Scott and Carbonell, 1986 

Polanfa and Mainardi, 1993 

D'Croz, 1993b 

Echevarria and Sarabia, 1993 

Scotland Carbonell, 1986 

Scott and Carbonell, 1986, vanous WCMC files 

Bacon, 1993b 

Bacon, 1993b 

Snedaker, pers comm., 1995 

Conde and Alarcon, 1993b 



96 World Mangroue Adas 

Aruba and the Netherlands Antilles (leeward group) Map 7.6 

Aruba and the leeward Netherlands Antilles are a group of three islands close to the Venezuelan coast. All are 
semi-arid, with sparse mangrove development. On Aruba, fringe communities are found along the shore of 
Spaans Lagoon and on some of the barrier islands which lie m a chain along the southwest coast. An important 
mangrove community has also developed m the brackish lake of Bubali Pond, a former salme lagoon now fed 
by fresh water from treated sewage discharges. Curasao only has a few small fringe mangrove communities, 
while Bonaire has important fringing mangroves in the more sheltered bays. (See Lesser Antilles section for 
information on the windward group of the Netherlands Antilles.) 

Aruba 

Land area 193sqkm 

Population (1991) 68,900 

Average monthly temperature range 26-29°C 

Mean annual rainfall 432 mm 

Area of mangrove on the map 4,2 sq km# 

Number of protected areas with mangrove 

Map reference 

ECNAMP - See notes under Lesser Antilles. 

Netherlands Antilles (leeward) 

Land area 732 sq km 

Population (1991) 154,955 

Average monthly temperature range 26-28°C 

Average rainfall range 582 mm 

Area of mangrove on the map 10.51 sq km 

Number of protected areas with mangrove 

Map reference 

ECNAMP - See notes under Lesser Antilles. 

Bahamas Map 7.3 

Land area 1 3,880 sq km 

Population (1995) 277,000 

GNP(1992) 1 1,990 US$ per capita 

Mean monthly temperature range 22-27°C 

Average rainfall range 750-1,500 mm 

Alternative estimate of mangrove area (Snedaker, pers comm ) 2,332 sq km* 

Area of mangrove on the map 2,1 14 sq km 

Number of protected areas with mangrove 10 
* considered to be an underestimate 

The Bahamas constitute an archipelago of some 2,750 islands, cays and rocks spread over some 260,000 sq km 
of ocean. Together with the Turks and Caicos, they stand a litde separate from the true Caribbean islands to the 
south. Mangroves form a major vegetation type on a number of the islands, with particular concentrations on 
Great Inagua, the Bight of Akhns (between Crooked Island and Aklins Island), the western shores of Andros 
and Great Abaco and the north shore of Grand Bahama. There are no major rivers and most of the mangroves 
are coastal or lagoon formations. The islands themselves are relatively dry, and inland the vegetation is typically 
low thorn-scrub with some areas of pine forest. Mud flats or 'swashes', with litde or no permanent vegetation, 
are another important feature in the intertidal zone. Four mangrove species are found throughout the islands. 
Despite their extensive area, there seems to be little pubHshed material describing the mangroves of the islands. 
A number of mangrove sites fall within protected areas and there do not appear to be any major threats. 

Map references 

Maps have been copied onto a 1:1,000,000 base map from three sources: B&B (n.d.) and Sealey and Burrows (1992). 
None of these sources should be considered highly accurate, but better data were unavailable. 

B&B (n.d.). Bahamas North 1:500,000 Road Map. Berndtson and Berndtson PubUcations, Fiirstenfeldbruck, Germany. 
(Used for: Biimm Island - 1:100,000.) 



Tlxe Americas 97 

B&B (n.d.). Bahamas South 1:500,000 Road Map. Berndtson and Berndtson Publications, Ftirstenfeldbruck, Germany. 

(Used for Aklins Island - 1:500,000; Mayaguana - 1:500,000; Great Inagua - 1:500,000; Exuma Cays - 1:500,000; Cat 

Island - 1:500,000; San Salvador - 1:250,000; Long Island - 1:500,000.) 
SealeyN. and Burrows, E.J. (Eds) {\992) . School Atlas for the Commonwealth of the Bahamas. Longm3n Group UK Ltd, Harlow, 

UK. 49 pp. (Used for Grand Bahama - 1 :600,000; Abaco - 1 :650,000; New Providence -1:1 10,000; Andros - 1:730,000.) 

Belize Map 7.2 

Land area 22,960 sq km 

Total forest extent { 1 990) 1 9,960 sq km 

Population (1995) 209,000 

GNP(1992) 2,220 US$ per capita 

Average monthly temperature range 16-33°C 

Mean annual rainfall range (nortfi) 1 ,400-1 ,500 mm 

Mean annual rainfall (soutfi) >4,000 mm 

Spnng tidal amplitude 21-0.3 m 

Alternative estimate of mangrove area (ODA, 1989) 748 sq km 

Area of mangrove on the map 719 sq km# 

Number of protected areas with mangrove 1 1 

Belize has a relatively extensive and varied coastline, with numerous islands and cays associated with its barrier 
reef and three large coral atolls. Mangroves are widespread on the coast, islands and cays. Mangrove communities 
include fringe mangrove forest, which on some cays extends to cover entire islands as overwash formations; 
sparse mangrove communities adjacent to saltmarsh; basin mangrove communities forming in depressions 
behind river levees and beach ridges; and riverine mangrove forests. There are some small freshwater mangrove 
coiTimunities, some distance inland, surrounded by non-mangrove vegetation, which appear to be relict 
formations. The mapping of mangroves and other habitats in Belize is well documented. The low population 
density in Belize means that there is relatively little pressure on the mangrove forests. Conservation efforts are 
being made in Belize to protect the coastal zone and this should lead to increased protection for some mangrove 
areas. The energy absorbing capacity of mangroves is important during tropical storms as this helps to reduce 
erosion on the low islands and the mainland coast, although mangroves are susceptible to considerable damage 
from the largest hurricanes. 

Map reference 

Maps were provided in digital form - this data set is descnbed in Zisman (1992). 

Zisman, S. (1992). Mangroves in Belize: their characteristics, use and conservation. Consultancy Report No 3. Forest 
Planning and Management Project. ODA/Mimstry of Natural Resources, Behnopan, Behze. 152 pp. 

Bermuda Map 7.3 

Land area 53 sq km 

Population (1990) 71,950 

GNP(1991) 24,000 US$ per capita 

Average monthly temperature range 1 7-26°C 

Mean annual rainfall 1,500 mm 

Alternative estimate of mangrove area (Scott and Carbonell, 1986) 0.17 sq km 

Area of mangrove on the map 0. 10sqkm# 

Number of protected areas with mangrove 5 

Bermuda has only three species of mangroves which occupy only a small area. They are of particular interest, 
however, because they represent the most northerly inangroves in the world (32°20'N). These mangroves are 
of the low island type, with sahnity regimes controlled by ground water outflow. There has been some decrease 
in mangrove area this century due to land reclamation, anchorage and harbour development and waste disposal 
but it is doubtful whether the total area of mangroves has ever exceeded 0.25 sq km. 

Map reference 

Mangrove polygons were copied from the 1 : 10,560 six-map series (D.O.S., 1975) onto a c.l :100,000 base map and digitised. 
D.O.S. (1 975) . Bermuda. 1 : 1 0,560 - six sheets. Series: E81 10 (Bda 311) Edition: 2-Bda 1 975. Directorate of Overseas Surveys, 
London, UK. 



98 World Mangrove Atlas 
Brazil Map 7.5 and 7.7 

Land area 8,51 1,970 sq km 

Total forest extent (1990) 5,61 1,070 sq km 

Population (1995) 161,382,000 

GNP(1992) 2,770 U5$ per capita 

Mean monthly temperature range (Maranhao) 25-27°C 

Mean monthly temperature (Santa Catanna) 20°C 

Mean annual rainfall (Maranhao) 2,500 mm 

Mean annual rainfall (northeast) 1,500 mm 

Spring tidal amplitude (Maranhao) 4-8 m 

Spring tidal amplitude (Santa Catanna) 0,2-2 m 

Alternative estimate of mangrove area (Kjerfve and Lacerda, 1993) 13,800 sq km 

Area of mangrove on the map 13,400 sq km# 

Number of protected areas with mangrove 63 

Mangroves cover very large areas in Brazil with a patchy distribution along the 6,800 km of coast. The most 
extensive mangrove areas are in the north, in the states of Amapa, Para, and Maranhao, where very wide tidal 
ranges, combined with high rainfall, encourage their development. Mangroves can extend up to 40 kin inland, 
along estuaries. In these areas, the trees can reach a considerable height and girth, with Avkennia reaching more 
than 1 m in diameter and Rhizophora harriionii being 40 to 45 m tall. The very large amount of fresh water in 
the Amazon estuarine area tends to restrict the distribution of mangroves, although there are many fresh water 
hardwoods found in this region. Around the northeastern coast the rainfall decreases, as does the tidal range. 
Mangroves are stiU widespread along the inside of bays, and along estuaries, where they are dominated by 
Rhizophora mangle which can reach 10 to 20 m in height. Mangroves are more sparsely distributed along the 
southeastern coast from Rio de Janeiro to Santa Catanna, where they are restricted to river deltas, coastal lagoons 
and the inner parts of bays. There are fewer species in these areas, which are dominated by R. mangle. The trees 
rarely exceed 10 m in height. The southernmost mangroves are found at 28°56'S. 

Mangroves have a wide range of different commercial uses, some of which are very important, notably the 
crab, timber and tannin industries. Mangroves have been destroyed in some areas, notably for timber and for 
urban development in the southeast, but large areas remain relatively unthreatened, particularly in the north. 
Salt extraction and manculture are practised on a very small scale, but are not expanding significantly, while 
reclamation for agricultural development is unlikely while there are still extensive areas of forest inland, on 
better soils. The earliest record of legal protection of mangroves in the region dates from 1760, when the King 
of Portugal, concerned about the loss of potential sources of tannin, issued an edict to restrict the cutting of 
mangroves for firewood unless their bark was also utilised. Some recent laws also provide for the protection of 
mangroves in certain areas, although enforcement is far from complete. 

A highly detailed atlas of mangroves for Brazil has been prepared which maps the mangroves of the entire 
coast at 1:250,000, with higher resolution maps for wide areas. These maps have been prepared from aerial 
photography and satellite imagery (Herz, 1991). 

Map reference 

Data are taken from Herz (1991). The 1 ;250,000 maps were photo-reduced prior to digitising and hence the map prepared 
for this adas does not contain the full detail portrayed in the source. 

Herz, R. (1991). Manguezais do Brasil. Institute Oceanografico da Umversidade de Sao Paulo, Sao Paulo, Brazil. 

Cayman Islands Map 7.3 

Land area 259 sq km 

Population (1990) 29,700 

GNP(1992) 25,300 US$ per capita 

Mean annual rainfall (Grand Cayman) 1,400 mm 

Spring tidal amplitude 012 0-5 m 

Alternative estimate of mangrove area (Bacon, 1993b) 75 sq km 

Area of mangrove on the map 71 sq km# 

Number of protected areas with mangrove 1 1 

The Cayman Islands consist of three low-lying limestone islands which, although small in total area, have a 
relatively large area of mangroves. Mangrove lands make up some 36% of Grand Cayman, 40% of Little Cayman 
and 1% of Cayman Brae. Mangroves are fringe communities around the coast, lagoons and saline to brackish 
ponds found on the islands. The largest single community is that of the central mangrove swamp on Grand 



Tlie Americas 99 

Cayman which covers nearly 50 sq km. Extensive loss of the mangroves has occurred as a result of the 1977 
Development Plan for Grand Cayman and many areas have been reclanned for tourist development, mosdy 
for road construction, golf courses, mannas and housing. 

Map reference 

D.O.S. (1978). Cayman Islands. 1:25,000 - four sheets. Series: E821 (D.O.S. 328) Edition: 2-D.O.S. 1978. Directorate of 
Overseas Surveys, UK and Survey Department, Cayman Islands. 

Colombia Map 7.6 

Land area 1,138,910 sq km 

Total forest extent (1990) 540,640 sq km 

Population (1995) 35,101,000 

GNP(1992) 1 ,290 US$ per capita 

Mean monthly temperature range (Baranquilla) 27-28°C 

Mean annual rainfall (Baranquilla) 799 mm 

Spnng tidal amplitude (Pacific) >4 m 

Spring tidal amplitude (Caribbean) 0.3-0.6 m 

Alternative estimate of mangrove area (Alvarez-Leon, 1993b) 3,659 sq km# 

Area of mangrove on tfie map 4,975 sq km 

Number of protected areas witfi mangrove 8 

Colombia has extensive coastlines along the Pacific Ocean and the Caribbean Sea. These two areas are very 
distinctive, with the majority of mangroves occurring in the former (70-80% of total). The Pacific coast harbours 
some ten species of mangroves which form dense high forests, comparable to many of those found in southeast 
Asia. Trees can reach a height of 40 to 50 m and form an almost continuous fringe, sometimes 20 km deep, 
from Cabo Cornentes to the border with Ecuador. By contrast, the much smaller Caribbean mangroves are 
limited in their development by drier conditions and low tidal fluctuations. On the Caribbean coast only five 
species of mangrove are reported. 

Mangrove exploitation for timber by the Spanish began as early as the 16th century. Mangroves have been 
also used for tannin production, but today they are used mainly for firewood, charcoal and construction timber. 
Some mangrove areas have been cleared for aquacultural purposes, notably shrimp farming. In other areas, 
mangroves have been cleared for urban development, or degraded by agricultural contamination. Some parts 
of the Caribbean coast may also be suffering from reduced fresh water inputs arising from inland diversion and 
utilisation of water. Natural processes ot erosion, accretion and siltation along central areas of the Caribbean 
coast have led to rapidly changing mangrove areas in this region. Accretion is also an important process on the 
Pacific coast south of Buenaventura. 

Map reference 

Basic data were derived fi-om Ministerio de Hacienda (1985), with further edits estimated from two basic (1:5,000,000) 
maps provided by Sanchez, Ministerio del Medio Ainbiente (1995) and minor corrections provided by Fran(;:ois Blasco. 

Ministerio de Hacienda (1985). Republica dc Colombia: Mapa de Basques. 1:1,500,000. Produced by the Ministerio de 
Hacienda and Institute Geografico 'Agustin Codazzi'. 

Costa Rica Map 7.2 

Land area 5 1 , 1 00 sq km 

Total forest extent ( 1 990) 1 4,280 sq km 

Population (1995) 3,424,000 

GNP(1992) 2,010 US$ per capita 

Average temperature 26°C 

Mean annual rainfall (Lepanto Golfo de Nicoya) 1 ,654 mm 

Mean annual rainfall (Palmar Sur) 3,676 mm 

Mean tidal range 3.6 m 

Alternative estimate of mangrove area (Polania, 1993) 412 sq km 

Area of mangrove on the map 370 sq km# 

Number of protected areas with mangrove 9 

The Pacific coast of Costa Rica is about five times as long as the Caribbean coast due to a complex structure 
of many embayments, estuaries and gulfs. Mangrove forests occupy about 35% of this coast and make up 99% 
of all of Costa Rica's mangrove area. In the north, mangroves are not highly developed structurally as they have 
a canopy height of only about 20 m due to the low rainfall and a long dry season (December to April). South 



100 World Mangrove Atlas 

of the Golfo de Nicoya, there is a transition zone where the forests are more diverse and better developed, with 
trees reaching a height of 45 m as a result of higher rainfall and a shorter dry season (less than three months). 
The Golfo de Nicoya has an important fin fishery associated with the mangroves, while cockles (Anadara 
tuberculosa and A. similis) are widely exploited coinmercially. Mangroves have been used for timber, charcoal 
and tannin production, but not extensively. Forest clearance for aquaculture, salt production and fuelwood for 
salt crystallisation has led to loss of mangrove areas in the north. To the south, the mangroves of Terraba-Sierpe 
are of considerable interest and have been declared a Mangrove Forest Reserve, with a series of management 
and conservation activities, including sustainable development of charcoal production. 

Map reference 

Institute Geografico Nacional (various dates). Costa Rica. 1:200,000. Instituto Geografico Nacional, San Jose, Costa Rica. 
Individual maps tided as follows: CR2CM-1 Liberia. Edicion 1-IGNCR. Prepared: 1970; CR2CM-2 San Carlos. Edicion 
1-IGNCR. Prepared: 1970, revised: 1988; CR2CM-3 Barra del Colorado. Edicion 1-IGNCR. Prepared: 1970, revised: 
1988; CR2CM-4 Nicoya. Edicion 2-IGNCR. Prepared: 1968, revised: 1988; CR2CM-5 Sanjose. Prepared: 1968, revised: 
1988; CR2CM-6 Limon. Edicion 1-IGNCR. Prepared: 1969; CR2CM-7 Qucpos. Prepared: 1969, revised: 1988; 
CR2CM-8 Talamanca. Prepared: 1970, revised: 1988; CR2CM-9 Coljito. Prepared: 1970, revised: 1988. 

Cuba Map 7.3 

Land area 1 10,860 sq km 

Total forest extent ( 1 990) 1 7, 1 50 sq km 

Population (1995) 11,091,000 

Mean annual temperature and range 25°C (lO-Se'C) 

Mean annual rainfall 1,200 mm 

Spring tidal amplitude 9 m 

Alternative estimate of mangrove area (Padron et al , 1993) 5,569 sq km 

Area of mangrove on the map 7,848 sq km# 

Number of protected areas witfi mangrove 8 

Cuba is the largest of the Caribbean islands. It has a long coastline with numerous bays, lagoons and barrier 
islands. Mangroves cover nearly 5% of the total area of Cuba, making up one quarter of the total forest area. 
They play an important role protecting large parts of the coast from erosion, particularly during tropical storms, 
although coastal erosion processes theinselves are responsible for mangrove loss in some areas. Mangroves are 
not heavily used for timber production, but are increasingly used for fuelwood, notably by the sugar industry. 
During the flowering of the inangroves, particularly Auicennia, over 40,000 bee hives are transported to the 
mangrove areas, particularly on the south coast. Fin and shell fisheries are also important. Human impacts have 
caused industrial and agricultural contamination and some deforestation. The largest single area of mangroves 
occurs on the Zapata peninsula on the south coast which contains very important waterfowl and other wildhfe, 
including the endemic Cuban crocodile, Crocodylus rhombijer. This site is partially protected by legislation. Since 
1980, there has been a mangrove replanting scheme which has planted mangroves over some 257 square 
kilometres. Under the National Forestry Pohcy replanting will continue, while other management plans are 
developed for protection and utilisation of mangrove resources. 

Map reference 

Academia de Ciencias de Cuba (1989). Nuevo Atlas National de Cuba: X Flora y Vegetacion: 1 Vegetacion Actual. 1:1,000,000 
Academia de Ciencias de Cuba. The vegetation map was prepared by Capote Lopez, R.P., Ricardo Napoles, N.E., 
Gonzalez Areu, A. V, Garcia Rivera, E.E.,Vilamajo Alberdi, D. and Urbino Rodriguez,]. 

Dominican Republic and Haiti Map 7.3 

The island of Hispaniola comprises the countries of the Dominican Republic and Haiti. It is second only to 
Cuba in size in the Caribbean. Mangroves are found in both countries, with the largest single areas being along 
the north coast of the Dominican Republic, in the bay areas at Monte Cristi and at Bahia de Samana. In Haiti, 
the main areas for mangroves are along the north coast, east from Cap Haitien and on the west coast, south of 
Gonaives. Widespread destruction of mangrove areas is expected in the Dominican Repubhc arising from 
extensive development for the tourism industry. By contrast, in Haiti, mangroves are one of the least threatened 
ecosystems; they are used for charcoal and polewood, but this is not thought to have a significant impact. 



Tlie Americas 101 

Dominican Republic 

Land area 48,730 sq km 

Total forest extent (1990) 10,770 sq km 

Population ( 1 995) 7,91 5,000 

GNP(1992) 1,040 U5$ per capita 

Mean monthly temperature range 24-27''C 

Mean annual rainfall 1,400 mm 

Alternative estimate of mangrove area (Alvarez, 1994) 325 sq km# 

Area of mangrove on the map (696 sq km) 

Number of protected areas with mangrove 6 

Map reference 

Data taken from map in Schubert (1993) which is approximately 1:2,000,000, based on 1984 aerial photographs. 
Schubert, A. (1993). Conservation of biological diversity in the Dominican Republic. Oryx 27: 1 15-121. 

Haiti 

Land area 27,750 sq km 

Total forest extent ( 1 990) 230 sq km 

Population (1995) 5,968,000 

GNP(1991) 380 US$ per capita 

Mean monthly temperature range 25-29°C 

Mean annual rainfall 1,321mm 

Area of mangrove on the map 1 34 sq km# 

Number of protected areas with mangrove 

Map reference 

The full reference for the source map is unavailable, but its source data include aerial photographs from 1978 taken at 
1:40,000 and 1982 agnculture maps. 

Unknown (n.d.). Atlas d'Haiti. Planche 8 Ecologie, by Roca, P. -J. 1:1,000,000. Full reference unavailable. 

Ecuador Map 7.6 

Land area 283,560 sq km 

Total forest extent (1990) 1 19,620 sq km 

Population (1995) 11,822,000 

GNP(1992) 1,070 US$ per capita 

Mean annual temperature (Motaje-Santiago-Cayapas) 23°C 

Mean annual temperature (Guayas Basin) 25''C 

Average rainfall range (Motaje-Santiago-Cayapas) 3,000-4,000 mm 

Average rainfall range (Guayas Basin) 300-400 mm 

Spnng tidal amplitude 2.5-3 m 

Spring tidal amplitude (Gulf of Guayaquil) 5.29 m 

Alternative estimate of mangrove area (Bodero, 1993) 1,621 sq km 

Area of mangrove on the map 2,469 sq km# 

Number of protected areas with mangrove 4 

In Ecuador, inangroves are concentrated around river estuaries, with the largest single area being around the 
Guayas River estuary and Guayaquil Gulf (1,099 sq kin). The other major area lies close to the Colombian 
border in the north, the Santiago-Cayapas-Mataje estuarine zone, where very high rainfall provides for some 
of the best developed mangroves in the Pacific, with trees reaching over 50 m in height. Away from the estuaries, 
substantial areas of the coast are steeply shelving and provide Httle opportunity for mangrove development. 
Riverine mangroves are the most structurally developed, due to the high levels of freshwater input. Two other 
structural forest types occur: basin forests, flooded by the highest tides and characterised by high salinity, and 
fringe mangroves which include the bulk of mangroves in the country. As in other countries in the region, 
mangroves have been used for timber, charcoal and tannins, but in Ecuador, the most important uses have been 
the conversion of mangrove land for aquaculture, salt production and agriculture. The creation of shrimp farms 
has led to the conversion of some 400 sq km of mangrove. A further 400 sq km has been converted for catde 
grazing. The shrimp industry has been extremely profitable to Ecuador, but a large number of ponds are now 
unproductive due to salinisation and acidification. The creation of new ponds is now largely restricted to tidal 
flats. Scallops and crabs provide important shellfish products from the mangroves, with the river estuaries in the 
north producing 2 to 2.5 million scallops per month. Estimates as to the total area of mangrove in Ecuador 
vary considerably; two extremes are given in the table, but other estimates include 2,377 sq km (in 1987) and 



i02 World Mangrove Atlas 

1,776 sq km (in 1991) (Harcourt and Sayer, 1996). In the absence of further details as to how these areas were 
calculated, it is difficult to assess which is the most accurate. 

Map reference 

CLIRSEN/DINAF (1991). Rcpublica del Ecuador - Mapa Forestal. 1:1,000,000. Centro de Levantarnientos Integrados de 
Recursos Naturales por Sensores Remotos (CLIRSEN) and Direccion Nacional Forestal (DINAF). 

El Salvador Map 7.2 

Land area 21,040 sq km 

Total forest extent (1990) 1,230 sq km 

Population (1995) 5,768,000 

GNP(1992) 1,170 US$ per capita 

Mean monthly temperature range (San Miguel) 25-28°C 

Mean annual rainfall (San Miguel) 1 .700 mm 

Alternative estimate of mangrove area (Funes, 1994) 268 sq km# 

Area of mangrove on the map 446 sq km 

Number of protected areas with mangrove 2 

El Salvador is the smallest of the Central American countries and the only one without a Caribbean coastline. 
High population densities have led to massive deforestation inland and mangroves now represent one of the 
major forest types in the country. Mangroves are found all along the coast but are concentrated in the coastal 
lagoons and estuaries. The most notable areas are the Punta San Juan and the Rio Lempa estuaries in the centre 
and east of the country, and Golfo de Fonesca on the Nicaraguan border. In the west, mangrove communities 
are found behind the Barra de Santiago Lagoon. Mangroves have been exploited for tannins, charcoal and 
timber and may be threatened by agricultural encroachment and the development of salt pans and shrimp 
ponds, although by law they belong to the government. The area of mangrove presented on the map is likely 
to be a considerable over-estimate and includes related habitats. A government estimate based on a forest 
inventory between 1973 and 1975 put the total area of mangroves at 344 sq km, while a more recent study, 
based on aerial photographs, showed a 22% decrease. The latter study showed a total mangrove area of 268 sq 
km, but pointed to the original area of 459 sq km of which some 60% was actual mangrove habitat, with much 
of the remainder being made up of agricultural land on former mangrove areas, salt flats and open water. It is 
likely that the rate of mangrove loss is accelerating. 

Map reference 

Ministeno de Agricultura y Ganaderia (1981). Mapa dc Vegctacion Arborca de El Salvador. 1 : 200,000 . Mirusterio de Agricultura 
y Ganaderia, Direccion General de Recursos Naturales Renovables, Programa Determinacion del Uso Potential del 
Suelo. 



French Guiana Map 7.s 

Land area 90,000 sq km 

Population (1995) 114,000 

Mean annual rainfall 2,000 mm 

Average tidal range 2 m 

Alternative estimate of mangrove area (Saenger et al., 1983) (55 sq km)# 

Area of mangrove on the map (951 sq km) 

Number of protected areas with mangrove 

The coastline of French Guiana is highly dynamic, with rapid accretion and erosion processes occurring. 
Mangroves are largely fringe communities occupying a thin band along most of the coastline, broken by a few 
sandy beaches and rocky headlands. In many areas there appears to be a clear coastal zonation, with Laguncularia 
racemosa on the seaward edge, backed by well-developed stands of Avicennia germinans, typically reaching 5-8 m 
in height. Rhizophora is more closely associated with riverine mangrove communities. Behind the mangrove 
coiTiiTiunities there are typically swamp forests or herbaceous swamps. There is very little threat to the mangroves 
for timber or fuel as the rest of the country is heavily forested. Mangroves are important for the shrimp industry 
and as a nursery for penaeid shrimp larvae. The shrimp industry provides the country's main export and is a 
major source of employment. Estimates of mangrove area vary considerably, which may in part be a function 
of the highly dynamic nature of these communities. 

Map reference 

ORSTOM (1979). Vegetation - La Guyane: Planchc t2. Adas des Departements d'Outre-Mer, Centre d'Etudes de 
Geographie Tropicale - OfEce de la Recherche Scientifique et Technique Outre-Mer, Paris, France. 



The Americas 103 



Case study 



The mangroves of French Guiana: 
a dynamic coastal system 



The three countries commonly known as the Guianas stretch along the South American coast from 
Brazil to Venezuela, between the mouth of the Amazon and the delta of the Orinoco. They harbour 
a set of highly dynamic coastal mangroves. The great instability of the mangroves is almost certainly 
related to the strong coastal currents in this region, which carry heavy sediment loads from the 
Amazon. Sudden and aperiodic mass mortality of the mangroves has been observed in the region 
(Plate 7.1), immediately followed by spectacular coastal erosion, but the exact biophysical mecha- 
nisms causing this are unknown. The case study presented here relates to the mangroves of French 
Guiana near the launching site of Earth Observation Satellites, at Kourou. 

The coastal vegetation of French Guiana is shown in Figure 7.1. The mangroves are not very 
extensive (55 sq km), when compared to those of neighbouring countries such as Surinam (1,150 
sq km) and Guyana (800 sq km). However, their evolutionary trends, community dynamics, 
dominant species {Avicennia germinans), as well as their characterisation from space, may be 
considered typical for this part of the world. 

The general formation of these mangroves (sec Figure 7.2) is coastal, a few metres to a few 
kilometres in width. This fringe includes only two species of trees, the commonest being Avicennia 
germinans, a fast growing tree (about 1 m per year) usually creating monospecific stands of about 
5 m to 8 m in height, together with Laguncularia racewosa, a pioneering bushy species often 
found on the seaward edge of the mangrove, mixed with Spartina brasiliensis, an American 
saltmarsh species (Graminae) which can be considered as ecologically equivalent to Porteresia 
coarctata in Asia (Bay of Bengal). Competition between Laguncularia and Avicennia is a common 
feature. The latter usually eliminates the former in older mangrove stands. 

This zonation pattern can easily be detected from satellite images. Upstream, along the river 
banks, a further narrow mangrove type can be discriminated with aerial photography. This is a 
common riverine vegetation type with Rhizophora mangle. The appearance of Pterocarpus 
officinalis, a tree with conspicuous buttresses, in the environment is indicative of a classic 
freshwater swamp forest. 

In this densely wooded country the mangroves are not widely utilised. The irregular and 
unexplained cycle of spectacular erosion and accretion does not appear to affect the total areal 
extent of mangroves, which remains almost constant. 

The image presented in Figure 7.3 has been prepared from the combination of SPOT imagery 
with radar satellite imagery (ERS-1). Using these techniques it is possible to distinguish quite fine 
variation in land cover and basic zonation patterns. 



Environmental data 

• Mean annual rainfall >2,000 mm/year 

• Dry season 2 to 4 dry months 

• Mean water salinity 10 to 25%o 

• pH of the topsoil 7 

• Dominant soil type Grey, blueish clay 

• Average tidal amplitude 2 m 

• Average population density About 0.7 people per sq km for the total territory (90,000 sq km) 

• Total areal extent 55 sq km 

• Dominant mangrove type Almost monospecific coastal stands of Avicennia germinans, 

with some Laguncularia racemosa 



104 



World Mangrove Atlas 




Plate 7.1 An illustration of the natural changes in Auicenr^ia mangrove stands. Mass mortality in 

some areas is compensated by the colonisation of areas of new accretion 




Figure 7.1 Coastal vegetation of French Guiana 



The Americas 



W5 




Figure 7.2 Zonation in the mangroves of French Guiana 

A Auicennia germinans belt. Almost monospecific stands. The individual stands have practically 
the same size and the same age 

B Laguncularia {= L) belt in which a grass (S = Spartina brasiliensis) is often found, especially on 
recently accreted mud 




Figure 7.3 A satellite view of the mangroves of Sinnamary estuary in French Guiana. A colour 

classification resulting from a combination of SPOT and ERS-1 



-T 

I 



106 



World Mangrove Alias 




Figure 7.4 A rough interpretation of Figure 7.3 after field trip investigations 

Coastal zone 

1. Dense, mature mangrove stands {Avicennia germmans) 

2. Dying mangroves 

3. Mixed types (mangroves with Rhizophora and freshwater swamp forests) 

4. Naturally destroyed mangove 



Mainland 

5. Thickets and forests on sandy soils 

6. Freshwater swamp forest 

7. Dense evergreen forest 

8. Permanently flooded grassland 

9. Periodically flooded grassland 

10. Water 

1 1 . Town 



Tfie Americas J 07 

Guatemala Map 7.2 

Land area 108,890 sq km 

Total forest extent (1990) 42,250 sq km 

Population ( 1 995) 1 0,62 1 ,000 

GNP(1992) 980 US $ per capita 

Average tidal range (Canbbean) 0.9 m 

Spring tidal amplitude (Pacific) 2 m 

Area of mangrove on the map 161 sq km# 
Alternative estimate of mangrove area (Aragon de Rendon et al., 1994) 160 sq km 

Number of protected areas with mangrove 3 

In Guatemala, the mangroves are concentrated in lagoons along the Pacific coast. The largest single area is 
around the lagoons, estuaries and deltas m the west near the Mexican border and the Rio Ococito. Towards the 
east, significant mangrove areas are found in the Rio Acome estuary, the Monterrico Lagoons and the Rio Paz 
estuary. There are only a few small areas on the Caribbean coast (total 6 sq km) along the Bahia de Amatique 
and the delta of the Rio Chocon. In all areas mangroves are exploited for charcoal, firewood and timber. Shrimp 
farming, shrimp fishing and salt extraction are important, and also represent a threat to many areas. Significant 
areas are also being cleared for agriculture and urban development. There has been a considerable loss of 
mangroves in Guatemala. The total area of mangroves in 1965 was estimated at 234 sq km, and was reduced to 
165 sq km by 1974 and 139 sq km by 1984. These estimates were based on aerial photographs. A subsequent 
figure, calculated from 1988 satellite imagery, of 160 sq km, was pubhshed in the 1989 Forestry Action Plan. 

Map reference 

Data for the source map originate from a 1992 1:250,000 map, Mapa Preliminar de la Cubierta Forcstal de Guatemala. 
Anon. (n.d.). Cubierta Forcstal de la Rcpiiblica de Guatemala - Plan de Accion Forestal de Guatemala. 1:500,000. 

Guyana Map 7.5 

Land area 214,970 sq km 

Total forest extent ( 1 990) 1 84, 1 50 sq km 

Population (1995) 834,000 

GNP(1992) 330 US$ per capita 

Mean monthly temperature range 26-27°C 

Average rainfall range 2,280 mm 

Alternative estimate of mangrove area (GFC/CID, 1989) 800 sq km# 

Area of mangrove on the map (717sqkm) 

Number of protected areas with mangrove 

Mangroves are the only trees in this densely forested country which have been significantly depleted by man. 
They originally covered a large proportion of the country's coastal zone, but have been heavily reclaimed for 
agriculture and cut for fuelwood, charcoal and timber. Major remaining mangrove stands exist between the 
Pomeroon and Waini Rivers to the west, where there are few people. Avicennia germinans tends to dominate on 
the exposed coastal mudflats, where it can grow to 20 to 25 m in height. Rhizophora mangle occurs in more 
sheltered areas. Honey production is important in some areas using the flowers o£A.germinans, while the bark 
o{R. mangle is still used for tannin production. There have been some proposals for the protection of mangroves 
and for afforestation projects as a means of shoreline protection, but there has been little action to date. 

Map reference 

Map data were supplied in digital fonnat from the World Wildlife Fund (USA). These data are of unknown origin, but 
have been published in Olscn et al. (1996). 

Olson, D. M., Dinerstein, E., Cintron, G. and lolster, P. (1996). A conservation assessment of mangrove ecosysteins of Latin 
America and the Caribbean. Report from WWF's Conservation Assessment of Mangrove Ecosystems of Latin America 
and the Caribbean Workshop, December 2-4, 1995, Washington DC, USA. 



108 World Mangrove Alias 

Honduras Map 7.2 

Land area 1 12,090 sq km 

Total forest extent { 1 990) 46,050 sq km 

Population (1995) 5,968,000 

GNP(1992) 550 US$ per capita 

Alternative estimate of mangrove area (Oyuela, 1994) 1,458 sq km# 

Area of mangrove on the map (2,316 sq km) 

Number of protected areas with mangrove 1 2 

In Honduras, substantial areas of mangrove are found on both the Caribbean and Pacific coasts. The Pacific 
coasthne is small and lies entirely within the Golfo de Fonesca which is largely fringed by mangrove 
communities. The Caribbean coastline has wide areas of mangroves associated with lagoons, estuaries and deltas. 
The largest areas are in the west of the country, around the numerous lagoons in that area, notably Laguna de 
Caratasca. Clearance of mangroves for shrimp farms has been extensive and rapid in recent years, but it is 
probable that mangroves play an important role in the local and coinmercial estuanne fishing industry. Estimates 
of mangrove area in Honduras vary considerably from 460 sqkm to 1,450 sq km (see Harcourt and Sayer, 1996). 
It is likely that the mangrove area taken from the map of 2,310 sq km is a considerable over-estimate, errors 
having arisen during the harmomsation of the data from the source map with a different coasthne. 

Map reference 

COHDEFOR (n.d). Mapa de Recursos Costeros. 1:1,000,000. Unpublished map. COHDEFOR. 

Jamaica Map 7.3 

Land area 10,990 sqkm 

Total forest extent (1990) 2 ,390 sq km 

Population (1995) 2,547,000 

GNP(1992) 1,340 US$ per capita 

Mean monthly temperature range (Kingston) 24-27''C 

Average rainfall range (Kingston) 800 mm 

Alternative estimate of mangrove area (Bacon, 1993) 106 sq km# 

Area of mangrove on the map (19 sq km) 

Number of protected areas with mangrove 1 

Mangroves are found around the entire coast of Jamaica, but the largest concentrations are on the south coast, 
associated with a variety of bays, lagoons and inlets. By contrast, the best structural development occurs on the 
north coast with tree densities of forty or more per hectare and with a mean height of 1 6 m (Florida Lands, 
Falmouth). The south coast is much drier and trees rarely exceed 6 m in height. The largest single areas are 
lagoon fringe communities, but a wide range of other community types are found, including basin, estuarine 
and even small overwash commumties on offshore cays. Traditional uses include charcoal production, fishing 
and oyster collecting. Substantial areas have been cleared for urban development and the backs of other areas 
reclaimed for agriculture. About 30% of the original mangrove area is thought to have been lost, and damage 
is continuing with uncontrolled artisan activities, urban sprawl and the dumping of waste. Map 7.3 shows only 
19 sq km of mangrove. This figure was derived from recent sateUite imagery and a large underestimate may 
have arisen from the patchy nature of the mangroves coupled with their scrub-like physiognomy in many areas. 
Both these factors might preclude appearance on satellite images. Interestingly, a similar area was estimated in 
another report which differentiated 'mangrove forest' (22 sq km) from areas described as 'mangrove scrub' (see 
Harcourt and Sayer, 1996). 

Map reference 

Digital data of Jamaica's vegetation were kindly made available by Doug Muchoney and Susan Iremonger of TNC, who, 
together with Robb Wright and in collaboration with the Conservation Data Centre -Jamaica, have compiled vegetation 
cover information for the whole of the country. A written report aded Jamaican Vegetation Types: a New Classification and 
Map (in press), outlines detailed findings of their data collection and research and presents a description of the new 
classification. 



The Americas 109 

Lesser Antilles Map 7.4 

The islands of the Lesser Antilles comprise Anguilla, Antigua and Barbuda, Barbados, British Virgin Islands, 
Dominica, Grenada, Guadeloupe, Martinique, Montserrat, Netherlands Antilles, St Kitts and Nevis, St Lucia, 
St Martin and Barthelemy, St Vincent and the Grenadines, and the US Virgin Islands. 

These islands make up the eastern edge of the Caribbean Sea, stretching from the Virgin Islands in the north 
to Grenada in the south. They include a wide range of high and low islands, some large and heavily forested, 
others dry and barren. The most widespread mangrove communities are small fringing communities associated 
with bays, lagoons and ponds, while the largest communities occur in river mouths. Use of mangroves is highly 
varied between islands, as might be expected, not only from the differences in area and condition of mangroves, 
but also from the differences in economic status and culture. In some islands, mangroves are wdely used for 
timber and fisheries. In many of the islands there is a threat to the mangroves from the rapidly expanding tourist 
industry. The following brief notes are provided on an island by island basis. 
Anguilla is a low-lying island with only a very small area of mangrove. 

Antigua and Barbuda have many mangrove areas on both islands with the largest being the 2.25 sq km 
Hansons Bay (Antigua) swamp, with some trees reaching over 10 m, and the 3.52 sq km forest in Codnngton 
Lagoon (Barbuda). Elsewhere, mangrove areas are mostly fringe and basin communities with scrubby trees. 
Barbados has only one significant mangrove area, at Graeme Hall (0.07 sq km). This is largely surrounded by 
urban developinent. 

British Virgin Islands have mangroves scattered throughout the islands, mostly as scrubby fringe communities 
with the largest single area being some 3.4 sq km on the eastern end of Anegada. Mangroves have been declared 
a "critical natural resource" by the government and some areas are protected under conservation and planning 
legislation. 

Dominica has very restricted mangrove development, probably due to the steeply shelving coast. 
Grenada and the Grenadines have a number of small, mostly shrubby mangrove communities, but at the 
largest site on Grenada, Levera Pond (0.33 sq km), trees have a mean height of 15 m. 

Guadeloupe has extensive mangroves (61 sq km) in the Grand Cul de Sac Marin and the narrow channel 
between Grand-Terre and Basse-Terre. These partly fall within protected areas. Smaller mangrove communities 
are found in the various bays and estuaries of both islands. 

Martinique has a large area of mangrove swamps along the Baie de Fort-de-France. Smaller mangrove areas 
occur in the sheltered bays along the south and east coasts of the island. 

Montserrat has poorly developed mangroves due to the steeply shelving shores. Fox's Bay (0.02 sq km) is the 
only significant site and is a bird sanctuary. 

Netherlands Antilles (wdnd'ward group) have fringe mangroves in parts of the Simpson Bay Lagoon on 
St Martin, although most have been destroyed by extensive tourism developments. Mangroves are not found 
on Saba or St Eustatius. (See Aruba for leeward group.) 

St Kitts and Nevis have a few small mangrove sites, as basin communities on St Kitts and estuarine 
communities on Nevis. The largest site is Greatheeds (0.22 sq km), on St Kitts. It is largely scrubby but has five 
mangrove species. Some sites are protected. 

St Lucia has a number of well-developed mangrove areas, notably estuarine and basin formations. These are 
not threatened although there is soine charcoal production. Stands oi Rhizophora mangle have a mean height of 
23 m at Esperance Harbour. In recognition of their importance for fisheries, most of the larger sites have been 
protected as Marine Reserves. 

St Martin and St Barthelemy are administered with Guadeloupe. St Martin shares the Grand Etang de 
Simpsonbaai (Simpson Bay Lagoon) with the Dutch half of the island. Mangroves are found in a number of 
small lagoons to the north and east. The eastern part of St Barthelemy has well-developed fringing and lagoon 
mangrove areas. 

St Vincent and the Grenadines have scattered mangrove communities throughout the islands, mostly small 
and scrubby. In a number of areas they are threatened by sohd waste disposal and land reclamation. 
US Virgin Islands have mangrove sites scattered throughout the islands, with the largest sites being found on 
St Croix. These are mostly associated with saline ponds and lagoons. Some sites are threatened by urban 
development, dumping and landfill. The Virgin Islands National Park on St John includes some mangrove areas. 



110 World Mangrove Atlas 

Anguilla 

Land area 1 55 sq km 

Population (1992) 8,960 

Alternative estimate of mangrove area (Bacon, 1993b) 0.9 sq km 

Area of mangrove on the map 5 17sqkm# 

Number of protected areas with mangrove 

Map reference 

ECNAMP * 

Antigua and Barbuda 

Land area 440 sq km 

Population (1995) 68,000 

Alternative estimate of mangrove area (Bacon, 1993b) (49 sq km)t 

Area of mangrove on the map 1 3, 1 6 sq km# 

Number of protected areas with mangrove 
"f Figure includes salt ponds 

Map reference 

CCA (1991). Antij;ua and Barhtida: Country Environmental Profile. Caribbean Conservation Association, 
St Michael, Barbados. 212 pp. 

Barbados 

Land area 430 sq km 

Population (1995) 261,000 

GNP(1992) 6,530 US$ per capita 

Alternative estimate of mangrove area (Bacon, 1993b) 07 sq km# 

Area of mangrove on the map 0.30 sq km 

Number of protected areas with mangrove 1 

Map reference 

ECNAMP * 

British Virgin Islands 

Land area 130sqkm 

Population (1991) 16,749 

6NP ( 1 989) 1 0,000 US$ per capita 

Area of mangrove on the map 4.35 sq km# 

Number of protected areas with mangrove 1 

Map reference 

ECNAMP * 

Dominica 

Land area 750 sq km 

Population (1995) 71,000 

GNP(1992) 1,040 US$ per capita 

Area of mangrove on the map 1 .56 sq km# 

Number of protected areas with mangrove 7 

Map reference 

ECNAMP * 



The Americas 7JJ 

Grenada 

Land area 340 sq km 

Population (1995) 92,000 

GNP(1992) 2,310 US$ per capita 

Mean annual temperature 24°C 

Mean annual rainfall (coastal areas) 1,500 mm 

Alternative estimate of mangrove area (Bacon, 1993b) 2.35 sq km# 

Area of mangrove on the map 5.36 sq km 

Number of protected areas with mangrove 

Map reference 

ECNAMP * 

Guadeloupe (including St Martin and St Barthelemy) 

Land area 1,705 sq km 

Population (1990) 378,178 

Average monthly temperature range 23-27°C 

Mean annual rainfall 1,814 mm 

Area of mangrove on the map 39.83 sq km# 

Number of protected areas with mangrove 1 

Map reference 

St Martin and Barthelemy data taken from ECNAMP *, Guadeloupe from CNRS (1980). 
CNRS (1980). La Guadeloupe, Vegetation. Planche 9, Atlas des Departements d'Outre-Mer. 1:150,000. 
Centre d'Etudes de Geographie Tropicale, C.N.R.S. 33405 Talence, France. 

Martinique 

Land area 1,079 sq km 

Population (1990) 359,572 

Area of mangrove on the map 15.87 sq km# 

Number of protected areas with mangrove 3 

Map reference 

IGN (n.d.). Martinique. Carte 511, 1:100,000. Institut Geographique National, Paris, France. 

Montserrat 

Land area 106sqkm 

Population (1985) 11,852 

GNP(1985) 3,127 US$ per capita 

Average monthly temperature range 24-27°C 

Mean annual rainfall 1 ,628 mm 

Alternative estimate of mangrove area (Bacon, 1993b) 0.02 sq km# 

Area of mangrove on the map 31 sq km 

Number of protected areas with mangrove 1 

Map reference 

ECNAMP * 

Netherlands Antilles (windward group) 



Land area 68 sq km 

Population (1991) 36,356 

Area of mangrove on the map 0.87 sq km 

Number of protected areas with mangrove 



Map reference 

ECNAMP * 



1 12 World Mangrove Adas 

St Kitts and Nevis 

Land area 360 sq km 

Population (1995) 41,000 

GNP(1992) 4,670 US$ per capita 

Alternative estimate of mangrove area (Bacon, 1993b) 71 sq km# 

Area of mangrove on the map 0.43 sq km 

Number of protected areas with mangrove 

Map reference 

ECNAMP * 

St Lucia 

Land area 610 sq km 

Population (1995) ~ 142,000 

GNP(1992) 2,910 US$ per capita 

Alternative estimate of mangrove area (Bacon, 1993b) 1 54 sq km 

Area of mangrove on the map 1 25 sq km# 

Number of protected areas with mangrove 12 

Map reference 

OAS (1984). Saint Lucia - Land Use and Vc\^elation, 1:50,000. Prepared by the Department of Regional Development, of the 
Organisation of American States, with the collaboration of the Mimstry of Agriculture, Lands, Fisheries, Co-operatives 
and Labour, of the Government of Saint Lucia. 

St Vincent and the Grenadines 

Land area 390 sq km 

Population (1995) 112,000 

GNP(1992) 1,990 US$ per capita 

Alternative estimate of mangrove area (Bacon, 1993b) 0.45 sq km# 

Area of mangrove on the map 1 .54 sq km 

Number of protected areas with mangrove 2 



Map reference 

ECNAMP * 

US Virgin Islands 



Land area 353 sq km 

Population (1995) 101,809 

GNP(1990) 8,71 7 US$ per capita 

Alternative estimate of mangrove area (Bacon, 1993b) 9.78 sq km# 

Area of mangrove on the map 1 .06 sq km 

Number of protected areas with mangrove 1 

Map reference 

Berndtson and Berndtson (n.d.). Virgin Islands: US and British. 1:80,000. Berndtson and Berndtson Pubhcarions, 
Fiirstenfeldbruck, Germany. 

* ECNAMP - Data for a number of the smaller Caribbean islands have been prepared from a series o{ Preliminary Data 
Atlases pubhshed in 1980 by the Eastern Caribbean Natural Area Management Program, a co-operative effort of the 
Caribbean Conservation Association and the School of Natural Resources, University of Michigan. Data for these atlases 
have been drawn from a wide range of sources, in most cases the scale of the maps is between 1:50,000 and 1:300,000. 



The Americas i'13 

Mexico Map 7.1 

Land area 1,958,200 sq km 

Total forest extent ( 1 990) 485,860 sq km 

Population (1995) 93,670,000 

GNP{1992) 3,470 US$ per capita 

Mean monthly temperature range (Mazatlan, Pacific coast) 19-28°C 

Mean monthly temperature range (Menda, Yucatan) 22-28°C 

Mean annual rainfall (Mazatlan) 828 mm 

Mean annual rainfall (Menda) ' 957 mm 

Alternative estimate of mangrove area (SARH, 1992) 5,315 sq km# 

Area of mangrove on the map 9,328 sq km 

Number of protected areas vuith mangrove 12 

Mangroves are being lost very rapidly in Mexico. Estimated cover in the 1970s was 15,000 sq km and it may 
now be as low as 5,000 sq km, mainly as a result of clearance for agriculture, mariculture and urban development. 
Mangroves are also being increasingly used for firewood in coastal areas. The largest and best developed mangrove 
areas are associated with lagoons in the south and east of the country. These include the Asta and Pom Lagoons 
in Campeche, along the northern coast of the Yucatan Peninsula; and the delta of the Usumascinta River and 
the Laguna de Terminos in the southern Gulf of Mexico. On the Pacific coast, there are mangrove communities 
in the lagoons along the coast to the border with Guatemala. There are also important mangrove areas much 
further north, associated with the Agua Brava and Teacapan Lagoons. In the humid areas of the southeast, tree 
height reaches 30 m and mangrove communities may extend inland for several kilometres. With increasing 
latitude, ecosystem complexity decreases and dwarf or shrubby communities are widespread. The mangrove 
coverage on the map is from a recent but relatively low resolution source which could account for the difference 
in area between the map and the alternative reference. 

Map reference 

Digital mangrove data were kindly provided by Conservation International and are part of the map coverage for 
CI/NAWCC/USFWS/SEDESOL (1992). 

CI/NAWCC/USFWS/SEDESOL (1992). Humeddes de Mexico. 1:3,800,000. Conservation International, North American 
Wedands Conservation Council, US Fish and Wildlife Service and SEDESOL (Secretaria de DesarroUo Social). 

Nicaragua Map 7.2 

Land area 1 30,000 sq km 

Total forest extent ( 1 990) 60, 1 30 sq km 

Population (1995) 4,433,000 

GNP(1992) 410 US$ per capita 

Mean annual temperature (Pacific) 27°C 

Average annual rainfall range (Pacific) 1,500-1,700 mm 

Spnng tidal amplitude (Pacific) 3.3 m 

Alternative estimate of mangrove area (Polania and Mainardi, 1993) 1,550 sq km 

Area of mangrove on the map 1 ,7 1 8 sq km# 

Number of protected areas with mangrove 3 

The mangroves of Nicaragua are found along some 30% of the coast, and are approximately equally distributed 
between the Pacific and Caribbean coasts. They are best developed at the northern end of the Pacific coast, 
particularly on the Golfo de Fonesca (Estero Real), bordering El Salvador and Honduras. They are distributed 
right along the Caribbean coast and are associated with deltas and lagoons. These communities tend to be less 
degraded than those on the Pacific coast. There is widespread use of mangroves for fijelwood, which is a major 
energy source for many people, including a large proportion of the populations of some coastal towns and cities. 
It has been calculated that legal extraction of fuelwood is 9,000 in' per year, with between 4,000 and 7,000 m' 
per year for timber posts and a further 5,000 m' per year for other timber uses. Extraction without a permit is 
hkely to be considerably greater. Mangrove bark is important for tannin production, while the extraction of 
crabs, shrimps and molluscs is also economically important. Shriinp farming and the conversion of mangrove 
areas to other uses is not yet a major problem. Legislation to restrict the cutting of mangroves for timber is in 
place, although difficult to enforce. Projects are underway with international agencies to develop plans for the 
integrated management and sustainable use of the mangrove resources, particularly along the Pacific coast. 



114 World Mangrove Atlas 

Map reference 

Mangroves prepared from INRNA (1991), which plots all mangroves on the Pacific coast as 'Bosque daro sempervirente de 
mani^larcs y ticrras pantanosas de mannlarcs sin vci^etacion arborescente', effectively degraded mangrove. 

INRNA (1 99 1) . Estado Actual de la Ve^^etacion Forestal de Nicarai^ua. 1 : 1 ,000,000. Institute Nicaraguense de Recursos Naturales 
y del Ambiente, Direccion de Adimmstracion de Bosques Nacionales. 

Panama Map 7.6 

Land area 77,080 sq km 

Total forest extent { 1 990) 3 1 , 1 70 sq knn 

Population (1995) 2,659,000 

GNP(1992) 2,440 US$ per capita 

Mean monthly temperature range IdlTC 

Average rainfall range 1 ,000-7,000 mm 

Spring tidal amplitude (Pacific) 6 m 

Spring tidal amplitude (Canbbean) 5 m 

Alternative estimate of mangrove area (see map reference) 1 ,708 sq km 

Area of mangrove on the map 1,814 sq km# 

Number of protected areas with mangrove 5 

In Panama, mangroves are found along both coasts, but are most heavily developed on the Pacific coast, 
particularly the Gulfs of San Miguel and Chiriqui, both of which have nearly 500 sq km of mangroves. These 
forests are structurally well developed with stands of Rhizophora reaching 30-40 m in height and making up 
the dominant species over wide areas, with other species making more mixed communities along the salinity 
gradients in rivers and estuaries. The total coverage for the Caribbean coast is 60 sq km, most of which is 
concentrated in the Bocas del Toro region near the Costa Rican border. The Caribbean mangroves are generally 
not well developed, with trees less than 5 m in height. Rainfall is highly varied across the country, reaching 
6,000 mm per annum in the Bocas del Toro mangrove areas, but more typically 2,000 to 4,000 mm per annum 
in most coastal areas. Mangrove areas are used for the gathering of penaeid shrimp seed to supply numerous 
small shrimp farms along the Pacific coast. They are also of considerable importance in the hfe cycles of most 
shrimp and a number of finfish species that are important in commercial catch fisheries. On land, mangroves 
are exploited for timber, fuelwood and charcoal and there is a small tannin extracting industry. These uses are 
not causing widespread loss of mangrove areas. Some areas have been converted for agriculture, cattle grazing 
and urban development with these losses being most significant along the Gulf of Chiriqui. An oil spill severely 
affected mangroves along some 27 km of coast in 1986 and oil is considered a major potential threat to other 
areas, based on the large quantity transported (70 milUon tons) through the Panama Canal each year. There has 
been little or no legislation or management policy developed for the protection and development of mangrove 
resources. Although the available maps and area calculations are recent and accurate there is some confiision 
over the definition of mangrove that was used. In a recent study Duke ct al. (1993) have found these estimates 
to underestimate considerably the total area of mangroves and it has been suggested (Duke, pers. comm., 1995) 
that the maps may have only considered Rhizophora distribution. 

Map reference 

Institute Geografico Nacional 'Tommy Guardia' (1988). Republica de Panama - Inventario de Manglares. 1: 250,000. Five 
sheets. Institute Geografico Nacional 'Tommy Guardia', Panama. 

Peru Map 7.6 

Land area 1,285,220 sq km 

Total forest extent ( 1 990) 679,060 sq km 

Population (1995) 23,854,000 

GNP(1992) 950 US$ per capita 

Mean monthly temperature range 18-30°C 

Average rainfall range 100-300 mm 

Spring tidal amplitude 4 m 
Alternative estimate of mangrove area (Echevarria and Sarabia, 1993) 48 sq km 

Area of mangrove on the map 51 sq km# 

Number of protected areas with mangrove 1 

In Peru, mangroves are found in two distinct areas: a large area extending from the Ecuadorian border to the 
Rio Tumbes, and a much smaller area on the Piura River (approximately 3 sq km). The latter site is the 



The Americas US 

southernmost site for mangroves on the Pacific and is restricted to one species, /IWccMMia^ermmani. The chmate 
is semi-arid, but is highly variable from one year to another, and greatly affected by El Nino events which result 
in the displacement of the intertropical convergence zone and greatly increased rainfall, which can be 10 to 60 
times higher than average in some years. SaHnity levels are quite variable, but can be high (33 %o) during the 
summer period of January to March. The coasthne at Tumbes is highly dynamic and is affected by patterns of 
tidal flow, coastal currents and the sediment load carried by the river. This can lead to varying processes of 
accretion or deposition in different years. Traditionally, mangroves have been used for flielwood, charcoal, timber 
and poles. Recently, shrimp mariculture has expanded, causing reduction in the total area of mangrove by some 
12.5 sq km between 1982 and 1992, though there had been a considerable area removed before this time. 
Shrimp farming now occupies 70 sq km, of which 27 sq km are no longer working. Large numbers of people 
work on these farms catching shrimp larvae to export to Ecuador. This industry has led to the considerable 
expansion of the city of Tumbes, which has doubled in size since 1 96 1 . A threat to the mangroves and, indeed, 
to the human population in the area is likely to arise from a dam and irrigation scheme in the watershed of 
the Puyango-Tumbes Rivers. Mercury pollution from gold mining upstream, together with locally based urban 
and industrial pollution, may also affect the mangroves. There has been some natural regeneration of mangroves 
in a few areas, and in 1980 the Santuario Nacional los Manglares de Tumbes, covering some 29.72 sq km, was 
declared. A detailed GIS has been prepared of the mangroves in this area (see map references). 

Map references 

Unpublished maps (ONERN/ODC/FPCN, 1992) were kindly provided by Jorge Echevarria, Universidad Nacional de 
Tumbes. These cover the largest area of mangroves in Peru. Sources for these data come from 1:25,000 'carta 
fotogrametnca' and HRV SPOT imagery from 30 March 1991. A second, smaller, area on the Piura River (estimated at 
300 ha, J Echevama, pers. comm., 1995) has been added from a sketch map taken from Pefia and Vasquez (1985). 

ONERN/ODC/FPCN (\992). Mapa de cobertum y uso de la lierra (Ano 1992). Oficina Nacional de Evaluacion de Recursos 
Naturales (ONERN), Oficina de Coordinacion del Progama de Desarollo Forestal Peru-Canada (ODC) and Fundacion 
Peruana para la Conservacion de la Naturaleza (FPCN). 

Pefia, G.M. and Vasquez, P. (1985). Un ReUcto de Manglar en San Pedro (Piura). Bolctin de Lima 42: 1-7. 

Puerto Rico Map 7.4 

Land area 8,900 sq km 

Population (1995) 3,691,000 

GNP(1992) 6,580 US$ per capita 

Mean monthly temperature range 26-28°C 

Average rainfall range 1,000-5,000 mm 

Alternative estimate of mangrove area (Martinez etai, 1979) <60 sq km 

Area of mangrove on the map 92 <;q km# 

Number of protected areas with mangrove 9 

In Puerto Rico, mangroves are distributed on all coasts. The south coast, which is slightly drier, has mostly fringe 
and overwash communities with some scrubby basin communities, while the north coast has some riverine 
and basin communities. The largest single area is on the northeast coast around TorreciUa, which is a complex 
of estuarine and lagoon communities. By the late 1970s over 75% of Puerto Rico's mangroves had been 
destroyed. There was legal encouragement for this action as a means of reducing the numbers of malarial 
mosquitoes. Wide areas have been drained or filled and used for agriculture or urban development, while the 
major estuary of San Juan and large parts of the Jobos Bay have been developed as harbour faciuties. Human 
activity continues to threaten mangroves both directly through cutting or reclamation and through pollution, 
despite the recognised importance of mangroves in commercial fisheries. Part of the Jobos Bay was declared a 
national estuarine research reserve in 1987. In the 1980s the total area of mangroves increased considerably, the 
changes being the result of increased legal protection, the reversion of agricultural land to its original state, and 
the colonisation of new areas. 

Map reference 

Mangrove areas were copied onto a 1:500,000 base map from a series of eight maps contained in UNDC (1978). 
Subsequent to this work a more recent sketch map (Martinez, 1994) was made available. The mangrove distribution on 
this map is similar to that already prepared, but was used to add a coverage for Isla de Vieques. 

UNDC (1978). Puerto Rico Coastal Management Program and Final Environmental Impact Statement. Office of Coastal Zone 
Management, National Oceanic and Atmospheric Administration, US Department of Commerce. 



116 World Manj^rove Atlas 

Surinam Map 7.5 

Land area 1 63,270 sq km 

Total forest extent ( 1 990) 1 47, 680 sq km 

Population (1995) 463,000 

GNP(1992) 3,690 US$ per capita 

Average temperature 27°C 

Mean annual rainfall 2,200 mm 

Alternative estimate of mangrove area (SPS, 1 988) 1 , 1 50 sq km# 
Area of mangrove on the map ' 1 ,097 sq km 

Number of protected areas with mangrove 4 

The coast of Surinam, like that of Guyana and French Guiana, is low-lying and geologically very young. It 
receives riverine deposits from the Amazon in the east, the Orinoco in the west and the numerous rivers in 
between. Frmge mangroves are found along most of the coast, typically fronted by wide mudflats. Estuarine 
mangroves are also well developed. Inland from the frmge mangroves there are, typically, swamp or lagoon 
systems varying from fresh to hypersaUne, with both swamp forest and grasslands. Large parts of these systems 
dry out during the long dry season from September to November. The beaches are extremely important for 
nesting sea turtles, and the wider coastal ecosystems for enormous numbers of seabirds. It is the most important 
wintering area for north American and arctic shorebirds within South America. Surinam has a very low 
population density. The majority of people hve in the coastal zone, but as most of these are living in the capital, 
Paramaribo, there is relatively litde human pressure on most of the mangrove areas. Small areas of mangroves 
have been cleared for rice cultivation, and there is some contamination by pesticides. Some mangrove areas are 
protected, including the 120 sq km Coppename Monding and the 360 sq km Wia-wia nature reserve. The 
683 sq km Bigi Pan area is a multiple-use management area. Further areas have also been proposed for 
protection. 

Map reference ' 

The source map is largely based on 1978 data. 

SPS (1 988). Surm(!mcP/(iH(rt(/iij.StichtingPlanbureauSuriname. Department of Regional Development, O.A.S., Washington 
DC, USA. 

Trinidad and Tobago Map 7.5 

Land area 5,130 sq km 

Total forest extent (1990) 1,550 sq km 

Population (1995) 1,305,000 

GNP(1992) 3,950 US$ per capita 

Average temperature 26°C 

Mean annual rainfall 1,556 mm 

Alternative estimate of mangrove area (Bacon, 1993b) >70 sq km# 

Area of mangrove on the map 54 sq km 

Number of protected areas with mangrove 4 

Trinidad and Tobago have mangroves on all shores. They are best developed in estuaries on Trinidad, with the 
most important single area being the 37 sq km Caroni Swamp on the west coast. Lagoon and coastal fringe 
mangrove communities are also found, although estuarine swamps are the best developed, with trees Teaching 
23 m high. In most areas, the landward side of mangrove areas is backed by agriculture, although the Nariva 
Swamp inangroves form part of a much larger wetland system. Conversion to cultivation has led to the loss of 
wide areas of mangrove. Current uses of mangroves include a small amount of timber and charcoal extraction 
and direct-catch fisheries products including crabs, oysters and shrimps. Offshore fisheries close to mangrove 
areas are also important. The Caroni swamp, which is a tourist attraction, is home to the national bird, the scarlet 
ibis Eudocimus ruber. Although the site is protected, it suffers from industrial and agricultural pollution. 

Map reference 

Data are for Trinidad only, no data were found for Tobago. 

Institutional Consultants (International) Ltd. (1980). Inventory of the Indigettous Forest of Trinidad - Forest Resource Inventory 
and Management Section. 1:150,000. Prepared for the Goverrunent by Institutional Consultants (International) Ltd. in 
co-operation with the Forestry Division Ministry of Agriculture, Lands and Fisheries and the Canadian International 
Development Agency (CIDA). 



The Americas 117 

Turks and Caicos Map 7.3 

Land area 430 sq km 

Population (1990) 11,696 

Average monthly temperature range 24-28°C 

Mean annual rainfall 725 mm 

Alternative estimate of mangrove area (Bacon, 1993b) 236 sq km 

Area of mangrove on tfie map 1 11 sq km# 

Number of protected areas with mangrove 3 

The Turks and Caicos are a small group of low-lying islands which form the southernmost part of the Bahamas 
group. They are separated into the Turks Islands, lying on a small marine bank, and the Caicos Islands lying on 
the very large, shallow Caicos Bank. The latter islands have a very large area of mangrove, particularly 
concentrated in the southern portions of North, Middle and East Caicos Islands. For the most part mangroves 
are relatively scrubby or dwarf, with the tallest stands on Parrot Cay reaching 10 m in height. Mangrove 
communities are predominantly fringe, basin, lagoon and/or linked to salinas. The scrubby nature of the 
mangroves can be linked to the high salinities, which has been measured as 38%o in the sea and up to 84%o in 
the Salinas. Mangroves have historically been used for poles, charcoal and salt manufacture. These activities have 
decreased and mangroves are recolonising many salinas. Other mangrove areas are being cleared for resort and 
urban development, but most areas are not threatened. A large proportion of the mangroves on North, Middle 
and East Caicos Islands have been protected as wetlands of international significance. 

Map reference 

D.O.S. (1984). Turks and Caicos Islands. 1:200,000. Series: D.O.S. 609 Ed.2. Directorate of Overseas Surveys, UK. 

United States of America Maps 7.1 and 7.3 

Land area 9,372,610 sq km 

Land area (Florida) 139,697 sq km 

Total forest extent (1990) 2,095,730 sq km 

Population (1995) 263,138,000 

Population (Flonda) (1993) 13,642,540 

GNP(1992) 23,1 50 US$ per capita 

Mean monthly temperature range (Miami) 19-28°C 

Mean annual rainfall (Miami) 1,516 mm 

Spring tidal amplitude 1 m 

Alternative estimate of mangrove area No information 

Area of mangrove on the map (Florida only) 1,990 sq km# 

Number of protected areas with mangrove 48 

In the United States of America, mangroves are largely concentrated in the southern parts of Florida and form 
a major vegetation type in the southern three counties of that state. They show their greatest structural 
development in the southwest region where there are wide areas of low-lying sediments and there is considerable 
freshwater input from the Florida Everglades, delivering nutrients and moderating coastal salinity regimes. 
Although mangroves occur further north, their distribution is restricted by cold winter temperatures. There are 
isolated occurrences o( Avicetinia (lerininans in Texas, and at several locations marginal to the Mississippi deltaic 
plain in Louisiana, including the Chandeleur Islands (30°02'N). Hurricanes are a major chmatic feature in 
southern Florida and these can have devastating effects on mangrove communities. The most recent event was 
in 1992 and there is an average return time of 20 years, which means that hurricanes can limit the development 
of mangroves in most areas. Human induced stresses have been considerable in southern Florida, including 
drainage for agriculture, reclamation for urban development and alterations to the salinity regime, most notably 
caused by the development of a railway along the Florida Keys (now dismantled). Estimated losses range from 
44% in Tampa Bay to 82% in Biscayne Bay, south of Miami, and these losses were reported to have resulted in 
a 20% dechne in commercial fisheries. Research connecting mangroves to fisheries yields, combined with a 
growing environmental movement, led to a great reduction in rates of mangrove loss in the 1970s and 1980s. 
Strict laws were enacted for the protection of mangroves. Where destruction is permitted there are now typically 
complex mitigation procedures, including, in a number of cases, funding for major restoration or rehabilitation 
projects in other areas. Large areas of mangrove fall within the complex of protected areas which make up much 
of the land and sea area of southern Florida, notably the Florida Everglades National Park. 



118 World Mangrove Alias 

Map reference 

Data were generously provided by the Florida Marine Research Institute in digital format (FMRI, 1995). These are based 
on data gathered in the National Wetlands Inventory and are based on aerial photographs taken between 1984 and 1986 
which were transferred and rectified to the US Geological Survey 1 :24,000 quads. 

FMRI (1995). South Florida (Sanibcl Island to Biscayne Bay). 1:40,000. Digital dataset compiled by the Florida Marine 
Research Institute from various sources. 



Venezuela Maps 7.5 and 7.6 

Land area 912,050 sq km 

Total forest extent (1990) 456,900 sq km 

Population (1995) 21.483,000 

GNP(1992) 940 US$ per capita 

Mean monthly temperature range (Orinoco) 25-27°C 

Mean monthly temperature range (Cocinetas Lagoon) 27-31°C 

Average monthly rainfall range (Orinoco) 99-330 mm 

Average monthly rainfall range (Cocinetas Lagoon) 85-277 mm 

Alternative estimate of mangrove area (Conde and Alarcon, 1993a) 2,500 sq km# 

Area of mangrove on the map (5,302 sq km) 

Number of protected areas with mangrove 10 

Mangroves have a long history of use by man in Venezuela: archaeological sites within mangrove areas date back 
as far as 5,000 to 6,000 years. In recent years the mangroves have been extensively studied in many areas. The 
largest areas of mangroves are those associated with the Orinoco Delta, the San Juan River and the Gulf of 
Paria, in the far east of the country. The total area of mangrove in this region occupies over 1 ,300 sq km. These 
mangroves are well developed with trees reaching from 25 in to 40 m. To the west of these areas, most of the 
coast is arid or semi-arid and mangroves are less well developed, with trees rarely reaching heights of 20 m. 
Other key areas to the west include Tacangua Lagoon, Morrocoy Bay and a number of sites in the Maracaibo 
system in the far west. The latter area has three distinct bodies of water: the marine Gulf of Venezuela, the 
estuarine waters of the Maracaibo Strait and the limnetic waters of the Lago de Maracaibo, the latter with 
typical salinities in the range of 6 to 10%o. Distinct mangrove systems are associated with each of these. Both 
artisanal and commercial fisheries are important, with commercial fisheries being particularly so in Maracaibo, 
ofFTacarigua Lagoon, and in the Orinoco Delta. Threats to mangroves include indiscriminate use for timber 
and fuelwood, oil pollution, urban and tourism development and reclamation for agriculture. Expansion of salt 
pans and shrimp farms could represent a threat in the future. Actual quantification of mangrove losses is not 
possible, but concern to reduce these losses is increasing and a number of sites, totalling over 500 sq km, now 
fall within legally protected areas, while mangroves generally are also protected, and authorisation must be 
obtained for their utihsation. 

Major discrepancies exist between estimates of mangrove area in Venezuela. A number of authors have given 
figures close to 6,500 sq km, but it has been suggested that this is a gross over-estimate based on the 
misinterpretation of remote images, as the widespread tree Symphonia globulifera has similar spectral and structural 
characteristics to those of mangroves. It is not known whether there exist any maps which show this corrected 
distribution, if indeed it is correct. 

Map references 

Data were obtained from Huber and Alarcon (1988), which, although pubhshed in 1988, reflects the status of the vegetation 
cover in Venezuela for approximately 1982. Further reference was made to MARNR (1989) to improve this coverage. 
Huber, O. and Alarc6n, C. (1988). Mapa dc Vcgctacion dc Venezuela. 1:2,000,000. Ministerio del Ambiente y los Recursos 

Naturales Renovables and The Nature Conservancy. 
MARNR (1989). Manglares de Venezuela. Distribucion Ceograftca de los Manglares en Venezuela. Cuadernos, Lagoven, Caracas. 

Sources 

Alvarez, V. (1994). Los manglares de la Republica Dominicana. In: El Ecosistema de Manglar en America Latina y la Cuenca 
del Caribe: Su Manejo y Conservation. Suman.D.O. (Ed.). Rosenstiel School of Marine and Atmospheric Science, 
University of Miami, Miami, USA. pp. 209-217. 

Alvarez-Leon, R. (1993a). Mangrove ecosystems of Colombia; utilization, impacts, conservation and recuperation. In: 
Proceedings of a Workshop on Conservation and Sustainable Utilization oj Mangrove Forests in Latin America and Africa 
Regions. Lacerda, L.D. and Field, CD. (Eds). Mangrove Ecosystems Proceedings. International Society for Mangrove 
Ecosystems, Okinawa, Japan, pp. 9-10. 



The Americas i19 

Alvarez-Leon, R. (1993b). Mangrove ecosystems of Colombia. In: Comermtion and Sustainable Utilization of Mangrove 

Forests in Latin America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove Ecosystems Technical 

Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 75-1 13. 
Aragon de Rendon, B.B., Barrios, A.E. and Gamboa, L.M. (1994). Los Manglares de Guatemala. In: El Ecosistema de 

Manglar en America Latina y la Cuenca del Caribe: Su Manejo y Conservacion. Suman, D.O. (Ed.). Rosenstiel School of 

Marine and Atmospheric Science, University of Miami, Miaini, USA. pp. 125-132. 
Bacon, P. (1993a). Conservation and utilization of mangrove forests in Trimdad and Tobago and the Lesser Antilles. In: 

Proceedings of a Workshop on Conservation and Sustainable Utihzation of Mangrove Forests in Latin America and Africa 

Regions. Lacerda, L.D. and Field, CD. (Eds). Mangrove Ecosystems Proceedings. International Society for Mangrove 

Ecosystems, Okinawa, Japan, pp. 5-7. 
Bacon, P.R. (1993b). Mangroves in the Lesser Antilles, Jamaica and Trinidad and Tobago. In: Conservation and Sustainable 

Utihzation of Mangrove Forests in Latin America and Africa Regions Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove 

Ecosystems Technical Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 155-209. 
Bodero, A. (1993). Mangroves ecosystems of Ecuador. In: Conservation and Sustainable Utihzation of Mangrove Forests in 

Latin America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove Ecosystems Technical Reports. 

International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 155-209. 
Conde,J.E. and Alarcon, C. (1993a). Mangroves of Venezuela. In: Conservation and Sustainable Utilization of Mangrove 

Forests in Latin America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.) . Mangrove Ecosystems Techmcal 

Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. IW-lAli. 
Conde, J.E. and Alarcon, C. (1993b). The status of mangroves from the coast of Venezuela. In: Proceedings of a Workshop 

on Conservation and Sustainable Utilization of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and 

Field, CD. (Eds). Mangrove Ecosysteins Proceedings. International Society for Mangrove Ecosystems, Okinawa, 

Japan, pp. 9-10. 
D'Croz, L. (1993a). Mangrove uses and conservation in Panama. In: Proceedings of a Workshop on Conservation and 

Sustainable Utihzation of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, CD (Eds). 

Mangrove Ecosystems Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 8-9. 
D'Croz, L. (1993b). Status and uses of mangroves in the Repubhc of Panama. In: Conservation and Sustainable Utihzation 

of Mangrove Forests in Latin America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove 

Ecosystems Technical Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 115-127. 
Duke, N.C, Pinzon, Z.S. and Prada, M.C (1993). Inventory of mangrove forests in the vicinity of the Panama Canal. 

UnpubUshed report. Smithsonian Tropical Research Institute, Balboa, Panama. 
Echevarria,J. (1993). Mangrove ecosystems of Zarumilla-Tumbes, Peru Northern. In: Proceedings of a Workshop on 

Conservation and Sustainable Utihzation of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, 

CD. (Eds). Mangrove Ecosystems Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan. 

pp. 11-12. 
Echevarria,J. and Sarabia,J. (1993). Mangroves of Peru. In: Conservation and Sustainable Utilization of Mangrove Forests in 

Latin America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.) . Mangrove Ecosysteins Technical Reports. 

International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 43-53. 
Elhson,J. (1993). Mangroves of Bermuda and the Cayman Islands. In: Proceedings of a Workshop on Conservation and 

Sustainable Utihzation of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, CD. (Eds). 

Mangrove Ecosystems Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 2. 
Fromard, F., Mougin, E., Marty, G., Lopez, A., Prost, M.T., Lointier, M., Rudant.J.P. and Blasco, F. (1993). Structure et 

evolution des mangroves guyanaises: etudes in situ et par teledetection. JoHrnccs du Programme Environnement CNRS. 

ORSTOM, Lyon, 13-15 janvier. 
Funes, CA. (1994). Situacion de los bosques salados en El Salvador. In: El Ecosistema de Manglar en America Latina y la 

Cuenca del Caribe: Su Manejo y Conservacion. Suman, D.O. (Ed.). Rosenstiel School of Marine and Atmospheric 

Science, University of Miami, Miami, USA. pp. 1 15-124. 
Garcia, N.H. and Camacho, J.J. (1994). Informe sobre manglares de Nicaragua, America Central. In: El Ecosistema de 

Manglar en America Latina y la Cuenca del Caribe: Su Manejo y Conservacion. Suman, D.O. (Ed.). Rosenstiel School of 

Marine and Atmospheric Science, University of Miami, Miami, USA. pp. 160-167. 
GFC/CID. (1989). National Forestry Action Plan 1990-2000. Guyana Forestry Commission/Canadian International 

Development Agency, Georgetown, Guyana. 
Harcourt, CS. and Sayer, J.A. (1996). T7ic Conservation Atlas of Tropical Forests: the Americas. Simon and Schuster, 

New York, USA. 335 pp. 
Herz, R. (1991). Manguezais do Brasil. Instituto Oceanografico da Universidade de Sao Paulo, Sao Paulo, Brazil. 

Unpaginated. 
lUCN (1983). Global status of mangrove ecosystems. Commission on Ecology Papers No. 3. Saenger, P., Hegerl, EJ. and 

Davie, J.D.S. (Eds). International Union for Conservation of Nature and Natural Resources, Gland, Switzerland. 88 pp. 



120 World Mangrove Atlas 

Jimenez, J. A. (1993). Status of mangrove ecosytems in Central America. In: Proceedings of a Workshop on Conservation and 

Sustainable Utilization of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, CD. (Eds). 

Mangrove Ecosystems Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 7-8. 
Kjerfve, B. and Lacerda, L.D. (1993). Mangroves of Brazil. In: Conservation and Sustainable Utilization of Mangrove Forests 

in Latin America and Africa Regions Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove Ecosystems Technical Reports. 

International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 245-272. 
Lacerda, L.D. (1993). Conservation and Sustainable Utilization of Mangrove Forests in Latin America and Africa Regions Part I - 

Latin America. Mangrove Ecosystems Technical Reports. No 2. International Society for Mangrove Ecosystems, 

Okinawa, Japan. 272 pp. 
Lacerda, L.D. and Field, CD (1993). Proceedings of a Workshop on Conservation and Sustainable Utilization of Mangrove 

Forests in Latin America and Africa Regions. Mangrove Ecosystems Proceedings. International Society for Mangrove 

Ecosystems, Okinawa, Japan. 28 pp. 
Lescure,J.P. and Tostain, O. (1989). Les mangroves guyanaises. Bois et Forets dcs Tropiques, n" special Guyane, 220: 35-42. 
Lointier, M. (1986). Hydrodynamique et morphologie de I'estuaire du fleuve Sinnamary (Guyane franfaise). Colloque 

Sepanguy-Sepanritt. Cayenne, 27-29 avril 1985. pp. 37-44. 
Lot, A. and Novelo, A. (1990). Forested wedands of Mexico. In: Forested Wetlands. Lugo, A.E., Brinson, M. and Brown, S. 

(Eds). Ecosystems of the World. Elsevier, Amsterdam, The Netherlands, pp. 287-298. 
Lugo, A. E. and Snedaker, S.C (1974). The ecology of mangroves. Annual Review of Ecology and Systematics 5: 39-64. 
Martinez, R., Cintron, G. and Encarnacion, L.A. (1979). Mangroves in Puerto Rico: a structural inventory. Department of 

Natural Resources, San Juan, Puerto Rico. 
Martinez, R.F (1994). Status del manejo y reglamentacion de los manglares en Puerto Rico. In: El Ecosistema de Manglar 

en America Latina y la Cuenca del Caribe; Su Manejo y Conservacion. Suman, DO. (Ed.). Rosenstiel School of Marine 

and Atmospheric Science, University of Miaini, Miami, USA. pp. 194-208. 
Mougin, E., Lopes, A., Hery, R, Marty, G., Le Toan, T, Fromard, F and Rudant,J.P. (1993). Multifrequency and 

multipolarisation on mangrove forests of French Guyana during SAREX-92 experiment. Prelirmriary results. 

Workshop Proceedings Sarex 92, Dec. 1993, Pans ESA. pp. 193-203. 
ODA (1989). Belize Tropical Forestry Action Plan. Overseas Development Administration, London, UK. 
Olson, D. M., Dinerstein, E., Cintron, G. and lolster, P. (1996). A conservation assessment of mangrove ecosystems of 

Latin America and the Caribbean. Report from WWF's Conservation Assessment of Mangrove Ecosystems of Latin 

America and the Caribbean Workshop, December 2-4, 1995, Washington DC, USA. 
Oyuela, O (1994). Los manglares del Golfo de Fonesca - Honduras. In: El Ecosistema de Manglar en America Latina y la 

Cuerua del Caribe: Su Manejo y Conservacion. Suman, DO (Ed.). Rosenstiel School of Marine and Atmospheric 

Science, University of Miami, Miami, USA. pp. 133-143. 

Padron, CM. (1993). Status and management of mangroves of Cuba. In: Proceedings of a Workshop on Conservation and 
Sustainable Utilization of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, CD (Eds). 
Mangrove Ecosystems Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 4-5. 

Padron, CM., Llorente, S.O. and Menendez, L. (1993). Mangroves of Cuba. In: Conservation and Sustainable Utilization of 
Mangrove Forests in Latin America and Africa Regions Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove Ecosystems 
Technical Reports. Internationa] Society for-Mangrove Ecosystems, Okinawa, Japan, pp. 147-154. 

Polarua,J. (1993). Mangroves of Costa Rica. In: Conservation and Sustainable Utilization of Mangrove Forests in Latin 
America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove Ecosystems Technical Reports. 
International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 129-137. 

Polania,J. and Mainardi, V. (1993). Mangroves forests of Nicaragua. In: Conservation and Sustainable Utilization of 

Mangrove Forests in Latin America and Africa Regions. Part I - Latin America. Lacerda, L.D. (Ed.). Mangrove Ecosystems 
Technical Reports. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 139-145. 

Prost, M.T, Lointier, M. and Pannetier, G. (1989). L'envasement des cotes de Guyanes. Nature Guyanaijc,Sepanguy, 
Cayenne, pp. 25-32. 

SARH (1992). Mexico 1991-1992 - Inventario Nacional Forestal de Gran Vision: Reporte Principal. Secretaria de Agricultura 
y Recursos HidrauUcos, Subsecretaria Forestal, Mexico. 

Scott, DA. and Carbonell, M. (1986). A Directory of Neotropical Wetlands. lUCN and IWRB, Cambridge and Shmbridge, 
UK. 684 pp. 

Shaeffer-NoveUi, Y. (1993). Brazihan Mangroves. In: Proceedings of a Workshop on Conservation and Sustainable Utilization of 
Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, CD (Eds). Mangrove Ecosystems 
Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 12-13. 

SPS (1988). Suriname Plantatlas. Stichting Planbureau Suriname/Department of Regional Development, OAS, 
Washington, DC, USA. 

Suman, DO. (1994). El Ecosistema de Manglar en America Latina y la Cuenca del Caribe: Su Manejo y Conservacion. 
Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miaira, USA. 263 pp. 



Tlte Americas 121 

UNDC (1978). Puerto Rico Coaslal Management Program and Final Erwironment Impact Statement. Office of Coastal Zone 
Management, National Oceanic and Atmospheric Admimstration, US Department of Commerce. 

Yariez-Arancibia, A., Lara-Dominguez, A.L., Zapata, G.J.V., Arriaga, E.R. and Seijo,J.C. (1993). Mangroves ecosystems 
of Mexico: ecological function, economic value and sustamable development. In: Proceedings of a Workshop on 
Conservation and Sustainable Utilization of Mangrove Forests in Latin America and Africa Regions. Lacerda, L.D. and Field, 
CD. (Eds). Mangrove Ecosystems Proceedings. International Society for Mangrove Ecosystems, Okinawa, Japan, 
pp. 3-4. 

Zisinan, S.A. (1990). Mangrove habitats of Belize: extent, characteristics and research needs. Report to the Natural 
Resources Institute of the Overseas Development Administration for the Tropical Forestry Action Plan for BeUze. 



n2 



World Mangrove Atlas 




o 
u 

•a 
% 






The Americas 



123 







U4 



World Mangrove Atlas 




«« 
^ 



O 



73 

a 



n 



n 
T3 



_0 



K1 



Tlie Americas 



125 





1 


< 


( cno 


f , 




^ ■^-" ( 


o 


§ 


<^p^ ( 




< 

09 


(N 









1 






1 L- 






o 


f^ V V 






■^ 


232 








.^ " ^ 




< 

D 




Qy 


O 


/^ *^ m 












\ -C 
























^^4^ "" 


m 






w 




s 


--. o 


< 


^ O 


«^ 


't: 






T3 

8 

IS 

o 
u 



S 






126 



World Mangrove Atlas 




a 

a 
S3 
■3 
O 
« 
*•* 

a 
a 

7^ 
'a 

•a 
■3 



s 

N 
01 

a 
a 









Ttie Americas 



127 




500 km 

Caribbean 
Sea 



NETHERLANDS 
ANTILLES 

8A t\ c^Bonaire 



TO'V-W^.U^-W^J 



Map 7.6 Northwest South America 



128 



World Manj^roue Atlas 




Map 7.7 Brazil 



8 
West Africa 



Mangroves are found in all countries of West Africa from Mauritania in the north to Angola in the south. They 
are not found on the coast of Namibia or the west coast of South Africa. The mangroves of the region have 
been described by Hughes and Hughes (1992), Diop (1993) and Saenger and BeUan (1995). There are seven 
indigenous species of mangrove and one introduced species, Nypa fruticans on the Atlantic coast of Africa. All 
the indigenous species of mangrove on the Atlantic coast of Africa are shared with the Atlantic and Pacific coasts 
of America. The total area of mangroves in the region is some 27,995 sq km, representing some 16% of the 
total global area. Saenger and Bellan (1995) suggest that as a result of adverse sea level and climatic changes 
since the last significant geological transgression, the mangrove vegetation has contracted significandy in areal 
extent, with the remnants effectively confined to lagoons, embayments and deltas. 

The northern limit of the occurrence of mangroves is the He Tidra (19°50'N) in Mauritania, while the 
southern limit of extensive mangrove vegetation is the Angolan estuary ofthe Rio Longa (10° 18'S).The northern 
and southern limits of mangroves coincide with arid regions that are defined as areas having a yearly rainfall of 
less than 30 mm. It has been suggested (Saenger and Bellan, 1995) that mangrove distribution in western Africa 
IS more limited by aridity than by temperature. Much ofthe western coast of Africa is umfonnly mild to warm 
throughout the year but there is considerable variation in rainfall, with very high figures recorded in the coastal 
areas of Nigeria, Guinea, Guinea Bissau, Cameroon, Gabon and Zaire. In some places this can be in excess of 
4,000 mm per year. Elsewhere, in countries such as Cote d'lvoire, Ghana, Togo and Benin, the annual rainfall 
dechnes to between 1,000 and 2,000 mm per year and is broken by two short dry periods. Along the entire 
coastline of western Africa maximal rainfall generally coincides with the warmer months and, unlike many 
mangrove coasdines elsewhere, cyclone activity is absent. 

Mangrove forests occur on all the coasts from Mauritania to Angola, but the best developed are those with 
the heaviest rainfall, namely the coasts and river estuaries of Gambia, Guinea, Guinea Bissau, Gabon and Nigeria. 
The extent of mangroves is also determined by the presence of suitable habitats. In Nigeria, mangroves can be 
found up to 50 kin from the coast. Rivers are tidal for many kilometres in some countries, especially Senegal 
and Gambia, and in these places mangroves occur 1 60 km up river. 

The people ofthe coastal regions ofthe countries of West Africa depend on the mangroves for firewood and 
timber for construction. Locally, mangrove wood is used extensively in the production of salt. There is also 
extensive use of the mangrove habitat for fishing and sheUfish collection. Mangroves are threatened by over 
cutting, conversion of land for agricultural purposes and by pollution in areas where oil is being produced. 



130 



World Mangrove Atlas 



Table 8.1 Mangrove species list for West Africa 





1) 
o 

1 


o 

T3 

C 
fQ 

C 

'c 
m 


c 
o 
o 

i 

m 

u 


o 

3 


o 

T3 

B 
•o 

u 


OJ 

o 

to 
u 
cr 


c 
o 

-Q 


3 

E 




=3 


3 


1 


.2 

C 

tD 
2 


2 


1 

-a 

c 

1— 


to 
en 

s 


1 

ID 




Acrostichum aureum 


• 


• 


• 




• 




• 


• 


• 


• 




• 




• 


m 


• 




• 


Avicennia germinans 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


Conocarpus erectus 


• 


• 


• 




• 




• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


• 


Laguncularia racemosa 


• 


• 


• 




• 




• 


• 


• 


• 


• 






• 




• 


• 


• 


Nypa fruticans 






t 






















1 










Rhizophora harrisonii 


• 


• 


• 








• 


• 


• 


• 


• 


• 




• 


• 


• 


• 




Rhizophora mangle 


• 




• 








• 


• 




• 


• 






• 




• 


• 


• 


Rhizophora racemosa 


• 


• 


• 


• 




• 


• 


• 


• 


• 


• 


• 


• 


• 




• 


• 


• 



1 Introduced 








Country sources 








Angola 


Saenger and Bellan, 


1995 


Guinea 


Benin and Togo 


Saenger and Bellan, 


1995 


Guinea-Bissau 


Cameroon 


Saenger and Bellan, 


1995 


tiberia 


Congo 


Saenger and Bellan, 


1995 


Mauritania 


Cote d'lvoire 


Saenger and Bellan, 


1995 


Nigena 


Equatoral Guinea 


Saenger and Bellan, 


1995 


Sao Tome anc 


Gabon 


Saenger and Bellan, 


1995 


Senegal 


Gambia 


Saenger and Bellan, 


1995 


Sierra Leone 


Ghana 


Saenger and Bellan, 


1995 


Zaire 



Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 
Saenger and Bellan, 1995 



Angola 



Map 8.3 



Land area 1 ,246,700 sq km 

Total forest extent 52,950 sq km 

Population 8,500,000 

GNP 620 US$ per capita 

Mean monthly temperature range 20-26°C 

Mean annual rainfall 750 mm 

Spnng tidal amplitude (Luanda) 5-1 ,7 m 
Alternative estimate of mangrove area (Saenger and Bellan, 1995) 1,250 sq km# 

Area of mangrove on map 607 sq km 

Number of protected areas with mangrove 2 

In Angola, the mangrove flora is richest in the enclave of Cabinda but the number of species declines to the 
south. The coast becomes more arid to the south and inshore sea surface temperatures decline. An abrupt 
transition from a tropical to a temperate spectrum of species is seen in the vicinity of Cape Santa Maria. The 
most extensive stands of mangroves in Angola are found in the estuary of the Lubinda River, Cabinda and the 
estuary of the Zaire River, where they extend along the southern open coast. Other extensive mangrove 
communities occur at the mouths of the Chiluango, Bambongo, Longa and Cuanza Rivers. Rhizophora racemosa 
and R. mangle can reach heights of up to 30 m in north Angola but in the south they attain heights of less than 
a metre. In the south, Avicennia germinans also appears in stunted formations. A substantial proportion of the 
mangroves has either been cleared or severely disturbed by firewood collection. In Cabinda there has been some 
disturbance of the mangroves in the wake of oil exploration. 

Map reference 

Mangroves were annotated onto a 1:1,000,000 base map by R.H. Hughes, and are based on Hughes and Hughes (1992). 
Further mangroves were annotated by Fran<;ois Blasco for the Zaire estuary. 

Hughes, R.H. and Hughes, J.S. (1992). A Directory of African Wetlands. lUCN, Gland, Switzeriand and Cainbridge, 
UK/UNEP, Nairobi, Kenya/WCMC, Cambridge, UK. 820 pp. 



West Africa 131 

Benin and Togo Map 8.2 

In Benin, the mangroves are confined to brackish coastal lagoons as there are no active deltas and the shoreline 
is subject to significant wave action. The coastal lagoons occupy an area of 3,000 hectares and are subject to 
two rainy seasons and two dry seasons. There are six species of mangrove in Benin but Rhizophora mangle is 
absent and it has been suggested that this might be due to the irregular and hyposaline regime in the lagoon. 
Laguncularia and Rhizophora harrisonii are rare. In some parts of the lagoons mangroves can still be found reaching 
to heights of 22 m. The Benin Lagoon system extends into Togo and mangroves occur around the mouth of 
the Mono River and its western tributaries. The height of the trees rarely exceeds 10 m. There are only two 
species of mangrove found in Togo. The mangrove zone in Benin is densely populated by ethnic groups and 
the religious beliefs of these people often help preserve the mangrove. An important use of mangrove wood is 
for salt extraction and it has been estimated that one cubic metre of mangrove wood is required to produce 
one hundred kilograms of salt. In Togo, the use of mangroves appears to be less and at present there appears to 
be a balance between production and exploitation. The construction of a hydroelectric dam across the River 
Mono may affect mangroves in both Benin and Togo. 

Benin 

Land area 1 10,620 sq km 

Total forest extent 35,200 sq km 

Population 4,700,000 

GNP 340 US$ per capita 

Mean monthly temperature range 22-34°C 

Mean annual rainfall 1,307 mm 

Spring tidal height (Cotonou) 1.3 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 69 sq km 

Area of mangrove on map 1 7 sq km# 

Number of protected areas with mangrove 

Map reference 

Prepared from a series of eight maps from Baglo (1989), based on aerial photographs plotting the mangroves of the entire 
coast at a scale of c. 1:30,000. 

Baglo, M.A. (1989). La mangrove du Benin: grands equilibres ecologiques et perspecirves d'amenagement. PhD Thesis, 
Universite Paul Sabatier de Toulouse, France. 

Togo 

Land area 56 790 sq km 

Total forest extent (1990) 1 3,530 sq km 

Population (1995) 4,138,000 

GNP (1992) 390 US$ per capita 

Mean monthly temperature range 24-29°C 

Mean annual rainfall 850 mm 

Spring tidal amplitude 0.3-1 .7 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 26 sq km# 

Area of mangrove on the map No data 

Number of protected areas with mangrove 

Map reference 

No data 



132 World Mangrove Atlas 

Cameroon Map 8.3 

Land area 475,440 sq km 

Total forest extent (1990) 203,500 sq km 

Population (1995) 13,275,000 

GNP(1992) 820 U5$ per capita 

Mean monthly temperature range 21-31°C 

Mean annual rainfall 5,000 mm 

Spring tidal amplitude (Point Olga) 0.4-2,3 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 2,434 sq km 

Area of mangrove on the map 2,494 sq km# 

Number of protected areas with mangrove 1 

About 30% of the coastline of Cameroon is occupied by mangrove swamps. Two major areas of mangrove lie 
on the coast east and west of Mount Cameroon and these are characterised by seasonally high rainfall and river 
flow. It has been estimated that 145 billion cubic metres of fresh water annually pour into the Gulf of Guinea. 
Rhizophora racemosa makes up 90-95% of the mangrove area in the tidal zone and it can reach heights of up to 
25 m but is more often only 4-8 m in height fijrther inland. Recently, Nypa has become distributed throughout 
soine of the estuaries. The inangroves of Cameroon are relatively densely populated and are used for 
construction, food and medicinal purposes but over-exploitation is not marked, except for soine over-cutting. 
There is an important fishing industry present off the coast of Cameroon. Pollution poses something of a threat 
to the mangroves. It arises from the pesticides and fertilisers from the rubber, oil palm and banana coastal 
plantations leached into the mangroves and from offshore oil operations. 

Map reference 

Letouzey, R. (1985). Carte Phyto'^eo^^raphiquc du Camcrouti. 1:500,000 (mangroves on two sheets). Institut de la Carte 
Internationale de la Vegetation, Toulouse, France and the Institut de la Recherche Agrononiique (Herbier National), 
Yaounde, Cameroon. 

Congo Map 8.3 

Land area 342,000 sq km 

Total forest extent ( 1 990) 1 98,650 sq km 

Population (1995) 2,590,000 

GNP(1992) 1,030 US$ per capita 

Mean monthly temperature range 2 1 -27''C 

Mean annual rainfall 1,500 mm 

Spring tidal amplitude 0-4-1.3 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995} 120 sq km# 

Area of mangrove on the map 188sqkm 

Number of protected areas with mangrove 1 

There are relatively few mangrove forests in the Congo - most are restricted to coastal estuaries and lagoons - 
there are no mangroves on the sea-front. The best developed mangrove forests are located at Malonda and 
Conkouati Lagoons. The dominant mangrove is Rhizophora racemosa, though this becomes more scarce upstream 
and eventually the mangroves merge into freshwater palm-pandan swamps, backed by papyrus or freshwater 
swamp forest. Tidal influence can extend 10-30 km inland on several rivers. It has been suggested that a long 
dry season from June to September and the presence of a cold current not far off the Congolese coast may 
limit the developinent of mangroves. Oil exploration has occurred all along the coast of Congo and production 
occurs both onshore and offshore, as a consequence of which some coastal lagoons are polluted by petroleum 
waste. The mangroves are used by the coastal population for firewood and construction, but they are not 
over-exploited. 

Map reference 

Mangroves were annotated onto a 1:1,000,000 basemap by R.H. Hughes, and are based on Hughes and Hughes (1992). 

Hughes, R.H. and Hughes, J. S. (1992). A Directory of African Wetlands. lUCN, Gland, Switzerland and Cambridge, 
UK/UNEP, Nairobi, Kenya/WCMC, Cambridge, UK. 820 pp. 



West Africa J33 

Cote d'lvoire Map 8.2 

Land area 322,460 sq km 

Total forest extent ( 1 990) 1 09,040 sq km 

Population (1995) 14,401,000 

6NP(1992) 700 US$ per capita 

Mean monthly temperature range 24-27°C 

Mean annual rainfall 2,800 mm 

Spring tidal amplitude (Abidjan) 0-2-1 .2 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1 995) 1 50 sq km 

Area of mangrove on the map 644 sq km# 

Number of protected areas with mangrove 2 

In Cote d'lvoire, mangroves once occurred in most of the lagoons, river deltas and estuaries but many of the 
mangroves have been destroyed for firewood and urban development. Mangroves have also been disturbed by 
the construction of canals opening up the lagoons. There is very little variation in temperature along the coast 
and this means that any changes in the mangroves are hkely to be due to differences in soil, salinity and water 
movement characteristics. There are significant differences of rainfall along the coast. The mangroves of Cote 
d'lvoire can be divided into two main groups: the region between Assinie and Fresco, which is a series of 
lagoons into which rivers empty; and the region between Fresco and the border with Liberia at the CavaUy 
River, which is a series of deltaic river mouth systems. The lagoon mangroves are relatively small but can reach 
heights of around 20 m at Grand Bassam. The lagoon systems contain Rhizophora racemosa, Avkennia germinans 
and Conocarpus erectus, while the deltaic systems are dominated hy A. germinans and R. racemosa. R. racemosa occurs 
closest to the sea, followed by A.germinans, with C. erectus nearest the land. 

Map reference 

Map based on a 1 : 1,000,000 base map and more detailed sketch maps of specific sites contained in Egnankou Wadja (1985). 
Egnankou Wadja, M. (1985). Etude des mangroves de Cote d'lvoire: aspect ecologique et recherches sur les possibilites de 
leur ainenagement. PhD Thesis, Umversite Paul SabaOer de Toulouse, France. 

Equatorial Guinea Map 8.3 

Land area 28,050 sq km 

Total forest extent ( 1 990) 1 8,260 sq km 

Population (1995) 400,000 

GNP(1992) 330 US$ per capita 

Average temperature 26°C 

Mean annual rainfall 3,000 mm 

Spnng tidal amplitude 0.3-1.7 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 257 sq km 

Area of mangrove on the map 277 sq km# 

Number of protected areas with mangrove 

Equatorial Guinea is the only Spanish-speaking nation in sub-Saharan Africa and one of the least developed. 
Extensive development of mangroves is confined to three estuaries: Mbini, Muni and Ntein Rivers. The Muni 
estuary is the combination of several rivers and it is 2 km wide over much of its length. Mangroves extend from 
just inside the mouth to the head of the estuary, 17 km inland. There are about 65 sq km of tidal forest on the 
estuary dominated by Rhizophora racemosa and Avicennia germinans in the more seaward regions. There are a 
number of villages in the mangroves which have subsistence economies. The mangroves have suffered Utde 
degradation though there has been some cutting for firewood. 

Map reference 

No recent data were available. Source did not include data for Bioko or Annobon. 

Servicio Geografico del Ejercito (1960). Untided. 1:100,000, 15 sheets. Servicio Geografico del Ejercito. 



134 World Mangroi'e Atlas 

Gabon Map 8.3 

Land area 267,670 sq km 

Total forest extent (1990) 182,350 sq km 

Population (1995) 1,367,000 

GNP(1992) 4,480 U5$ per capita 

Mean monthly temperature range 23-30''C 

Mean annual rainfall 2,645 mm 

Spnng tidal amplitude (Libreville) 4-2 4 m 

Alternative estimate of mangrove area (Fromard and Pontes, 1994) 2,500 sq km# 

Area of mangrove on tfie map 1 ,759 sq km 

Number of protected areas with mangrove 1 

In Gabon, river mouths tend to be deflected northwards because of the prevailing currents and mangroves tend 
to develop in the folds where the rivers turn north. Mangrove forests occur in all estuaries, bays and lagoons 
along the coast and they are more extensive on the south banks than the northern banks. The main concentration 
of mangroves is at the mouths of the River Como, where Libreville is situated on the northern sand spit, and 
around the Ogooue River. Rhizophora racemosa, R. harrisotiii, R. mangle and Avicennia germinam dominate the 
seaward areas, while Acrostichum aureum, Conocarpus erectus and Lagimcularia racemosa are found in less inundated 
zones and in the dry fringes. The Rhizophora canopy can reach 30 m in height in the Bay of Cape Lopez. In 
Gabon an extensive freshwater swamp often appears to be associated with mangroves and this may have led to 
an over-estimation of the area of inangroves in the past. There does not appear to be much commercial 
exploitation of the inangroves. 

Map references 

High resolution data (1;150,000) were used where available from Pontes and Fromard (1993, 1994). Gaps in these 

coverages were filled from Maley (in press). Minor corrections were added by Francois Blasco. 

Pontes and Fromard (1993). Carte dc la vegetation Cap Lopez - Pointe Fetiche au 1:150,000. One sheet. ICIV, CNRS/UPS 

pour ELF Gabon. 
Pontes and Fromard (1994). Carte de la vegetation: Estuaire du Gabon; Nyonie; Gongue. Three sheets. ICIV, CNRS/UPS pour 

ELF Aquitaine, Toulouse, Prance. 
Maley, J. (1997). Histoire recente de la foret dense humide afncaine et essai sur le dynaimsme de quelques formations 

forestieres. In: Paysages quaternaires de I'Afrique Ccntrale Atlantique. Schwartz, D. and Lanfiranchi, R. (Eds). Travaux et 

Documents de I'ORSTOM, Paris, France. 



Gambia Map 8.1 

Land area 1 1,300 sq km 

Total forest extent ( 1 990) 970 sq km 

Population (1995) 980,000 

GNP(1992) 390 U5$ per capita 

Mean monthly temperature range 17-28°C 

Mean annual rainfall 925 mm 

Spring tidal amplitude (Banjul) 2-1 8 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 497 sq km# 

Area of mangrove on the map 747 sq km 

Number of protected areas with mangrove 5 

The country of Gambia forms an enclave within Senegal. It is essentially the valley of the navigable Gambia 
River and it extends 320 km inland from the coast. At the coast the country is about 45 km wide and this width 
decreases to some 10 km on either side of the river. An ahnost continuous belt of mangroves exists from the 
mouth of the river to about 1 60 km inland and it is the most pristine of the remaining natural habitats in the 
country. The mangrove and salt marsh species in Gambia are the same as those in Senegal. The height of the 
mangroves tends to increase after the first 25 km upstream and Rhizophora can attain heights of 20 m.The extent 
of the inangrove swamp tends to decrease in the lower parts of the river and is better developed at the mouths 
of small tributaries further upstream. 

Map reference 

This map (USGS, 1985) was kindly made available to WCMC by the EDC International Projects Department of the 
EROS Data Center, and was compiled from the interpretation of Landsat imagery of different dates and from extensive 
ground surveys. A considerable eastward extension of the mangrove coverage to Georgetown was made on the advice 
of Francois Blasco. This should be regarded as a crude approximation only. 

USGS (1985). Range and Forest Resources of Senegal. 1:1,000,000 scale. Digital map prepared for the US Agency for 
International Development (USAID) by the US Geological Survey, National Mapping Division, EROS Data Center. 



West Africa 



135 



Case study 



The mangroves of Gabon 

Several physiognomic and ecological facts have recently been recorded by Fromard and Pontes 
(1994). Despite very favourable physical and human parameters, the mangrove forests of Gabon, 
where all West African species are found, are not extensive. With the exception of the narrow 
riverine Rhizophora harrisonii belt, where growth and regeneration are good, other mangrove 
stands show poor or very poor development. An Avicennia belt is observed in many areas and 
seems to be restricted to the limits of the daily tidal influence. An inner belt of dwarf R. harrisonii 
is also observed (Plate 8.1). Growth seems limited by chemical or physical (or both) parameters of the 
soil (Figure 8.1). 

Deforestation is not a major threat in Gabon. The only major threat is from the oil extraction 
which is taking place in the mangrove areas and could potentially generate disastrous pollution. 

Figure 8.2 is an aerial photograph of the deltaic mangroves in the Cape Lopez Bay area which 
shows clearly the sort of detail available. It is quite possible to determine both the forest extent and 
elements of the forest structure as well as the disturbances to the forest. Figure 8.3 provides a view 
of a wider area of mangroves on Cape Lopez Bay. This map was prepared from satellite data and 
used aerial photographs such as that shown in Figure 8.2 to aid interpretation. 

The local topography determines small depressions or slightly elevated land where mangrove 
trees are absent. These 'equatorial tannes', often dominated by the succulent halophyte Sesuvium 
portulacastrum, are quite extensive throughout the Gabon mangroves. On the other hand, the 
salinity of the water table and that of the interstitial waters is usually high (twice that of the free 
water). The presence of empty corridors, about 10 to 15 m wide and 100 to 500 m long, can be 
observed in several mangrove areas of Gabon, such as the Mondah and Gabon estuaries. These 
are the result of seismic oil exploration activities. One of the major reasons why mangroves have 
not been re-colonised in these areas could be related to the compactness of the soil. 



Environmental data 

• Mean annual rainfall 

• Dry season 

• Fresh water discharge 

• Temperature 

• Air humidity 

• Mean water salinity 

• Soil types 

• Average tidal amplitude 

• Total areal extent 

• Average population density 

• Dominant mangrove types 



• Extent of salt marshes 



2,000-3,400 mm/year 

2-4 dry months 

High and evenly distributed 

Mean of coldest month >20°C (mean annual temperature variation <5°C) 

Constantly high (>80%) 

<20-30% 

Usually clayey-loamy under the best mangrove stands 

(30 - 40% of clay and loam) 

1.5 m 

2,500 sq km 

<5 people/km 

- tall dense Rbizopliora harrisonii and R. racemosa stands 
(>20 m in height) 

- extended tall heterogeneous Avicennia germinans communities 

- very extended dwarf R. harrisonii thickets (3-5 m in height) 
<5% of the total mangrove area 






i36 



World Mangrove Atlas 








^M^-^^Jl^j '^ 



Plate 8.1 A conspicuous inner Rhizophora harrisortii belt 



W 



N'Dougou Bay 



Alewana Plain 



Rliizoplu^rn liiini^tiiii 



Ai'iceiiiiiil ifcnjiiiiaus 




Rhizophora harrisonii 



5,0 



50 m 15 tn 



Figure 8.1 An east-west transect across the mangroves on the east coast of N'Dougou Bay 



West Africa 



137 




Figure 8.2 The deltaic mangroves of Gabon: Cape Lopez Bay 

This is an aerial photograpli at approximately 1:30,000 showing the seismic transects and oil pumping 
platforms in the mangroves of Gabon 



J38 



World Mangrove Atlas 



PORT GENTIL 



NTCHENGUE 



^; \ 



ATLANTIC 
OCEAN 



^^M Dense tall mangrove 

^H open low mangrove 

ll^'J Shrubby mangrove type 



f'iPE LOPEZ 




ILE MANDJI 







Ouanga Lake 



+ 



LAMBARENI O 



©ACriMAGE©ICIV-CNRS/UPS pourelF gabon 



Figure 8.3 The mangroves of Cape Lopez Bay, Gabon 



West Africa 139 



Case study 



The riverine mangroves of Gambia 

The mangroves of Gambia were well documented in 1984 (Figure 8.4) when the Gambian-German 
Forestry Project (GGFP) undertook an accurate inventory and mapping project at 1:10,000 scale. 
This work began in October 1980 with the acquisition of a colour infrared aerial coverage. In 
addition to the mapping work, an extensive report on the mangroves of this small country was 
also published in 1981 (Checchi and Co., 1981). Figures 8.5 and 8.6 show recent SPOT satellite 
pictures of the mangroves in Gambia. 

Beautiful mangrove stands, reaching to over 20 m in height, can be observed between 100 and 
160 km upstream from the sea, especially near Tendaba, Elephant Island and Dan Kun Ku Island, 
where the average salinity of the water during the dry season is about 10%a 

Along the almost flat topography of the Gambia River valley, several mangrove formations exist, 
from the estuarine formations found near the capital Banjul to the tall fluvial formations found some 
160 km upstream from the ocean (lower river and MacCarthy Island divisions). A large water 
catchment and a high, almost constant, freshwater supply maintain some of the best mangrove 
stands presently found in West Africa. Direct human impact is limited, except near Banjul. However, 
the exceptional dryness that affected the African continent in the 1970s, caused deterioration of 
the mangroves of Gambia, especially those found near the river tributary, Bintang Bolon. A high 
mortality of the mangroves occurred, presumably due to deeper tidal penetration and accompa- 
nying increased water and soil salinity (Plate 8.2, Figure 8.7). About 20 sq km of mangroves were 
destroyed. 

From an ecological point of view, the mangroves are probably extremely sensitive to minor 
changes in the tidal regime and in the volume and frequency of the freshwater input. The mangroves 
play an important role in the fisheries of the river and estuary. The tall mangrove areas of Gambia 
(height over 20 m) represent an important sustainable source of forest products. These systems 
are highly productive and it might be possible to utilise and manage the Rhizophora stands of the 
lower Gambia River basin on a 30 year rotation. Out of 497 sq km, which is the present area of 
mangroves in Gambia, tall forest probably covers 300 sq km. 



Environmental data 

Mean annual rainfall 1,000-1,300 mm 

Dry season 6-8 consecutive dry months (November-May) 

Water salinity Minimum 5%o upstream, maximum 33%o (mouth of the river) 

pH of the topsoil 5 to 7 

Dominant soil type Clayey 

Mean tidal amplitude 1-2 m 

Areal extent 600 sq km in 1982, less than 500 sq km in 1995 (saltmarshes and 

blanks make up 3% of the total mangrove area, and crops less than 5%) 

Average population density 5 people/sq km 

Dominant mangrove type Tall riverine mangrove type (>20 m height) 

Main mangrove species Rhizophora harrisonii, R. racernosa, Avicennia germinans 

Average standing stock 100-150 m^/ha 



140 



World Mangrove Atlas 




KAIM8UJAE 
13°15'N 



I Mangrove forest |' ;■; | Main mortality area along the Bintang Bolon 



Main roads 



Tracks 



Figure 8.4 Distribution of mangroves in Geunbia 




Figure 8.5 SPOT satellite image. Tiie mangroves along the lower Gambia River (in red) surrounded 

by savannah and crop land 

White and black 'holes' in the vegetation cover are due to mangrove mortality either on dry soils 
(white) or on flooded areas (black) 



West Africa 



141 




Figure 8.6 SPOT satellite image 

As Figure 8.5, showing greater detail (prepared using Multiscope software) 




Plate 8.2 A view of mass mortality in the mangroves of Gambia 



142 



World Mangrove Atlas 



MAIN ZONES OF UORTAUTY 




pH7 
water salinity 25% 



salinity 31 %o (normal) 
Top soil pH 5.5 



barren land extension 



Figure 8.7 Mortality and distribution of mangrove plants at Darusalam, Bintang Bolon (Gambia) 

A Previous mean high tidal level (twice a day) 

A' Present mean high tidal level (twice a day) 

a Previous mean low tidal level 

a' Present mean low tidal level 



I Rhizophora harissonii and R. mucronata dead or dying, practically no regeneration 

II Rhizophora mangle almost monospecific, good regeneration, low mortality 

III Rhizophora mangle and Auicennia intermingled, healthy, good regeneration 

IV Avicennia only, healthy, good regeneration 

V Auicennia zone totally destroyed without any regeneration 

VI Barren, high soil salinity, arid conditions 

VII Orchards (oil palm {Elaei guineensis), Ficus etc.) on well drained soils 



West Africa 143 

Ghana Map 8.2 

Land area 238,540 sq km 

Total forest extent ( 1 990) 95,550 sq km 

Population ( 1 995) 1 7,453,000 

GNP(1992) 440 US$ per capita 

Mean monthly temperature range 24-30°C 

Mean annual rainfall 1,250 mm 

Spnng tidal amplitude (Takoradi) 0-3-1 6 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 100 sq km# 

Area of mangrove on the map 214sqkm 

Number of protected areas with mangrove 

In Ghana, mangroves are mainly limited to stands around lagoons on the west coast of the country and bordering 
the lower reaches and delta of the Volta River. They are best developed on the west coast between Cote d'l voire 
and Cape Three Points. Open lagoons are often dominated by Rhizophora, while closed lagoons, which have an 
elevated salinity, contain Avketmia ^erminans, Conocarpus erectus, Lajiuncularia racemosa and Acrostichum aureum.The 
mangrove stands in most areas are secondary growth with degraded faunal composition due to intensive use 
of the mangrove for fuelwood to smoke fish and extract salt. Mangrove wood is also used for construction. 
Mangrove lands have been reclamied for agriculture and urbanisation. There is a threat from oil pollution. The 
relatively dry climate of Ghana means that the coastal areas are dominated by savannah. 

Map reference 

Digital data set entitled West African Forest Data compiled by Henrik Olesen of UNEP-GRID from AVHRR imagery 
(1 km pixels), for the TREES (Tropical Ecosystem Environment Observations by Satellite) project of the EC Joint Research 
Centre, Italy. A crude estimate of the mangrove coverage in the Volta Delta has been added. 

Guinea Map 8.1 

Land area 245,860 km 

Total forest extent (1 990) 66,920 sq km 

Population (1995) 6,700,000 

Mean monthly temperature range 23-32°C 

Mean annual rainfall 4,500 mm 

Spring tidal amplitude (Conakry) 0.5-3.7 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 2,963 sq km# 

Area of mangrove on the map 3,083 sq km 

Number of protected areas with mangrove 

Mangroves are located all along the coast of Guinea. The subsidence of the coastal region has favoured the 
deposition of sediment and the flooding of river mouths. The tide penetrates far upstream and forms many 
narrow inlets by partial submergence of river valleys. The mangroves stretch along these narrow inlets and into 
the bays at the river mouths. The mangroves are extensive for about 10 kin inland and they can be found up 
to 40 km from the coast on the larger rivers. Rhizophora can be found growing to a height of 20 m in some 
areas but in other areas the trees rarely get above 8 m and are often much smaller. As in the other countries of 
this region rice growing is widely practised in the mangrove areas and this is often combined with fish farming. 
Salt extraction is a seasonal activity and mangrove wood is often used as fuel. It is estimated that 1 ,400 sq km 
of mangrove swamp has been converted to rice fields. By 1993, 620 sq km had been abandoned. Most of this 
area remains barren ot has thin cover of salmiarsh plants. 

Map reference 

The data are denved from 1979-80 aerial photography, updated using Landsat MSS 1984-1985-1986 iinagery. 
CTFT/BDPA-SCET AGRI {\989) . Potcntialith et Possibilites de Relancc de I'Aclivite Forcstiere: Synthese Regionale et Nationak. 
1:700,000. CTFT/BDPA-SCET AGRI. 



144 World Mangrove Atlas 

Guinea-Bissau Maps.i 

Land area 36, 120 sq km 

Total forest extent ( 1 990) 20,2 1 sq km 

Population (1995) 1,073,000 

GNP(1992) 210 US$ per capita 

Mean monthly temperature range 24-27°C 

Mean annual rainfall 1,750 mm 

Spring tidal amplitude (Caio) 2,30m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 2,484 sq km# 

Area of mangrove on the map 3,649 sq km 

Number of protected areas with mangrove 

Guinea-Bissau is generally low lying, rising from sea level in the west to low mountains in the east. The coastal 
zone represents an important resource with its numerous estuaries surrounded by mangrove swamp forests. It 
is inhabited by numerous ethnic tribes and about 60% of the population live in this region. Guinea-Bissau has 
the same mangrove species as Senegal except that Acrostichum aiireum is not found. Salt marshes or herbaceous 
'tannes' exist and species o( Sesuvium are dominant. The tidal influence is felt 150 km inland and defines the 
limit of the mangroves. The most extensive mangrove forests are in the north of the country. The area of 
mangrove may have declined by as much as 20% since 1973 mainly due to conversion for rice farming. The 
growing of rice on mangrove soils has a long tradition and sea water is allowed to enter the rice fields during 
the dry season to reduce the acidity of the soil. Fish and crustaceans collected from the mangrove estuaries are 
the main source of protein in the coastal villages. Firewood, construction timber and medicinal products are 
also obtained from the mangroves. The construction of numerous anti-salt barriers to extend commercial rice 
production is having an adverse affect on many mangrove areas. 

Map reference 

Information taken from a generalised map (c. 1:1, 000,000) hand drawn by Scott Jones in 1990, based on IGN (1981), but 

updated to show forest loss. 

IGN (1981). Cuinee Bissau. 1:500,000. Instituto Geografico Nacional. 

Liberia Map 8.2 

Land area 96,320 sq km 

Total forest extent ( 1 990) 47,900 sq km 

Population (1995) 2,600,000 

GNP ( 1 992) 440 US$ per capita 

Mean monthly temperature range 24-29°C 

Mean annual rainfall 4,600 mm 

Spnng tidal amplitude (Monrovia) 2-1 .3 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 190 sq km# 

Area of mangrove on the map 427 sq km 

Number of protected areas with mangrove 

Mangroves are not extensive in Liberia but they do occur at the mouths of the rivers and in some of the lagoons. 
Lake Piso, a very large open lagoon near the border with Sierra Leone, supports a series of mangrove swamps. 
The lagoon mangrove coinmunities around Cape Palmas in southeastern Liberia can attain a height of 3 in 
and are dominated by Conocarpus erectus with only rare specimens o{ Avicemiia germinans and Rhizophora racemosa. 
Thickets oi Acrostichum aureum are also cominon. On the central Liberian coast estuarine mangroves occur, 
consisting of stunted Rhizophora harrisonii, Avicennia germinans and Conocarpus erectus. The mangroves of Liberia 
have suffered from road building, landfill and fuelwood collection. Rhizophora racemosa seems to have been 
eliminated in some places by extensive felling. At present, none of the mangroves are in a protected area. 

Map reference 

Digital data set entided West Afncan Forest Data compiled by Hennk Olesen of UNEP-GRID from AVHRR imagery 
(1 km pixels), for the TREES (Tropical Ecosystem Enviromiient Observations by Satellite) project of the EC Joint Research 
Centre, Ispra, Italy. Further minor edits were provided by Francois Blasco. 



West Africa 145 

Mauritania Map 8.1 

Land area 1,025,520 sq km 

Total forest extent ( 1 990) 5, 540 sq km 

Population (1995) 2,335,000 

GNP(1992) 520 US$ per capita 

Mean monthly temperature range 2 1 -30°C 

Mean annual rainfall 139 mm 

Spnng tidal amplitude (Port Etienne) 0.5-1.5 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 10 sq km 

Area of mangrove on the map 1 .04 sq kmtf 

Number of protected areas with mangrove 2 

Mangrove communities are somewhat limited in extent in Mauritania, but those that do occur represent the 
northernmost and the most arid mangrove systems on the Adantic coast of Africa. There are two centres of 
mangrove distribution, one along the Senegal River Delta, which has a sahelian climate, the other further north 
around Cape Tiimrist and the Banc d'Arguin National Park. These two areas are separated by a coasdine 
consisting of sandy beaches backed by a high ridge and exposed to strong wave action. In the Senegal River 
Delta Rhizophora racemosa is dominant along the creeks and Ai'kctmia germinam covers the back swamps, possibly 
with some specimens of Conocarpus erectus. The northern stands consist of a few hundred hectares of pure 
Avicennia germinans, and may well be relict from an estuarine past. Trees are dwarfed, rarely exceeding 2 m in 
height, and the stands may be in decline as levels of recruitment are very low. The mangroves have also declined 
considerably in the Senegal Delta, a fact which has been related to over-exploitation for firewood and boat 
construction by local populations; increased grazing pressure by camels and goats, combined with reduced 
flooding, both of which can be related to the sahehan droughts; and the increased salinity of the river basin as 
a result of the construction of the Diama dam near the Senegal River mouth. Since 1993 it appears that 
regeneration of mangrove communities may have occurred in some areas. (Main source: O. Hamerlynck,pers. 
comm., 1995.) 

Map references 

Mangroves were annotated from sketch maps in Gowthorpe (1993) and YeUi (1995), kindly provided by O. Hamerlynck, 
UICN Mauritanie. 

Gowthorpe, P. (1993). Une visite au Pare National de Banc d'Arguin. 193 pp. 

Yelli, D. (1995). Formations morphopedologiques et les unites floristiques de has delta mauritanien. Paper presented at the 
Colloquium 'Biodiversite du Littoral Mauritanien', Nouakchott, 12-13 June, 1995. 

Nigeria Map 8.2 

Land area 923,770 sq km 

Total forest extent ( 1 990) 1 56,340 sq km 

Population ( 1 995) 1 26,929,000 

GNP(1992) 320 US$ per capita 

Mean monthly temperature range 24-27°C 

Mean annual rainfall 2,000 mm 

Spnng tidal amplitude (Escravos) 0.3-1 .6 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1 995) 1 0,5 1 5 sq km# 

Area of mangrove on the map 11,1 34 sq km 

Number of protected areas with mangrove 

Nigeria has the largest area of mangroves in Africa and mangrove swamps stretch along the entire coastline, 
which is characterised by high rainfall and humid conditions. The largest expanse of mangroves is found in the 
Niger Delta between the region of the Benin River in the west and the Calabar, Rio del Rey estuary in the 
east. A maximum width of 30 to 40 km of mangroves is attained on the flanks of the Niger Delta, which is 
itself a highly dynamic system. Two large lagoons, Lagos and Lekki, dominate the coastal systems in the west of 
the country. Both are fringed by mangroves, backed, in turn, by swamp forests. In the far east of the country 
there is a second major delta/estuary system associated with the Cross River which also has a considerable area 
of mangroves extending in a belt of 7-8 km on either side of the estuary and up to 26 km in the deltaic zone 
at the head of the estuary. In the lagoons and deltas, Rhizophora racemosa is the most abundant mangrove, with 
Avicennia germinans, R. harrisonii and R. mangle only sparsely represented. In the estuaries the species composition 
may be different and Nypafruticans,in introduced species, becomes more abundant. The mangroves rarely exceed 
more than 10-12 m in height but can on occasion reach more than 40 m. Fishing is an important activity in 



146 



World Mangrove Atlas 



most mangrove areas. The major threats being experienced by mangroves are those resulting from oil pollution 
and uncontrolled wood exploitation. Oil and gas installations are spread throughout the central and western 
parts of the Niger Delta and there are four tanker ports at the delta face. 

Map reference 

Digital data set entitled West African Forest Data compiled by Hennk Olesen of UNEP-GRID from AVHRR imagery 
(1 km pixels) , for the TREES (Tropical Ecosystem Environment Observations by Satellite) project of the EC Joint Research 
Centre, Ispra, Italy. 



Sao Tome and Principe 



Map 8.2 



Land area 

Total forest extent (1990) 

Population (1995) 

GNP(1992) 

Mean monthly temperature range 

Mean annual rainfall 

Spring tidal amplitude 

Alternative estimate of mangrove area 

Area of mangrove on the map 

Number of protected areas with mangrove 

No information on the presence of mangroves. 
Map reference 

No data 



960 sq km 

570 sq km 

133,000 

350 US$ per capita 

23.9-26.1°C 

951 mm 

0.5-1 .9 m 

No information 

No data 





Senegal 



Map 8.1 



Land area 196,720 sq km 

Total forest extent ( 1 990) 75,440 sq km 

Population (1995) 8,387,000 

GNP(1992) 780 US$ per capita 

Mean monthly temperature range 1 5-28°C 

Average rainfall range (Casamance) 691-1,371 mm 

Average rainfall range (St Louis) 95 342 mm 

Spring tidal amplitude (Dakar) 3-1 .6 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 1,853 sq km# 

Area of mangrove on the map 1 ,830 sq km 

Number of protected areas with mangrove 2 

The mangroves of Senegal are largely estuarine and occur in two main regions: the estuaries of the Saloum and 
the Casamance. These are both reverse estuaries as the salinity upstream in the dry season is often two to three 
times the salinity of the neighbouring sea water. There are often salt marshes behind the mangroves with species 
ofSesuuium, Paspalum, Sporobulus, Scirpus and Philoxerus present. Mangrove areas have been traditionally used for 
rice growing, fishing, fish culture, shell picking and wood. Senegal has been affected by drought since 1963 and 
this has had an adverse effect on the mangroves leading to a decrease in the total area. Intensification of 
agriculture and increasing population pressure have resulted in increased erosion and siltation. 

Map reference 

The main source map (USGS, 1985) was kindly made available to WCMC by the EDC Intemational Projects Department 
of the EROS Data Center, and was compiled from the interpretation of Landsat imagery of different dates and from 
extensive ground surveys. A small northern extension to a Casamance tributary at the eastward end of that estuary was 
based on a sketch from Franfois Blasco. 

USGS (1985). Range and Forest Resources of Senegal. 1:1,000,000 scale. Digital map prepared for the US Agency for 
International Development (USAID) by the US Geological Survey National Mapping Division, EROS Data Center 



West Africa 147 

Sierra Leone Map 8.1 

Land area 71,740 sq km 

Total forest extent ( 1 990) 1 8,890 sq km 

Population (1995) 4,740,000 

C5NP(1992) 170 US$ per capita 

Mean monthly temperature range 28-32''C 

Mean annual rainfall 9,000 mm 

Spring tidal amplitude (Freetown) 0.4-3 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1 995) 1 ,838 sq km# 

Area of mangrove on the map 1 ,695 sq km 

Number of protected areas with mangrove 

The rich mangrove forests of Sierra Leone have been heavily exploited due to rapid population increase and 
the poor economic performance of the country. The mangrove species and saltmarsh species found in Sierra 
Leone are the same as those found in Senegal. The most extensive mangrove stands are in the northern part of 
the country and major locations are Yawn Bay, the estuaries and islands behind Freetown and the complex of 
coasthne and estuaries behind Sherbro Island which join into a wide waterway known as Sherbro River. The 
mangroves extend far up the rivers to the extent of the tides. Rhizophora mcemosa is commonly found in 
association with Avicennia on mudflats, but in areas where the soil is well consoUdated and there is an input of 
freshwater R. racemosa grows exclusively, sometimes to a height of 35 m. Large scale erosion in some mangrove 
areas has occurred due to deforestation, often to provide new areas for rice production. Fish smoking is a major 
way of preserving food and cheap fuel from the mangroves is used for this purpose. Similarly, mangroves supply 
cheap fuel for salt production. Siltation and pollution of estuaries pose a major threat to the mangrove 
communities. 

Map reference 

Digital data set entitled West African Forest Data compiled by Henrik Olesen of UNEP-GRID from AVHRR imagery 
(1 km pixels), for the TREES (Tropical Ecosystem Environment Observations by Satellite) project of the EC Joint Research 
Centre, Ispra, Italy. 

Zaire Map 8.3 

Land area 2,345,410 sq km 

Total forest extent (1990) 1,132,750 sq km 

Population (1995) 43,814,000 

GNP(1990) 220 U5$ per capita 

Average temperature 25'C 

Mean annual rainfall 800 mm 

Spring tidal amplitude 3-1.6 m 

Alternative estimate of mangrove area (Saenger and Bellan, 1995) 226 sq km# 

Area of mangrove on the map 374 sq km 

Number of protected areas with mangrove 

Zaire is Africa's third largest country, but has only a tiny coasdine of less than 40 km at the mouth of the Zaire 
River. The coast is generally of high relief, but mangrove stands occur where the cliffs are breached by coastal 
rivers and streams. The main mangrove area occurs in the estuary of the Zaire River. The tidal forests are 
dominated by Rhizophora racemosa in the frontal zone and by R. harrisonii and R. mangle in the middle zones. 
The first two species can reach heights of 25-30 m. The Rhizophora forests merge into fresh water swamp forests 
some of which are weakly tidal. The Zaire River estuary is sparsely populated and there has been little degradation 
of the mangroves. There have been some reports of oil pollution from the oil terminals in the adjacent Cabinda 
enclave of Angola. 

Map references 

Digital data were provided by NASA/GSFC and the University of Maryland, USA (n.d.). Mangrove areas were estiinated 
from the closed moist forest coverage by overlaying White (1983). 

NASA/GSFC and the University of Maryland (n.d.). Derived from 1 km resolution NOAA/AVHRR 1988 data. Produced 

at NASA, Goddard Space Flight Center. 
White (1983). The Vegetation of Africa. Unesco/AETFAT/UNSO. Unesco, Pans, France. 



148 World Mangrove Atlas 



Case study 



Sahelian mangroves in Sine-Saloum, Senegal 

The most northern mangroves presently found in West Africa are in Mauritania (Map 8.1) where 
a few stunted bushes of Avicennia germinans are still found in the Banc d'Arguin National Park, 
at about 20° north, growing in near-desert conditions and without noticeable freshwater supply. 
They are considered as remnants of moister climatic conditions. In this part of Africa, palaeontol- 
ogists have described a continuous drying of the climate for the past 35,000 years. Most of the 
mangrove forests of Mauritania and northern Senegal disappeared during the Nouakchottian 
period, 6,500 years ago. 

Several hundred kilometres further south, the mangroves of Sine-Saloum (Map 8.1, see insert 
1) represent today the most northern of the large mangrove forests in the region. They are also 
the most exposed to the local climatic change and aridification. Figure 8.9 shows the classical 
zonation of these mangroves. The average annual rainfall (700-1,000 mm) and the eight 
consecutive dry months of the dry season create semi-arid conditions. The recent exceptionally 
dry years (300-500 mm rainfall per year) induced increased soil and water salinities and almost all 
woody halophytes have been affected. When the mean salinity of the water exceeds 40%o, 
Rhizophora mangle tends to disappear and the resulting mangrove community is limited to a low 
stand of scattered Avicennia bushes (Plate 8.3). 

The general result of increasing salinity, due to worsening of climatic conditions and to freshwater 
diversion for human use, is reduced plant growth, lower organic matter production, the gradual 
substitution of mangrove species by other, more salt tolerant, species and the extension of salt flats 
(blanks or tannes) where the natural re-establishment of mangrove seedlings is impossible. 

Between 1980 and 1991 the extent of barren soils in the Sine-Saloum increased by 3% and that 
of cultivated areas by 5% (Figures 8.8 and 8.11). The two maps illustrating the distribution of 
mangroves in the Sine-Saloum provide a useful comparison between the data obtained from 
Landsat MSS (Figure 8.8) and SPOT-HRV (Figure 8.11). While the former is generally considered 
highly accurate, SPOT provides the highest resolution and allows improved identification of 
mangrove types and related land uses. The average rate of deforestation in the mapped areas is 
about 8% per year which is quite high, especially as the mangroves are included in the National 
Park of Saloum Delta. The most affected areas are located between the Saloum and Diombos 
Rivers where large areas have been drained during the last decades to provide land for agriculture. 
Clearing land for agriculture (food crops, groundnuts, oil palms), wood extraction by the increasing 
local population and drastic climatic conditions seriously threaten the mangroves in this area (Figure 
8.10) (Plate 8.4). 



Environmental data 

• Mean annual rainfall 700-1,000 mm/year 

• Dry season 8 consecutive dry months (November-June) 

• Water salinity Minimum 25%o to maximum probably >90%o 
■ pH of the topsoii 7 

• Dominant soil types Mainly sandy on the seaward side, loamy-clayey upstream 

• Average tidal amplitude <0.5 m 

• Total areal extent About 55 sq km 

• Average population density 65 people/sq km 

• Dominant mangrove type Estuarine. Low (3-5 m in height), dense formations 

• Main mangrove species Rhizophora racemosa, R. mangle, Avicennia germinans 



West Africa 



149 




Areas without mangroves 
Mangroves 



_ , 2 4km 
Scale I I I 



© I.C.I.V. (Toulouse ■ FRANCE) 1994 

Figure 8.8 Mangroves of Sine-Saloum, Senegal, taken from Landsat MSS 1980 



Realization : J.L. CARAYON 



150 



World Mangrove Atlas 



5 6 7 



6m _. 



4^. .i^^. 




barmn land 




Figure 8.9 Classical zonation of Sahelian mangroves 



(mangrove rBmnants) 




Figure 8.10 Landscape, near Niodor (Sine-Saloum), illustrating the extension of agriculture, notably 
groundnut and oil palm plantations 



Main water bodies 



Barren lands including salt flats 



Main dense mangrove areas 



Cristallized sodium chloride 



Areas with low mangroves, 
often degraded (mainly Avicennia) 



p Crops (mainly ground nuts) 

L or plantations on sandy soils 

UHll Mosaics of crops and barren lands 



Mainly grassy halophytes 



Tree savannas generally with 
Adansonia digitata (Baobabs) 
and shrubby Acacia 



© I.C.I.V. (Toulouse - FRANCE) 1994 



Realization: J.L. CARAYON 



Legend to Figure 8.11 



West Africa 



i51 




Poitite de 
Sangomar 



1.C.I.V. (Toulouse - FRANCE) 1994 



Realization : J.L. CARAYON 



Figure 8.11 Mangroves of Sine-Saloum, Senegal, taken from SPOT data, 1991 



152 



World Mangrove Atlas 




Plate 8.3 Scattered dying stand of Avicennia germinans 




Plate 8.4 



Mangroves of Senegal badly affected by clearing for agriculture 



West Africa 753 



Sources 



Blasco, F. (1993). Manj^roves of Senei^al and Gambia: Ecohj^ical Status and Evolution. Paul Sabatier University, Toulouse, 
France. 86 pp. 

Checchi and Co. (1981). Mangrove Feasibility Study. Gambia forestry project No. 635-0205. Final report, 11 Sept. 
Washington DC. 152 pp. 

Diop, E.S. (1990). La Cote Quest- Africaine: du Saloum (Senegal) a la Mellacorce (Rep. de Cuinee). Editions de I'ORSTOM, 
Pans. 379 pp. 

Diop, E.S. (1993). Conservation and Sustainable Utilisation ofMani;<rove Forests in Latin America and Africa Regions. Part U: 
Africa. Mangrove Ecosystems Techmcal Reports No. 3. International Society for Mangrove Ecosysteins, Okinawa, 
Japan. 262 pp. 

Elf Gabon (1994). La mangrove. Resource Utile, Resource Fragile. Fromard, F and Fontes.J. (Eds). ICIV/CNRS, Paul 
Sabatier University, Toulouse, France. 

Fontes.J. and Fromard, E (1993). Cartograplue de la vegetation de la baie de Port-Gentil (Cap-Lopez, Pointe Fetiche). 

Elf Gabon and ICIV Toulouse, France. 
Fromard, F and Fontes,J. (1994). Structure ct Dynamique dcs Mangroves de la Region de Port-Centil, Gabon. Laboratoire 

d'Ecologie Terrestre. University Paul Sabatier. Toulouse, France. 52 pp. 
Fromard, E, Pontes, J. and Louis, A. (1993). Etude environnementale de la region de Port-GentU (Gabon): structure et 

dynamique des mangroves et de la vegetation encadrante. Analyse de I'impact He a I'activite petroliere. Elf Gabon 

and ICIV, Toulouse. 
GuUlemyn, D, Martel, C, Flouzat. G. and Blasco. E (1987). Etude des forets de berge de Gamble et des criteres de 

detection de la mortalite. In: SPOT 1 - Utilisation des images, bilan, rcsultats. Pans. pp. 113-120. 
Hughes. R.H. and Hughes. J.S. (1992). A Directory of African Wetlands. lUCN. Gland, Switzerland and Cambridge, 

UK/UNEP Nairobi, Kenya/ WCMC, Cambridge, UK. 820 pp. 
Johnson, M.S. (1978). Inventory of Mangroves above the proposed Gambia River Barrage at Yelitenda, The Gambia. Project 

report 54, Land Resources Development Centre, Surbiton, Surrey, UK. 105 pp. 
Lebigre.J.M. (1983). Les mangroves des rias du httoral gabonais. Essai de cartographie typologique. Bois et Forets des 

Tropiques 199:3-28. 

Lebigre,J.M. (1990). Les Marais Maritimes du Gabon et de Madagascar. Doctoral thesis. State Umversity of Bordeaux 

III, vol. 1: 1-185; vol. 2: 187-405; voL 3: 408-651. 
Marius, C. (1985). Mangroves du Senegal et de la Gamble: Ecologie, Pedologie, Geochimie, Mise en Valcur et Amenagement. 

ORSTOM (Paris). Travaux et documents n" 193. 356 pp. 

Saenger, P. and BeUan, M.E (1995). The Mangrove Vegetation of the Atlantic coast of Africa. Universite de Toulouse Press. 

Toulouse. 96 pp. 
Sayer.J.A., Harcourt. C.S. and Collins. N.M. (Eds). (1992). The Conservation Atlas of Tropical Forests: Africa. Macmillan 

Press. London. 288 pp. 
Teas, H J. (1982). An epidemic dieback gall disease o( Rhizophora mangroves in the Gambia, West Africa. Plant Diseases 

66: 522-523. 



154 



World Mangrove Atlas 




o 
a 

"3 



s 



% 



I 

u 

o 
Z 



00 



West Africa 



155 




o 



0) 

.c 






IS 



156 



World Man<iravc Atlas 




Map 8.3 Southwest Africa: Nigeria to Angola 



9 



East Africa and the Middle East 



This region includes the entire east coast of Africa from South Africa to Egypt; it also includes the coasts of the 
Arabian Peninsula and Iran, together with the scattered mangrove communities of the Indian Ocean islands. 
This region is dominated by arid coastlines and so, despite having a long coastline, it has a relatively small area 
of mangroves. The total area of mangroves in the region is some 10,024 sq km, or 6% of the total global area. 
There are also relatively few species, which could be related to the harsh environmental conditions as much as 
to other historical and biogeographic factors. 

In the Red Sea and the Gulf, despite the low diversity and relatively low total areas, the mangroves are of 
considerable interest and often represent the only forest habitats in the coastal areas of these countries. 
Furthermore, many of these mangroves are growing in areas of high seawater salinities, minimal freshwater 
input, and both hot and cold temperature extremes. Typically, these mangroves are stunted and cannot be used 
for timber. However, they are used for grazing and firewood. Fisheries, withm the mangroves and offshore, are 
often very important. Arab, Somali, Persian and Indian traders export mangrove timber, primarily for boat 
building, from Kenya, Tanzania and Mozambique, in a trade that dates back to the ninth century. 

On the Indian Ocean islands, the development of mangroves is very variable. The variation can often be 
related to either the morphology of particular islands, or to their isolation. The very steeply shelving rocky 
shores of some islands provide Uttle space for mangroves to develop, and the most remote islands are perhaps 
too isolated for large-scale mangrove establishment, especially if they are regularly affected by tropical cyclones. 
East Africa, particularly Kenya, Tanzania, Mozambique and the western coast of Madagascar, has the best 
developed mangroves in terms of area, species diversity and forest structure. 

In general, mangroves in this region appear to be less threatened by man than elsewhere, although detailed 
information is scarce for a number of countries. The harsh environmental conditions in many areas mean that 
coastal populations are not large and there is little pressure to convert mangroves to other uses. Aquaculture has 
not become widespread as it has in other regions. Some mangrove areas have been lost to urbanisation. Other 
areas have been severely degraded by salt extraction, overgrazing, unsustainable collection of fuelwood or 
pollution from oil or urban sources. Population growth in some areas will increase these pressures. 

Although there are no general texts describing the mangroves of the region as whole, certain countries are 
described by Hughes and Hughes (1992) and by Sheppard et al. (1992). 



158 



World Mangrove Atlas 



Table 9. 1 Mangrove species list for East Africa and the Middle East 





1 


s 

o 

c >, 

OJt- 


1 

E 
o 
u 


1 


Q. 
cn 

UJ 




c 
2 


1 


2 


(0 

5 


3 




E 

o 


1 
3 


5 

(0 

< 


-C 


1 

o 


1 

O 


c 


J 


1 
< 

c 
Z5 


1 


Acrostichum aureum 


















• 


















• 










Avicennia marina 


• 






• 


• 


• 


• 


• 


• 








• 


• 


• 




• 


• 


• 




• 


• 


Bruguiera cylindrica 














































Bruguiera gymnorrhiza 


















• 




• 














• 


• 


^ 




Ex 


Ceriops tagal 












• 






• 


















• 










Excoecaria agallocha 














































Heritiera littoralis 


















• 




























Lumnitzera racemosa 




• 














• 


















• 










Pemphis acidula 




• 










































Rhizophora mucronata 










• 


• 


• 




• 




• 








• 






• 


• 






• 


Rhizophora racemosa 






























' 
















Sonneratia alba 


















• 




























Sonneratia caseolaris 




















• 


























Xylocarpus granatum 


















• 





























Ex Extinct in that 


country 








1 Introduced 










Country sources 








Bahrain 




Sheppardeta/., 1992 


Mozambique 


Hughes and Hughes, 1992 


British Indian Ocean Territory 


Bellamy, 1979 


Oman 


Sheppard eta/., 1992 


Comoros 




No data 


Qatar 


Sheppard et a/., 1992 


Djbouti 




MEPA, 1987 


Saudi Arabia 


Sheppard eta/., 1992 


Egypt 




MEPA, 1987 


Seychelles 


various WCMC files 


Eritrea 




MEPA, 1987 


Somalia 


Hughes and Hughes, 1992 


Iran 




Khosravi and Motalebi, 1994 


South Africa 


Hughes and Hughes, 1992 


Kenya 




Ruwa, 1993 


Sudan 


MEPA, 1987 


Madagascar 




Marguerite, 1993 


Tanzania 


Semesi, 1993 


Maldives 




NIO, 1991 


United Arab Emirates 


Sheppard eta/., 1992 


Mauritius 




Blasco, pers. comm., 1995 


Yemen 


MEPA, 1987 and M. Rands, pers. comm., 1992 



The Gulf and the Gulf of Oman 



Map 9.1 



The Gulf, variously known as the Arabian Gulf and Persian Gulf, is a wide, shallow body of sea to the north 
of the Indian Ocean, separated from the latter by the Gulf of Oman and the Straits of Hormuz. The Gulf of 
Oman represents a relatively narrow northern extension of the Indian Ocean. The countries under consideration 
are Bahrain, Iran, Iraq (no mangroves), Kuwait (no mangroves), Oman, Qatar, United Arab Emirates, and the 
east coast of Saudi Arabia. The coastlines in the region are all arid or hyper-arid and there is very Utde freshwater 
input other than that in the far north from the Shatt al Arab and associated rivers. Seawater salinities are higher 
than in the open ocean. Tidal ranges are generally less than 1 m, although they can reach 2 m in some areas. 
Temperature ranges are considerable and cool temperatures, together with high salinity, may be responsible for 
restricting mangrove distribution. 

Only one species of mangrove is found in the Gulf, Avicennia marina, which is very tolerant of the highly 
saline conditions, while Rhizophora mucronata is reported from the Cyrich estuary on the Iranian coast of the 
Gulf of Oman. The northernmost natural Umit for mangroves is about 27° N, which is close to the most southerly 
occurrences of ground frost in the region. Interestingly, there have been efforts to grow Rhizophora racemosa on 
the Saudi Arabian coast to the north of this (28°30'N) at Ras al Kha^i. Mangroves are largely restricted to 
sheltered locations behind reefs or in creeks or embayments, and are not widespread, for example covering only 
1% of the Gulf coasdine of Saudi Arabia. In most areas they are unproductive, and are typically stunted, reaching 



East Africa and the Middle East i 59 

only 1-2 m in height. The best developed stands of mangrove are found in Iran and Oman, the former notably 
m the Kuran Strait and on the coast of Qeshm Island, the latter m scattered but fairly dense stands on the 
northeast coast and some small stands with trees reaching 6 m in height on the southeast coast. Despite their 
limited extent, mangroves in the Gulf were the first to have been recorded anywhere in the world Uterature, 
described by Nearchus and Theophrastus over 2,000 years ago. There is very htde human use of the mangroves 
themselves, although they are used in some areas as fodder for camels, for fliel, and in providing stakes for fishing. 
These uses are probably decreasing in many countries in Une with increasing wealth in the region. Conversely 
many areas are increasingly threatened by pollution, especially oil pollution, which is widespread in many areas 
of the Gulf and the Straits of Hormuz. Landfill associated with urban and industrial development also threatens 
mangroves in many areas. 

Bahrain 

Land area 680 sq km 

Population (1995) 578,000 

GNP{1991) 7,150 US$ per capita 

Mean monthly temperature range 19-36°C 

Mean annual rainfall 130 mm 

Spring tidal amplitude 1.2 m 

Alternative estimate of mangrove area {Sheppard et a/.. 1 992) 1 sq km# 

Area of mangrove on the map 3 sq km 

Number of protected areas with mangrove 1 

Map reference 

Abbott (1995). Coral Reefs of Bahrain (Arabian Gulf). Unpublished report prepared for ReefBase and the World 
Conservation Monitoring Centre, including sketch map showing mangroves at 1 :350,000. 

Iran 

Land area 1 ,648,000 sq km 

Population (1995) 66,720,000 

GNP(1992) 2,080 US$ per capita 

Mean monthly temperature range (Abadan, northern Gulf) 1 2-36°C 

Mean annual rainfall (Abadan, northern Gulf) 204 mm 

Spnng tidal amplitude 1-2 m 

Alternative estimate of mangrove area (Khosravi and Motalebi, 1994) 207 sq km# 

Area of mangrove on the map 749 sq km 

Number of protected areas with mangrove 3 

Map reference 

Generalised data for the entire coastline were taken from Mobayen and Tregubo v (1 970) . Further details for the mangroves 
of Qeshm Island were added from an unreferenced high resolution map provided to WCMC by M. Khosravi, Department 
of the Environment. 

Mobayen, S. and Tregubov, V. (1970). Carte de la Vegetation Naturelle de I'lran. 1:2,500,000. Centre National Cartographique 
de riran. 

Oman 

Land area 2 1 2,460 sq km 

Population (1995) 1,822,000 

GNP (1992) 6,490 U5$ per capita 

Mean monthly temperature range (Muscat) 22-33°C 

Mean annual rainfall (Muscat) 99 mm 

Spnng tidal amplitude 1. 5-2. 5m 

Alternative estimate of mangrove area (Sheppard et al, 1992) 20 sq km# 

Area of mangrove on the map 34 sq km 

Number of protected areas with mangrove 1 

Map references 

Mangroves have been added to a 1:1,000,000 base map from lUCN (1986, 1988, 1989) which plots mangroves as points 
or polygons on maps at 1:312,500. These maps only cover approximately half of the coasdme between the Yemen border 
and the centre of Sawqirah Bay and from Ras ad Daffah to Sarimah. 

lUCN (1986). Oman Coastal Zone Management Plan: Greater Capital Area. Prepared for Ministry of Commerce and Industry, 

Muscat, Oman. lUCN, Gland, Switzerland. 78 pp. 
lUCN (1988). Oman Coastal Zone Management Plan: Quriyat to Ra's al Hadd. Prepared for Ministry of Commerce and 

Industry, Muscat, Oman. IIJCN, Gland, Switzerland. 57 pp. 
lUCN (1989). Oman Coastal Zone Management Plan: Dhqfar: Volume 2: Resource Atlas. Prepared for Mimstry of Commerce 

and Industry, Muscat, Oman. lUCN, Gland, Switzerland. 41 pp. 



160 World Mangrove Atlas 

Qatar 

Land area 1 1,000 sq km 

Population (1995) 490,000 

GNP(1991) 1 3,380 U5$ per capita 

Mean monthly temperature range 17-37°C 

Mean annual rainfall 62 mm 
Alternative estimate of mangrove area (Sheppard ef a/, 1992) <5 sq km# 

Area of mangrove on the map No data 

Number of protected areas with mangrove 

Map reference 

No data 

United Arab Emirates 

Land area 83,600 sq km 

Population (1995) 1,785,000 

GNP(1991) 20,200 US$ per capita 

Mean monthly temperature range (Dubai) 2342°C 

Mean annual rainfall (Dubai) 60 mm 

Alternative estimate of mangrove area (Khan, 1982) 30 sq km# 

Area of mangrove on the map No data 

Number of protected areas with mangrove 

Map reference 

No data 

Indian Ocean Islands Maps 9.2 and 9.3 

There are a number of small islands scattered throughout the Indian Ocean. Notable among these are the British 
Indian Ocean Territory (UK), the Comoros, the Maldives, Mauritius, Mayotte (France), Reunion (France) and 
the Seychelles. With the exception of the Seychelles and Mayotte, mangroves are not well developed in any of 
these islands and they are not recorded from Reunion. There is also very little documentation describing the 
mangroves in these countries. In Mauritius there are some scattered mangrove thickets and on Rodrigues a few 
scattered bushes are found near Mathurin Bay. Despite the large number of islands in the Maldives (over 1 ,000) 
none are very large in total area, and there are no rivers or freshwater bodies. The commonest types of mangrove 
formation in these islands are closed communities in brackish lagoons, often only connected to the sea by 
underground links. The largest and most diverse stands occur on the northernmost atoUs, and there is some 
cultivation and management, particularly of Bruguiera. This is an economically important species, providing 
timber particularly for boat-building. Only two species have been recorded from the Chagos Archipelago 
(British Indian Ocean Territory), and there is a small stand oiLumnitzera racemosa on Eagle Island on the Chagos 
Bank. The only significant stands of mangroves in the Comoros are a single stand on the southeast of Grande 
Comore and a few small areas on the southern shore of Moheli. The mangroves of Mayotte are well developed, 
probably as a result of the shelter provided by the barrier reef which encircles the island. Finally, in the Seychelles, 
fringing coastal communities are found on the coasts of Mahe, Curieuse, Praslin, La Digue and Silhouette and 
there are some fairly large areas in the lagoons of Aldabra and Cosmoledo, with most of the species found in 
the region being represented. 

British Indian Ocean Territory 

Land area 60 sq km 

Population (1995) Military and administrative 

personnel only (about 3,000) 
Mean annual rainfall 3,700 mm 

Map reference 

No data 



East Africa and the Middle East 



161 



Comoros 



Land area 

Population (1995) 

GNP(1992) 

Mean nnonthly temperature range 

Mean annual rainfall 

Alternative estimate of mangrove area 

Area of mangrove on the map 

Number of protected areas with mangrove 



2,230 sq km 

653,000 

510 US$ per capita 

22-28°C 

2,000 mm 

No information 

26 sq km# 





Map reference 

UK Hydrographic Office (1978). Comoros Islands. 1:300,000. British Admiralty Chart 563. 

Maldives 



Land area 

Population (1990) 

GNP(1990?) 

Average temperature range (daily) 

Mean annual rainfall 

Spring tidal amplitude 

Alternative estimate of mangrove area 

Area of mangrove on the map 

Number of protected areas with mangrove 



Map reference 

No data 

Mauritius 



Land area 

Population (1995) 

GNP(1992) 

Mean monthly temperature range 

Mean annual rainfall 

Alternative estimate of mangrove area 

Area of mangrove on the map 

Number of protected areas with mangrove 



Map reference 

No data 

Mayotte 



Land area 

Population (1991) 

Alternative estimate of mangrove area 

Area of mangrove on the map 

Number of protected areas with mangrove 



298 sq km 

213,215 

436 US$ per capita 

26-30°C 

1,500 mm 

0.9 m 

No information 

No data 





2,040 sq km 

1,130,000 

2,740 US$ per capita 

23-27°C 

1 ,000 mm 

No information 

No data 





373 sq km 

85,000 

No information 

10 sq km# 





Map reference 

Mangroves were estimated from a base map from a source at approximately 1:250,000 taken from Frazier (1985). 
Frazier, J. (1 985) . Marine Turtles in the Comoros Archipelago. North Holland Publishing Company, Amsterdam, The Netherlands. 



Seychelles 



Land area 

Population (1995) 

GNP(1992) 

Mean monthly temperature range (Victoria) 

Mean annual rainfall (Victona) 

Alternative estimate of mangrove area 

Area of mangrove on the map 

Number of protected areas with mangrove 



280 sq km 

74,000 

5,450 US$ per capita 

25-27°C 

2,375 mm 

No information 

29 sq km# 

4 



Map references 

Mangroves ftjr most islands have been prepared from a D.O.S. (1978) six-map series, themselves compiled from air 
photography, June 1960. Vegetation data for Aldabra were annotated onto these maps by R.N. Jenkin. 



i62 World Mangrove Atlas 

D.O.S. (1978). Aldahra Island East. 1:25,000 Series Y852 Pepartment of Overseas Surveys 304P) Ed.3. 
D.O.S. (1978). Aldahra Island West. 1:25,000 Series Y852 Pepartment of Overseas Surveys 304P) Ed.3. 
D.O.S. (1978). Farquhar Croup. 1:25,000 Series 304P Ed. 1-Department of Overseas Surveys. 
D.O.S. (1979). Cosmoledo Group. 1:25,000 Series 304? Ed. l-Department of Overseas Surveys. 
D.O.S. (1993). Providence Croup (North). 1:25,000 Series 304P Ed.3-OS. 
D.O.S. (1993). Providence Group (South). 1:25,000 Series 304P Ed.3-OS. 

Red Sea and Gulf of Aden Map 9.1 

The Red Sea and Gulf of Aden represent a continuous geological feature, which is an oceanic-type rift system 
separating the African and Arabian continental plates. Countries bordering this region include: Djibouti, Egypt, 
Eritrea, Israel (no mangroves) , Jordan (no mangroves), Somalia, Sudan and Yemen (including Socotra Island). 
There has been little research into the mangroves of most of the countries in the region, although the mangroves 
of the Saudi Arabian coast have been well surveyed and preliminary work is now under way in Eritrea and 
other countries. The coasthnes are arid to hyper-arid and there is no permanent freshwater input into the sea. 
Four mangrove species have been recorded, /Ificertttia marina, Ceriops tagal, Bruguiera gymnorrhiza and Rhizophora 
mucronata. Avicennia marina is the best adapted to the harsh environmental conditions. While positive historical 
records exist, there is some question as to the continued existence of both Ceriops tagal and, more especially, 
Bruguiera gymnorrhiza in the region. Rhizophora mucronata is found at a number of sites but is not recorded from 
the northernmost parts of the Red Sea. High salinity may limit mangrove occurrence in all areas, while in 
northern areas low temperatures may further restrict development. In most areas, mangroves are found in 
sheltered embayments and behind reefs. When mangroves are found behind the reef-flat in many areas there is 
often only a thin veneer of substrate overlying fossil reef structures and this may further contribute to their 
reduced size and restricted distribution. The best developed stands occur in the southern parts of the Red Sea. 
These are often associated with 'soft-bottom' substrates in sheltered embayments. These southern areas are 
further characterised by a wider shelf area, better protected shorehnes, and higher nutrient concentrations. In 
such areas stands of 100-500 m width are found, with the tallest trees reaching 5-7 m in height. There is little 
information describing the mangrove communities along the Yemen coast on the Gulf of Aden, although 
mangroves are well developed in a number of areas along this sector of the Somali coast. Small mangrove 
communities have been reported from the Yemeni island of Socotra, while the Indian Ocean coastline of Somalia 
(not strictly within the geographic hmits described above) has some significant areas of mangrove, particularly 
associated with estuaries close to the Kenyan border. Lumnitzera racemosa and Sonneratia alba have been recorded 
from this area. 

In Saudi Arabia and several of the other countries of the region, the grazing of mangroves by camels has had 
a significant impact and is likely to continue or increase. Loss of mangrove areas has also occurred in Saudi 
Arabia due to coastal engineering and landfiU projects, together with poUution from urban and industrial areas. 
Localised impacts are also likely to occur as a result of the high sahnity and high temperature effluents associated 
with desalination plants. 

Djibouti 

Land area 23,200 sq km 

Total forest extent ( 1 990) 220 sq km 

Population (1995) 511,000 

Mean monthly temperature range 26-36°C 

Mean annual rainfall 130 mm 

Alternative estimate of mangrove area No information 

Area of mangrove on tfie map 1 sq km# 

Number of protected areas witfi mangrove 

Map reference 

Map based on 1985 Landsat MSS. 

Forgiarini, G. and Cesar, J. (1 987) . Vegetation et Ressources Pastorales. 1 :250,000. Institut d'Elevage et de Medecine Veterinaire 
des Pay Tropicaux, France. 



East Africa and the Middle East 163 

Egypt 

Land area 1,001,450 sq km 

Population (1995) 58,519,000 

GNP(1992) 630 US$ per capita 

Mean monthly temperature range (Ismailia, northern Red Sea) 1 3 29°C 

Mean annual rainfall (Ismailia, northern Red Sea) 37 mm 

Alternative estimate of mangrove area No information 

Area of mangrove on the map (861 sq km)# 

Number of protected areas with mangrove 2 

Map reference 

Data are of very low resolution and likely to be inaccurate, based on a regional sketch map in Sheppard ct al. (1992). 
Sheppard, C, Price, A. and Roberts, C. (1992). Marine Ecology of the Arabian Region: Patterns and Processes in Extreme Tropical 
Environments. Academic Press, London, UK. 

Eritrea 

Land area 93,579 sq km 

Population (1994) 3,530,000 

GNP(1993) 77 US$ per capita 

Mean monthly temperature range (Massawa) 26-34°C 

Mean annual rainfall (Massawa) 193 mm 

Alternative estimate of mangrove area No information 

Area of mangrove on the map (581 sq km)# 

Number of protected areas with mangrove 

Map reference 

There are no accurate published maps showing the distnbution of mangroves in Eritrea. Data were very kindly provided, 
annotated onto an approximately 1:1,000,000 base map using aerial photographs combined with detailed personal 
knowledge of the region, by Dr Chris Hillman, Mimstry of Marine Resources, Entrea and by Dr Liz Ross, Department 
of Earth Sciences, University of Oxford, UK. 

Saudi Arabia 

Land area 2,149,690 sq km 

Population ( 1 995) 1 7,608,000 

GNP(1992) 7,940 US$ per capita 

Mean monthly temperature range (Jeddah) 23-31°C 

Mean annual rainfall (Jeddah) 81mm 

Alternative estimate of mangrove area (Sheppard et al., 1992) 204 sq km 

Area of mangrove on the map 292 sq km# 

Number of protected areas with mangrove 3 

Map references 

Maps have been prepared for the Red Sea from lUCN/MEPA (1984,1985) unpubhshed reports with detailed data at 
1:250,000, and for the Gulf from MEPA (1987) maps which simply mark small linear sections of the coast as having 
mangrove (1:2,000,000). 
lUCN/MEPA (1984). Report on the Distribution of Habitats and Species in the Saudi Arabian Red Sea: Part 1. Saudi 

Arabia Marine Conservation Programme, Report No. 4. lUCN, Gland, Switzerland/Meteorology and Enviromnental 

Protection Adnunistration, Jeddah, Kingdom of Saudi Arabia. 123 pp., numerous tables, photos, maps. 
lUCN/MEPA (1985). Distribution of Habitats and Species along the Southern Red Sea Coast of Saudi Arabia. Saudi 

Arabia Marine Conservation Programme, Report No. 1 1 . lUCN, Gland, Switzerland/Meteorology and Enviromnental 

Protection Administration, Jeddah, Kingdom of Saudi Arabia. 61 pp., numerous tables, photos, maps, annexes. 
MEPA (1987). Arabian Gulf. Saudi Arabia: an assessment of biotopes and coastal zone management requirements for the Arabian 

Gulf MEPA Coastal and Marine Management Series. Technical Report No. 5, December 1987 (printed January 1992). 

Meteorology and Environmental Protection Administration, Jeddah, Kingdom of Saudi Arabia/IUCN, Gland, 

Switzerland. 248 pp. 



164 World Manq^rove Atlas 

Somalia 

Land area 637,660 sq km 

Total forest extent { 1 990) 7,540 sq km 

Population ( 1 995) 1 0, 1 73,000 

GNP(1990) 120 US$ per capita 

Mean monthly temperature range (Berbera) 24-36°C 

Mean annual rainfall (Berbera) 51 mm 

Alternative estimate of mangrove area No information 

Area of mangrove on the map (910 sq km)# 

Number of protected areas with mangrove 

Map reference 

Mangroves were annotated onto a 1:1,000,000 base map by R.H. Hughes, and are based on Hughes and Hughes (1992). 
Further small areas were added by Frani;:ois Blasco. 

Hughes, R.H. and Hughes, J.S. (1992). A Directory of African Wetlands. lUCN, Gland, Switzerlatid and Cambridge, 
UK/UNEP, Nairobi, Kenya/WCMC, Cambridge, UK. 820 pp. 

Sudan 

Land area 2,505,810 sq km 

Total forest extent (1990) 429,760 sq km 

Population (1995) 28,960,000 

GNP(1990) 400 U5$ per capita 

Mean monthly temperature range (Port Sudan) 23-34°C 

Mean annual rainfall (Port Sudan) 94 mm 

Alternative estimate of mangrove area No information 

Area of mangrove on the map (937 sq km)# 

Number of protected areas with mangrove 

Map reference 

Data are of very low resolution and likely to be inaccurate, based on a regional sketch map in Sheppard et al. (1992). 
Sheppard, C, Price, A. and Roberts, C. (1992). Marine Ecology of the Arabian Region: Patterns and Processes in Extreme Tropical 
Environments. Academic Press, London, UK. 

Yemen 

Land area 527,970 sq km 

Population (1995) 13,897,000 

GNP(1991) 520 US$ per capita 

Mean monthly temperature range (Aden) 24-32°C 

Mean annual rainfall (coastal areas) 46 mm 

Alternative estimate of mangrove area No information 

Area of mangrove on the map 81 sq km# 

Number of protected areas with mangrove 

Map references 

Data for the former Yemen Arab RepubUc (North Yemen) obtained from lUCN (1987), which comprises four maps 
covering the coast at 1 :500,000, based on field surveys. A small area for the coast of former South Yemen was added from 
Sheppard et al. (1992) and areas were annotated for the Island of Socotra from RGS (1978). This is reported to be the 
most accurate data available for the island and has a symbol which describes 'coastal marsh and mangrove'. 

lUCN (1987). The Distribution of Habitats and Species along the YAR Coastline. lUCN, The World Conservation Umon, 

Gland, Switzerland. 
RGS (1978). Socotra. 1:125,000. Royal Geographical Society, London. 
Sheppard, C, Price, A. and Roberts, C. (1992). Marine Ecology of the Arabian Region: Patterns and Processes in Extreme Tropical 

Environments. Academic Press, London, UK. 



East Africa and the Middle East 165 

Kenya Map 9.2 

Land area 580,370 sq km 

Total forest extent ( 1 990) 1 1 ,870 sq km 

Population (1995) 27,885,000 

GNP(1992) 330 US$ per capita 

Mean monthly temperature range 21-32°C 

Average rainfall range (Lamu) 750-1,000 mm 

Average rainfall range (Mombasa) 1,000-1,500 mm 

Spring tidal amplitude 3 5 m 

Alternative estimate of mangrove area (Ruwa, 1993) 530 sq km# 

Area of mangrove on the map 961 sq km 

Number of protected areas with mangrove 3 

The coastline of Kenya is senii-and, becoming more humid to the south. Mangroves are well developed in 
many areas, being particularly concentrated m creeks, bays and estuaries. There are only two large permanent 
rivers reaching the coast, the Tana and the Sabaki (Galana), both of which support mangroves. There are also a 
large number of seasonal rivers, and in many of these there is an associated ground water discharge which 
reduces salinities even when the rivers themselves are dry. To the north of the country, mangroves are well 
developed in the lee of several islands, notably Lamu, and on the corresponding sheltered coasthnes. In the far 
south, offshore islands and fringing reefs also provide a more protected coasdine suitable for the development 
of mangroves. Two basic formations have been described: fringe communities which do not show patterns of 
zonation; and creek mangrove formations found in low energy, more sheltered environments, which are often 
larger in aerial extent and may show zonation patterns. 

There is a long tradition of using of mangrove areas in Kenya. Fishing villages are typically located close to 
mangrove areas, perhaps because of the freshwater associated with adjacent shallow water-tables. Mangrove 
timber has traditionally been used for building of houses, furniture and boats. The mangroves have been also 
used for fuel and used, to a lesser extent, for honey production, while some fishing for crabs and oysters takes 
place. The traditional export of mangrove timber from Lamu and elsewhere to the Middle East has been 
forbidden by law, in an effort to reduce degradation and loss of mangroves. Estabhshment of salt pans and shrimp 
farms has led to the loss of small areas of mangrove. Wider scale degradation is likely to be caused by pollution 
from sewage effluents, the dumping of solid waste, and increasing saHnity as a result of the damming of rivers. 
The areas around Mombasa are further likely to be threatened by the development of the port and the risk of 
oil pollution. An oil spill in 1988 caused the loss of a considerable area of mangroves. 

Map reference 

Delsol.J.P. (1995). A Vegetation Map of Kenya. 1:1,000,000. Institut de la Carte Internanonale de la Vegetation, Toulouse, 
France. 



Madagascar Map 9.3 

Land area 587,040 sq km 

Total forest extent ( 1 990) 1 57,820 sq km 

Population (1995) 14,155,000 

GNP(1992) 230 U5$ per capita 

Mean annual rainfall range (Antseranana to River Manambolo) 950 2,000 mm 

Mean annual rainfall range (River Manambolo to River Mangoky) 500-900 mm 

Mean annual rainfall (River Mangoky to Cap Sainte Marie) 350 mm 

Spring tidal amplitude (west coast) 3 5 m 

Spring tidal amplitude (east coast) 0,75 m 

Alternative estimate of mangrove area (Marguerite, 1993) 3,270 sq km 

Area of mangrove on the map 3,403 sq km# 

Number of protected areas with mangrove 1 

In Madagascar, mangroves are almost entirely limited to the western coast facing the Mozambique channel, 
with only about 50 sq km of mangroves found along the eastern coast. The most significant mangrove stands 
are found in the northwest, at Mahajamba Bay, Bombetoka, South Mahavavy and Salala, and Maintirano, where 
the climate is semi-humid. Many of the stands are in sheltered river mouth areas, but Unear formations also 
occur in Mahavavy and Maintirano. Trees in this area may reach 20 m in height. Further to the southwest, the 
climate becomes more and, with a dry season of seven to nine months in duration, and extensive mangrove 
areas are less common. In this region, wide areas of bare sahne soils are often found behind the mangroves, 
known as 'tannes' or 'sira-sira'. Typically, trees in this area rarely reach 6 m in height.Human uses of the mangroves 



1 66 World Mangrove A tlas 

are limited in extent, although may be considerable in the areas around Tulear and Mahajanga, particularly for 
charcoal and timber. Fishing occurs in mangrove areas, particularly for prawns, but there has been no clearance 
for aquaculture. This lack of human disturbance can be largely related to the relatively low population densities 
in most mangrove areas, combined with the availabihty of other timber and fuelwood sources. Demographic 
trends suggest that pressure on mangrove areas could increase considerably in the future. The generally quoted 
area of mangroves (3,270 sq km) is based on a 1966 estimate, but it has been suggested that the total area may 
not have decreased, or may have even increased since that time, resulting from the colonisation of rapidly 
advancing alluvial deposits. 

Map references 

Main source was Faramalala Miadana Harisoa (1996), with minor corrections from CI/DEF/CNRE/FTM (n.d.). Both 
these are drawn from the same source, 1972-79 Landsat imagery. The fonner appears to give higher precision, but the 
latter includes some additional mangrove areas m the far north of the country. 

CI/DEF/CNRE/FTM (n.d.). Formations Vcii-taks ct Momainc Forestier National de Madagascar 1:1,000,000. Conservation 
InternaQonale/Direcrion des Eaux ct Forets/Centre National de Recherches sur I'Environnement/ Foiben-Taosarintanin' I 
Madagasikara. 

Faramalala Miadana Harisoa (1996). Carte des Formations Vegetates de Madaj^ascar. 1:1,000,000, 3 sheets. I.C.I.V, Toulouse, 
France. 



Mozambique Map 9.3 

Land area 801,590 sq km 

Total forest extent ( 1 990) 1 73,290 sq km 

Population ( 1 995) 1 6,359,000 

GNP(1992) 60 US$ per capita 

Mean monthly temperature range (Beira) 21-28°C 

Average rainfall range 800-1,500 mm 

Spnng tidal amplitude (Beira) 5.6 m 

Alternative estimate of mangrove area (Hughes and Hughes, 1992) 850-1,000 sq km# 

Area of mangrove on the map 3,459 sq km 

Number of protected areas with mangrove 5 

Mangroves are widespread and are located in all river mouths and in many sheltered bays and lagoons, although 
they are less widespread towards the south of the country. The coastHne is the wettest part of the country, 
although most areas receive only about 800-900 mm ram per year with some pockets receiving up to 1,400 mm. 
The coast is warmed by the southward flowing Mozambique current. The full diversity of mangrove species 
from the region is found in the country, although some of these have their southern hmits in Mozambique. In 
the far north mangroves form a near-continuous narrow strip along the many sheltered bays and river mouths. 
Between Mozambique and the Zambezi Delta, the sheltering fringing reef disappears, but mangroves are found 
in the many small deltas all along this stretch where aUuvial deposits are considerable. These rivers may be tidal 
for many kilometres upstream and the mangrove communities typically grade into swamp forest. Mangrove 
swamps are extensive throughout the lower delta of the Zambezi, along the deltaic coast that extends to Beira 
and in the many river mouths and sheltered bays to the south. Flonstically, the mangroves between Beira and 
the Save River are probably the best developed in the country, and perhaps on the entire eastern seaboard of 
Africa. In many areas they reach inland for 5-15 km and extend up to 50 km inland along the Save. In these 
areas, and in the Zambezi Delta, the canopy may reach 25 m or even 30 m in height. Northward pointing spits, 
formed by eddies from the southward flowing offshore current, protect a number of mangrove-fiUed bays, 
including the 200 sq km mangrove forest behind the spit of Sao Sebastiao. In the far south of the country 
mangroves are not well developed except along the southern shore of Maputo Bay. 

Most areas of mangroves have been utilised by man, although this is most pronounced closer to centres of 
high population density, notably in the north of the country and close to ports. Trees, especially Rhizophora 
mucronata, are widely used for timber, firewood and charcoal. Traditional Arab trade along the East African coast 
was mosdy with Kenya and Tanzania, but also occurred as far south as Beira. There is some artisanal fishing in 
mangroves and permanent fish traps are a feature of many areas. The mangrove area given by Hughes and 
Hughes (1992) of 850-1,000 sq km is thought to be conservative. 

Map reference 

Mimsteno da Agricultura (1980). Mapa Florestal. 1:2,000,000 (reduced from 1:1,000,000). Projecto UNDP-FAO 
MOZ/76/007. Ministerio da Agricultura, Dto Florestal e de Fauna Bravia, Republica Popular de Mofambique. 



East Africa and the Middle East 167 

South Africa Map 9.3 

Land area 1.221,040 sq km 

Population (1995) 42,741,000 

GNP(1992) 2,670 US$ per capita 

Mean monthly temperature range (Durban) 1 7-24°C 

Average rainfall range (St Lucia) 1 .200 mm 

Spring tidal amplitude 0.75-1.5 m 

Alternative estimate of mangrove area (lUCN, 1983) 1 1 sq km# 

Area of mangrove on the map (335 sq km) 

Number of protected areas with mangrove 8 

Due to the warming effect of the Mozambique current, mangroves occur on the east coast of Afnca as far south 
as 32° 59' latitude and, therefore, along the northeast coast of South Africa. On the west coast of Africa, the 
southernmost extent of mangroves is m Angola, nearly 20 degrees of latitude further north than on the east 
coast. In the south, mangroves are monospecific stands of Avicennia marina, with the southernmost stand being 
in the Nahoon River mouth just north of East London. Bru^uiera i^ymmmhiza is found as far south as 32° 14' 
and Rhizophora mucronata ]o\ns the assemblage soon after. The Mngazana estuary is the first significant stand of 
mangroves, with about 1 .6 sq km of peripheral mangrove and saltmarsh communities. Further north, most 
mangrove areas are much smaller, while the once extensive swamps around Durban have been almost entirely 
cleared. To the north, mangroves are found in the St Lucia estuary, which connects to Lake St Lucia, the Mfolozi 
River mouth and around the lower tidal basin and lake system of Kosi Bay At this latter site two further species 
are found: Ccriops tagal and Lumnitzcra racemosa. Coastal development has destroyed the mangroves in some areas 
but they have legal protection within a number of protected areas. 

Map reference 

Small areas have been annotated onto a base map, using the textual descriptions of these locations from Hughes and 
Hughes (1992). While these may be indicative of mangrove locations they should not be regarded as providing a fiill or 
accurate areal coverage. 

Hughes, R.H. and Hughes, J. S. (1992). A Directory of African Wetlands. lUCN, Gland, Switzerland and Cambridge, 
UK/UNEP, Nairobi, Kenya/WCMC, Cambridge, UK. 820 pp. 

Tanzania Map 9.2 

Land area 945,090 sq km 

Total forest extent (1990) 429,760 sq km 

Population (1995) 30,742,000 

GNP ( 1 992) 1 1 US$ per capita 

Mean monthly temperature range (Dar es Salaam) 23 28°C 

Mean annual rainfall (Dar es Salaam) 1 ,064 mm 

Spnng tidal amplitude 3 2 m 

Alternative estimate of mangrove area (Semesi, 1 993) 1 , 1 55 sq km# 

Area of mangrove on the map 2,456 sq km 

Number of protected areas with mangrove 6 

There is a long history of the use of mangroves in Tanzania, dating back to at least the nmth century when they 
were used as a major rimber supply to the non-forested countries to the north, particularly on the Arabian 
Peninsula. Mangroves remain relatively widespread despite the exploitation. The largest mangrove area is on 
the Rufiji River Delta, but other large areas are found at Tanga, Kilwa and the estuaries of Ruvu, Wami, Pangani 
and Ruvuma Rivers. Most mangrove areas remain heavily exploited for timber and firewood and in many areas 
trees fail to reach their full stature. Uses include timber for fences, houses, boats, fish traps and fuelwood. Some 
poles are cut for export and the local markets, though much of this is illegal. Fishing, and particularly prawn 
fishing in mangrove areas is very important. In the Rufiji Delta, some areas have been cleared for rice cultivation. 
The remainder of the delta is now protected although it is still under considerable pressure from local 
populadons, despite the observed dechning yields on the existing farms. Further areas have been cleared for the 
construction of salt pans. The importance of mangroves to Tanzania has been recognised and all mangrove areas 
are legally protected. The key to their protection lies in the wise management and use of mangrove areas, and 
in the enforcement of existing regulations. 

Map reference 

Areas taken from summary map of a more detailed mangrove forest inventory supported by NORAD, based on aenal 
photography taken in 1988/9. 

Ministry of Lands (1990). Sheet Index Map: the Mangrove Forest Reserves of Tanzania. 1:1,000,000. Mimstry of Lands, Natural 
Resources and Tourism, Forest and Beekeeping Division, Dar-es-Salaam, Tanzania. 



168 World Mangrove Atlas 

Sources 

Bellamy, D. (1979). Half of Paradise. Cassel Ltd., London, UK. 192 pp. 

CEC (1992). Man^^roves of Africa and Madafiascar Comniission of the European Communities, Directorate General for 

Development, Luxembourg. 273 pp. 
Diop, E.S. (1993). Conservation and Sustainable Utilization ofManf>roi>e Forests in Latin America and Africa Regions. Part II - 

Africa. Mangrove Ecosystems Techmcal Reports - 3. International Society for Mangrove Ecosystems, Okinawa.Japan. 

262 pp. 
Hughes, R.H. and Hughes, J. S. (1992). A Directory of African Wetlands. lUCN - World Conservation Umon, Umted 

Nations Environment Programme and World Conservation Monitoring Centre, Gland, Switzerland; Nairobi, Kenya; 

and Cambridge, UK. 820 pp. 
ISME (1994). Proceedings of the VII Pacific Inter-Congress Mangrove Session, Mangrove Session, Okinawa, fapan 1-2 July, 1993. 

Mangrove Ecosystems Proceedings - 3. International Society for Mangrove Ecosystems, Okinawa, Japan. 120 pp. 
lUCN (1983). Global Status of Mangrove Ecosystems. Commission on Ecology Papers No. 3. Saenger, P., Hegerl.E.J. and 

Davie,J.D.S. (Eds). International Umon for Conservation of Nature and Natural Resources, Gland, Switzerland. 

88 pp. 
Khan, M.I. R. (1982). Status of mangrove forests in the Urated Arab Emirates. Bulletin of the Emirates Natural History 

Croup (Abu Dhabi) 17: 15-17. 
Khosravi, M. and Motalebi, S.A. (1994). Mangrove studies project in the Khuran Strait. In: Indus Delta Biosphere Reserve: 

Workshop Report. lUCN - World Conservation Union, Gland, Switzerland, pp. 57-60. 
Marguerite, R.V. (1993). Mangroves of Madagascar. In: Cotiservation and Sustainable Utilization of Mangrove Forests in Latin 

America and Africa Regions. Part II - AJrica. Diop, E.S. (Ed.). Mangrove Ecosystems Technical Reports. International 

Society for Mangrove Ecosystems, Okinawa, Japan, pp. 245-260. 
MEPA (1987). Arabian Gulf. Saudi Arabia: an assessment ofbiotopes and coastal zone management requirements for the Arabian 

Gulf. MEPA Coastal and Marine Management Series. Technical Report No. 5, December 1987 (printed January 

1992). Meteorology and Enviromnental Protection Administration, Jeddah, Kingdom of Saudi Arabia/IUCN, Gland, 

Switzerland. 248 pp. 
NIO (1991). Scientific report on status of atoll mangroves from the Republic of Maldives. National Institute of 

Oceanography, Ministry of External Affairs, New Delhi, India. 
Ruwa, R.K. (1993). Mangroves of Kenya. In: Conservation and Sustainable Utilization of Mangrove Forests in Latin America 

and Africa Regions. Part II - Africa. Diop, E.S. (Ed.). Mangrove Ecosystems Technical Reports. International Society for 

Mangrove Ecosystems, Okinawa, Japan, pp. 227-243. 
Sahn, R.V. (1978). Conservation of marine resources in Seychelles: report on current status and future management. 

Report for lUCN. 41 pp. 
Sayer.J.A., Harcourt, C.S. and Collins, N.M. (1992). T/ie Conservation Atlas of Tropical Forests: Africa. Macnullan Press Ltd, 

London, UK. 256 pp. 
Semesi, A.K. (1993). Mangrove ecosystems of Tanzania. In: Conservation and Sustainable UtiUzation of Mangrove Forests in 

Latin America and Africa Regions. Part II - Africa. Diop, E.S. (Ed.) . Mangrove Ecosystems Technical Reports. 

International Society for Mangrove Ecosystems, Okinawa, Japan, pp. 211-225. 
Sheppard, C, Price, A. and Roberts, C. (1992). Marine Ecology of the Arabian Region: Patterns and Processes in Extreme 

Tropical Environments. Academic Press, London, UK. 359 pp. 
UNEP (1986). Enviromnental Problems of the Marine and Coastal Area of Maldives: National Report. UNEP 

Regional Seas Reports and Studies - 76. United Nations Enviromnent Programme, Nairobi, Kenya. 31 pp. 



East Africa and the Middle East 



U9 




no 



World Mangrove Atlas 




Map 9.2 East Africa: Somalia to Tanzania 



East Africa and the Middle East 



171 





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Index 



Note: Page numbers referring to maps are given in bold 



Abaco Island 124 

Abidjan 155 

Aboriginals (Australian) 
84 

Abu Dhabi 169 

Acanthus 

cbracteatus 44, 83 

ilidfolius 44, 83 

Acapulco 122 

Accra 155 

accuracy 21 

Acome, Rio 107 

Acrostichum 

aureum 44,83,95,130, 
158 

danaeifolium 95 

speciosum 44, 83 
Addis Ababa 169 
AdduAtoU 170 
Adelaide 91 
Adelaide River 90 
Aden 169 

Gulf of 162-164, 169 
Admiralty Islands 93 
Aegialitis 28 

annulata 28,31,44,83 

rotundifolia 28,31,44 

Aegkeras 28 

corniculatum 28, 31, 44, 
83 

Jloridum 28,31,44 

aerial photography 18,48 

Agenda 21 12 

Agua Brava, Laguna 113, 
122 

Aklins Island 96, 124 

AldabraAtoU 160,170 

Alligator River 

East 90 



South 90 

Amanii-O 77 

Amapa 98 

Ainazon River 128 

Ambryin 92 

American Samoa 83, 85 

Americas, The 94-127 

Andaman and Nicobar 
Islands 53,74 

Andaman Islands 75 

Andaman Sea 75 

Andros Island 96, 124 

Angola 130,156 

Anguilla 109,110,125 

Antananarivo 171 

Antigua 109,110,125 

Antsiranana 171 

Aoba 92 

aquaculture 1 1 , 67 

Arabian Gulf 158,169 

Arabian Sea 74 

Arafura Sea 81 

Archer River 91 

AriAtoU 170 

aridity 29 

Aruba 95, 96, 127 

Ashburton River 90 

Asmara 169 

Assinie 133, 155 

Asta Lagoon 113 

Adantic Ocean 
124-126, 128, 
154-156 

Auckland 92 

Australasia 82-93 

Australia 24,83,84 

Eastern 91 

Western 90 
Avkennia 

alba 34,44,83 



bkolor 28,37,95 
gcrmimms 38,95,130 
mtc^ra 28,36,83 
marina 32,44,83,158 
officinalis 34,44,83 
rumphiana 28, 35, 44, 83 
schaucriana 28, 37, 95 



B 

Bahamas 95,96,124 

Bahia de Amatique 123 

Bahia de Samana 100, 
124 

Bahrain 158,159,169 

Ball 80 

Baloclustan 21,63-65 

Balsas, Rio 122 

Banc d'Arguin National 
Park 145, 148 

Banda Sea 81 

Bandar Seri Begawan 80 

Bangka 79 

Bangkok 75 

Bangladesh 44,45,47,75 

Banjul 139,154 

Barbados 109,110,125 

Barbuda 109,110,125 

Barra de Santiago 102 

Barranquilla 127 

Barrow Island 90 

Basse-Terre 

(Guadeloupe) 125 

Basseterre (St Kitts) 125 

Batangas 78 

Bay of Bengal 21,47,74, 

75 
Bay of Plenty 92 
Beira 166,171 
Belait River 46,80 



Belem 128 

Belize 95,97,122,123 
Belmopan 122, 123 
Benguela 156 
Bemn 130, 131,155 
Benin River 145 
Berbera 169,170 
Bermuda 95,97,124 
Bight of Aklins 96 
Bigi Pan 116 
Bijagos Archipelago 154 
Bintum Bay 54, 81 
Biodiversity Convention 
12 

Bioko 155,156 

Biscayne Bay 117,124 

Bismarck Archipelago 93 

Bismarck Sea 93 

Bissau 154 

BocasdelToro 114,127 

Bogata 127 

Bohol 61,78 

Bombay 53,74 

Bombetoka 165, 171 

Bonaire 96,127 

Bonaparte Archipelago 
90 

Borneo 80 

Bougainville 93 

Brahmaputra, Delta 45, 

47-51 

Brasilia 128 

Brazil 24, 95, 98, 126, 

128 
Brazzaville 156 
Bridgetown 125 
Brisbane 91 
British Indian Ocean 

Territory 158,160, 

170 



174 



World Mangrove Atlas 



British Virgin Islands 
109,110 

Broome 90 

Bruguiera 

cylindrua 44, «3, 15H 

exaristata 44, 83 

gyfriorrhiza 29,44,83, 
158 

hainesii 28,44,83 
parvijlora 29,44,83 
scxangula 29,34,44,83 
Brunei Darussalam 44, 
46,80 

Brunei River 46,80 
BubaliPond 96 
Buenaventura 99, 127 
Burkina Faso 155 
Burma 75 
Burn 81 



Ca Mau Peninsula 71, 
75,76 

Cabmda (Angola) 130, 
147,156 

Cabo Corrientes 99, 127 

Cacheu River 154 

CaicosBank 117,124 

Caicos Islands 117 

Calabar River 145 

Calamian Group 78 

Calcutta 74 

Camaguey, Archipelago 
de 124 

Cambodia 44,46,75,76 

Cameroon 130,132,156 

Campeche 113 

Camptostemon 28 
philippincnse 28, 44 
schultzii 28,44,83 

Canberra 91 

Cap Haitien 124 

Cap Tiinirist 154 

Cape Lopez 134, 137, 
156 

Cape Lopez Bay 138 

Cape Melville 91 

Cape Pahnas 144, 155 

Cape Santa Maria 130, 
171 

Cape Three Points 1 43 , 
155 



CapeTimirist 145 
Cape Verde 154 
Caracas 127 
Caratasca, Laguna de 
108,123 

Caribbean 94-127 
Caribbean Sea 124, 125, 
127 

Carom Swamp 116,126 

Carpentaria, Gulf of 91 

Casamance River 146, 
154 

Castries 125 

Cat Island 124 

Cauvery Delta 53, 
55-57, 74 

Cavally River 133,155 

Cayapas Estuary 101,127 

Cayenne 126 

Cayman Brae 98 

Cayman Islands 95, 
98-99, 124 

Cebu 61,78 

Celebes Sea 81 

Central America 
94-127,123 
Central Province (Papua 

New Guinea) 88 
Cerani 81 
Ccriops 
australis 83 
decandra 44, 83 
ta<ial 44,83, 158 

ChagosArchipelago 160, 
170 

ChagosBank 160,170 

Chan-Yun-Cliia Reserve 
52 

Chandeleur Islands 117, 
122 

Charlotte AmaUe 125 

Chetumal 122 

China 44,52,76,77 

Eastern 77 

Southern 76 

Chiriqui, Golfo de 114, 
127 

Chocon.Rio 107 

Choiseul 93 

Chokoria Sundarbans 

45,75 
Cobourg 90 

Codrington Lagoon 
109,125 



Colombia 95,99,127 

Colombo 74 

Como River 134,156 

Comoros 158,160,161, 
170,171 

Conakry 154 

Congo 130, 132, 156 

Conkouati Lagoon 132, 
156 

Conocarpus crcctiis 39,95, 
130 

Coppename Monding 
116 

Coral Sea 91,93 

Cosmoledo 160 

Costa Rica 95,99-100, 
123 

Coted'lvoire 130,133, 
155 

Couffo River 155 

country tables, key to 25 

Crocodylus rhomhifcr 100 

Crooked Island 96, 124 

Cross River 145, 155 

Cuanza River 156 

Cuba 95, 100, 124 

National Forestry Policy 
100 

Cuban crocodile 100 

Curasao 96, 127 

Curieuse 160 

Curtis Island 91 

cyclones 43, 45 

Cynomctra iripa 44, 83 

D 

D'Entrecasteaux Islands 
93 

Dagupan 78 

Dahlak Archipelago 169 

Dakar 154 

Dampier 90 

DanKunKu Island 139 

Dar es Salaam 170 

Darwin 90 

Dhaka 74,75 

Diama dam 145 

Diego Garcia 170 

Diombos River 148 

Diospyros ferrea 83 

Djibouti 158,162,169 

Doha 169 



Dolichandrone spathacea 
44,83 

Domimca 109,110,125 

Domimcan Repubhc 95, 
100-101,124 

Douala 156 

Drysdale River 90 

Durack River 90 

Durban 167,171 



East Africa 157-171 

East China Sea 77 

East London 171 

Ecuador 95,101-102, 
127 

Egypt 158,163,169 

El Salvador 95,102,123 

Elephant Island 139 

Eluthera 124 

endeiTiism 28 

Epi 92 

Equatorial Guinea 130, 
133,156 

Eritrea 158,163,169 

Espiritu Santo 92 

EsteroReal 113,123 

Ethiopia 169 

Eucla 90 

Eudocimus ruber 116 

European Radar SateUite 
(ERS) 18,103,105 

Excoecaria 

agalhcha 44,83,158 

indka 28,36,44 

opalis 28, 36 
Exuma Cays 124 



FadifFolu Atoll 170 

Falmouth 124 

Farasan Islands 169 

Federated States of 
Micronesia 83,85, 
92 

FeUduAtoU 170 

Fiji 83,85,86,92 

Flores 80,81 

Florida 117,124 

Everglades 117,124 



Index 



175 



Everglades National 
Park 117 

Keys 124 
Fly River 88,93 
Fonesca, Golfo de 102, 
108,113,123 

Food and Agriculture 
Organization (FAO) 
12 

Fort-de-France 125 

Fortescue River 90 

fossil record 27 

Fraser Island 91 

Freetown 154 

French Guiana 21,95, 
102, 103-106, 126 

Fresco 133,155 



Gabon 21,130,134, 

135-138,156 
Gabon Estuary 135 
Galana River 170 

Gambia 21,130,134, 
139-142, 154 

Gambia River 154 

Gambian-German 

Forestry Project 139 

Ganges Delta 45,47-51, 
74 

Gawater Bay 63 

Geographical 

Information Systems 
(GIS) 16,20 

Georgetown (Gambia) 
154 

Georgetown (Guyana) 
126 

Ghana 130,143,155 

Godavari Delta 53, 74 

Gonaives 100,124 

Grand Bahama 96, 124 

Grand Bassam 133,155 

Grand Cayman 98, 124 

Central Mangrove 
Swamp 124 

Grand Cul-de-Sac 
Marin 125 

Grande Comore 160 

Grande, Rio 122 

Great Abaco 96 



Great Andaman 

Biosphere Reserve 
53 

Great Australian Bight 

84,91 

Great Barrier Reef 84 

Great Inagua 96, 124 

Greater Antilles 124 

Grenada 109,111,125 

Grenadines 109,112,125 

Groote Eylandt 91 

ground surveying 15 

ground-truthing 17 

Guadalcanal 93 

Guadeloupe 109,111, 
125 

Guam 83,86,92 

Guangzhou 76 

Guatemala 95, 107,122, 
123 

Guayaquil Gulf 101,127 

Guayas River 127 

Guinea 130,143,154, 
155 

Guinea-Bissau 130,144, 
154 

Gulf, The sec Arabian 
Gulf 

Guyana 95,103,107,126 



H 

Haddummati AtoU 170 
Hainan 52, 76 
Haiti 100-101,124 
Hamilton 124 
Hanoi 75, 76 
Hatia Island 48 
Havana 124 
Helmahera 81 
Heritiera 

fames 28, 36, 44 

globosa 44 

littoralis 44,83,158 

Hinchinbrook Island 91 

Hispamola 95, 100 

Honduras 95, 108, 122, 
123 

Gulf of 123 

Hong Kong 44,52,76, 
77 

Homara 92,93 



Houston 122 

Hue 75,76 

Hurghada 169 

hybridisation 28 

hydrographic charts 14, 
15 



I 

le 77 

UeTidra 129,154 

image processing 16 

India 44,47,53,55,74 

National Committee on 
Wedands, Mangroves 
and Coral Reefs 53 

National Mangrove 
Committee 53 

Indian Ocean 74,79,90, 
160-162,169-171 

Indonesia 24,44,54,58, 
79-81 

Indus Delta 60,63,64, 
74 

International 

Geosphere-Biosphere 
Programme (IGBP) 
12 

International Society for 
Mangrove 
Ecosystems (ISME) 
12 

International Tropical 

Timber 
Orgamzation 
(ITTO) 9,11 

Iran 158,159,169 

Iraq 169 

Irian Jaya 54,81 

Iriomote Island 58, 77 

Irrawaddy Delta 60, 75 

Ishigaki Island 58, 77 

Isla de Pinos 124 

Isla Puna 127 

lUCN 5CC World 

Conservation Union 



Jaffna Peninsula 62, 74 
Jakarta 79 
Jamaica 95, 108, 124 
Jamuna 74 



Japan 44,58,77 

Java 54,79,80 

Java Sea 80 

Jeddah 169 

JobosBay 115 

Jordan 169 

Joseph Bonaparte Gulf 
90 

K 

Kahmantan 54, 80 

Kahnot Hor 63 

Kanddia candel 37, 44, 58 

Karachi 60,74 

Kenya 158,165,170 

Kep River 46 

KepulauanAru 81 

Kepulauan Barat Daya 81 

Kepulauan Kai 81 

Kepulauan Mentawai 79 

Kepulauan Obi 81 

Kepulauan Sula 81 

Kepulauan Tanimbar 81 

Khartoum 169 

Khmer Rouge 46 

Kiire 58 

Kikaiga 77 

Kilwa 167,170 

Kimberley, Coast of 90 

King Edward River 90 

King Sound 90 

Kingston (Jamaica) 124 

Kingstown (St Vincent) 
125 

Kinshasa 156 

Klong Ngao River 67 

Koh Kong Bay 46, 75 

Koh Pao River 46 

Kolumadulu AtoU 170 

Koncoure River 154 

KosiBay 167,171 

Kourou 103 

Kra Buri River 67 

Krishna Delta 53,74 

Kuala Lumpur 79 

Kume 77 

Kuran Strait 159,169 

Kutch,Gulfof 53,74 

Kuwait 169 

Kyushu 58,77 



176 



World Mangrove Atlas 



La Digue 160 

Lagos 145,155 

Lagos Lagoon 145,155 

Laguncularia racemosa 38, 
95,130 

Lakshadweep Islands 74 

Lamu 165,170 

Landsat 18 

MSS 18,148,149 

TM 18,67 

Laos 75, 76 

latitudinal hniits 29 

Leeward Islands 125 

Lekki 145,155 

Lempa.Rio 102,123 

Lesotho 171 

Lesser Antilles 95, 
109-112,125 

Lesser Sunda Islands 54, 
80,81 

Leyte 78 

Liberia 130,144,155 

Libreville 134,156 

Litde Cayman 98 

Lombok 80 

Lome 155 

Long Island 124 

Longa, Rio 129, 156 

Los Mochis 122 

Louisiade Archipelago 93 

Louisiana 117 

Loyalty Islands 92 

Luanda 156 

Lubinda River 130 

Lumnitzera 28 

littorea 44, 83 

racemosa 44, 83, 158 

X rosea 44, 83 
Luzon 78 

M 

Macao 76 

Madagascar 158, 

165-166, 170, 171 

Madras 74 

Maewo 92 

Mafia Island 170 

Magdalena, Rio 127 

Mahajamba Bay 165,171 



Mahajanga 166,171 
Mahanadi Delta 53, 74 
Mahe 160 
Mai Po Marsh 52 
Maintirano 165,171 
Malabo 155,156 
Malaita 93 

Malaysia 44,59,78,79, 
80 

Maldives 74,158,160, 
161,170 

MaleAtoU 170 

Malekula 92 

Mah 155 

Malindi 170 

Malonda Lagoon 132 

Malosmadulu Atoll 170 

Maluku 81 

Mamberamo 81 

Managua 123 

Manama 169 

Manambolo 171 

Manchon Lagoons 123 

Mangalore 74 

Mangoky, River 171 

mangrove 
areal estimates 21 , 23 
definition 11, 19 
discontinuities 28 
distribution 23-39 
forestry 11,59,139 
introductions 29, 82, 158 
loss 11,24,29,43,94 
mapping 15-21 
plantations 24, 45, 71 
species 19,25 
uses 11,43,94,129,157 
vicariants 28 

Mania, River 171 

Manila 78 

mapping, history of 14 

Maputo Bay 166, 171 

Maracaibo Strait 118 

Maracaibo, Lago de 118, 
127 

Maranhao 98 

Marie-Galante 125 

Marovoay 171 

Marshall Islands 92 

Martimque 109,111,125 

Mary River 90 



Maseru 171 

Massawa 169 

Mataje Estuary 101,127 

Matang 59,79 

Mathurin Bay 160 

Mauritania 130, 145, 154 

Mauritius 158,160,161, 
171 

Mayotte 160,161,170 

Mayumba 156 

Mazadan 122 

Mbabane 171 

Mbim 133,156 

McArthur River 91 

Meghna River 45 

Mekong Delta 71,75,76 

Melbourne 91 

Melville Island 90 

Mergui Archipelago 75 

Merida 122 

Mexico 95,113,122,123 

Gulf of 122, 124 

Mfolozi River 167,171 

Miami 124 

Middle East 157-171 

Miladummadulu AtoU 
170 

Mindanao 61,78 

Mindoro 78 

Misool 81 

Mississippi 117,122 

Miyako 77 

Mngazana Estuary 167 

Mo(;ambique 166, 171 

Mogadishu 170 

Moheli 160 

Moluccas 81 

Mombasa 165,170 

Mondah Estuary 135 

Mono River 131 

Monrovia 155 

Monte Cristi 100, 124 

Monterrico Lagoons 107 

Montserrat 109,111,125 

Mora oleifera 95 

Morondava 171 

Moroni 170 

MorrocoyBay 118,127 

Mount Cameroon 132, 

156 
Mozambique 158,166, 

171 



Mozambique current 
166 

Mulaku Atoll 170 

Mum 133,156 

Muscat 169 

Myanmar 44, 60, 75 



N 

N'Dougou Bay 136, 138 

Nahoon River 167 

Nariva Swamp 116,126 

Narmada 74 

Nasalis larvatus 54 

Nassau 124 

National Committee on 
Wedands, Mangroves 
and Coral Reefs 
(India) 53 

National Forestry PoUcy 
(Cuba) 100 

National Mangrove 
Committee (India) 
53 

National Mangrove 
Committees 12, 43 

Nearchus and 

Theophrastus 159 

Negombo Lagoon 62, 74 

Negros 61,78 

Netherlands Antilles 
(leeward group) 96, 
127 

Netherlands Antilles 
(windward group) 
109,111 

New Britain 93 

NewCaledoraa 83,85, 
86,92 

New Georgia 93 

New Ireland 93 

New Orieans 122 

New Zealand 83,85,87, 
92 

Nicaragua 95,113-114, 
123 

Nicaragua, Lago de 123 

Nicoya, Golfo de 100, 
123 

Niger Delta 145,155 

Nigeria 24,130, 

145-146, 155, 156 

NilanduAtoU 170 

NOAA-AVHRR 18,48 

North America 94 



Index 



177 



North West Africa 154 
North West Cape 
(Austraha) 90 
Nosy Be 171 
Nouakchott 154 
Noumea 92 
Ntetn 133,156 
Nuku'alofa 92 
Nusa Tenggara 54, 80, 81 
Nypa 28 
Jmticans 21,29,44,83, 
95, 130 

o 

Ococito, Rio 123 

Ogooue 134,156 

Okinawa 77 

Okino-Erabu 77 

Oman, Gulf of 158-160, 
169 

Orinoco River 118,126 

Osbornia octodonta 44, 83 



Pacific Ocean 81,82,92, 
93, 122, 123, 127 

Pakistan 44,60-61,63, 
74 

Palau 83,92 

Palawan 61,78 

Panama 95,114,123,127 

Panay 78 

Pangani River 167,170 

Panuco, Rio 122 

Papua New Guinea 83, 
88-89, 92, 93 

Papua, Gulf of 88,93 

Para 98 

Paramaribo 126 

Paria,Gulfof 118,126 

Parrot Cay 117 

Paz, Rio 107,123 

Pellidem 29 

rhizophorae 28,29,37,95 

Pemba Island 170 

Pemphis acidula 44,83, 
158 

Peninsula (Australia) 90 

Peninsula de Osa 123 

Peninsular Malaysia 59, 
79 



Pentecost 92 

Persian Gulf see Arabian 
Gulf 

Perth 90 

Peru 95,114-115,127 

Philippine Sea 78 

Philippines 44,61,78 

PhnomPenh 75,76 

Phuket 75,79 

Pichavaram 55-57, 74 

Piso, Lake 144,155 

Piura River 114,127 

Plymouth 125 

Pom Lagoon 113 

Pomeroon River 107, 
126 

Port au Prince 124 

PortGentil 156 

Port Harcourt 155 

Port Louis 171 

Port Moresby 88,92,93 

Port of Spain 126 

Port Sudan 169 

Port-Vila 92 

Porto Novo 155 

Porto Novo Marine 
Research Station 
(India) 55 

Praslin 160 
Pretoria 171 
Princess Charlotte Bay 
91 

proboscis monkey 54 

protected areas 24 

Puerto Princesa 78 

Puerto Rico 95,115,125 

Pulau Dolok 81 

Punta San Juan (El 

Salvador) 102,123 

Puttalam Lagoon 62, 74 



Qatar 158,160,169 
Qeshm Island 159,169 
Quito 127 

R 

Rajang River 59, 80 
Ramu River 88,93 
Rangoon 60, 75 



Ranong 21,67-70,75 

Ras al Khafji 158, 169 

Recife 128 

Red Sea 162-164, 169 

reflectance 15 

remote sensing 15 

Rennell 93 

resolution 17 

Reumon 160,171 

ReyRio del 145 

Rhizophora 28 

apiculata 28,33,44,83 

harrisonii 39,95,130 

mangle 28,29,38,82,95, 
130 

mucronata 29,32,44,83, 
158 

racemosa 29,39,95,130, 
158 

samoensis 82, 83 

stylosa 33,44,83 

X lamarckii 44, 83 

X sclala 83 
Rio de Janeiro 98,128 
Robe River 90 
Rodrigues 160,171 
Roper River 91 
Roseau 125 
Rufiji River 167, 170 
Ruvu River 167, 170 
Ruvuma River 167, 170 
Ryukyu Islands 58, 77 



Sabah 59,78,80 
Sabaki River 165 
Sabana, Archipelago de 
124 

Salala 165 

Salomon Islands 170 
Saloum River 146,148, 

154 
Salvador 128 
Samar 61,78 
San Cristobal 93 
San Jose 123 
San Juan (Puerto Rico) 

115,125 

San Juan River 

(Venezuela) 118 

San Miguel, Golfo de 
114,127 



San Salvador 123 

Sana'a 169 

Sanaga River 156 

Santa Catarina 98, 128 

Santa Isabel 93 

Santiago Estuary 101, 
127 

Santo Doiningo 124 

Santuario Nacional los 
Manglares de 
Tumbes 115 

Sao Francisco, Rio 128 

Sao Paulo 128 

Sao Sebastiao, Punta 
166,171 

Sao Tome and Principe 
130,146,155,156 
Sarawak 59,80 
Sarawak River 80 
Sassandra River 155 
sateUite imagery 18 

Saudi Arabia 158,162, 

163,169 
Save River 166, 171 
scale 17 
Scarlet ibis 116 
Scientific Committee on 

Oceanic Research 

(SCOR) 12 

Scyphiphora hydrophyllacea 

44,83 
Senegal 130,146,148, 

154 

Senegal River 145, 154 

Senkaku Islands 77 

Sepik River 88,93 

SeycheUes 158,161,170 

Shark Bay 90 

ShattalArab 158 

Sherbro Island 147, 154 

Side Looking Airborne 
Radar (SLAR) 18 

Sierra Leone 130,147, 
154 

Silhouette 160 

Sinai Peninsula 169 

Sine-Saloum 21, 
148-152,154 

Singapore 44, 62, 79 

Sint Nicolaas 127 

Sittoung 75 

Socotra 162,169 

Solomon Islands 83,85, 
87,92,93 



178 



World Mangrove Atlas 



Solomon Sea 93 

Somalia 15«, 162, 164, 
169, 170 

Soniniani Bay 63, 65, 74 

Sonnemtia 28 

alba 28, 32, 44, 83, 158 

apetala 28,36,44 

caseolaris 33,44,83,158 

Sriffithii 28,36,44 

lanccolata 35,44,83 

ouala 28,35,44,83 

X guln^ai 44, 83 

X urama 44, 83 

South Africa 158,167, 
171 

South America 94-127 

South Asia 43-81 

South China Sea 76, 77, 
78,79 

South Mahavavy 165 

South Pacific 85-88 

South Pacific Islands 92 

Southwest Africa 156 

Southeast Asia 43-81,75 

species hsts, key to 25 

SPOT 18,48,50,63, 
103,105,139-141, 
148,151 

SPOT HRV 18, 148 

Sri Lanka 44, 62, 74 

StBarthelemy 109,111, 
125 

St Croix 125 

St George's 125 

St John's 125 

St Kitts and Nevis 109, 
112,125 

St Lucia 109,112,125 

St Lucia Estuary (South 
Africa) 167 

St Lucia, Lake (South 
Africa) 167, 171 

St Martin 109,111,125 

St Vincent 109,112,125 

Straits of Hormuz 158, 
169 

Straits of Malacca 79 

Sudan 158,164,169 

Sulawesi 54,80,81 

Sulu Archipelago 61,78 

Sulu Sea 78 

Sumatra 54, 79 

Sumba 80 



Sumbawa 80 

Sundarbans 45,53,74,75 

Surabaya 80 

Surinam 95,103,116, 
126 

Suva 92 

Suvadiva Atoll 170 

Swaziland 171 

Sydney 91 

Syinphottia ^^hbulifcra 2 1 , 
118 



T'aipei 77 

Tabebuia palustria 95 

Tacarigua Lagoon 118, 
126 

Taiwan 44, 52, 77 

Taiiiil Nadu State 55 

Tampa Bay 117,124 

Tampico 122 

Tana River 165,170 

Tanega 77 

Tanga 167,170 

Tanzama 158, 167,170 

Tasmama 84 

Teacapan, Laguna 113, 
122 

Tegucigalpa 122, 123 
Tenasserim 60, 75 
Tendaba 139 
Terininos, Laguna de 
113,122 

Terraba-Sierpe 100,123 

Tethys Sea 27 

Texas 117 

Thailand 44,66,67,70, 
75,79 

Gulf of 66,70,75 

Mangrove Forest 
Research Centre 67 

Tiladummati Atoll 170 

Timor 81 

Timor Sea 90 

Tobago 126 

Togo 130,131,155 

Tokara Islands 77 

Tokashiki 77 

Tokuno 77 

Tonga 83,85,87,92 

Tongatapu 92 



Tonkin, Gulf of 76 

Torrecilla 125 

Townsville 91 

Trimdad and Tobago 95, 
116,126 

Trusan-Lawas River 59 
Tulear 166,171 
Tumaco 127 
Tumbes, Rio 114,127 
Turks and Caicos Islands 

95,117,124 
Turks Islands 117 
TurneffeAtoU 123 
Turner River 90 
Tutong River 46, 80 
Tuvalu 83,92 



u 

United Arab EiTiirates 

158,160,169 

Umted Nations 
Educational, 
Scientific and 
Cultural 
Organization 
(UNESCO) 12 

United Nations 
Environment 
Programme 
(UNEP) 12 

United States of 
America 95, 
117-118,122 

US Virgin Islands 109, 
112 

Usumacinta, Rio 122 



Vanua Levu 92 

Vanuatu 83,88,92 

Venezuela 95,118,126, 
127 

Golfode 127 

Veracruz 122 

Victoria (Australia) 84 

Victoria (Hong Kong) 
76 

Victoria (Seychelles) 170 
Vietnam 44,71,75,76 
Vietnam war 71 
Virgin Islands 

Briash 125 

US 125 



Visayas 61 
Viti Levu 92 
Volta 143,155 

w 

Waini River 107, 126 

Wami River 167,170 

West Africa 129-156, 
155 

West Bengal State 47 

Western Samoa 83,85, 
88,92 

Wia-wia 116 

Wilson's Promontory 91 

Windward Islands 125 

World Conservation 
Monitoring Centre 
(WCMC) 19 

World Conservation 
Union (lUCN) 12 

Wouri River 156 



XiXi River 77 
Xun Jiang 76 

Xylocarpus 28 
granatum 44, 83, 158 
mekongensis 44, 83 



Yaku 77 

Yangon 75 

Yaounde 156 

Yap 92 

Yawn Bay 147,154 

Yemen 158,162,164, 
169 

Yonaguni 77 

Yucatan Peninsula 113 

Yule River 90 



Zaire 130,147,156 

Zaire Estuary 147, 156 

Zambezi Delta 166, 171 

Zanzibar Island 170 

Zapata peninsula 1 00, 
124 

Ziguinchor 154 









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ISME - International Society for Mangrove Ecosystems 

ISME was founded in 1990 as a Society to promote the 
study and research of mangrove ecosystems. It aims to bring 
together scientists and interested organisations with the 
purpose of promoting the conservation, rational 
management and sustainable utilisation of mangroves. It also 
provides an international databank on mangrove ecosystems. 
ISME is a non-governmental organisation with members 
from sixty-six countries. Its secretariat is located in Okinawa, 
Japan. ISME has produced a Charter for Mangroves and has 
carried out projects in Southeast Asia, Africa and Latin 
America. It is currently promoting a mangrove afforestation 
project in Pakistan and it recently produced educational 
literature on mangroves m Vietnam. ISME seeks above all 
to work with people around the world to enhance the 
appreciation of mangroves. 









' 1 >*^''^j£^ 



ITTO - International Tropical Timber Organization 

ITTO is an intergovernmental organisation established by 
a United Nations Conference with a mandate of ensuring 
the implementation of the provisions of the International 
Tropical Timber Agreement (ITTA) concluded in 
November 1983, but currently being renewed. At the 
present time, the ITTO membership consists of 24 tropical 
timber producing countries covering more than 75% of the 
world's tropical forest resources, and 27 consuming member 
countries, accounting for more than 95% of tropical wood 
imports in the world. ITTO encourages dialogue and action 
to improve forest management and the sustainable use of 
tropical forests. It recognises that tropical forests are vitally 
needed for their wealth of genetic diversity, conservation 
and environmental values, but maintains that sustainable 
tropical forest industries can generate social and economic 
benefits in many developing countries, so ensuring the 
survival of the forests. It is with this background that ITTO 
supports projects on mangroves. 



-Ml 



WCMC - The World Conservation Monitoring Centre 

The World Conservation Monitoring Centre, based in 
Cambridge, UK is a joint-venture between the three 
partners in the World Conservation Strategy and its successor 
Caring for The Earth: lUCN - The World Conservation 
Union, UNEP - United Nations Environment Programme 
and WWF - World Wide Fund for Nature. The Centre 
provides information services on the conservation and 
sustainable use of species and ecosystems and supports others 
in the development of their own information systems. 
WCMC has developed a considerable database of forest and 
other habitat distribution within its Biodiversity Map 
Library. It was responsible for the preparation of the 
three-volume Conservation Atlas of Tropical Forests and has a 
number of continuing projects relating to tropical forests 
and coastal habitats and species. 



. 'T- 



The International Society for Mangrove Ecosystems 

The World Conservation Monitoring Centre 

The International Tropical Timber Organization