Oceanus Volume 30 Number 4 Winter 1987/88 - J 3 -* • • .4* .. Caribbean Marine Science ISSN 0029-8182 Oceanus The International Magazine of Marine Science and Policy Volume 30, Number 4, Winter 1987/88 Paul R. Ryan, Ed/tor James H. W. Main, Assistant Editor T. M. Hawley, Editorial Assistant Peter J. Buehler, Fall Intern Editorial Advisory Board 1930 Henry Charnock, Professor of Physical Oceanography, University of Southampton, England Edward D. Goldberg, Professor of Chemistry, Scripps Institution of Oceanography Gotthilf Hempel, Director of the Alfred Wegener Institute for Polar Research, West Germany Charles D. Hollister, Dean of Graduate Studies, Woods Hole Oceanographic Institution John Imbrie, Henry L. Doherty Professor of Oceanography, Brown University John A. Knauss, Professor Emeritus, University of Rhode Island Arthur E. Maxwell, Director of the Institute for Geophysics, University of Texas Timothy R. Parsons, Professor, Institute of Oceanography, University of British Columbia, Canada Allan R. Robinson, Gordon McKay Professor of Geophysical Fluid Dynamics, Harvard University David A. Ross, Chairman, Department of Geology and Geophysics, and Sea Grant Coordinator, Woods Hole Oceanographic Institution Published by Woods Hole Oceanographic Institution Guy W. Nichols, Chairman, Board of Trustees lames S. Coles, President of the Associates John H. Steele, President of the Corporation and Director of the Institution The views expressed in Oceanus are those of the authors and do not necessarily reflect those of the Woods Hole Oceanographic Institution. 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Published by Woods Hole Oceanographic Institution The International Magazine of Marine Science and Policy Please enter my subscription to OCEANUS for Individual: D one year at $22.00 D two years at $39.00 D three years at $56.00 Library or Institution: D one year at $50.00 Please send MY Subscription to: D payment enclosed. (we request prepayment) D bill me Please send a GIFT Subscription to: Name (please print) Street address City State Zip 'Subscribers other than U.S. & Canada please use form inserted at last page. Canadian subscribers add $3.00 per year for postage. by Paul R. Ryan Name (please print) Street address City Donor's Name Address_ State Zip /Books Received COVER: Underwater view of red mangrove. The red sponge growing on the arching prop roots is the Caribbean fire sponge, Tec/an/a ignis. (Photo by Chip Clark) Copyright© 1987 by the Woods Hole Oceanographic Institution. Oceanus (ISSN 0029-8182) is published in March, June, September, and December by the Woods Hole Oceanographic Institution, 93 Water Street, Woods Hole, Massachusetts 02543. Second-class postage paid at Falmouth, Massachusetts; Windsor, Ontario; and additional mailing points. POSTMASTER: Send address changes to Oceanus Subscriber Service Center, P.O. Box 6419, Syracuse, N.Y. 13217. I HAS THE SUBSCRIPTION COUPON BEEN DETACHED? If someone else has made use of the coupon attached to this card, you can still subscribe. Just send a check--$22 for one year (four issues), $39 for two, $56 for three--to this address: Woods Hole Oceanographic Institution Woods Hole, Mass. 02543 Please make checks payable to Woods Hole Oceanographic Institution 19 3O Oceanus Woods Hole Oceanographic Institution Woods Hole, Mass. 02543 Subscription correspondence, U.S. and Canada: All orders should be addressed to Oceanus Subscriber Service Center, P.O. Box 6419, Syracuse, N.Y. 13217. Individual subscription rate: $22 a year; Libraries and institutions, $50. Current copy price, $5.50 — 25% discount on current copy orders for 5 or more; 40% discount to bookstores and newsstands. Please make checks payable to Woods Hole Oceanographic Institution. Subscribers outside the U.S. and Canada, please write: Oceanus, Cambridge University Press, the Edinburgh Building, Shaftesbury Rd., Cambridge CB2 2RU, England. Individual subscription rate £20 a year; Students, £17; Libraries and Institutions, £37. Single copy price, £9. Make checks payable to Cambridge University Press. When sending change of address, please include mailing label. Claims for missing numbers from the U.S. and Canada will be honored within 3 months of publication; overseas, 5 months. SEA FLOOR 2 Introduction: Caribbean Marine Science by John D. Negroponte 9 Cooperative Coastal Ecology at Caribbean Marine Laboratories by lohn C. Ogden 16 Mangrove Swamp Communities by Klaus Rutzler, and Candy Feller 25 Petroleum Pollution in the Caribbean by Donald K. Atwood, Fred /. Burton, lorge E. Corredor, George R. Harvey, Alfonso /. Mata-limenez, Alfonso Vasquez-Botello, and Barry A Wade 33 Caribbean Marine Resources: A Report on Economic Opportunities by A. Meriwether Wilson 42 Geology of the Caribbean by William P. Dillon, N. Terence Edgar, Kathryn M. Scan/on, and Kim D. Klitgord 53 Changing Climate and Caribbean Coastlines by Frank Gable 57 Changing Times for Caribbean Fisheries by Mel Goodwin 65 Intermediate Technologies for Small-Scale Fishermen in the Caribbean by Daniel O. Suman 69 Caribbean Mass Mortalities: A Problem With A Solution by Ernest H. Williams, }r., and Lucy Bunkley Williams 76 Belize by lames H. W. Hain 85 — Jamaica: Managing Marine Resources by Jeremy D. Woodley 87 —Panama: Protection of the Tropics by Jeremy B. C. Jackson 89 The Whalers of Bequia by Nathalie F. R. Ward 94 The Future of the Panama Canal by Ambler H. Moss, }r. [ptroffoQ® 99 Athelstan Spilhaus Renaissance Man by Paul R. Ryan 105 108 [§)©(§ 112 Index /Books Received COVER: Underwater view of red mangrove. The red sponge growing on the arching prop roots is the Caribbean fire sponge, Jedania ignis. (Photo by Chip Clark) Copyright© 1987 by the Woods Hole Oceanographic Institution. Oceanus (ISSN 0029-8182) is published in March, )une, September, and December by the Woods Hole Oceanographic Institution, 93 Water Street, Woods Hole, Massachusetts 02543. Second-class postage paid at Falmouth, Massachusetts; Windsor, Ontario; and additional mailing points. POSTMASTER: Send address changes to Oceanus Subscriber Service Center, P.O. Box 6419, Syracuse, N.Y. 13217. 1 Gulf of Mexico Bahamas Tropic of ^Cayman Islands Caribbean Sea Costa Rica Introduction Caribbean Marine Science by John D. Negroponte Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs /\s you review the impressive body of marine scientific work described in this special issue of Oceanus, keep in mind that the United States is very much a member of the greater Caribbean* family of nations. We are linked by maritime boundaries with seven Turks & Caicos Islands U.S. Virgin Islands British Virgin Islands Anguilla St. Maarten Barbuda Antigua Montserrat Guadeloupe Dominica Martinique St. Lucia Barbados St. Vincent Grenada 21- 18- 15- Puerto Rico St. Croix St. Christopher Nevis Tobago Trinidad Venezuela * For the purposes of this discussion, the greater Caribbean includes the island nations of the Greater and Lesser Antilles, the Bahamas, and countries bordering the Caribbean Sea and Gulf of Mexico, with adjacent waters under their jurisdiction out to 200 nautical miles. 12- 9- Caribbean nations in addition to Mexico. Puerto Rico and the U.S. Virgin Islands play a large role in everyday regional affairs. Our Gulf states, and Florida in particular, figure prominently in Caribbean banking and commerce. Much of our oil passes through the region on its way to refineries around the Gulf of Mexico, or bound for our West Coast via the Panama Canal. By and large, our Caribbean neighbors share our democratic traditions of political and intellectual freedom. We share historical affinities and backgrounds, and in some cases, common colonial origins and language. Millions of Americans visit or live in the region. Many of us are of Caribbean origin, beginning with Alexander Hamilton and continuing to the present. Scientific interactions can do much to build the regional ties and collegia! spirit important to our mutual economic well-being and security. Even during the most strained periods of our relations with some of our Caribbean neighbors, the exchange of information on meteorological conditions, hurricane predictions, and air traffic control was never interrupted. Aside from being a very agreeable place to live or visit or work, the region is of substantial and growing scientific interest to Marine scientific research and Law of the Sea in the Caribbean. Law of the Sea Treaty Max. Maritime Claim (nm = nautical miles) Research Restrictions (see Note1) Signed Ratified •Anguilla(UK) — — 200 nm Fisheries Zone (UK) X Antigua & Barbuda 02/07/83 — 200 nm EEZ X *Aruba(Neth.) 12/10/82 — 200 nm Fisheries Zone (Neth.) X Bahamas 12/10/82 07/29/83 200 nm Fisheries Zone Barbados 12/10/82 — 200 nm EEZ X Belize 12/10/82 08/13/83 3 nm Territorial Sea Brazil 12/10/82 — 200 nm Fisheries Zone X •Brit. Virgin Islands (UK) — — 200 nm Fisheries Zone (UK) X •Cayman Island (UK) — — 200 nm Fisheries Zone (UK) X Colombia 12/10/82 — 200 nm EEZ X Costa Rica 12/10/82 — 200 nm EEZ Cuba 12/10/82 08/15/84 200 nm EEZ X Dominica 03/28/83 — 200 nm EEZ X Dominican Republic 12/10/82 — 200 nm EEZ X El Savador 12/05/84 — 200 nm Territorial Sea *Fr. Guiana (Fr.) 12/10/82 — 200 nm EEZ (Fr.) X Grenada 12/10/82 — 200 nm EEZ X 'Guadeloupe (Fr.) 12/10/82 — 200 nm EEZ (Fr.) X Guatemala 07/08/83 — 200 nm EEZ X Guyana 12/10/82 — 200 nm EEZ2 X Haiti 12/10/82 — 200 nm EEZ Honduras 12/10/82 — 200 nm EEZ X Jamaica 12/10/82 03/21/83 12 nm Territorial Sea 'Martinique (Fr.) 12/10/82 — 200 nm EEZ (Fr.) X Mexico 12/10/82 03/18/83 200 nm EEZ X •Montserrat(UK) — — 200 nm Fisheries Zone (UK) X • Netherlands Antilles (Neth.) 12/10/82 — 200 nm Fisheries Zone (Neth.) X Nicaragua 12/09/84 — 200 nm Territorial Sea X Panama 12/10/82 — 200 nm Territorial Sea •Puerto Rico (U.S.) — — 200 nm EEZ •St. Barthelemy (Fr.) 12/10/82 — 200 nm EEZ (Fr.) X St. Christopher & Nevis 12/07/84 — 200 nm EEZ •St. Croix(U.S.) — — 200 nm EEZ St. Lucia 12/10/82 03/27/85 200 nm EEZ •St. Martin (Fr. & Neth.) 12/10/82 — 200 nm EEZ (Fr.) 12/10/82 — 200 nm Fisheries Zone (Neth.) X St. Vincent & Grenadines 12/10/82 — 200 nm EEZ Suriname 12/10/82 — 200 nm EEZ X Trinidad & Tobago 12/10/82 04/25/86 200 nm EEZ2 X •Turks/Caicos Islands (UK) — — 200 nm Fisheries Zone (UK) X United States — — 200 nm EEZ •U.S. Virgin Islands (U.S.) — — 200 nm EEZ Venezuela — — 200 nm EEZ X * Indicates territory or dependent of country shown in parentheses. 1 Legislation or decree stipulating scientific research jurisdiction. 2 Enabling legislation only. Reference: Ross, David A. and Therese A. Landry, Marine Science Research Boundaries and the Law of the Sea. Woods Hole, MA: Woods Hole Oceanographic Institution, International Marine Science Cooperation Program, 1987. Table prepared by Judith Fenwick. U.S. marine researchers. To put that into perspective, one fifth of all U.S. marine scientific projects requiring research vessel clearance from foreign governments are conducted in the waters of the greater Caribbean. The actual number of projects has doubled in the last five years. Because no part of the Caribbean Sea is beyond 200 nautical miles of land, all of it falls within some coastal nation's potential jurisdiction over marine scientific research. Although the United States does not choose to exercise this right, most other Caribbean countries do. Thus, any single research cruise will likely involve multiple clearances — requiring interaction with government officials and participation of scientists in as many as a dozen countries. Although this bureaucratic maze can be difficult to negotiate, it also provides opportunities for establishing institutional and individual working relationships. These are essential to developing an indigenous marine science infrastructure adequate to address the region's needs in marine research and environmental resource management. There are about 60 ongoing internationally sponsored cooperative projects or programs dealing primarily with marine resources, pollution assessment, and environmental management in the Caribbean. A number of them are described in this issue. Some are small-scale bilateral arrangements, while others are long term and multilateral or regional. Despite this large number of programs, a 1983 survey by the United Nations Education, Scientific, and Cultural Organization (UNESCO) counted only 1 1 7 marine scientists in the island nations of the Caribbean, of whom fewer than half are in the small island countries. In Latin American countries bordering the region, UNESCO lists 583 marine scientists, but only 63 of them are in the small Central American countries. It is difficult for these individuals, who usually have full-time responsibilities in their own institutions, to find the time or energy to participate fully in cooperative programs. Clearly, in the smaller countries, the resources of the Caribbean scientific community are being spread very thin. It we really want to do cooperative research, it would seem prudent to place a very high priority on building education and training opportunities into ongoing programs to develop new scientific talent in the region. I would argue that these opportunities should be made available by strengthening institutions within the region as much as possible. The classic "brain drain" scenario is all too real in the smaller countries of the Caribbean — enthusiastic young marine scientists studying abroad, but never going back because there is no science infrastructure to support work in their field, although their skills are sorely needed. I commend the academic institutions that are engaged in cooperative programs at the institutional level, however modest. They are wisely investing in the long-term future of regional marine science collaboration by strengthening the research capabilities of their institutional counterparts. Institution building is a slow process, but there is much that governments can do in the near term. While the State Department's primary role in international scientific affairs is policy guidance and coordination, we advocate, when possible, research with practical applications. In the Caribbean region, marine science bears importantly on both income generation and environmental protection. We encourage all nations to treat these two objectives together, and the Caribbean countries recognize that tourism, fisheries, and mariculture depend on a clean and healthy marine environment. In this connection, the United States encouraged the recent establishment in Kingston, Jamaica, of the Regional Coordinating Unit (RCU) of the United Nations Environmental Programme's (UNEP's) Caribbean Environment Program. The National Oceanic and Atmospheric Administration (NOAA) has offered to make available a full- time scientific advisor to the RCU. We also supported the Intergovernmental Oceanographic Commission's IOCARIBE Secretariat in its first seven years, and are pleased that it now has a permanent office in Cartagena, Colombia. Both the IOCARIBE office and the RCU can play useful roles in coordinating regional marine research and its application to environmental management problems. The United States also participated in the UNEP-sponsored negotiation of the 1983 Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region (Cartagena Convention — see page 6) and the related Oil Spill Protocol. We were an original signatory and one of the first to ratify these instruments, which entered into force earlier this year. Additional protocols are envisioned to give substance to the Cartagena Convention's broad aim of marine environmental protection. The First Meeting of Parties, held in October 1987, decided to call a meeting of experts to draft a Protocol on Specially Protected Areas and Wildlife, and also agreed to actively pursue the development of a Protocol on Marine Pollution The Cartagena Convention On March 24, 1983, the United States, 76 other nations, and two economic organizations meeting at Cartagena de Indias, Colombia, adopted an international agreement pledging cooperation among Caribbean nations to control pollution and guide the development of the region's marine resources in a manner that protects the quality of the environment (see Oceanus, Vol. 27, No. 3, page 85). The Convention for the Protection and Development of the Marine Environment of the Wider Caribbean Region (the Cartagena Convention), calls upon nations in the region to assume the responsibilities to control marine pollution from land-based sources, atmospheric sources, dumping, seabed activities, and vessels. It announces a common commitment to principles of sustainable development and environmental stewardship to guide exploitation and protection of the region's marine resources. The Cartagena Convention entered into force in October 1 986, after winning formal approval by nine nations in the region. The United States played a leading role during the negotiations and was one of the first nations to ratify the treaty. In transmitting the treaty to the Senate for its advice and consent, President Reagan called it "an important step in creating, in the region, marine pollution standards which are generally higher [than current standards]." To date, the following countries have ratified the Convention and its associated protocol on cooperation in combating oil spills: France, the United States, Britain, Antigua and Barbuda, Barbados, the Netherlands, Trinidad and Tobago, Jamaica, Mexico, and Venezuela. Grenada and Saint Lucia have ratified the Convention (document containing the broad principles) but have not ratified the protocol (addendum agreement setting forth more specific obligations). The Cartagena Convention, like others developed under the Regional Seas Program of the United Nations Environment Programme (UNEP), was designed to be an "umbrella" agreement articulating general principles. During the years ahead, additional protocols will be developed under the "Cartagena umbrella" to spell out in more detail legal duties to be undertaken in connection with the treaty's announced principles. By negotiating broad principles first, differing interests and perspectives were accommodated. It is hoped that over time, governments will be able to accept increasingly specific obligations as set forth in additional protocols. The first meeting of nations that have deposited instruments of ratification to the Cartagena Convention was held October 26 to 28, 1987, on the French island of Guadeloupe. At the first meeting, parties to the treaty agreed to defer the adoption of rules of procedure until the next meeting, in 1 989. Parties a/so agreed to further pursue additional protocols to be developed under the Convention, including one on specially-protected areas and wildlife, and one on land-based source pollution. The Wider Caribbean region defined in the Cartagena Convention encompasses the marine environment of the Caribbean Sea and the Gulf of Mexico, including the waters of the United States Exclusive Economic Zone (within 200 miles of U.S. shores) south of 30 degrees North latitude (approximately 50 miles south of the Florida- Georgia border). The 27 countries located in the Wider Caribbean region are linked by certain shared living resources, and similar coastal development and resource management dilemmas. Vast differences in wealth among nations in the region have led to unequal abilities to actively participate in solving regional problems. Given the economic difficulties facing many nations in the Caribbean, it is vital that the United States follows through on President Reagan's recommendation in 1983 that the United States play a "leading role in the effective implementation of the Convention." — Miranda Wecker, Council on Ocean Law, Washington, D.C. Acknowledgment Support for a joint project by the Council on Ocean Law and the Coastal States Organization has been provided by The William H. Donner Foundation. The goal of the project is to bring this regional treaty process to the attention of the U.S. states and affiliated islands in affected areas, and identify priorities to be addressed at meetings of the Cartagena Convention. from Land-based Sources. Both are potentially valuable, and we expect that scientists familiar with these problems will be willing to contribute to their framing and implementation. While we look forward to working with other signatories within the provisions of the Convention, we also have initiated a number of region-wide activities on our own. The President's Caribbean Basin Initiative, enacted by Congress in 1983, is intended to provide special incentives for U.S. -Caribbean trade, balance of payments support, and development assistance, thereby promoting the The Caribbean Basin Initiative I he Caribbean Basin Initiative (CBI) is a program to promote economic development and political stability in Central America and the Caribbean Islands through private sector initiative. The goal is to attract foreign and domestic investment to these countries in new industries, diversifying the economies, and expanding exports. The major elements of the program are: • Duty-free entry to the United States for a wide range of products manufactured in CBI countries, as an incentive for investment and expanded export production. • Increased U.S. economic aid to the region to promote trade, investment, and private sector growth. Aid has more than tripled during 1981 -1986 and is being used to finance critical imports from the United States, establish development banks, provide project financing, fund market research and other technical assistance for exporters, to train management and labor, and build free trade zones. • Caribbean Basin country self-help efforts to improve the local business environment and eliminate excessive bureaucratic red- tape for investors and traders. • A deduction on U.S. taxes for conventions and business meetings held in qualifying CBI countries, to stimulate tourism. • A wide range of U.S. Government, state government, and private sector business- support programs, including trade and investment financing, technical assistance, and business development missions. • Multilateral support from other trading partners, and from such development institutions as the Inter-American Development Bank and World Bank. For example, Canada is implementing Caribcan, providing duty-free entry to Canada for products from the Commonwealth Caribbean. The 22 participating Caribbean Basin countries are: Antigua and Barbuda, Aruba, Bahamas, Barbados, Belize, British Virgin Islands, Costa Rica, Dominica, Dominican Republic, El Salvador, Grenada, Trinidad and Tobago, Guatemala, Haiti, Honduras, /ama/ca, Montserrat, Netherlands Antilles, Panama, St. Christopher- Nevis, St. Lucia, and St. Vincent and the Grenadines. Countries eligible, but not participating in the CBI, are Anguilla, Cayman Islands, Guyana, Nicaragua, Suriname, and Turks and Caicos Islands. CBI Progress Although U.S. imports from CBI countries decreased 22 percent during the first two years of the CBI program, this decline can be accounted for entirely by the substantial drop in the value of petroleum imports from the region. The good news is U.S. imports of nonpetroleum products from the region grew more than 12 percent in 1984-85. High growth rates were registered for a variety of nontraditional products, such as apparel, fruits, and vegetables. The seafood sector performed even better. There is strong interest among U.S. investors. Between September 1 983 and November 1 986, the Overseas Private Investment Corporation provided $168 million in financial support for 59 projects in the CBI region, and insured 129 investments totaling $793 million. The CBI is having an impact, but there is no dramatic difference yet in living standards in the Caribbean Basin. Real Gross Domestic Product (GDP) growth in the CBI region was around 2 percent in 1986. This is encouraging when compared to the declines in GDP experienced by many of these countries in the recent past, but is still below population growth. For further information, contact the CBI Center at (202) 377-0703. The Center is located in Room H-3020, U.S. Department of Commerce, 14th Street and Constitution Avenue, N.W., Washington, D.C. 20230. economic development and political stability of Basin nations through private sector initiatives. The United States Agency for International Development (USAID) is supporting the development of promising agriculture and mariculture activities in the Caribbean. Two new multipurpose marine parks are being created with USAID funding in Belize and Haiti to promote sustainable use of marine resources. The Ocean Studies Board of the National Academy of Sciences, at my request, developed a scientific plan for a resource-oriented marine science initiative in the region. This plan has already served as a catalyst for scientific activities in the region, such as the proposal prepared by the Association of Island Marine Laboratories of the Caribbean (see page 13). Elsewhere in this issue (page 33) is a summary of an Inventory of Caribbean Marine Resources produced by the National Oceanic and Atmospheric Administration in collaboration with USAID and the Intergovernmental Oceanographic Commission. The list could go on, but I think I have made my point. The Caribbean is important to us, and cooperative marine science activities serve vital U.S. interests in the region in improving international relations, in enhancing environmental quality, and in promoting mutual economic interests. I am pleased to have the opportunity to introduce this special issue of Oceanus, and I commend the scientific community for its contributions to the region, as reflected in the articles that follow. Keep up the good work! John D. Negroponte was confirmed as the Assistant Secretary of State for Oceans and International Environmental and Scientific Affairs in July 1985. From November 1981 to June 1 985 he was U.S. Ambassador to Honduras. Since this article was prepared, the author has been appointed Deputy Assistant to the President for National Security Affairs. Acknowledgment Oceanus magazine would like to thank the Woods Hole Oceanographic Institution's Sea Grant Program for its support of this issue. Special Student Rate! We remind you that students at all levels can enter or renew subscriptions at the rate of $17 for one year, a saving of $5. This special rate is available through application to: Oceanus, Woods Hole Oceanographic Institution, Woods Hole, Mass, 02543. AIMLC Meeting The 2 1 st Annual Meeting of the Association of Island Marine Laboratories of the Caribbean will be held May 24-27, 1988 at Mote Marine Laboratory in Sarasota, Florida. Sessions on marine biology, chemistry and toxicology, geology, fisheries, underwater park management, seagrasses, mangroves, and coral reefs will be highlighted as special areas of study. For more information, contact Linda Franklin at Mote Marine Laboratory 1600 City Island Park, Sarasota, Florida 34236. Phone (813)388-4441. 8 Cooperative Coastal Ecology at Caribbean Marine Laboratories by John C. Ogden I he Caribbean is a microcosm of tropical coastal seas throughout the world, containing political, economic, and environmental problems common to similar areas in the Pacific and Indian oceans. Its waters, from Central America north to the Bahamas and east to the Lesser Antilles, are shared by many nations of various sizes. So the Caribbean, more than any other sea except perhaps the Mediterranean, offers ecologists a challenge, an opportunity, and even an obligation for cooperative international marine research and resource management. During the next decade, the region will undergo significant changes. Population is exploding, and lands are being developed at an ever- increasing rate. We are expecting to see more cases of over-exploited fisheries; on Jamaica's north coast this situation has already virtually emptied the reefs of many species of demersal, or bottom-feeding, fish. Agriculture, industry, and tourism are responsible for poor land-use practices near large and small rivers on practically every coast in the Caribbean. The increasing population, and hillsides stripped of vegetation, send large volumes of sediment into the coastal zone, destroying mangrove forests, and smothering seagrass beds and coral reefs under a load of silt and sewage — reminding one of the similar ecological disaster at Kaneohe Bay on the Hawaiian island of Oahu. Governments are aware of the need for information on their own marine environments, but until now have been reluctant to pool their respective resources and address the problems on a regional basis. However, through the efforts of the United Nations Educational, Scientific, and Cultural Organization (UNESCO) Coastal Marine Program (COMAR), and the Intergovernmental Oceanographic Commission (IOC), the political groundwork has been laid for international cooperation in marine science and resource management. Marine scientists in the Caribbean, for their part, have begun networking among themselves to establish procedures that will build a regional body of knowledge. One example of such cooperation is the Caribbean Pollution Research and Monitoring group, CARIPOL (see article, page 25), formed as a specialized venture of the IOC. A Unified System The Caribbean measures approximately 500 miles by 1,200 miles — a relatively small area, oceano- graphically speaking — and is swept from east to west by the Caribbean current, with coastal counter- currents and several large gyres. Because most of the marine plants and animals in the Caribbean have a planktonic larval phase that lasts from several weeks to more than a year, and the propagules are carried long distances by the east-west current, the homogeneity of species associations in these waters is striking. The homogeneity of the Caribbean was dramatized in 1983-84 by a mass mortality, killing 95 to 99 percent of the long-spined black sea urchin, Diadema antillarum (see article, page 69). Haris A. Lessios, a biologist at the Smithsonian Tropical Research Institute in Panama, believes the mass The surface currents of the Caribbean Sea. Land Mangrove , Stand Terrestrial Influence The Caribbean coastal seascape, showing the relationships of coral reefs, seagrasses, and mangroves. The arrows show generalized gradients of terrestrial and oceanic factors that influence the distribution, structure, and productivity of these coastal ecosystems. mortality was caused by a pathogen such as a virus, protozoan, or fungus. The mortality was remarkably species-specific, and spread without loss of severity along surface current patterns. The disappearance of the heretofore abundant plant-eating urchin in turn caused an eruption of algal growth, destroying corals and other reef-dwelling organisms. Most island and mainland coastlines drop precipitously to depths of more than 2,000 meters within a few kilometers of shore, so the total area of the coastal zone — the shallow water (less than 200 meters deep) that man is most dependent on for food, and the zone most susceptible to the influence of man — is small. Typical of tropical seas, however, is the fact that the warm surface waters of the Caribbean rarely mix with the nutrient-rich, cold waters below. Nutrients, particularly inorganic nitrogen and phosphorus, are regenerated from decaying plant and animal material by bacteria, and are the fertilizers of the plant growth that supports all other forms of life. Because these nutrients remain locked away in the deep, cold waters offshore, the primary productivity, or the rate at which plant material is produced in photosynthesis, of the open sea is low. Most fisheries and renewable marine resources are located in the coastal zone where nutrients are concentrated from other, land-based, sources and primary productivity is high. Given its range of island sizes, the size of their coastal zones, and the uniformity in distribution of many of its plants and animals, the Caribbean presents marine biologists with a unique opportunity to discover the factors that control the distribution and abundance of organisms, and those that control the productivity of coastal ecosystems. As the foundation of this basic regional information becomes more firmly established, critical resource management problems can be addressed more effectively. The Caribbean Coastal Seascape The coastal seascape of the Caribbean supports a complex interaction of three distinct ecosystems: mangrove stands, seagrass beds, and coral reefs. Distinct in their solutions to the ecological "problem" of obtaining the nutrients lacking in warm surface waters, these tropical marine ecosystems are among the most productive in the world. In terms of biomass production per unit time, they exceed even intensively cultivated crops such as sugar cane. Lush mangrove forests, consisting of several species of trees, are found in river basins, coastal floodplains, and estuaries. In these and other protected areas, their root systems collect the abundant nutrients from runoff and river discharge. There appears to be a gradient in the size of mangrove stands in the Caribbean, with the most impressive forests along the coasts of the Greater Antilles with their extensive river systems, and a virtual absence of mangroves on the smaller islands of the eastern Caribbean. Similarly, the most productive seagrass beds, dominated by turtle grass, Thalassia testudinum, occur where their roots take advantage of the nutrient enhancement from river runoff or outwelling from coastal mangrove lagoons. During times of highest tides and during storms, the nutrients collected in these lagoons get flushed out into the open water, fertilizing the rooted plants growing there. In a gradient that mirrors that of mangrove stand sizes, the seagrass beds become increasingly diverse, with turtle grass decreasing in importance in favor of seagrasses with lower nutrient requirements, as one moves from larger to smaller islands. Corals contrast with both seagrass and mangroves by regenerating nutrients internally, rather than collecting them through roots. In their association with unicellular algae called zooxanthellae, corals are able to thrive in the warm and shallow, but nutrient-poor waters at the edge of the coastal shelf. Algal turfs, containing nitrogen- fixing blue-green algae, are responsible for a large component of the high productivity of coral reefs. Interaction of Caribbean Coastal Ecosystems The dynamics of nutrient exchange, and other basic aspects of how mangrove, seagrass, and coral ecosystems interact in the Caribbean are only now beginning to be understood. The Smithsonian Institution's National Museum of Natural History is helping this effort by sponsoring a regional program of research known as Caribbean Coral Reef Ecosystems (CCRE), headquartered in Belize, but with additional research sites planned for elsewhere in the Caribbean (see box, page 1 1 ). Coral reefs buffer the impact of the ocean on 10 Caribbean Coral Reef Ecosystems (CCRE) I he Caribbean Coral Reef Ecosystems (CCRE) program has its roots in a collaborative field research project conceived by six. National Museum of Natural History scientists more than 75 years ago. This initial group of Smithsonian researchers represented several major disciplines that are essential in the study of reef ecology: zoology, botany, carbonate geology, and paleobiology. The immediate aim was the synoptic investigation of Caribbean coral reefs. Since it was expected that comparative studies would eventually be carried into other littoral (shoreline) environments, the original program was named Investigations of Marine Shallow Water Ecosystems (IMSWE). Program logistics and financial constraints made it advisable to establish a field station in one representative location, rather than travel as a group to different places to carry out studies. After a number of dive surveys conducted by us and colleagues from other institutions, we chose the barrier reef of Belize (then British Honduras). This reef complex turned out to be the most diverse in structure, habitat types, and animal and plant species of all locations examined. It could also be considered the most pristine system, with only minimal disturbances from the distant land mass, such as silting and run-off of nutrients and pollutants, and only moderate fishing activities by natives and a few tourists. In February 1972, Carrie Bow Cay, a 0.4 hectare (1 acre) sand island on top of the southern Belize barrier reef was chosen as the site for our field laboratory. During the following decade, some 65 scientists and graduate students worked at the station, and more than WO research papers were published on the fauna, flora, and geology of the Carrie Bow reef tract, culminated by the multidisciplinary volume entitled The Atlantic Barrier Reef Ecosystem at Carrie Bow Cay, Belize, I: Structure and Communities (K. Rutzler and I. G. Macintyre, eds., 7982; Smithsonian Contributions to the Marine Sciences, 12). Grants from the Exxon Corporation's Public Affairs Department (Central and South America) aided the program soon after its inception and, in the early 1980s, stimulated a new focus: ecological study of Caribbean mangrove swamp communities. This new program became known as the Smithsonian Western Atlantic Mangrove Program (SWAMP) and, in addition to the Exxon support, earned a 2-year Smithsonian Scholarly Studies Program award for its 18 staff scientists. Carrie Bow Cay continued to serve as logistical base, with nearby Twin Cays chosen as the model mangrove system. Beginning in Fiscal Year 1985 (October 1984) the National Museum of Natural History, strengthened by the research experience derived from the IMSWE and SWAMP programs, received an increase to its budget base for the study of Caribbean Coral Reef Ecosystems. This "umbrella" program, now known by its acronym CCRE, encompasses reef, mangrove, seagrass meadow, and plankton community studies, and maintains its primary focus on the Carrie Bow Cay, Belize, region. To date, about 50 scientists a year have conducted studies there. In addition, comparative studies in other places in the Caribbean basin have been initiated or are planned. Sites under consideration are: Yucatan (Mexico), Venezuela, St. Vincent, Barbados, Martinique, Guadeloupe, Jamaica, Bermuda, and coastal Florida. The possibility of conducting deep-water studies along the fore-reef slope of the Belize barrier reef is under review. A modest sub-program of fellowship support is augmenting Smithsonian staff research under this program. — Klaus Rutzler, and Marsha Sitnik the coastal zone, creating lagoons and protected waters that favor the growth of seagrasses and mangroves. Mangrove forests and seagrass beds buffer coral reefs from contact with land, and promote reef growth offshore by trapping sediments, removing excessive nutrients, and interrupting freshwater discharge, thus stabilizing the salinity of the coastal zone. Because their environmental requirements are so different, coral reefs and mangroves rarely occur next to each other. It follows then, that some of the most productive coasts are those where broad seagrass meadows are interposed between mangroves and coral reefs. An example of nutrient exchange among these ecosystems is related to the daily or seasonal migration of animals from one ecosystem to another. Judy L. Meyer, an ecologist at the University of Georgia, found that schools of juvenile reef-dwelling grunts, Haemulon spp., act as nutrient transporters; they forage by night among the seagrass beds and defecate by day in the reefs, measurably increasing the nutrient concentrations over coral colonies. Corals with resident grunt schools, carrying these additional nutrients, grew faster than those lacking schools. Seagrass beds and mangroves have been recognized as important nursery areas for many species of reef fishes and invertebrates. Numerous studies at the West Indies Laboratory on St. Croix have shown that the planktonic larvae of the French 11 grunt, Haemulon flavolineatum, preferentially settle in seagrass-covered lagoons where they spend the first few months of their life, moving gradually to coral reefs as small juveniles. As previously mentioned, there seems to be a relationship between the form that mangrove stands and seagrass beds take, and the size of the land mass they are associated with. Research into varying properties of coastal ecosystems in relation to land- mass sizes is an important program, and one that demands international cooperation throughout the Caribbean. By comparing one site to another over a long period of time, the observed differences and similarities may be correlated with particular factors. The insular nature of marine biological research in the Caribbean until now has made comparison between sites difficult because of differing objectives and methods. For this reason, generalizations developed at one site may not apply to other sites. For example, the population density of the common striped parrotfish, Scarus iserti varies directly with the gradient of decreasing land influence from Panama to St. Croix. Its behavior also changes dramatically along the gradient. In Panama, striped parrotfish show an elaborate territorial behavior in addition to group foraging behavior. In St. Croix, territories are not found, and the fish forage over a wide area in small groups. The hypothesis is that territorial behavior in striped parrotfish is possible only where productivity is enhanced and food resources are concentrated. In St. Croix, productivity is depressed and food resources are more widely distributed. The parrotfish adopt a foraging strategy to match their resources. Other relatively simple measures of community structure and function made over long periods of time, along geographical gradients, could resolve important pathways of interaction and tell us a great deal about the factors influencing the structure and productivity of coastal communities. A Cooperative Network There are more than 17 marine laboratories in the Caribbean region, many of which have a long tradition of sharing research results. This is fortunate because many of them — such as the Bellairs Institute of McGill University in Barbados — are just field stations with facilities for about 10 scientists. Individually, their small sizes limit their ability to carry out large research projects independently; but spread out over the Caribbean as they are, together they can take on the sort of regional research necessary for crucial resource management issues. The Association of Island Marine Laboratories of the Caribbean (AIMLC) (page 13), with 24 member laboratories including Florida and Bermuda, was founded in 1 957, and hosts a meeting at a member laboratory nearly every year. At several workshop meetings of Caribbean marine scientists, held at the West Indies Laboratory in St. Croix and the Discovery Bay Marine Laboratory in Jamaica in 1 982 and 1 985, under the sponsorship of the National Science Foundation (NSF) and UNESCO, a program of sustained ecological research, involving a cooperating network of Caribbean marine laboratories was designed. The program, called Caribbean Coastal Marine Productivity (CARICOMP), will establish research sites; map the distribution of coral reefs, seagrasses, and mangroves; and collect monitoring data using standardized methods and techniques. For example, one of the most simple yet useful measures that integrates many aspects of the environment is the growth rate of principal coral, algae, seagrass, and mangrove species. This information, combined with basic physical and chemical data, will be centrally processed and incorporated into regional models of coastal productivity. This developing data base from sites surrounding the Caribbean will suggest further specialized research projects. Research of a regional character, directed at an understanding of the factors controlling coastal ecosystem structure and function, will be the result. The training of Caribbean scientists and technicians in the application of modern techniques in marine science is central to the network. This training should include remote sensing, manned submersibles, remotely operated vehicles (ROVs), and the latest diving technology — exemplified by the National Oceanic and Atmospheric Administration's (NOAA's) new underwater laboratory, Aquarius (see box, page 15). The network will make the best information available for management of marine resources on a regional scale, while stimulating basic research in areas where information is lacking. Research on Various Timescales The network of Caribbean marine laboratories will be able to anticipate and study regional events on short and intermediate timescales, such as hurricanes, larval distribution patterns or mass mortalities, and make real-time maps on a region- wide scale. For example, hurricanes regularly traverse the Caribbean, and may be involved in fish kills caused by phytoplankton blooms stimulated by storm-driven upwelling of nutrients from deep water. Hurricanes destroy the dominant coral species on shallow reefs at intervals, opening space that is re- colonized by a variety of species, and promoting biological diversity. The potential for long-distance distribution of larvae by currents presently makes identification of fisheries stocks difficult, and single- point management of fisheries resources impossible. New techniques involving genetic markers may identify points of origin of larvae and track distribution patterns, providing a rational basis for regional fisheries management. As an example of an event taking place on a longer time scale, "white band disease" of elkhorn coral, Acropora palmata, the principal reef-building coral of the Caribbean, has killed more than 90 percent of this species at Buck Island Reef National Monument in St. Croix, managed by the National Park Service as one of the nation's first underwater parks. The cause of the disease is unknown, but it is found through the islands of the eastern Caribbean and may move to mainland coasts to the south and west. The network could rapidly assemble a picture of such events; relate them to micro- and meso-scale 12 Association of Island Marine Laboratories (AIMLC) ie Association of Island Marine Laboratories of the Caribbean (AIMLC) represents 24 member marine laboratories, primarily in the greater Caribbean basin, and more than 500 individual members with interest in Caribbean marine science. The Association advances Caribbean marine science by arranging meetings; fostering personal and official relations among members; assisting or initiating cooperative research Bellairs Research Institute of McGill University St. lames Barbados Bermuda Biological Station St. George's West Ferry Reach 1-15 Bermuda Bitter End Field Station, Virgin Gorda Fisheries Research Laboratory 6-22406 Southern Illinois University at Carbondale Carbondale, IL 62901 Caraibisch Marien Biologisch Instituut Piscadera Baai P. O. Box 2090 Willemstad, Curacao Netherlands Antilles Caribbean Marine Research Laboratory Lee Stocking Island Bahamas Center for Energy and Environmental Research University of Puerto Rico Mayaguez, PR 00708 Centre de Investigaciones de Biologia Marina Presa de Tavera # 302 Ciudad de los Millones Santo Domingo Republica Dominicana Centro de Investigacion y de Estudios Avanzados del IPN— Unidad Merida Carretera Antigua a Progreso KM 6 Apartado Postal 73 — Cordemex 973 19 Merida, Yucatan Mexico Centre Universitaire Antilles — Guyane B. P. F-97167, Pointe-A-Pitre, Cedex Guadeloupe (F. W. I.) CCFL Bahamian Field Station San Salvador, Bahamas College Center of the Finger Lakes 270 Southwest 34th Street Fort Lauderdale, FL33315 Department of Marine Sciences University of Puerto Rico Mayaguez, PR 00708 programs; and publishing a journal (Proceedings of the Association of Island Marine Laboratories of the Caribbean), a newsletter (Caribbean Marine Sciences), and an address and specialty list of Caribbean scientists. Lucy Bunkley Williams is the editor of the newsletter. Contributions may be submitted to her, or copies obtained from her at: Department of Marine Sciences, University of Puerto Rico, Mayaguez, PR 00708. Below is a list of member laboratories. Discovery Bay Marine Laboratory P. O. Box 35 Discovery Bay Jamaica Estacion de Investigaciones Marinas de Margarita Fundacion La Salle de Ciencias Naturales Apartado 144, Porlamar Nueva Esparta, Venezuela Laboratorio Investigaciones Pesqueras Corporacion para el Desarrollo y Administracion de los Recursos Marines P. O. Box 3665, Maina Station Mayaguez, PR 00708 Fundacion Cientifica Los Roques Apartado 6 1248 Caracas Venezuela Institute of Marine Affairs P.O. Box 3 160 Carenage Post Office Port of Spain Trinidad and Tobago, W. I. Institute de Investigaciones Marinas de Punta de Betin Apartado 1016, Santa Marta Colombia Institute Oceanografico Universidad de Oriente Apartado 94 Cumana Venezuela Marine Science Center College of the Virgin Islands Charlotte Amalie, St. Thomas U.S. Virgin Islands 00802 Mote Marine Laboratory 1600 City Island Park Sarasota, FL 33577 Port Royal Marine Laboratory Department of Zoology University of the West Indies P.O. Box 12 Mona, Kingston 7 lamaica continued page 14 13 continued from page 13 Rosenstiel School of Marine and Atmospheric Sciences University of Miami 4600 Rickenbacker Causeway Miami, FL 331 49 Smithsonian Tropical Research Institute Balboa, Panama APO Miami, FL 34002 West Indies Laboratory Fairleigh Dickinson University league Bay Christiansted, St. Croix U.S. Virgin Islands 00820 The fore reef at Discovery Bay, lamaica, in 1983, three years after Hurricane Allen destroyed most of the shallow water branching corals, Acropora spp., leaving only mounding corals. By periodically destroying the dominant shallow water corals, hurricanes promote biological diversity on coral reefs. The Antillean fish trap is used in the eastern Caribbean subsistence fishery. Traps are commonly set in seagrass beds near coral reefs. circulation patterns; and suggest causes, needed research, and management strategies. On a still longer time scale, sea level is projected to rise rapidly during the next 100 years, potentially interfering with the wave buffering capacity of coral reefs in the coastal zone. A systematic program of coral cores at the network sites will help define the climatic factors and events that have led to the establishment and growth of coral reefs in the Caribbean. Corals, just like trees, have growth rings that are used to infer past conditions (see Oceanus, Vol. 29, No. 2, page 31). Good baseline data will be needed to track sea level, study the growth responses of coral reefs, and anticipate management problems associated with increased wave action in the coastal zone (see article page 53). A coral coring program directed by Peter J. Isdale at the Australian Institute of Marine Science tracked the influence of river flow during the last few hundred years on coral growth. In addition to providing a window on the past, the Caribbean is an ideal intermediate-scale region in which the global system may be modeled. The network of marine laboratories would serve to provide "ground truth" for the new technology being applied to study global change. Data gathered in a coordinated regional program could be used to tune the capabilities and sensitivity of remote sensing technology, and will provide the key to linking the past with the future in our understanding of the tropical coastal zone. lohn C. Ogden is Professor of Biology at Fairleigh Dickinson University, and Director of the University's West Indies Laboratory on St. Croix in the U.S. Virgin Islands. He is also the co-chairman of the Steering Committee of CARICOMP. Acknowledgment The steering committee of CARICOMP, along with a large group of cooperating Caribbean scientists, are responsible for much of the material presented in this article. Selected References Cladfelter, W. B. 1982. White band disease in Acropora palmata: implications for the structure-and growth of shallow reefs. Bulletin of Marine Science 32: 639-643. Lessios, H. A., D. R. Robertson, ). D. Cubit. 1984. Spread of Diadema mass mortality through the Caribbean. Science 226: 335-337. Lewis, J. B. 1977. Processes of organic production on coral reefs. Biological Reviews 52: 305-347. Ogden, ). C., and E. H. Gladfelter (eds.). 1986. Caribbean coastal marine productivity (CARICOMP). Reports in Marine Science No. 41, United Nations Educational, Scientific, and Cultural Organization (UNESCO). Phillips, R. C., and C. P. McRoy, eds. 1980. Handbook of Seagrass Biology. 353 pp. New York: Garland STPM Press. 14 Aquarius: The Dawning of a New Age in Caribbean Marine Science I he National Oceanic and Atmospheric Administration's National Undersea Research Program (NURP) is poised to launch the most advanced undersea laboratory available to the scientific community — a habitat-based, manned saturation* system known as Aquarius. The laboratory/habitat is designed to accommodate up to six scientists at depths reaching 37 meters for as long as a month. Aquarius was recently deployed at Salt River Canyon— less than a kilometer from the mouth of the Salt River, on the north coast of St. Croix — and is currently undergoing final preparation and safety checks for its first science missions, sponsored by NURP at Fairleigh Dickinson University's West Indies Laboratory (NURP-FDU). The value of saturation diving in marine research was proven by Hydrolab, a four-person habitat that was used by NURP-FDU to conduct 85 research projects from 1978 to 1985. Habitats allow scientists to work at depths requiring long decompression times for extended periods. Prolonged stays on the ocean floor permit scientists to establish and monitor in situ experiments using the newest methods, hastening the evolution of undersea science from an observational to an experimental mode. The Aquarius system has four parts: the 81 -ton research habitat; a life-support buoy (LSB); a launch, recovery, and transport vessel; and a 1 18-ton baseplate that holds the habitat on the ocean floor. The LSB is a reinforced 13-meter enclosed boat hull modified for unattended operation. It is connected to the habitat by a 38- meter long, 20-centimeter diameter umbilical that provides the habitat with air, power, water, and communication lines. The larger transport vessel will be able to carry the baseplate and habitat to any number of sites, enabling comparative study of various Caribbean — indeed "Saturation" in the context of diving means that the maximum amount of gases possible are dissolved in a diver's blood at a particular depth. "Decompression" is necessary when a diver's blood contains a greater quantitiy of gases than can normally be eliminated from the blood without the formation of bubbles. Aquarius, NOAA's new underwater research station. global tropical — ecosystems. The surface support personnel of NURP/FDU will provide diver training, operational expertise, and safety standards. Aquarius will expand the productivity of saturation diving for scientific research, for in addition to being a comfortable underwater home, the Aquarius could rightly be called a lab/tat, since it is equipped with modern experimental facilities. The onboard equipment includes video monitoring and recording capability, a computer network, environmental data-logging system, and wet lab. The science missions scheduled for 1 988 will address the general topics of nutrient cycling and recruitment processes in marine organisms. Specifically, the projects will examine: • The effect of water movement on the feeding behavior of corals. • The oxygen dynamics and anaerobic metabolism of reef sediments. • The structural patterns and processes of algal communities along a depth gradient. • The energetics of sediment removal and zooplankton feeding in reef-building corals. • Nutrient fluxes in the benthic microflora of coral reef sediments. • Biological and physical processes affecting larval settlement and early recruitment of marine organisms. Results from this research will help our understanding of relationships between primary productivity, energy and material flow through ecosystems, and the potential availability of this energy and material to higher trophic levels, such as fishes and man. For further information on Aquarius and the NURP-FDU Caribbean Science Program, contact Dr. Robert C. Carpenter, Science Director, West Indies Laboratory, Teague Bay, Christiansted, St. Croix, U.S. Virgin Islands 00820. 15 Mangrove Swamp by Klaus Riitzler, and Candy Feller //-r I he roots gave off clicking sounds, and the odor was disgusting. We felt that we were watching something horrible. No one likes the mangroves." That is how John Steinbeck and Ed Ricketts depicted The bostrychietum community, based on an intertidal association of red algae. Oysters are located at mid-tide and upper-tide levels, while the mangrove tree crab and periwinkle stay above the water line. (Illustration by Candy Feller) 16 Communities the mangroves in 1941 in the Sea of Cortez. Many people agree with them. So why have two dozen scientists from the Smithsonian Institution, primarily from the National Museum of Natural History, and twice as many colleagues from American and European universities and museums devoted a decade of exploration to one square kilometer of "black mud, . . . flies and insects in great numbers . . ., impenetrable . . . mangrove roots . . .," and ". . . stalking, quiet murder"? The study started in the early 1980s, and focuses on an intertidal mangrove island known as Twin Cays, just inside the Tobacco Reef section of the barrier reef of Belize, a tiny Central American nation on the Caribbean coast (see article page 76). The principal purpose of this research is to document the biology, geology, ecological balance, economic importance, and aesthetic value of a prominent coastal ecosystem using the example of a diverse and undisturbed swamp community. Properties of Mangrove Swamps Mangrove swamp communities dominate the world's tropical and subtropical coasts, paralleling the geographical distribution of coral reefs. Mangroves on the Atlantic side of the American coasts occur between Bermuda and almost to the mouth of the Rio de la Plata (Argentina), and throughout the West Indies. Like reefs, mangrove swamps are environments formed by organisms, but unlike most coral communities, they thrive in the intertidal zone and endure a wide range of salinities. "Mangrove" refers to an assemblage of plants from five families with common ecological, morphological, and physiological characteristics that allow them to live in tidal swamps. Worldwide, at least 34 species in nine genera are considered to be true mangroves. P. B. Tomlinson's recent book, Botany of Mangroves, defines this group of plants by five features: 1) they are ecologically restricted to tidal swamps, 2) the major element of the community frequently forms pure stands, 3) the plants are morphologically adapted with aerial roots and viviparity (producing new plants instead of seeds), 4) they are physiologically adapted for salt exclusion or salt excretion, and 5) they are taxonomically isolated from terrestrial relatives, at least at the generic level. "Mangrove swamp" or "mangal" refers to communities characterized by mangrove plants. Mangrove trees are used for water-resistant timber, charcoal, dyes, and medicines. They resist coastal erosion during storms and possibly promote land-building processes by trapping sediment and producing peat. The protective subtidal root system of the red mangrove serves as nursery ground for many commercially valuable species of fishes, shrimps, lobsters, crabs, mussels, and oysters. An assorted fauna of birds, reptiles, and mammals is also at home in the mangrove thickets and tidal channels. Human disturbances have made a heavy impact on many mangroves near populated areas as a result of dredging and filling, overcutting, insect control, and garbage and sewage dumping. The intertidal environment of mangroves is endangered by pollutants in the water, air, and soil. Accidental oil spills appear to be particularly damaging. Oil and tars not only smother algae and invertebrates, but also disrupt the oxygen supply to the root system of the mangrove trees by coating the respiratory pores of the intertidal prop and air roots. A Mangrove Laboratory in Belize Belize (formerly British Honduras), boasts the longest barrier reef of the Northern Hemisphere, extending 220 kilometers from the Mexican border in the north to the Gulf of Honduras in the south. Behind this barrier lies an enormous lagoon system averaging 25 kilometers between the mainland and open ocean. Mangroves border most of the coastline, extend upstream from countless river mouths, and fringe or cover most lagoon cays. One of these is Twin Cays (Figure 1) — an island divided into two by an S-shaped channel. Twin Cays has become our study site and experimental field laboratory. Although we usually spend the nights and conduct laboratory bench work on nearby Carrie Bow Cay — site of the National Museum's coral reef field station for the last 1 5 years — most days and many nights are spent in the mangrove channels, lakes, ponds, mud flats, and even the trees. A self-contained weather station established on one of the mud flats transmits data on wind, sun, rain, temperatures, and tides to a portable computer on Carrie Bow Cay. The bibliographies on mangroves show that during the last 200 years more than 6,000 papers have been published describing biological and geological details from almost as many different swamps over the world. Our ongoing study aims to 17 Sond bores & Patch Reefs Figure 1 . Mangrove ecosystem study area, Twin Cays, Belize. The National Museum of Natural History's coral reef field station is located on Carrie Bow Cay, about 4 kilometers southeast. (From Rutzler and Macintyre, 1982, Smithsonian Contributions to the Marine Sciences 12) analyze as many components as possible of a single mangrove swamp and, ultimately, assemble them to a mosaic reflecting structure as well as function of this unique ecosystem. Geological History of Twin Cays A popular theory holds that mangroves are builders of land because they trap and hold fine sediments. Early on in our study we discovered that this is not necessarily true. We tried to reclaim nearby Curlew Cay, which had been lost to a hurricane (it is now known as Curlew Bank), by planting an assortment of young red mangroves, but were unsuccessful. So the question arose, if islands are not built by mangroves, how do they get started? To learn more about the Holocene (recent time — back to 18,000 years before present) stratigraphy under the present island, Ian G. Macintyre of the Smithsonian Department of Paleobiology, along with Robin G. Lighty and Anne Raymond of Texas A&M University, drove pipes 8 meters into the sediment, down to the Pleistocene level (marks the beginning of the Holocene), and retrieved sediment cores that date back 7,000 years.* They also collected rock cores below this level. What they found below the mangroves was a carbonate substrate consisting of a dense limestone formed mostly by finger corals (Porites) with abundant mollusk fragments, indicating an environment of deposition similar to today's calm- water patch reefs. The sequence of peat, algal- produced sand, and mangrove oysters in the sediment cores indicates that this mangrove was apparently established on a topographic high formed by a fossil patch reef, and kept pace with the rising sea level. However, there is also evidence that the island repeatedly changed its size and shifted position, generally building with lagoon sediments on the windward coasts, while eroding at the leeward edge, which is characterized by shallow- water bottoms formed by stranded peat deposits. The mangrove community itself can be thought of as being composed of three components: the above-water "forest," the intertidal swamp, and * Although the Holocene can date back as much as 18,000 years, there are only 7,000 years of sediment accumulation in this particular area, as sea level did not flood the Belize lagoon until the upper Holocene. 18 Figure 2. Channel fringed by red mangrove. Sponges and other sessile organisms are attached to prop roots and to the underwashed peat bank to the right; turtle grass and algae cover the mud bottom. A black mangrove with short intertidal air roots protruding from the bottom is seen on the left. (After Rutzler, 1969, Proceedings of a Coastal Lagoon Symposium, Mexico City; redrawn by Molly Ryan) the underwater system (Figure 2). In our descriptions, we will start from the bottom and work up. Environments Below the Tides The bottom of the mangrove from the intertidal to 3 meters, the greatest depth of the main channel, is composed of what most people would call muck. To us, it displays many varieties, such as carbonate silt, mud, and sand with varying amounts of mucus, organic detritus (products of plant and animal decay), peat, and silicious skeletons derived from diatom algae and sponges. Many fine-grained limestone sediments are produced by physical and biological erosion on the nearby reef and carried into the mangrove by water currents. Sands, on the other hand, are primarily produced within the community by digestion or decay of calcareous green algae (Halimeda). The most abundant and ecologically important plant on the submerged mangrove bottoms is the turtle grass (Thalassia). It stabilizes the muddy bottom, offers substrate for egg cases and many small sessile organisms, and provides food and shelter to animal groups ranging from microbes to 2-meter manatees. Jorg A. Ott, a seagrass ecologist from the University of Vienna, determined that turtle grass in the Twin Cay mangrove is more dense, and grows 3 times faster than Thalassia in the nearby open lagoon, resulting in an almost 10-fold net leaf production. Red mangrove stilt roots line all channels, creeks, and ponds and, below tide level, support spectacularly colored clusters of algae, sponges, tunicates (sea squirts), anemones, and many associates. They also provide hiding places for many mobile animals, such as crabs, lobsters, sea urchins, and fishes. Algae without the ability to root in mud bottoms abound on the stilt roots. Mark Littler, from the Smithsonian Department of Botany, and co- workers Diane Littler and Philipp Taylor found that, curiously, fleshy algae seem to prefer roots that had penetrated the water surface, but had not yet reached the bottom of the channel or lake. Calcifying algae (such as the sand-producing Halimeda), on the other hand, are common on the submerged parts of anchored roots and along the channel banks. Experiments demonstrated that the hanging roots offer palatable plants protection from benthic (bottom-living) herbivores such as sea urchins and many fishes, whereas Halimeda has its own skeletal protection. Certain algae and many sessile invertebrates on the subtidal mangrove roots are protected from predators by toxic substances stored in their tissues and produced by their own metabolism. Sponges are particularly well-known for their antibiotic and 19 feeding-deterrent properties. The sponges, in turn, are used by many smaller organisms, such as anemones, polychaete worms, shrimps, crabs, amphipod crustaceans, gastropod mollusks, and brittle stars as an effective physical and chemical shelter. Collaborating with our Smithsonian colleagues, Kristian Fauchald, Gordon Hendler (now at the Los Angeles County Museum), and Brian Kensley, we extracted up to 40 species and 400 specimens of endozoans (species living within another) larger than 2.5 millimeters from, as an example, a 1 -liter fire sponge (Tedan/'a), a species that causes burning, itching, and even severe dermatitis in humans. Sponges are among the most common, massive, and colorful invertebrates in the submerged mangrove. To settle and metamorphose, their larvae need solid substrate with low exposure to sedimentation, although we observed grown specimens surviving for months buried in light mud after they had fallen from their place of original attachment. Only two kinds of firm substrate are available to such settlers, red mangrove stilt roots, and vertical or overhanging banks composed of a felt of peat and mangrove rootlets and flushed by tidal currents. In both locations, the competition for space is fierce, not only among sponges, but also between sponges and other sessile organisms, such as algae, hydroids (the polyp-generation of many medusae), corals, anemones, bryozoans (moss animals), and tunicates (sea squirts). With our colleagues Dale Calder, Royal Ontario Museum, Ivan Goodbody, University of the West Indies, and Jan Kohlmeyer, University of North Carolina, we are analyzing the sequence of settlement of species at different seasons, following their growth and methods and hierarchies of competition. We have found that within days new substrates (wood, plastics) are colonized by ubiquitous bacteria, fungi, and lower algae. Next to arrive are coralline algal crusts, sponges, hydroids, scyphozoan polyps (the polyp stage of the upside- down jellyfish Cass/opea), anemones, serpulid and sabellid worms, bryozoans, and ascidians (the latter two are colonial, encrusting organisms). After 3 to 6 months, substrates are fully covered by a spectrum of organisms. This spectrum varies greatly, and depends on the season in which the experiment was started, the habitat position of the substrate, and the environmental endurance of the settlers. Not all subtidal mangrove life is restricted to the bottoms and roots. Fishes of all size and age classes hide or feed in the water column around the red mangrove roots and along the banks. Many of these depend on plankton, such as copepods and other small crustaceans (shrimp-like animals), for food. Members of both groups form characteristic swarms during the day. Smithsonian's Frank Ferrari teamed up with Julie Ambler, Texas A&M University, Ann Bucklin, University of Delaware, and Richard Modlin, University of Alabama, to study the systematics, ecology, and genetics of the swarms and found population densities much greater than expected. They counted more than 2,000 copepods per cubic meter of water in a small bay at night, and estimated 100 million individuals congregated during the day in a band of swarms along a 1,000-meter stretch of channel bank. The Intertidal Mangrove Swamp Although the tidal range in the Caribbean is small, in shallow coastal areas it can strongly influence current flow and distribution of organisms. At Twin Cays, the mean tidal range is only 15 centimeters, yet a combination of astronomical, geomorphologic, and meteorologic factors can cause a range of more than a half meter. Red mangrove (Rhizophora) prop roots, black mangrove (Avicennia) pneumatophores,* peat banks, and mud flats are the typical substrates of the intertidal zone supporting distinctive communities. Barnacles (Chthamalus), wood boring isopods (Limnoria), oysters (Crassosfrea), and "mangrove oysters" (Isognomon, not a true oyster) are the best known indicators of intertidal hard substrates, while fiddler crabs (Uca) are typical for the mud flats. Green algal mats (Caulerpa, Halimeda) are found exposed on peat-mud banks during low tide. The most abundant and characteristic intertidal mangrove community, however, is called the bostrychietum, named after the principal components of an association of red algae (Bostrychia, with Catanella and Ca/og/ossa). The bostrychietum (see page 16) has a remarkable water-holding capacity, which allows the plants and their associated animals to survive extended dry periods. We measured water loss rates in two of the substrate species and found evidence of two different methods of water retention. Bostrychia is a delicate, tufted plant that holds water primarily interstitially (between the branches). Catenella is more fleshy and less elaborately branched, and holds water intracellularly (within the cells), in its tissues. Loren Coen, Dauphin Island Sea Lab, examined the animal associates of the bostrychietum, particularly in respect to grazing. He found that amphipods (Parhyale) become concentrated in the algal mats in high numbers during receding tides, and that their grazing on Bostrychia can match or exceed the algal growth. The mangrove tree crab, Aratus, and other crabs from the low-tide level were also found with large quantities of Bostrychia in their guts. Desiccation and related problems of increased temperature and salinity in organisms subjected to exposure at low tide became particularly apparent during an extreme low tide in June 1983. A 20-centimeter zone below mean low- tide level became exposed during noon hours under a clear sky. Large communities of low intertidal (rarely exposed) and subtidal (never exposed) organisms, * A feature of many mangroves is that some part of the root system is exposed to the atmosphere. In an oxygen-poor substrate, oxygen is absorbed directly from the atmosphere. In the black mangrove, these aerial roots, termed pneumatophores, occur as direct upward extensions of the subterranean root system. 20 such as occupants of seagrass meadows (including the turtle grass itself), and mangrove mud banks and stilt roots, were killed during the long exposure to desiccation. Estimates indicate that more species of algae and invertebrates, and much more living matter (biomass), were destroyed during those days of June than during two hurricanes combined (Fifi, 1974; Greta, 1978). Collaborating eco-physiologist Joan Ferraris, Mt. Desert Island Biological Laboratory, is examining a number of organisms (sponges, sipunculan worms, shrimps, crabs) that are exposed to strong salinity- temperature stress in their natural environment. Results so far show a fine correlation between experimental tolerances in the animals and range of variability of stress factors in their natural habitat. In the case of sponges, regulatory mechanisms controlling water-ion balances are still unknown, but in the absence of organs, they must take place inside individual cells. Unfortunately, the intertidal swamp is not only an exciting biological study zone, but also a gallery of pollutants. Even in this remote location every imaginable piece of floating debris discarded by man can be found, washed in by currents among the mangrove roots and deposited by the receding tides. Mangrove Forest Above the Tide Unlike the adjacent marine systems, the above-water flora and fauna of the mangrove-covered islands appear less complex and diverse. From the water, an unbroken, monotonous barrier of red mangrove trees confronts, and frequently intimidates, the casual explorer. The species composition of the above-water plant community around Twin Cays is relatively simple. Three halophytic* tree species, known collectively as mangroves, dominate the natural vegetation on most of the islands: Red mangrove (Rhizophora), black mangrove (Avicennia), and white mangrove (Laguncularia). On cays with slightly higher ground, additional woody and herbaceous (soft- stemmed) halophytes are associated with the mangrove, such as buttonwood (Conocarpus), saltwort (Baf./s), and sea purslane (Sesuv/um). In general, mangrove forests have well- defined horizontal zonation. On these mangrove islands, the seaward and channel margins typically are fringed by dense, 4- to 10-meter-tall stands of red mangrove. Behind this fringe, the red mangrove is usually more open and shorter, with black and white mangroves intermixed. The zonation is easily recognized: dull gray-green spires of black mangrove, and flattened, yellow-green crowns of white mangrove stand slightly above and behind the dark green dome of the fringing red mangrove. The interiors of some of the larger islands off Belize, like Twin Cays, have several extensive, unvegetated mud flats and shallow ponds. * A plant growing in salty soil or salt water, termed a halophyte, has unique physiological characteristics that enable it to obtain fresh water, excrete salt, and reduce fresh water loss. Numerous stumps throughout the mud flats are evidence that the trees that once grew there fell victim to some environmental stress. The red mangrove trees growing around the margins of the mud flats and in the ponds are severely stunted and widely spaced. Over the years, these natural bonsai have been distorted and pruned by their environment into fantastic forms, seldom more than 1.5 meters tall. The above-water fauna on the cays is considered by most investigators to be introduced from the Belizean mainland. Even on the largest mangrove islands, most of the "land" is intertidal; therefore, the only environments available to terrestrial animals are arboreal. The fauna is limited to birds, lizards, snakes, snails, and arthropods, such as land crabs, spiders, and insects. These animals probably reached the cays from the mainland by flying, or rafting on or in pieces of wood and other floating debris. A few land bird species have established permanent breeding populations on the mangrove islands. Warblers, vireos, hummingbirds, cuckoos, grackles, and white-crowned pigeons are among the permanent residents. Several of the islands also provide nesting sites for ospreys. These birds frequently build their nests atop tall snags of black mangrove. At Twin Cays, the green-back heron is the most commonly observed wading bird. It breeds on the island, and builds its twig nest in the red mangrove fringe along the channels. It is frequently seen diving for small fish in the shallow, interior ponds. The most conspicuous birds of the area are the brown pelican and frigatebird, which fly overhead or perch in mangrove trees. Insects are, by far, the most diverse and abundant group of above-water animals inhabiting the Belizean mangrove cays. Ants, in 28 or so species, are clearly the most abundant. Termites, because of their huge nests and extensive covered walkways, are the most conspicuous. Some major groups of insects, such as bees, are poorly represented in mangrove fauna. As is other tropical ecosystems, a large percentage of the insect species that we have found associated with mangroves are undescribed. Conclusions The red mangrove fringe, the specialized vegetation, the physical environment, and the associated fauna and flora form a complex and diverse island community above water as well as below. We have learned that mangroves produce fine sediments and organic detritus, and stabilize them by modifying the wave and current regime of the open lagoon. The inventory of species has yet to be completed, but already we have shown that most phyla are represented by species of which 10 to 25 percent, and in some cryptic (having a hidden or concealed lifestyle) microscopic-sized groups, up to 60 percent, are undescribed. The mangrove swamp is rich in recycled nutrients and high in production rates, but its occupants are severely stressed by factors such as text continued on page 24 21 A Gallery "Boston Bay," Twin Cays. In the foreground are prop roots of red mangroves (Rhizophora). (Photo by K. Rutzler) Stinging sea anemone (Bunodeopsis) on turtle grass. (Photo by C. Miller) Black mangrove (Avicennia) pneumatophores. (Photo by M. Parrish) Sponges, ascidians, and anemone on a submerged root. (Photo by K. Rutzler) Clapper rail. (Photo by S. Canupp) of Mangrove Life Seahorse (Hippocampus). (Photo by C. M/7/er) ?•' •''<'• ' /"' j^fti'* Mangrove oysters (Isognomon). (Photo by K. Rutzler) Young upside-down jellyfish (Cassiopea) on mud bottom. (Photo by K. Rutzler) Starfish (Oreaster). (Photo by K. Rutzler) Drift goods deposited by the tides under black mangroves. (Photo by M. Parrish) Carrie Bow Cay Field Station /\ small field station located just behind the barrier reef in Belize has served as a base for research by the Smithsonian Institution and other scientists since 1972. The facility has been made possible largely through the generosity of the Bowman family, whose members have lived in the Stann Creek District of Belize for several generations. Being naturalists in their own right, the Bowmans were easily convinced to dedicate part of the island to research on the biology and geology of Belize's barrier reef. Since its founding in 1972, the National Museum of Natural History's coral reef field station has undergone continuous improvements. Some changes were necessitated by research requirements, others by the devastating effects of hurricanes Fifi (1974) and Greta (1978). The original buildings on the small island of Carrie Bow (at present, about 0.4 hectares, or 1 acre), consist of an old plantation house, carried disassembled across from the mainland, and two smaller cottages. During most of the 1970s, the small cottages and parts of the big house provided sleeping space for only six persons, and necessitated combining the laboratory and workshop into a single room. A small kitchen provided cooking space. Electricity supplied by a small portable generator was limited to short periods during the day and evening. After damage from hurricane Greta in 1978, the laboratory cottage had to be rebuilt. It was enlarged by adding a second story, thus providing additional sleeping space and allowing the research laboratory and workshop areas to be separated. The old outdoor aquarium system with low-volume seawater flow was improved by increasing capacity and enclosing the area with wood siding and windows to protect it from the weather. In 1 985, a new agreement with the Bowman family allowed expansion of living and laboratory space to the upper level of the big house. The resulting renovations added badly needed dry space for instruments, library, and computer. At the same time, the smallest cottage was replaced by a better designed, larger building serving as a dormitory, and a new, separate, and sound- isolated compressor and generator house was built. Other renovations include boat moorings, water tanks and showers, kitchen, and replacement of all electric wiring and fixtures. Some new equipment was added, such as a 4-kilowatt diesel generator, two new 5-meter dive boats, two microscopes, a centrifuge, an electronic balance, air and water filtration systems, and two propane-gas refrigerators. To improve safety, the boats were provided with radiophones compatible with the station's main radio, and a radio-telephone line was established to the Royal Air Force Helicopter Detachment in Belize City, who helped develop logistics for emergency evacuation in case of a diving accident. Plans for 1988 call for an increased seawater capacity with larger pumps, a solar power system, and a 6,000-liter storage tank, and for improved water quality by extending the water intake pipe to the fore reef. Finally, in step with the upscaled mangrove study, we established a self-contained weather station in Twin Cays, 4 kilometers to the northwest. Meteorological and oceanographic sensors are automatically scanned every half hour, and data sent via radio to a portable computer on Carrie Bow Cay. By mid-1988, transmitted data will also be received at the International Airport, Belize, for evaluation and use by the Meteorological Office. — Klaus Rutzler, and Mike Carpenter continued from page 21 salinity and temperature fluctuations, desiccation potential, abundance of fine sediments, and shortage of firm substrates. Space, from the sea bottom to the tree tops, is distinctly partitioned by the animals that exploit this specialized plant community. These intertidal islands, because of their isolation from the Belizean mainland, provide us with ideal locations to study pure mangrove communities in the Caribbean. Klaus Rutzler is Curator of Lower Invertebrates and Program Director of Caribbean Coral Reef Ecosystems (CCRE), National Museum of Natural History, Smithsonian Institution, Washington, D.C. Candy Feller is a freelance scientific illustrator, presently based in McAlester, Oklahoma. Acknowledgment The study described in this article is supported by grants from the Exxon Corporation, the Smithsonian Scholarly Studies Program, and the Smithsonian Women's Committee. Selected References Lugo, A. E., and S. C. Snedaker. 1974. The ecology of mangroves. Annual Review of Ecology and Systematics 5: 39-64. Macnae, W. 1968. A general account of the fauna and flora of mangrove swamps and forests in the Indo-West-Pacific Region. Advances in Marine Biology 6: 73-270. Odum, W. E., C. C. Mclvor, and T. ). Smith, III. 1982. The Ecology of the Mangroves of South Florida: A Community Profile. FWS/OBS- 81/24, 144 pp. Reprinted September 1985. Washington, D.C.: U.S. Fish and Wildlife Service, Office of Biological Services. Tomlinson, P. B. 1986. The Botany of Mangroves. 413 pp. Cambridge, England: Cambridge University Press. 24 Petroleum Pollution > ^ , < ^o*te*» *w -^ *£ - i+M* ^^cijdi Lump', ot tar found on the exposed portion of a reef ofl the southwest coast of Puerto Rico. Shovel is for scale. (Photo by lorge Corredor, University of Puerto Rico) in The Caribbean by Donald K. Atwood, Fred J. Burton, Jorge E. Corredor, George R. Harvey, Alfonso J. Mata-Jimenez, Alfonso Vasquez-Botello, and Barry A. Wade I he title for this article, by its very existence, presumes a problem. That is, if one writes about petroleum pollution in the Caribbean, there must be some. Such a presumption contradicts perceptions of the Caribbean as an area of idyllic islands surrounded by clear, warm seas and beautiful, fringing reefs. Does such pollution exist? If so, where does it come from, what effects does it have, and what were the reasons for investigating its existence in the first place? 25 We will answer the last of these questions first, and because of its obvious oceanographic connection, we will include the Gulf of Mexico in our considerations.* In 1976, the Intergovernmental Oceanographic Commission (IOC) in Paris, the United Nations Environment Programme (UNEP) in Nairobi, Kenya, and the United Nations Food and Agriculture Organization in Rome, all of which have interests in the Caribbean/Gulf of Mexico (or "American Mediterranean," as this area is often called), convened a meeting of scientists from that region in Port of Spain, Trinidad, to discuss what needed to be done regarding a growing concern over marine pollution. Although this group recognized numerous local pollution problems in the region (for example, lack of sewage treatment facilities for coastal urban centers, and agricultural runoff), their report, as published by the Intergovernmental Oceanographic Commission (IOC) in Paris (see Selected References), noted that petroleum pollution was of region-wide concern, and recommended that the organizations present initiate a research and monitoring program to determine the severity of the problem and monitor its effects. CARIPOL Two of these agencies, the IOC and UNEP, followed up on this recommendation. The IOC worked cooperatively with a Steering Committee of regional scientists to design a program that would 1) provide necessary information, and 2) allow laboratories from throughout the region to participate without expensive, sophisticated equipment. UNEP provided funds to train participants, and for symposia to present, discuss, and publish the results. The program was named CARIPOL, for CARIbbean POLlution research and monitoring, and the Steering Committee designed a program to monitor three parameters related to petroleum pollution: • Tar on beaches. Tar to be collected from the water line to the back of the beach along 1 -meter transects, weighed, and reported as grams of tar per meter of beach front. • Floating tar. One-meter-wide neuston nets (designed to skim the ocean surface, sampling the upper few centimeters) to be towed from a vessel outside the vessel wake for a known time and vessel speed. The tar collected to be weighed and reported as milligrams of tar per square meter of sea surface. • Dissolved/dispersed petroleum hydrocarbons (DDPH). One-gallon samples to be collected in carefully cleaned, small-mouth bottles suspended on a 1 -meter tether from a surface * Throughout this issue of Oceanus, "the Caribbean" is defined as the waters and countries of the Caribbean Basin — the Lesser Antilles, Greater Antilles, countries bordering the western and southern rim, and the Caribbean Sea. In this article, because of oceanic and geographic links, the scope is expanded to what is sometimes termed the "Wider, or Greater Caribbean" — a designation that includes the Gulf of Mexico and parts of Florida. float. The petroleum to be extracted from this sample using nanograde (ultrapure) hexanc, and the amount extracted to be estimated using a technique called ultraviolet spectrofluorescence. A compound called chrysene (similar to the most toxic constituents in petroleum) to be used as the standard for this measurement. In the summer of 1979, some of the region's worst fears regarding petroleum pollution were realized when a well drilled by the Mexican government's national petroleum company (PEMEX IXTOC-1) blew out in the southern Bay of Campeche (in the southern Gulf of Mexico), and became the greatest single oil spill in history. In September of that year, and in the face of the IXTOC disaster, governments in the region, which had agreed to participate in CARIPOL, sent scientists and technicians to the University of Costa Rica in San Jose to be trained in making the standard CARIPOL observations. Training was conducted in both English and Spanish, and detailed method manuals were published in both languages. By 1980, the program was operational, and data were being reported to a central facility operated by the U.S. National Oceanic and Atmospheric Administration (NOAA) in Miami, Florida. Figure 1 shows the region throughout which data were collected, as well as the countries that participated. During the following six years, CARIPOL participants provided data on more than 9,000 observations throughout the region. Participants varied from national park rangers in Bonaire who sampled beaches to university professors in Costa Rica, Cuba, Jamaica, Mexico, Trinidad, the United States, and Venezuela to naval personnel in Colombia. The data set collected was the largest and most complete in the world, and allowed some significant conclusions regarding the status of petroleum pollution in the Wider Caribbean and its effects. Tar on Beaches CARIPOL participants provided significant amounts of beach tar data from throughout the region (Figure 2). Although the scale in Figure 2 prevents good resolution of the data in many locations (especially for more than 5,000 data points in Trinidad and Tobago), the figure clearly indicates that 1) there are substantial data through much of the region (there is a noteable lack in the northern Gulf of Mexico), and 2) the problem of beach contamination by tar is serious in many locations, with numerous beaches having average concentrations in excess of 100 grams per meter of shore front. Experience throughout the region indicates that when beach tar values reach 10 grams per meter, persons using the beaches commonly get tar on their feet. At values approaching 100 grams per meter, the beach becomes virtually unuseable for tourist purposes. Given the fact that many of the region's economies depend extensively on tourism, the high incidence of contamination in excess of 100 grams per meter is a serious problem. The high concentrations of tar on beaches in the southern Bay 26 CAYMAN ISLANDS „ DOMINICAN REPUBLIC MEXICO -^N GUATEMALA> JAMAICA PUERTO RICO COSTA Rl ST. LUCIA% CURACAO BONAIRE BARBADOS p v GRENADA "TRINIDAD & TOBAGO GUAYANA COLOMBIA Figure 1 . The Caribbean pollution research and monitoring (CARIPOL) area, with participating countries identified. of Campeche and the east coast of Yucatan in Mexico, the southeast coast of Florida, the Cayman Islands, the area near Kingston Harbor in Jamaica, Curacao, and beaches on the windward side of islands such as Barbados, Grenada, Trinidad, and Tobago are of special concern. In fact, windward coasts are seriously contaminated throughout the region as evidenced in Figures 3 (Trinidad and Tobago), and 4 (the Florida Peninsula). In each of these cases, beaches exposed to the prevailing southeast trade winds are significantly more contaminated than beaches on the leeward side of the landmass. This is interpreted as evidence that the source of much of the tar is upwind throughout the region, and clearly the result of factors beyond the control of the individual governments involved. Beach contamination is particularly serious in Grand Cayman, where there is no domestic petroleum activity. However, this island is located in an area adjacent to heavy tanker traffic that moves through the Yucatan Strait and Windward Passage. In several areas, beach pollution levels have been serious for many years. In Florida, for example, a comparison of recent results to studies by the Figure 2. Average concentrations of beach tar in grams per meter of beach front for each site sampled in the CARIPOL petroleum pollution monitoring program. The average concentration at each sample site is shown as a shaded circle. 27 KEY 100 >1000 Figure 3. Average concentrations of beach tar at sampling sites in Trinidad and Tobago. Concentrations are depicted by shaded circles. American Petroleum Institute in 1959 and 1974, indicates that the level of contamination on southeast Florida beaches has been about the same since 1958. Thus, despite continuing concerns, as expressed in continuing newspaper accounts in southeast Florida, levels of beach tar contamination have changed very little during the last 30 years. Floating Tar The CARIPOL data base on floating tar, with 681 records, is the smallest of the three parameters measured. The major portion of these data were taken in the Gulf of Mexico in programs conducted by Mexico (Universidad Autonoma de Mexico) and the United States (University of South Florida and NOAA) (Figure 5). Some very pertinent points can be made using these data when considered in the light of regional current patterns. Figure 6 is a composite plot of satellite-tracked buoy trajectories in the Caribbean Sea and Gulf of Mexico in 1975 and 1976 (as measured by a group headed by Robert L. Molinari of NOAA's laboratory in Miami). Superimposed on the buoy tracks is a schematic depiction of the average position of the major flow through the system. This flow enters through the southeastern passes of the Lesser Antilles arc, moves through the Caribbean as the Caribbean Current, traverses the Eastern Gulf of Mexico as the Gulf Loop Current, or Loop Intrusion, and exits through the Straits of Florida (between Florida and Cuba) as the beginnings of the Gulf Stream. At times the Loop Current "pinches off" just north of the Straits of Yucatan and becomes an eddy that moves westward through the Gulf while the major flow exits directly through the Straits of Florida until the Loop Current is "rebuilt." Floating-tar concentrations are higher in the Loop Intrusion and southern Straits of Florida than in adjacent areas. Similar high concentrations exist in the Eastern part of the Caribbean coincident with the average Figure 4. Average concentrations of beach tar at sampling sites along the coasts of the U.S. Florida peninsula. Concentrations are depicted by shaded circles. 28 Figure 5. Average concentration of floating tar in milligrams per square meter for each 1 -degree square for which CARIPOL data exist. The average concentration for each square is shown as a shaded circle in the middle of that square (thus, some circles appear on land). position of major east-west flow in that area. Scientists at NOAA's Miami laboratory analyzed floating tar data collected by the United States in the Gulf of Mexico and Straits of Florida and similarly concluded that floating tar concentrations are significantly higher within the Loop Instrusion and the Southern Straits of Florida. Comparison of floating tar concentrations in the CARIPOL data base to those observed in the 1970s in global IOC program on petroleum pollution monitoring, called Marine Pollution Monitoring Program for Petroleum (MAPMOPP), show that where overlap occurs between the CARIPOL data and the relatively sparse MAPMOPP data in the region, average concentrations are very similar. This demonstrates that 1) data from the two programs compare very well and 2) the situation probably has not changed significantly during the last decade. Dissolved/Dispersed Petroleum Hydrocarbons The CARIPOL data base contains 1,464 records for dissolved/dispersed petroleum hydrocarbons (DDPH). The data are plotted in Figure 7. The results of a careful intercalibration exercise, held at the itDOO O O ® © fl> OO f C/O G> O O©O Bermuda Biological Station in St. George's, Bermuda, in 1985, indicate that values greater than 0.1 microgram per liter can be considered significant. Based on experience within the Wider Caribbean, including experience in the Bay of Campeche during the 1979 IXTOC-1 oil well blowout, the background level for DDPH in the Gulf of Mexico seems to be best stated as 1 to 10 micrograms per liter. This is borne out by Figure 7, where the majority of the values shown are greater than 1 .0 micrograms per liter, with many values near Yucatan and in the Gulf of Mexico greater than 10.0 micrograms per liter. This Gulf of Mexico background level is more than an order of magnitude higher than the 0.1 to 0.2 micrograms per liter observed during the 1970s MAPMOPP program for areas that were not obviously contaminated, and for which a reasonable statistical sampling existed— for example, the Western Pacific and parts of the Mediterranean. If we accept the MAPMOPP data as correct, and there is no reason not to, we must conclude that the Gulf of Mexico is significantly contaminated with DDPH relative to "clean" areas sampled in the Figure 6. Composite plot of satellite-tracked buoy trajectories collected in the Caribbean Sea and Gulf of Mexico from October 1975 to lune 1976. The heavy dashed line represents the major flow through the system when the Gulf Loop Current is intact in the Gulf of Mexico. I @ © ©j®-4SNiN9 V® @®®@ ( ®m © © © ® © © / ® ® ^H-®-©11© 4® MAPMOPP study. This is particularly true in the numerous locations where average values exceed 10 micrograms per liter. Contamination is not obvious for the Caribbean Sea itself from the CARIPOL data set, except for the east coast of Yucatan, and the area near Kingston Harbor in Jamaica. However, the extent of CARIPOL sample coverage for DDPH in the Caribbean is sparse. NOAA/Miami scientists during their analysis of floating tar and DDPH data for the Gulf of Mexico and Straits of Florida, as part of this CARIPOL study, showed significantly higher DDPH values for the Southern Straits of Florida — just as they had for floating tar. They also showed that, for the regions they examined, the average values of DDPH and floating tar covaried — that is, when one was high for a region, so was the other. Ocean waters contain populations of bacteria capable of metabolizing petroleum, which, when presented with quantities of petroleum, rapidly grow and consume the oil. Thus, the high level of DDPH contamination in the Gulf of Mexico is an indication that these bacteria are not able to remove it faster than it is replenished. This in turn indicates that there is a constant, fresh input of DDPH to this area. Sources of Petroleum Contamination In an effort to identify probable sources of the petroleum contamination documented above for the Wider Caribbean, it is beneficial to review major observations made in the regional monitoring of beach tar, floating tar, and DDPH. They are as follows: •Windward exposed beaches throughout the region from Barbados to Florida are heavily contaminated with tar relative to leeward exposures. •Surface waters of the major east-to-west flow in the region, that is, the Caribbean Current, the Gulf Loop Intrusion, and the Straits of Florida contain significantly more floating tar than adjacent areas. •Waters of the Gulf of Mexico and those south of the Yucatan Strait are chronically Figure 7. Average concentration of dissolved/dispersed petroleum hydrocarbons (DDPH) in micrograms per liter (or each 1 -degree square for which CARIPOL data exist. The average concentration for each square is shown as a shaded circle in the center of that square (thus, some circles appear printed on land). contaminated with DDPH at a level an order of magnitude higher than that measured in uncontaminated areas during the 1970s MAPMOPP project. This chronic, high level of DDPH is an indication that there is a constant, fresh input of petroleum to these waters. •Highest levels of petroleum contamination in the region exist within, and adjacent to, waters with extensive petroleum tanker traffic, for example, the Cayman Islands and the Straits of Florida. In addition to these regional observations we can add some very pertinent findings from individual country programs as reported at the CARIPOL Petroleum Pollution Monitoring Symposium held in La Parguera, Puerto Rico, in December 1985. These are as follows. Julio Morell and Jorge Corredor of the University of Puerto Rico reported a time series of floating tar observations off the Southwest coast of Puerto Rico in which the level of contamination dropped significantly as tanker traffic from a nearby petroleum refining complex declined. These scientists concluded that at least 50 percent of the variability in their data can be explained by variations in tanker traffic. Fred J. Burton of the Mosquito Research and Control Unit on Grand Cayman reported the high levels of contamination on and near Grand Cayman, Cayman Brae, and Little Cayman Islands, which are all adjacent to major tanker routes. Studies using sophisticated-techniques called "ultraviolet fluorescence excitation/emission," and "glass capillary gas chromatography" in examination of tar found on beaches of these islands indicated that 80 percent of the samples examined had a crude oil source with spectra similar to Arabian and/or Alaskan crudes. In cooperation with local airline pilots, Burton also documented the existence of slicks near the Cayman Islands. Twelve such slicks were documented. All were narrow (about 0.5 kilometers wide) and long (up to 100 kilometers). In three cases, these slicks were observed as being released from 30 ships, two of which were tankers either cleaning tanks (February 1982), or discharging ballast (October 1985). All 12 slicks were sighted in the early hours of daylight, indicating that releases were occurring at night. Additionally, a decline of beach contamination on Cayman Brae and Little Cayman was noted when oil transshipment operations near these islands virtually ceased in 1982. Barry A. Wade and graduate students at the University of the West Indies, Kingston, Jamaica, campus used techniques similar to those used by Burton. They demonstrated that most contaminating oil found on the South coast of Jamaica was similar to Venezuelan crude oil, which is the crude most commonly imported into Jamaica. Interestingly, oil on Jamaican beaches with a northeast exposure did not exhibit these characteristics, indicating that oil on these beaches had a different origin. The rate of tar arrival on south coast beaches was estimated at 1.4 grams per meter per day, but at times of "documented near-shore tanker washing," this could reach 400 grams per meter per day. The authors concluded that the principal source of tar contamination was illegal ballast washing and discharge from tankers. Edward Van Vleet of the University of South Florida in Tampa demonstrated that pelagic tar levels in the eastern Gulf of Mexico and Straits of Florida were substantially higher than in most other areas of the world, and that as much as 50 percent of this tar entered these areas from the Caribbean through the Yucatan Strait. Gas chromatographic analyses of this pelagic tar showed that 50 percent of the floating tar had chemical characteristics diagnostic of tanker ballast washings. This lead to the conclusion that 50 percent of the pelagic tar in these areas was from tanker discharges. Given the above observations, we conclude that as much as 50 percent of the floating tar and beach tar throughout the Wider Caribbean region comes from the adjacent North Atlantic gyre system, and is carried to and through the region by the prevailing winds and currents. The fact that the 1970s MAPMOPP data show high floating tar concentrations in the adjacent North Atlantic supports this conclusion. However, there is obviously significant fresh input of petroleum directly in the region, as evidenced by the chronically high DDPH levels. Correlation of high floating tar and beach tar levels with petroleum tanker operations, and the unique gas-chromatography profiles of 50 percent of the floating tar in the eastern Gulf of Mexico and Straits of Florida, shows that most of this fresh input is from petroleum tanker ballast washings. The remainder is probably from petroleum drilling and production operations, for example the PEMEX operations in the Bay of Campeche, as well as from natural seeps. As noted previously, the southeast Florida level of beach tar contamination has been about the same for 30 years. There are a number of possible explanations for this. One is that despite increasing success at controlling release of petroleum from tankers, tanker traffic in the area has increased so much that the level of pollution is still the same. Another, less plausible explanation is that beach CARIPOL scientists recovering a neuston net towed at the sea surface to sample for floating tar. (Photo by lorge Corrector, University of Puerto Rico) contamination in the late 1950s was the result of ships sunk during World War II (1940 to 1945), which were still breaking up, thus releasing the petroleum trapped in their hulls. In this scenario, the present high pollutant levels result from existing tanker traffic. Effects of Petroleum Contamination There are clearly adverse effects from the petroleum contamination existent in the Wider Caribbean. One obvious effect is the serious soiling of beaches in an area where tourist use of these beaches is important to state economies. This is a problem throughout the region. In southeast Florida, beaches are continually cleaned to allow tourist usage — with a secondary result of increased beach erosion. It is clear that any tourist development on windward exposed beaches in the region will have a significant tar problem. Floating tar has adverse effects other than when it is blown ashore on beaches. University of South Florida scientists, Edward Van Vleet and G. Pauly, in results presented in a CARIPOL Symposium in 1985, analyzed internal organs and feces from threatened and endangered marine turtles collected around Florida. Results indicate that these turtles feed on floating oil, and that this oil may remain in the turtles' digestive tracts for several days. Tar scraped from the mouths of many of these turtles had the same chemical characteristics as that of tanker ballast washings. They also noted that the highest incidence of stranding of dead sea turtles in Florida is along the southeast Florida coast, an area 31 adjacent to the heavily contaminated Florida Straits, and coincident with the highest concentrations of beach tar in the entire Florida Peninsula. The effects of DDPH are not as readily documented. The IXTOC-1 blowout experience showed that the gross contamination from that event was largely assimilated by the system through such processes as bacterial degradation and chemical degradation as the result of sunlight. However, then, as now, it was observed that the Gulf of Mexico background of DDPH was in the range of 1 to 10 micrograms per liter, that is at least an order of magnitude greater than that observed in uncontaminated areas during the 1970s MAPMOPP study. This chronic exposure to the most toxic portion of petroleum, polycyclic aromatic hydrocarbon (PAH) is probably affecting marine life. For example, numerous studies have been made on an enzyme system response to PAH exposures in marine organisms. One recent study conducted by J. M. Davies, J. S. Bell, and C. Houghton (as reported in Marine Environmental Research in 1984) examined fish caught at various distances from North Sea oil drilling operations, where oil-base muds were used, and drill cuttings discarded over the side at the drilling sites. Sediments within 1 .0 kilometer of these sites had total PAH concentrations of about 10,000 nanograms per gram, which we estimate would cause water column exposures no greater than that observed in the Gulf of Mexico. Their results show a statistically significant enhancement of enzyme oxidation of ingested hydrocarbons in two fish species (cod and haddock) caught in sediment contaminated areas, as opposed to clean areas. The authors interpret this result as evidence that the contaminating oil is biochemically available to these fish, resulting in a response of the fish enzyme systems. They point out that such enzyme response has been inversely correlated with reproductive success in flatfish along the coast of California. Summary • A significant level of petroleum pollution exists throughout the Wider Caribbean. Manifestations of this pollution include serious tar contamination of windward Attention Teachers! We offer a 25-percent discount on bulk orders of five or more copies of each current issue— or only $4.00 a copy. The same discount applies to one-year subscriptions for class adoption ($17.00 per subscription). Teachers' orders should be sent to Oceanus magazine, Woods Hole Oceanographic Institution, Woods Hole, MA 02543. Please make checks payable to W. H.O.I. Foreign checks should be payable in dollars drawn on a U.S. bank. exposed beaches, high levels of floating tar within the major currents system, and very high levels of dissolved/dispersed hydrocarbons in surface waters. • The sources of petroleum pollution in the region include oil entering from the adjacent North Atlantic (50 percent) and tanker ballast washings (50 percent). • Effects of this petroleum pollution include: 1) tar levels on many beaches that either prevent recreational use, or require expensive clean-up operations, 2) probable distress and death to marine organisms, such as endangered turtles who feed on floating tar; and 3) responses in the enzyme systems of marine organisms that have been correlated with declines in reproductive success. The authors of this article comprise the Steering Committee for the CARIPOL Program. Donald Atwood is Director of the Ocean Chemistry Division of NOAA's Atlantic Oceanographic and Meteorological Laboratory in Miami, Florida, and George Harvey is a Senior Oceanographer in that Division. Fred Burton is Director of the Mosquito Research and Control Unit and Natural Resources Study for the Cayman Islands, lorge Corredor is an Associate Professor of Chemical Oceanography in the Department of Marine Sciences of the University of Puerto Rico (Mayaguez), and is presently on sabbatical leave working with the United Nations Environment Programme (UNEP) in Nairobi, Kenya. Alfonso Mata-limenez is Dean of Sciences for the University of Costa Rica in San lose (San Pedro), Costa Rica. Alfonso Vasquez-Botello is a Professor at the Institute for Marine and Limnological Sciences at the Autonomous University of Mexico, in Mexico City, Mexico, and is on temporary detail to the Regional Coordinating Unit for the UNEP Caribbean Action Plan in Kingston, lamaica. Barry A. Wade is a senior executive with the Petroleum Corporation of lamaica. Acknowledgments This article is an adaptation of a scientific paper originally published in Marine Pollution Bulletin. The authors acknowledge the indispensable assistance of Messrs. William Nodal and Stephen Loewenthal, who wrote the essential computer programs for data archival and display, and of Ms. Cindy Foltz, Ms. Roxanne Caballero, and Ms. Helen Cummings, who so diligently looked after the actual archival and generation of data products. Selected References Atwood, D. K., and R. L. Ferguson. 1 982. An example study of the weathering of spilled petroleum in a tropical marine environment: IXTOC-1. Bull, of Mar. So. 32(1), 1-13. CARIPOL. 1980. CARIPOL Manual for Petroleum Pollution Monitoring. Miami, FL: Atlantic Oceanographic and Meteorological Laboratory. Reinburg, L., jr. 1984. Waterborne trade of petroleum and petroleum products in the Wider Caribbean Region. Report No. CG-W- 10-84, U.S. Department of Transportation, United States Coast Guard, Office of Marine Environment and Systems. Available through the National Technical Information Service, Springfield, MD. Van Vleet, E. S., W. M. Sackett, S. B. Reinhardt, and M. E. Mangini. 1 984. Distribution, sources and fates of floating oil residues in the Eastern Gulf ot Mexico. Mar. Poll. Bull. 15: 106-110. 32 Caribbean Marine Resources: A Report on Economic Opportunities by A. Meriwether Wilson /Viarine resources in the Caribbean Basin are being overlooked, undervalued, and even destroyed at an alarming rate. Historically, these resources have provided a livelihood for many people in the region, as well as revenue to the islands whose shores are surrounded by this complex body of water. But today, as many of these resources are in jeopardy, information, particularly about the economic potential, is needed — as all Caribbean nations face important policy decisions on the use and development of their marine resources. Recognizing the urgent need fora balanced and sustainable development of Caribbean marine resources, the U.S. Agency for International Development (USAID) and the U.S. National Oceanic and Atmospheric Administration (NOAA) recently completed a joint study entitled "Caribbean Marine Resources: Opportunities for Economic Development and Management." The report from the study, summarized in this article, gives projections for potential marine resources that could support economic advancement of the Caribbean Basin countries. It also reports on the present status of known resources. Regional Overview Nearshore Marine Habitats. The Caribbean Sea and many other tropical marine areas are a study in complex relationships. Coastal waters generally contain some of the world's most diverse and productive ecosystems, including coral reefs, seagrass beds, and mangrove forests. Through internal energy recycling mechanisms, these ecosystems manage to overcome the nutrient limitations of the relatively sterile tropical offshore waters. One example of the complex relationships in tropical environments is that of the stony coral animals, which are responsible for building the limestone (calcium carbonate) reefs. These reefs form major parts of the bases, or platforms, of many of the Caribbean islands. The secretion of calcareous materials by these coral animals is enhanced by a unique symbiotic relationship between the host animal and a microscopic algae (zooxanthellae), which lives in the coral itself. Being plants, the latter algae require sunlight, and therefore clear waters, for growth. Mangroves (see article page 16) and seagrass beds are dependent on nutrient sources from in situ organic decay and nearby rivers. It is this delicate physical, chemical, and biological linkage that creates and maintains these ecosystems, which in turn become resources for human use. Mangroves are nursery and breeding grounds for invertebrates, fishes, and birds; reefs are sources of sand for tourism, and also act as protective barriers during storms. Too often the importance of understanding these linkages and maintaining these habitats in their entirety is overlooked when assessing a marine habitat for its economic value and resource development potential. These marine habitats are under constant stress from the very development activities that, ironically, form the crux of the economic opportunities for developing these resources. For this reason, a balanced approach is needed for determining human impacts on ecosystems, and in turn, the impacts of resulting environmental change on human health. Tourism, fisheries, shoreline and harbor construction, upland forestry, and agricultural activities are some of the major factors that affect nearshore habitats. When these activities are carried out without ecological consideration and caution, chemical pollution, sediment loading, and coastal erosion occur, which in turn may lead to loss of species, including humans, and entire habitats. Opportunities for developing ecologically and economically sound nearshore resource activities include tourism (discussed here as a separate resource), marine protected areas, endangered species, harbor and port development, and fisheries enhancement. To manage resources based on ocean, coastal, and upland development projects, there needs to be a framework of governmental and institutional support. 33 Capture Fisheries and Mariculture. Fisheries resources include conch and lobster (exportable at high prices), offshore game fish, and mariculture opportunities — such as crabs, clams, and seaweeds. Most Caribbean fishery activities take place in nearshore areas, are small-scale in nature, and are carried out by local people for daily subsistence. There are nearly 200 species of different reef finfish in some nearshore areas, presenting a multi- species resource with capture and management requirements that are different from the single- species resources that dominate open-ocean and temperate environments. Tropical fisheries vary greatly between environments. The small volcanic islands with narrow submarine shelves have limited nearshore fishery resources, while the Central and South American coasts, with wide continental shelves and increased nutrient resources from river runoffs, have more potential for higher yields. The nature of a fishery industry in the Caribbean is closely related to the type of technology available. Many subsistence fishermen use canoes or sailboats with outboard motors. While there are increasing recommendations to advance the technology for locating and capturing fishery resources, this is often what creates the demise of a particular resource. The overexploitation of targeted species — for example, lobster, conch, and tuna— and the lure of higher paying jobs in the service sector have turned fishing into a part-time activity for most Caribbean fishermen. There are a few large- scale operations that exploit offshore species. These, however, are generally capital intensive, require larger vessels, and have extensive marketing and processing needs. These needs include being near urban ports or centers — a condition that is limited in the Caribbean (see articles pages 57 and 65). As the nearshore fisheries are depleted through inadequate ecological knowledge, poor management, coastal and seaborne pollution, and habitat degradation, the need for high-quality protein for both the local and tourist markets continues to create pressure to expand offshore fisheries and increase fish imports. Yet these "new" underdeveloped resources will suffer the same fate of inshore fisheries stocks if management controls are not implemented. The overriding constraints on developing fisheries in a sustainable manner include: limited knowledge of fish populations; inappropriate gear and technology; lack of marketing and processing facilities; poor infrastructure; few trained staff at all levels; and low priority in the governmental arena. Ciguaterra, a poison to the human nervous system found in some reef fish, is an increasing problem for both the local and tourist populations. It needs immediate monitoring and research efforts. The culture of marine organisms— mariculture — is being considered as a solution to overfished waters, protein needs, and the need to reduce imports. Those countries with nutrient-rich estuarine bays, lagoons, and mangrove areas are Distribution and status of threatened Caribbean coastal and marine animal species. Species (Common Names) Status Country Monachus tropicalis (Caribbean Monk Seal, West Indian E Seal) Trichechus inunguis (Amazonian Manatee, S. American V Manatee) Trichechus manatus (Caribbean Manatee, N. American V Manatee) Pterdroma hasilata (Black-capped Petrel, Diablotin) V Caretta caretta (Loggerhead Turtle, Tortuga de mar, V Cares, Tartaruga domar, Uruana, Suruana) Chelonia mydas (Green Sea Turtle, Tortuga Verde del E Atlantico and Pacifico, Tortuga Blanca) Eretmochelys imbricata (Hawksbill Turtle, Carey, Tortuga E Carey, Tartaruga verdaderia and de Pente) Lepidochleys kempii (Kemp's Ridley, Atl. Ridley Sea E Turtle, Tortuga Lora) Lepidochelys olivacea (Olive Ridley Turtle, Pacific Ridley E Turtle, Tortugaverde, Parlama) Dermatemys mawii (Central American River Turtle) V Dermochelys coriacea (Leatherback, Leathery Turtle, E Luth, Tortuga Tora, Barriguda, Tarataruga) Caiman crocodilus crocodilus (Spectacled Caiman) V Caiman crocodilus fuscus (Brown caiman) V Crocodylus acutus (Amer. Crocodile, Crocodile, Lagarto E Negro) Ameiva polops (St. Croix Ground Lizard) E Family Anthipathidae (Black Corals) CT Strombus gigas (Queen Conch) CT Panilurus argus, P. guttatus (Spotted Spiny Lobster) CT Mexico, Bahamas Col., Yen. Mex., Bah., Cuba, D. Rep., Haiti, Jam., P. Rico, Trin./Tob., Belize, C. Rica, Guat., Hond., Nica., Pan., Col., Ven. Haiti Mex., Antig./Barbud., Bah., Cuba, D. Rep., Jam., Ne. Ant., P. Rico, Trin./Tob., C. Rica, Guat., Hond., Nica., Pan., Col., Ven. Mex., Antig./Barbud., Bah., Cay. Isl., Dom., D. Rep., Gren., Guad., Haiti, Jam., Mart., Ne. Ant., P. Rico, St. Luc., St. Vin., Trin./Tob., USVI, Belize, C. Rica, Guat., Hond., Nica., Pan., Col., Ven. Mex., Antig./Barbud., Bah., Cay. Isl., Cuba, Dom., D. Rep., Gren., Guad., Haiti, Jam., Ne. Ant., P. Rico, St. Luc., St. Vin., Trin./Tob., USVI, Belize, C. Rica, Guat., Hond., Nica., Pan., Col., Ven. Mex. Mex., Cuba, P. Rico, C. Rica, Guat., Hond., Nica., Pan., Col., Ven. Mex., Belize, Guat., Hond., Pan., Col., Ven. Mex., D. Rep., Grenadines, Guad., P. Rico, Trin./Tob., BVI, USVI, Belize, C. Rica, Nica., Pan., Col., Ven. Trin./Tob., Col., Ven. Mex., Cuba, Nica., Pan., Col., Ven. Mex., Bah., Cay. Isl., Cuba, D. Rep., Haiti, Jam., Ne. Ant., Belize, C. Rica, Guat., Hond., Nica., Pan., Col., Ven. USVI Caribbean Region Caribbean Region Caribbean Region Status Key: E— Endangered; V— Vulnerable; CT— Commercially Threatened; Source: International Union for the Conservation of Nature and Natural Resources/Cambridge Monitoring Centre, 1987 — as cited in Goodwin and Wilson, 1987 (see Selected References). 34 Existing marine parks and protected areas in the Caribbean region. Country Protected Area Name Estab. Hectares (Marine %) Antigua Diamond Reef Marine Park 1973 2,000 — Palaster Reef Marine Park 1973 500 — Bahamas Inagua National Park 1965 74,000 (10) Exuma Cays Land and Sea Park 1958 45,000 (80) Conception Island Land and Sea Park — 810 (80) Union Creek 1965 1,813 — Barbados Barbados Marine Reserve 1980 — (100) Belize Half Moon Cay Natural Monument 1982 4,144 (95) Hoi Chan Marine Reserve 1987 — — British Virgin Islands Wreck of the Rhone Marine Park 1983 323 (96) Colombia Parque Nacional Corales del Rosario 1977 18,700 — Parque Nacional Natural Tayrona 1969 15,000 — Parque Nacional Natural Isla de Salamanca 1969 21,000 — Santuario de Fauna Los Flamencos 1977 7,000 — Costa Rica Cahuita National Park 1970 2,000 (35) Tortuguero National Park 1970 18,947 (16) Dominican Republic Parque Nacional del Este 1975 43,400 — Samana Bay — Silver Banks Marine Sanctuary — — — Honduras Rio Platano Biosphere Reserve 1980 350,000 — Jamaica Montego Bay Marine Park 1959 — — Ocho Rios Marine Park — 278 — Martinique Pare Nature! Regional de la Martinique 1975 — — Mexico Isla Mujeres — — — La Blanquilla — — — Cancun-Nizuc-Isla Mujeres — — — Arrecifes de Cozumel 1980 — — Isla Contony 1960 — — Ria Celestrum 1979 59,000 — Rio Lagartos 1918 47,840 — Netherlands Antilles Bonaire Underwater Park 1983 — (100) Curacao Underwater Park 1983 — (100) Puerto Rico labos Bay/Mar Negro — — — Saint Lucia Maria Islands 1985 — — Pigeon Island 1982 — — Trinidad and Tobago Buccoo Reef and Bon Accord Lagoon 1970 — (100) Caroni Swamp 1982 7,900 — US Virgin Islands Virgin Islands National Park, St. John 1963 6,073 (33) Buck Island Reef, St. Croix 1961 356 (80) Venezuela Parque Nacional Archipelago Los Roques 1972 225,143 — Parque Nacional Mochima 1973 94,935 — Parque Nacional Morrocoy 1974 32,090 — Laguna de Tacarigua 1974 18,400 — Sources: International Union for the Conservation of Nature and Natural Resources, 1982, 1985; M. E. Silva, et al., 1986; Van'T Hoff, 1985 — as cited in Goodwin and Wilson, 1987 (see Selected References). potentially suitable sites for the development of commercially viable mariculture species, such as shrimp, crabs, conch, finfish, and seaweeds. While mariculture at first appears to be a cure-all, there are numerous constraints that have generated a poor success rate for many mariculture projects in the Caribbean. Mariculture requires a high initial investment of time, land, and money. There is a general lack of many of the elements that make up a successful mariculture project. These include adequate biological information on the cultured organisms, sufficient variability of seed and brood stocks, suitable culture sites, and adequate government support. Mariculture projects must also overcome the problems associated with introducing exotic species, new diseases in cultured animals, and numerous import/export regulations. Despite these seemingly overwhelming deterrents, the potential benefits from mariculture strongly support the continued development of projects on a cautious, pilot-scale basis. Geological Resources. Hard minerals (sand, gravel, metal, phosphate, limestone, and salt) and oil reserves are the primary marine geological resources throughout the Caribbean region. The hard mineral resources are important potential low-cost resources, yet there is insufficient information and local technology available to acquire detailed information on their location, quantity, and quality. Petroleum resources are extensive in specific areas of the Caribbean. They are exploited primarily by national and international companies. Although sand and limestone may appear to be ubiquitous resources, the mining techniques and removal of these resources cause some of the most severe impacts on marine resources. Limestone and sand come from the coral and algal banks that form much of the base of most Caribbean islands. As these minerals are dynamited and dredged for construction, there may be damage to adjacent reef habitats through loss of substrate for organisms to grow on. The resulting sedimentation in the water 35 column reduces the amount of penetrating sunlight needed for coral growth. Metal resources include high-value minerals, such as gold, platinum, titanium, and chromium, which are deposited on shelf areas by stream and beach processes. Excavation studies are needed for all of these minerals, to identify source locations, current dynamics, and impacts on adjacent habitats. There also is a need for low-cost, high-resolution seismic profiling studies in those areas of the Caribbean with extensive continental shelves. The Caribbean Action Plan of the United Nations Environment Programme (UNEP) considers petroleum pollution to be a major regional concern (see article page 25). Numerous beaches are polluted from oil spills, and covered with tar, thus making them undesirable for tourism. The impact of oil on marine turtles, birds, and coral reefs is an area of active research. Radar and remote-sensing technologies can provide information on tracing a variety of pollutants such as sediment runoff, sewage, and petroleum. There need to be cooperative programs for information exchange and technological assistance between the regional, academic, and government agencies of developed and underdeveloped countries in the region. Educational Resources. The need for appropriate education, training, and technical support in the Caribbean underlies the development of every resource mentioned in this article. Although there is increasing interest in the marine world, there is too often a focus on the short-term economic benefits rather than long-term resource values. Education is in itself a long-term resource, but one that has immediate opportunities at all levels of schooling and training. Many public and private marine research institutions suffer from a lack of funding, which often results in inadequate instrumentation and poor libraries. Educational opportunities suffer because of the low priority assigned to this resource by governments. The Rosenstiel School of Atmospheric and Marine Sciences at the University of Miami in Florida is in the process of developing a computerized data base and electronic mail network for all published and non-published articles on Caribbean marine resources and environments. This effort should aid countries with limited library facilities. Tourism. The seductive images of surf, sand, and sun have created a multi-faceted tourism industry in the Caribbean. This industry is having an effect on the gross domestic product (GDP) of individual countries, local employment opportunities, and foreign exchange earnings. Yet the development of tourism resources is also producing dire consequences for both the natural environments and the people who use them. The very resources that make up the attractions are being destroyed: examples include coral reefs, sand beaches, and clear waters. All these are subject to intense development pressure from construction activities, sewage pollution, and overfishing. There also are numerous social consequences to a rapid expansion of tourism. Often social values of the local people are restructured and undermined by the financial lures of service-oriented positions. Visitor preferences may change over time as different trends in recreation come into vogue. There are many types of marine-related tourism in the Caribbean, just as there is an array of users to support them; these activities include snorkelingand diving, yachting, tennis and golf, and nature experiences, such as bird and whale watching. There is an increasing interest in the "nature" types of tourism that have a potential to require less intense infrastructure — camping facilities, for example, rather than high-rise hotels. Many countries, however, are not immediately interested in low-tech, smaller-scale recreation projects, as they do not appear to bring in immediate high revenues. There needs to be a balance between what environments have to offer, and what kind of income and employment generation a country wishes to develop. Each beach or scenic area that is being considered for development needs to be studied for its long-term ability to maintain a fresh water supply, to meet sewage requirements, and to sustain adjacent coastal ecosystems. It is generally felt that the average tourist uses twice as much water a day as the average island resident. Oil spills, sewage, and anchor damage from boats have harmful impacts on adjacent beaches, reefs, and seagrass beds. Marine parks and protected areas are examples of tangible efforts to integrate resources and economic opportunities. These parks exist on a spectrum from strict conservation to intense recreation areas, each targeted to different audiences and resource management goals. The Organization of American States (OAS), Division of Regional Development, is presently conducting a study on the potential economic benefits of legally established marine protected areas. While many of these parks exist on paper, most do not have operational budgets, management plans, enforcement capabilities, or educational and recreational facilities. Endangered species legislation also can be a tourism opportunity in terms of developing awareness and preservation of a resource. Tourism projects of any scale and style need to be evaluated in terms of sustainability of the environment, the users, financing options, infrastructure, and management needed to maintain the project. There needs to be an integration of public and private concerns throughout all project phases. It is only through such integration that tourism can continue to be a mechanism to expose and explore the marine resources the Caribbean is so fortunate to have. Country Specifics The following list of Caribbean nations is not 36 comprehensive. Omission of a country does not imply a reduced importance. The following country- specific descriptions are designed only to provide general trends of marine resource needs and opportunities. This presentation focuses on coastal uses, as this is the area most in demand for human settlement needs. Many countries have similar problems based on their common ecologies or development stages. The countries are grouped in an ecological orientation to identify common resource constraints and opportunities. Small islands generally have limited shelf areas and intense pressure on the coastal zone, while larger islands and continental areas have more rivers and other land- use opportunities to diversify economic resources. SMALL ISLANDS Antigua/Barbuda Population/Land Area: 80,000/443 square kilometers. Ecological Features: low flat volcanic island on coral platforms and narrow submarine shelves; white sand beaches, seagrass bays, fringing reefs. Economic Resources: artisanal fishing (conch, lobster); traditional wooden boat building; sand mining to U.S. Virgin Islands; offshore oil leasing. Tourism Elements: economic mainstay, 12 percent GDP, 25 percent labor force; government supports tourism infrastructure (roads, water) and marketing; yacht anchorages, historic and archaeological sites, beaches and reefs. Resource Problems: excessive sand removal destroying reefs; overexploitation of lobster population; resort building on beaches. Recommendations: enforce sand mining laws; establish one ministry for all coastal zone matters. Protected Areas: Diamond Reef, Palaster Reef, Green Island. Barbados Population/Land Area: 240,000/431 square kilometers. Ecological Features: low flat volcanic island on coral platforms, narrow submarine shelves; white sand beaches, mangroves, seagrass bays, fringing reefs. Economic Resources: pelagic, demersal finfish; oil and gas production. Tourism Elements: tourism service sector increased with decline in sugar production, 10 percent GDP, economic mainstay; attractions include beaches, caves, historical sites, and reefs. Resource Problems: nearshore fisheries overexploited; coastal erosion from dredging and construction stressing reefs, changing water circulation patterns and quality; pollution from sewage, wastes, fertilizers. Recommendations: need comprehensive coastal development plan; planning for water treatment and storage requirements. Protected Areas: Barbados Marine Reserve. Research Institutions: Bellairs Research Institute of McGill University; University of West Indies. British Virgin Islands Population/Land Area: 12,000/153 square kilometers. Ecological Features: small clusters of low, hilly volcanic islands; mangroves, seagrasses, salt ponds, coral reefs. Economic Resources: finfish, mangrove nurseries, turtle nesting sites. Tourism Elements: 70 percent GDP, primarily yacht charters and cruise ships; primary basis for island development plans; sailing, beaches, reefs, and historic sites. Resource Problems: mangroves cleared for tourism development causing loss of habitats and increasing sedimentation in seagrass and reef areas; boat anchors damaging reefs; domestic sewage problems. Recommendations: legislation and planning to address mangrove clearing and sewage capabilities. Protected Areas: Wreck of the Rhone Marine Park. Dominica Population/Land Area: 87,000/751 square kilometers. Ecological Features: high rugged volcanic mountains, no coastal plain, numerous rivers and rain forest cover. Economic Resources: hydroelectric power for all needs; artisanal fishing. Tourism Elements: limited due to lack of beaches, potential focus on island's terrestrial natural resources, wildlife and historical features. Resource Problems: hurricane devastation to reefs; maintenance of primary coastal road encouraging shoreline erosion, oil and ship wastes pollution. Recommendations: use inland rock sources for beach and road stabilization; coastal setback policy and tourism planning needed. Grenada Population/Land Area: 1 15,000/344 square kilometers. Ecological Features: numerous steep volcanic islands; mangroves, seagrasses, reefs. Economic Resources: fisheries include nearshore and pelagic finfishes, lobster and conch; turtle nesting and breeding areas. Tourism Elements: one major white sand beach, rainforests, historic sites, and shipwrecks. Resource Problems: overexploitation of all fisheries; beach erosion near tourism centers and airport, coastal tree removal and sand mining increasing erosion; seaborne and solid waste pollution. 37 Recommendations: increase fisheries utilization management; survey sand resources; develop coastal setback policy; have coastal management under one ministry; develop environmental awareness of marine resources. Montserrat Population/Land Area: 12,000/98 square kilometers. Ecological Features: high, rugged, volcanic island, rainforests. Economic Resources: artisanal fisheries for lobster, conch, finfish; steel and traditional wooden shipbuilding industry. Tourism Elements: 77 percent GDP, year-round retirement resort of stayover visitors; tax incentives for tourism projects. Resource Problems: overexploitation of fisheries. Recommendations: improve fisheries management, marketing, and infrastructure. Netherlands Antilles Population/Land Area: 270,000/960 square kilometers. Ecological Features: two island groups — leeward (Curacao, Bonaire, Aruba), low hills and bays with mangroves, seagrasses, fringing reefs; windward (St. Maarten, St. Eustatius, Saba), high, rugged, volcanic with coral reefs and seagrass areas. Economic Resources: oil highest revenue earner for leeward islands; pelagic and nearshore fisheries. Tourism Elements: largest employer; well-educated labor force; natural beauty, pristine reef areas. Resource Problems: marine habitats suffering from industrial and recreational uses; depletion of fisheries off Saba bank; sewage pollution and dumping. Recommendations: enhance public education; regulate fishing access; develop mariculture potential. Protected Areas: underwater parks on Bonaire, Curacao, and Saba. Research Institutions: Foundation Carmabi. St. Kitts/Nevis Population/Land Area: 44,000/204 square kilometers. Ecological Features: high volcanic, narrow coastal shelves. Economic Resources: traditional nearshore fisheries and shipbuilding. Tourism Elements: 1 1 percent GDP, tourism in infancy, growth and marketing encouraged by government, primarily stay-over guests; dive sites, historic attractions, and rain forests. Resource Problems: nearshore fisheries exploited; coastal erosion from sand removal; sewage pollution from tourism activities; inadequate port facilities. Recommendations: develop offshore fisheries, marketing and management structure; investigate mariculture resources; regulate sand mining. St. Maartens. (Courtesy St. Maarten, Saba, St. Eustatius Tourist Office) St. Lucia Population/Land Area: 120,000/616 square kilometers. Ecological Features: high, rugged, volcanic island with extensive seagrasses, coral reefs, few beaches. Economic Resources: pelagic fisheries; seagrasses, coral reefs, few beaches. Economic Resources: pelagic finfisheries. Tourism Elements: third largest commercial activity; attractions are historic and archaeological sites, and wildlife. Resource Problems: erosion from forest clearing and sand mining affecting reef and seagrass habitats; tourism construction stressing habitats. Recommendations: integrate authority of coastal management sectors; use interior sources of rock for construction; increase environmental awareness of tourism impacts and planning. Protected Areas: Maria Islands, Pigeon Islands, Savannes Bay. Research Institutions: Caribbean Environmental Health Institute. St. Vincent/Grenadines Population/Land Area: 101,000/389 square kilometers. Ecological Features: volcanic, mountainous, no seagrasses, reefs, black sand beaches; Grenadines have largest shelf area in Lesser Antilles. Economic Resources: finfishes, lobster, conch; primary sea transport area. Tourism Elements: sailing, beaches, and reefs primarily in the Grenadines. Resource Problems: seaborne tar pollution on beaches; excessive sand mining for construction; waste from yachts. Recommendations: use sand from dune areas; restore tourist beaches. Trinidad/Tobago Population/Land Area: 1.1 million/5,130 square kilometers. Ecological Features: tropical forests, swamps, white sand beaches, reefs. 38 Economic Resources: artisanal fisheries, export trade offish and shells; oil production revenues. Tourism Elements: second major source of foreign exchange, primarily in Tobago; charter boat industry. Resource Problems: pollution pressure and recreation misuse of Caroni Swamp; coastal zone resource use conflicts; overcollecting turtles and shells. Recommendations: develop adequate marketing for fisheries; need comprehensive coastal development plan and authority; enforce collecting laws. Protected Areas: Bucco Reef/Bon Accord Lagoon, St. Giles Island, Saut 'd Eau, Soldado Rock, Kronstadt Island. Research Institutions: Institute of Marine Affairs. LARGE ISLANDS Dominican Republic Population/Land Area: 5.5 million/49,986 square kilometers. Ecological Features: mountainous, extensive mangrove areas. Economic Resources: subsistence fishing, agriculture, and bauxite mining. Tourism Elements: high government priority; increased infrastructure and employment activities. Resource Problems: dependence on fishery imports; new tourism development without environmental assessments; mangrove destruction for fuelwood; ciguatoxic reef fish; overfishing of lobster; illegal collecting of corals, birds, and turtles; sewage from tourism development. Recommendations: develop high priority waste disposal; protect ornamental fishes and birds; increase information on fisheries stocks and critical habitat locations; develop tourism assessment mechanisms. Protected Areas: Silver Banks Humpback Whale Sanctuary, Parque Nacional de Este, Parque Nacional Jaragua, Parque Nacional Montecristi. Research Institutions: Centre de Investigaciones de Biolgia Marina. Haiti Population/Land Area: 6 million/27,700 square kilometers. Ecological Features: western third of Hispaniola Island, low mountains, numerous beaches, bays, mangroves, seagrasses, coral reefs. Economic Resources: minimal marine activities. Tourism Elements: local lack of interest in marine habitats has maintained pristine protected quality; tourism potential growing in recreational marine sector; diving. Stony coral animals require clear, sunlight-filled waters to build the limestone reefs that form large portions of the base of many Caribbean islands. Resource Problems: few inventories of marine resources; pollution near urban centers; mangrove destruction for fuelwood; overexploitation of fish, invertebrate and shell export trade. Recommendations: need assistance and training in fisheries. Jamaica Population/Land Area: 2 million/960 square kilometers. Ecological Features: large mountainous island with coastal plain areas; mangroves and coral reefs. Economic Resources: scientific marine research, subsistence fisheries, bauxite. Tourism Elements: second largest source of foreign exchange; high-density tourist areas of international visitors for culture and marine recreation. Resource Problems: extreme overfishing; domestic and industrial pollution; high sediment loading from bauxite mining; coastal erosion from sand removal; dredge spoils into mangrove areas; unregulated coastal activities including tourism and collecting of reef curios. Recommendations: need comprehensive coastal planning; enforcement of collecting and protected areas legislation; need fisheries development plans; need national permitting agency; increase public awareness of coastal uses. Protected Areas: Montego Bay Marine Park, Ocho Rios Marine Park. Research Institutions: Discovery Bay Marine Laboratory and Port Royal Marine Laboratory of the University of the West Indies. 39 CENTRAL AMERICA Belize Population/Land Area: 154,000/22,962 square kilometers. Ecological Features: 2nd largest barrier reef in the world, extensive flat swampy coast, cays and offshore atolls. Economic Resources: oil and gas, artisanal fisheries; barrier reef resources. Tourism Elements: increasing slowly, diving and boating on offshore islands and reefs. Resource Problems: poaching of turtles, lobster and conch by foreigners; saltwater intrusion into freshwater wells; unregulated coastal activities; seaborne pollution; sewage dumping in mangroves. Recommendations: evaluate freshwater limitations; enforce poaching laws. Protected Areas: Half Moon Cay National Monument; Hoi Chan Marine Reserve. Costa Rica Population/Land Area: 2.6 million/51,022 square kilometers. Ecological Features: rugged mountains, extensive streams and rivers, wide coastal plain, fewer reef and mangrove areas than Pacific coast. Economic Resources: subsistence fisheries; oil. Tourism Elements: undeveloped as coast is remote from urban centers, yet potential due to unspoiled nature of environments. Resource Problems: mangrove clearing for fuel and shrimp ponds; fewer disturbances than Pacific side; some siltation and pollution from pesticides and oil. Recommendations: need information on fishery resources. Protected Areas: Chauita National Park Tortuguero National Park. Research Institutions: Centro de Investigacion en Ciencias del Mar y Limnologia, Universidad de Costa Rica. Guatemala Population/Land Area: 8.4 million/198,779 square kilometers. Ecological Features: coast dominated by beaches, mangroves, estuaries. Economic Resources: artisanal fisheries, lobster export, estuarine mariculture. Tourism Elements: needs development to utilize extensive beach areas. Resource Problems: oil spills; inadequate training in marine resources. Recommendations: improve fisheries marketing infrastructure; inventory marine resources and establish national policy for updating of marine and fisheries legislation. Research Institutions: Centro de Estudios del Mar y Acuacultura, Universidad de San Carlos de Guatemala; Direccion Tecnica de Pesca y Acuicultura. Honduras Population/Land Area: 4.3 million/1 10,074 square kilometers. Ecological Features: mountainous, long coast with wide submarine shelves; mangroves abundant; coral reefs and seagrasses in outlying island areas. Economic Resources: least developed resources in the Caribbean; minerals, commercial fishing exports. Tourism Elements: growing and national priority to develop island recreation areas. Resource Problems: tourism activity without prior environmental assessments; fragmentation of coastal authorities; tourist related sewage; overfishing. Recommendations: increase knowledge and training base for tourism and fishing activities; develop plans to protect island areas; develop local fisheries. Mexico Population/Land Area: 78 million/1.9 million square kilometers. Ecological Features: few mangroves; wide lagoons with undisturbed seagrass and reef areas. Economic Resources: lobster, conch, shrimp fisheries. Tourism Elements: marine recreation and diving rapidly developing with planned centers of Cancun and Cozumel; unspoiled resources. Resource Problems: extent of marine resources needs investigation. Recommendations: encourage balanced tourism development. Protected Areas: La Blanquilla, Cancun-Nizuo-Isla Mujeres, Arrecifes de Cozumel, Isla Contay, Rio Celestrum, Rio Lagartos. Research Institutions: Centro de Investigacion y de Estudios Avanzados del Institute Politeonico Nacional; Centro de Investigacion y Entrenamiento para Control del la Calidad del Agua; Institute de Biologia, Universidad Nacional Autonoma de Mexico; Centro de Ciencias del Mar y Limnolgia; Institute Nacional de Pesca; Universidad Autonoma Metropolitana, Departmento de Zootecnica, Division Ciencias Biologicas y la Salud; Institute Tecnologico y de Estudios Superiores de Monterrey. Nicaragua Population/Land Area: 2.5 million/148,004 square kilometers. Ecological Features: large continental shelf; coastal areas uninhabited due to extensive jungles, rivers and swamps. 40 Economic Resources: shellfish exports, turtle breeding habitats. Tourism Elements: currently no tourism or industry development. Resource Problems: extent of marine resources needs investigation. Recommendations: inventory marine resources. Panama Population/Land Area: 1.8 million/75,548 square kilometers. Ecological Features: mountainous, long coast, wide shelf, sparse mangroves. Economic Resources: world trade port, financial center; shrimp mariculture. Tourism Elements: tourism integrated with service and banking oriented economies; early stages of development with marine resources. Resource Problems: overfishing and collecting of turtles; limited information on coastal resources. Recommendations: develop local fisheries; upgrade technical training; develop coastal resource plans. Research Institutions: Centre de Ciencias del Mar y Limnolgia; Smithsonian Tropical Research Institute. SOUTH AMERICA Colombia Population/Land Area: 27 million/1.1 million square kilometers. Ecological Features: extensive coastal areas influenced by major rivers; island archipelagos offshore. Economic Resources: oil and gas; minerals; minimal local fisheries. Tourism Elements: undeveloped coastal tourism except for island areas, government priority to increase. Resource Problems: tew marine inventories; water and oil pollution; sedimentation; collecting of endangered turtle species; mangrove filling. Recommendations: need data to develop marine resources; implement existing plans; develop underutilized fisheries through increasing information on stock assessment, management and infrastructure. Protected Areas: Parque Nacional Corales del Rosario, Parque Nacional Natural Tayrona, Parque Nacional Natural Isla de Salamanca, Santuario de Fauna Los Flamencos. Research Institutions: Centra de Investigaciones Oceanograficas e Hidrograficas; Facultad de Biologia Marina, Fundacion Universidad de Bogata, Jorge Tadeo Lozano; Facultad de Ingenieria Pesquera, Universidad Technologica de Magdalena; Institute de Investigaciones Marinas de Punta de Betin; Laboratorio del Institute Nacional de los Recursos Naturales Renovables y del Ambiente. Venezuela Population/Land Area: 17.8 million/912,000 square kilometers. Ecological Features: extensive coast that is one- quarter mangroves. Economic Resources: oil industry; commercial fishing. Tourism Elements: increasing international coastal tourism but still only 1 percent GNP; potential development of island and beach areas for recreation and protection. Resource Problems: conflicting demands on coastal areas; destruction of natural habitats; construction causing coastal erosion; filling in of mangrove swamps; overfishing of turtles and lobster; river dams altering hydrologic regimes causing sedimentation of lagoons. Recommendations: increase public awareness of coastal resources; need effective legislation for pollution, endangered species and fisheries regulations; policy for coastal conflicts. Protected Areas: Parque Nacional Archipelago Los Roques, Parque Nacional Mochima, Parque Nacional Morrocoy, Laguna de Tacarigua. Research Institutions: Centra de Investigaciones Biologicas, Universidad de Zulia; Estacion de Investigaciones Marinas de Margarita, Fundacion La Salle de Ciencias Naturales; Instituto Oceanografico; Institute para el Control y la Conservacion de la Cuena del Lago Maracaibo. A. Meriwether Wilson is a tropical marine resources consultant; formerly with the National Oceanic and Atmospheric Administration (NOAA), now with the Organization of American States (OAS) in Washington, D.C. Selected References Goodwin, M., and M. Wilson, eds. 1987. Caribbean Marine Resources: Opportunities for Economic Development and Management. Washington, D.C.: United States Agency for International Development, and the United States National Oceanic and Atmospheric Administration Agency. Jackson, I. 1986. Carrying capacity for tourism in small tropical Caribbean islands. Industry and Environment, 9(1) United Nations Environment Programme. Ogden, )., and E. Gladfelter, eds. 1983. Coral Reefs, Seagrass Beds, and Mangroves: Their Interaction in the Coastal Zones of the Caribbean. Montevideo, Uruguay: UNESCO Reports in Marine Science Number 23. Putney, A. 1982. Survey of conservation priorities in the Lesser Antilles — Final Report. Caribbean Environment Technical Report No. 1. St. Croix, U.S. Virgin Islands: Caribbean Conservation Association. Van'T Hoff, T. 1985. The economic benefits of marine parks and protected areas in the Caribbean region. In, Proceedings of the Fifth International Coral Reef Congress, Tahiti, 27 May-1 lune, 1985, pp. 551-556. 41 Geology of the Caribbean -New techniques, including broad-range swath imaging of the seafloor that produces photograph-like images, and sat- ellite measurement of crustal movements, along with plans for new scientific drilling, have excited geologists, and prom- ise to explain the complex geology of the region. 90 75' 42 by William P. Dillon, N. Terence Edgar, Kathryn M. Scanlon, and Kim D. Klitgord I he Caribbean Sea (Figure 1) often seems to be a distinctive place — geographically and culturally. Whether that is true or not, the Caribbean, most certainly, is a distinctive place geologically. The geological Caribbean is a separate plate of the Earth's surface, moving semi-independently of the other plates that surround it. This movement causes the plate to grind against the surrounding plates, and thus, its boundaries are disclosed by a band of earthquakes that extends around the plate's Figure 7. Geography and bathyn etry of the Caribbean region U 0-200 m D 200-2000 D 2000-5000 n >sooo 10' 43 STRONG MODERATE WEAK N. AMERICAN PLATE CARIBBEAN PLATE . AMERICAN PLATE PLATED figure 2. Relative earthquake activity of the Caribbean. The Caribbean is a separate plate of the Earth's outer shell, and its boundary is defined by a band of earthquakes that are caused by the grinding of one plate against another, and the stresses within the plate boundary zones caused by plate movements. periphery (Figure 2). Some places that usually are considered part of the Caribbean — the Bahamas, Cuba, and Mexico's Yucatan Peninsula — lie outside the band of earthquakes (therefore, off the plate), and so are not part of the geological Caribbean. Of the three main basins of the Caribbean region, the Yucatan, Venezuelan, and Colombian basins, only the latter two are included in the Caribbean Plate. Presently, the Caribbean Plate — flanked by the North American and South American plates- moves eastward, or possibly slightly north of eastward. As the Caribbean Plate moves, the American plates are driven under it on its eastern side, a process known as subduction. Along the east- west trending northern and southern boundaries, the Caribbean Plate is sliding past the American plates— an extreme oversimplification, which we will consider more extensively. Finally, on the west, the Cocos Plate is being driven northeastward, and is being subducted beneath the Caribbean. Since the boundaries of the plate are where the activity is, we will look at each one. The Boundaries of the Caribbean Plate The Northern Boundary. The northern boundary of the Caribbean Plate is aligned east-west, essentially parallel with the direction of movement of the plate. The basic movement of the faults at the boundary is strike-slip, that is, the movement on the faults (slip) is parallel to the trend of the faults (strike). Thus, a very simple fault system could exist if the plate boundary were straight, but it is not. The northern plate boundary has two major deflections (Figure 3). Moving west along the boundary, there is a northward bend at the island of Hispaniola (the Dominican Republic/Haiti), and a southward jog between Jamaica and the Yucatan Peninsula. Because the Caribbean Plate is moving relatively eastward, the Hispaniola bend creates a protuberance that is being crushed against the North American Plate. The result is the formation of folds and thrust faults that grow continuously over time as the plates move, such as those shown in one of our recent profiles (Figure 4). These are found both offshore and on land in Hispaniola. The abrupt jog in the plate boundary between Jamaica and Yucatan creates an ever-widening gap, or spreading center, as the Caribbean Plate moves relatively eastward. As the spreading center has opened, the potential gap has been filled by molten material that has welled up from below the rigid outer shell of the Earth. The process is similar to that occurring at normal ocean-opening spreading centers, like the Mid-Atlantic Ridge, and the new crust that is formed is essentially the same as normal oceanic crust. The result of the opening, then, is the formation of the Cayman Trough, the floor of which is a narrow band of new ocean crust that is being formed along the northwestern edge of the Caribbean Plate. This probably is the smallest actively developing ocean basin in the world. 44 Stresses along the northern plate boundary have caused uplift in many of the islands, and subsidence in some other areas. This has resulted in exposure on land of marine limestones, reefs, and marine terraces in many areas. Upraised limestone strata (layers) on a fault block create the spectacular cliffs of Mona Island, between Puerto Rico and Hispaniola (Figure 5). Upraised limestone strata on Puerto Rico's north coast have been weathered and eroded into steep pits and peaks, known as karst topography. Figure 6 shows karst near Arecibo, where a karst sinkhole has been adapted to make it a reflector for one of the world's largest radio telescopes. The Southern Boundary. The motion at the straight, eastern part of the southern plate boundary is dominantly strike-slip (refer back to Figure 3). The western part of the boundary forms a great curve from western Venezuela to western Colombia. This shape, in conjunction with the movement of the Caribbean Plate and the plate collision and subduction that extends along the entire west coast of South America, creates compression that causes major faults and uplifts here, at the northern end of the Andes. Some subduction of the Caribbean may be occurring north of Colombia, according to some researchers. Motion between the North and South American plates appears to be slow, but what there is seems to put the Caribbean Plate into a vise, slowly crushing it in a north-south direction. This has resulted in folding of sediments south of Puerto Rico and Hispaniola, and north of western Venezuela and Colombia. The Eastern Boundary. The eastern boundary ot the Caribbean Plate is a subduction zone, in which the American plates are driven under the Caribbean (refer again to Figure 3). An idealized cross-section of this boundary, extending east-west through Barbados (Figure 7), shows that the Caribbean Plate, moving relatively eastward, is scraping off the sediments that lie on the South American Plate and is forming an accretionary sediment pile. The sediments have been derived mostly from the erosion of South America. New sediments on the seafloor arrive at the convergence on the westward-moving basement conveyor belt (the South American Plate). These sediments initially are shoved under the pile, and eventually are crumpled and faulted up into a thick ridge of sediment where the plates converge. In one place, this ridge of deformed sediment extends above the sea surface to form the island of Barbados. Thus, Barbados is formed of folded sediments with a cap of reef limestone (Figure 8), unlike all of the other Lesser Antilles, which are volcanic. Where the American plates bend over and start to descend, earthquakes occur (refer again to Figure 2). The earthquakes are as shallow as 10 to 20 kilometers near the bend, and extend in a dipping band to more than 150 kilometers beneath the Lesser Antilles island arc. The crust of the descending Atlantic plates begins to melt as it descends into the hot rocks of the mantle. The molten material, or magma, thus created rises to form volcanoes that become the Lesser Antilles island arc. The spectacular pitons (twin peaks) on St. Lucia (Figure 9) have formed from volcanic vents that were filled with magma that solidified, then had the surrounding rocks eroded away. Nearby, on southern St. Lucia, the boiling water springs of Soufrieres give evidence that these volcanoes still are active. The volcanoes of the Lesser Antilles are famous for their large, explosive eruptions, such as ZONE OF FOLDING AND THRUST FAULTING CARIBBEAN PLATE BOUNDARY ZONE OF NEW OCEANIC CRUST APPROXIMATE DIRECTION OF CARIBBEAN PLATE MOTION RELATIVE TO N and S AMERICA Figure 3. Geological features of the active boundary zone of the Caribbean Plate. (Figure adapted from Case, I. E., and T. L. Holcombe, 1980) 45 0-N 0 20 40 KM CO 2- Q- ? J uj Q 4- PROFILE 18 -9 CO 11 Q •2. O o LU CO -4 SEA FLOOR FOLDED SEDIMENTS 0 < -6 -8 Figure 4. A seismic profile recently collected by the U.S. Geological Survey north of Haiti off the island of Hispaniola. Here, at a compressional zone created by an irregularity in the plate boundary, sediments north of the Caribbean hate are crumpled. The folds continually grow, and new folds are created as a result of the continuous movement of one plate relative to the other. the 1902 eruption of Mt. Pelee on Martinique. In the first three quarters of this century, they killed nearly 30,000 people — more than those killed during that period by all other volcanoes in the world. The present arrangement of volcanoes is quite recent, geologically. Prior to about 5 million years ago, the island arc was straighter, and the arc included the islands of St. Barthelemy, Antigua, and the eastern part of Guadeloupe, as well as the islands to the south. The western part of Guadeloupe and the active volcanic islands to the northwest are younger. An even older island arc, probably inactive for more than 15 million years, is represented by the submerged Aves Ridge. At the northern end of the subduction zone, as the plate boundary swings around to the west toward Puerto Rico and Hispaniola, diagonal subduction continues to drive the North American Plate beneath the Caribbean Plate. Because little sediment is available here to form an accretionary sediment pile, a great deep is formed instead. This is the Puerto Rico Trench, and with depths greater than 8,200 meters, it is the deepest area in the Atlantic Ocean. The Western Boundary. The western boundary of the Caribbean Plate, where the Cocos Plate is being thrust beneath the Caribbean, is a subduction zone similar to that along the eastern boundary. The trench formed by the plate boundary here, however, is not filled by a ridge of deformed sediment scraped from the downgoing plate, as it is at the eastern boundary. Sediments on the Cocos Plate are thin, and there is little sediment input from Central America, and therefore the 6-kilometer-deep trench remains unfilled, as in the Puerto Rico Trench. The northern part of Central America (parts of Guatemala, Belize, and Honduras) is formed of a block of very old (more than 300-million-year-old) continental crust that has been deformed and faulted more recently. The remainder of the land along the western plate boundary consists of volcanic rocks and bands of folded sediment — all related to the subduction process. Origin of the Caribbean Crust Most of the Caribbean area — the Venezuelan, Colombian, and Yucatan basins — is floored by crust that apparently is oceanic rather than continental in origin. Oceanic crust is formed at a spreading ridge from molten material that wells up from the interior of the Earth as two plates move apart. As determined by acoustic studies, oceanic crust worldwide is remarkably uniform in thickness and structure, and it is much thinner than continental crust (7 to 10 kilometers versus 30 to 40 kilometers thick). It is characterized by a "spreading" topography, or lineations that originated as a result of its formation, and, commonly, by a clearly identifiable striped pattern of magnetic anomalies. Remarkably, none of the above characteristics apply to much of the crust in the Venezuelan Basin and part of the Colombian Basin, which is thicker and smoother than normal oceanic crust, and has a very poorly defined magnetic anomaly pattern. The differences have attracted a bevy of imaginative hypotheses to explain why the seafloor here is different — among them the idea that widespread eruptions occurred about 80 million years ago, creating molten flows of volcanic rock that covered the original topography and left an atypically smooth surface. The cover of volcanic rock also may be responsible for subduing the magnetic anomaly field. Numerous hypotheses on the origin of the Caribbean have been proposed, but with the acceptance of plate tectonics, two have dominated the current thinking. One assumes that a branch of the Atlantic crustal spreading system extended through the Caribbean region to the Pacific Ocean, and that new oceanic crust was created between the North and South American plates as the two 46 Figure 5. Cliffs, 60 meters above sea level, at Mona Island between Puerto Rico and the Dominican Republic. Mona Island is a fault block on the northern side of the Caribbean. The marine limestones that form the island have been shoved up above sea level in response to stresses at the plate boundary. (Photo by W. Dillon, USCS) separated during their westward migration (see box, page 49). The other proposes that the crust formed in the Pacific Ocean, and that it was wedged between the North and South American plates as they separated. Smooth crustal surfaces and weak magnetic anomaly patterns do characterize the crust in parts of the western Pacific Ocean, lending support to a Pacific-origin. Of the two hypotheses, the latter has had the most adherents in recent years. However, new ideas on ocean-opening in place, the first possibility (above), seem to simplify many Caribbean geological problems, and are gaining credence. Search for Marine Geologic Resources The need for economic development in the Caribbean caused the U.S. State Department to recently ask the oceanographic community to hold two workshops. These have resulted in reports that include major sections on the development of marine geologic resources in the region. The first report was the outgrowth of a request to the National Research Council, Ocean Studies Board, which called a meeting in January 1986 of U.S. scientists interested in Caribbean problems. This request attracted more than 1 15 written responses and proposals, and a report was prepared by David A. Ross (Woods Hole Oceanographic Institution) and Harris Stewart (an independent consultant). The second report, which stemmed from a State Department, Agency for International Development (USAID), request to the National Oceanographic and Atmospheric Administration, resulted in a workshop held in September 1986, which was attended by scientists from the United States and many Caribbean countries. This is discussed by A. Meriwether Wilson in this issue of Oceanus (page 33). The meetings considered a broad variety of topics, but the conclusions and recommendations for geological work were quite similar. 47 Figure 6. Irregular topography in uplifted marine limestones on the northern coastal plain of Puerto Rico at Arecibo. The pits and steep round-topped peaks are created by solution of the limestone along cracks by rainwater and groundwater, creating a topography known as karst. One of the pits shown here has been used to create the dish reflector for one of the world's largest radio telescopes. Note the four-story building in the foreground for scale. (Photo by W. Dillon, USGS) Aside from petroleum, which will be developed by industry, the most important marine geologic resources in the Caribbean probably will be sedimentary, and therefore an understanding of the sedimentary processes, present and past, is imperative. Perhaps the most valuable nonpetroleum geological resource of the marine realm is sand and gravel, needed for construction and beach replenishment. Onshore deposits of these materials commonly are inadequate and, in the Caribbean, the mining of beaches for these resources has begun. Such activity can be very unwise — because it can aggravate shore erosion, and can destroy features attractive to tourists, an important source of income in many Caribbean countries. Studies, such as those done by the U.S. Geological Survey in Puerto Rico, where the problem of illegal mining of beaches is severe, show that mining of offshore sand and gravel can be done safely, if we understand how underwater streams of sediment move. In some places, such flows of sediment are lost from the shelves to the deep sea. These areas are ideal for mining. In other locations, flows of sand on the island shelves appear to nourish the beaches, so these flows should not be disturbed. Knowledge of the locations of sand and gravel deposits, and the dynamics of underwater sediment migration, are the key to safe and effective use of these resources. The knowledge needed to use offshore sand and gravel resources is essentially identical to that needed to locate and extract other sedimentary mineral deposits in the offshore region, known as placer deposits. These accumulations of dense minerals have been concentrated by the action of waves or currents. The deposits of greatest interest are those with economically valuable minerals such as gold, platinum, and minerals containing titanium, chromium, and rare earths. Both reports to the State Department agree that studies needed to understand the sedimentary deposits and safe extraction of resources include side-scan sonar and seismic-profiling surveys, extensive core sampling, current measurements, and biological surveys. The geological surveys need to be done on at least two scales. On the regional scale, side-scan sonar and other broad geophysical surveys of the entire continental or insular margins of a country should be carried out, as the U.S. Geological Survey has done around Puerto Rico and the U.S. Virgin Islands. This allows general mapping to identity potential resource sites and understand broad geologic problems. On the local scale, high- resolution surveys can identify economic deposits, and give the details of sedimentary processes. The search for offshore oil and gas resources in the Caribbean has been affected recently by economic conditions that have slowed the petroleum industry worldwide, but the sites of future resources probably will follow the pattern of the past when exploration resumes. Most petroleum resources have been found in the southern continued on page 50 48 The Opening of The Caribbean H, [cnv (he Caribbean ocean basin formed remains the subject of great deal of speculation. One explanation is given by the adjoining diagrams, which represent several stages in a recent conceptual model of how the Caribbean and North Atlantic formed. Diagram A shows the North Atlantic and future Caribbean as it is thought to have appeared 150 million years ago, 25 million years after North America and Africa started to drift apart. Very little of the Caribbean crust had formed at this time, but South America and Central America were about to break apart. The broad, open arrows indicate directions of plate drift relative to North America, which for the purpose of illustration, is imagined as remaining fixed. Diagram B shows locations of the continents 1 78 million years ago. At this time, 32 million years of drift had resulted in formation o\ part of the Caribbean crust. Diagram C shows the Caribbean at the end of its opening phase, 80 million years ago. At that time the active spreading center died, and floods of molten volcanic rock flowed across the seafloor of most of the Caribbean Basin. Diagram D shows that, by 36 million years ago, a reorganization of plate boundaries had occurred. The northern boundary of the plate had become a strike-slip plate margin that cut off the Yucatan Basin as it does now, but at that time the northern boundary was located south, rather than north of Hispaniola and Puerto Rico. A subduction zone, which eventually became the Aves Ridge, was the beginning of subduction in the eastern Caribbean. In Diagram E, we show that, at 10 million years ago, the northern boundary of the Caribbean was approximating its present configuration. It had jumped northward, so that Hispaniola and Puerto Rico were now on the Caribbean Plate, and they were drifting relatively eastward— as they do today. Furthermore, a jog in the plate boundary west of Hispaniola had begun to create the present Cayman Trough. The subduction on the eastern plate boundary had jumped eastward to its present position at the Lesser Antilles island arc. On the west, northern Central America had drifted to a location south of Yucatan from its previous location, south of central Mexico (note its location on the three diagrams on the left). Also on the west, the present subduction zone pattern had developed. The present situation is, of course, as shown in Figure 3 (page 42). This summary of Caribbean development continued on page 50 A 150MYBP 49 Continued from page 49 is taken from a 12-step model created by Kim Klitgord of the U.S. Geological Survey and Hans Schouten of Woods Hole Oceanographic Institution (Klitgord, K. D., and H. Schouten, 1986, Plate kinematics of the central Atlantic, In Vogt, P. R., and B. E. Jucholke, eds., The Geology of North America, Vol. M, The Western North Atlantic Region, Geological Society of America, pp. 351-378). Although this is one of the most recent models of Caribbean development, it must be considered as one of a series of competing hypotheses, some of which are very different. Caribbean — Colombia, Venezuela, and Trinidad and Tobago. These resources occur in the thick folded and faulted sediments of northern South America. Petroleum exploration in Central America has been disappointing, and generally, little oil has been found in the Caribbean islands. In the Greater Antilles, oil exists in Cuba and one former field in the Dominican Republic. Barbados, the sedimentary island in the accretionary sediment pile of the eastern Caribbean, does have oil and gas production. This may bode well for future exploration in the folded sediments of the eastern Caribbean. The rest of the Lesser Antilles, being volcanic islands, probably have little potential for petroleum. New Directions in Research Because of the wide variety of geologic activities in the Caribbean area, such as earthquakes, volcanism, and various other plate boundary interactions, there has been a continuing interest in the area by scientists from the Western Hemisphere, and from Europe. Two exciting newer approaches currently being applied in the Caribbean are techniques for broad-range swath imaging of the seafloor, and the direct measurement of the movement between plates. New proposals for drilling in the region are also generating interest among scientists. Swath imaging is of two types: multibeam bathymetry systems that generate swath contour maps of the bottom, and side-scan sonar systems that generate swath images of the seafloor that look like aerial photographs taken over land. Side-scan sonar actually is very much like photography, because it provides information on the shape as well as the reflectivity of objects it images; of course it uses sound rather than light to create the image. Such a photograph-like image is exciting to marine geologists, who until recently had to satisfy themselves with two-dimensional, cross-sectional profiles. The broadest range swath device (as much as a 60-kilometer swath) is the GLORIA side-scan-sonar system; its towed sending and receiving unit, or "fish," is shown in Figure 10. GLORIA (Geologic Long Range Inclined Asdic) surveys in the Caribbean Sea have been carried out by the system's builders, the British Institute of Oceanographic Sciences (IOS) on the eastern Caribbean Plate boundary region, and 10MYBP E KEY FUTURE SPREADING CENTER RIFT ZONE ACTIVE SPREADING CENTER ABANDONED SPREADING CENTER SUBOUCTON ZONE CONTINENTAL EDGE PRESENT DAY 200m ISOBATH MYBP MILLION YEARS BEFORE PRESENT by the U.S. Geological Survey, in cooperation with IOS, on the northern plate boundary around Puerto Rico and in the Cayman Trough. The survey in the folded sediments of the eastern plate boundary region disclosed previously unknown, volcano-like features from which pressurized mud (possibly charged with gas) had erupted on the seafloor. The Puerto Rico and Cayman Trough GLORIA surveys provided continuous coverage across the northern plate boundary. At Puerto Rico, we can now, for the first time, identify where the strike-slip motion between plates occurs. The Puerto Rico survey also disclosed linear patterns of submarine canyons north of the island, formed by sediment derived from rivers and shore erosion that spilled off the edge of the shelf durmg storms and flowed down the slope (Figure 1 1 ). Figure 1 1 also shows a huge amphitheatre, created by the slumping away of 4,000 cubic kilometers of rock. Such a slump can generate a large and destructive seismic sea wave (tsunami), so the likelihood of such events is a matter for concern. At the Cayman Trough spreading center, GLORIA was used to locate the actively spreading ridge, and to reveal the sea-floor volcanoes that complicate the floor of the trough. In the Cayman Trough, and in the deep basin within the Virgin Islands, GLORIA images have been interpreted along with data from a swath-bathymetry device (measures water depth). The photograph-like quality of GLORIA and the precise bathymetric maps created by swath-bathymetry devices, such as Sea Beam, are mutually supportive for purposes of data interpretation, so the combination is especially valuable. French scientists have been very active in collecting Sea Beam data in the Caribbean. The relative motion across the northern plate boundary of the Caribbean, which has been deduced indirectly, soon will be measured by precise location of ground stations over several 50 WEST EAST AVES RIDGE EXTINCT ISLAND ARC ST VINCENT ACTIVE ISLAND ARC BARBADOS 400 500 600 700 KILOMETERS Figure 7. The eastern margin of the Caribbean plate at the location of Barbados and St. Vincent. (Figure adapted from Westbrook, C. K., and W. R. McCann, 1986. Subduction of Atlantic lithosphere beneath the Caribbean, In Vogt, P. R., and B. E. Tucholke, eds., The Western North Atlantic Region, The Geology of North America, Vol. M, pp. 341-350. Boulder, CO: The Geological Society of America) years, using Earth-orbiting satellites. Presently, this direct measurement technique is being used between Hispaniola and the Bahamas by Carl O. Bowin, a Senior Scientist at the Woods Hole Oceanographic Institution. Plans for other similar measurements are being made. Many of the geological mysteries of the Caribbean, such as the problem of whether the crust drifted in from the Pacific or formed in place, can best be solved by actually sampling the sediments and basement of the deep basins. Two scientific drilling cruises were carried out by the National Science Foundation's (NSF's) Deep-Sea Drilling Project ship C/omar Challenger in 1969 and 1972. This drilling, at 1 1 sites, sampled the rock beneath the sediments of the Caribbean, and showed that molten flows of volcanic rock had covered the sea floor about 80 million years ago. This volcanic episode may have caused the basement rock of the Caribbean to be different from normal oceanic crust, as discussed previously. Age of these volcanic flows was determined by paleontologic dating of microfossils obtained in the drilled cores. Dates of gaps in sedimentation in the cores — gaps produced by deep-sea erosion — also helped to determine when the volcanic barrier of Panama was erected, which cut off the Caribbean from the Pacific. After a 15-year hiatus, a large group of scientists have recently met, in mid-November in Jamaica, to plan a new drilling cruise. The NSF's new Ocean Drilling Project vessel IOIDES Resolution will be used, perhaps by 1991. With our present greater understanding of the Caribbean region and the deeper drilling capability of the IOIDES Resolution, we should be able to bring this new sampling to bear on a fascinating set of geological problems — such as the evolution of plates and basins, the development of convergent accretionary margins, and the pattern of changing environments over geologic time caused by the rearrangements of drifting plates. One of the prime targets will be an area of the southeastern Venezuelan Basin, which seismic profiles show was not covered by the floods of molten volcanic rock that covered the rest of the Colombian and . , . Figure 8. Barbados — a view of part of the contorted sediment pile that forms the island. The sediments are scraped off the South Atlantic Plate and crumpled as that plate is thrust under the Caribbean Plate. (Photo by K. Scanlon, USGS) Figure 9. Les Pitons of St. Lucia in the Lesser Antilles probably are the remains of volcanic vents that were filled with molten magma that solidified. The surrounding volcanic rocks were eroded away. These spines are about 800 meters high. (Photo courtesy of the St. Lucia Tourist Board, through Hill and Know/ton Inc., New York) 51 KILOMETERS 50 Figure 10. Jesting the GLORIA launching system in San luan harbor, Puerto Rico. The GLORIA "fish" is the torpedo-like object held in the gantry cradle that rotates and slides out across the ship's stem to allow a safe launching. The fish, towed 300 meters behind the ship, carries the devices that send sound pulses out to the side of the ship's track and receive the returning echoes, thus allowing an image of a broad swath of seafloor to be created as the ship steams along. (Photo by Dann Blackwood, USGS) Venezuelan basins. The age of the basement rocks and latitude at which they were formed (which can be determined from their magnetic characteristics) will be important information in judging competing hypotheses of Caribbean formation. The brief listing of research topics here only scratches the surface of present geological research in the Caribbean. Geologists have been fascinated and mystified by the Caribbean for generations, and, although we now understand the region far better than our grandfathers, there are still major questions unanswered in this region of very complex geology. William P. Dillon, N. Terence Edgar, Kathryn M. Scan/on, and Kim D. Klitgord are research geologists with the U.S. Geological Survey. Dillon, Scan/on, and Klitgord are based in Woods Hole, Massachusetts, and Edgar is at the USGS National Center in Reston, Virginia. Acknowledgments We thank our graphics department, Patty Forrestel, Dann Blackwood, and Jeff Zwinakis for their interest and help. Thanks also are due to Peggy Mons-Wengler, who prepared the manuscript. Figure / / . A small portion of the GLORIA side-scan sonar image of the region around Puerto Rico. This is a mosaic of four east-west side-scan tracks that shows the straight submarine canyons on the northern slope of Puerto Rico. A large amphitheater apparently was created by slumping that could have been triggered by earthquakes in this area of high earthquake frequency. If this large area of rock and sediment slid as a single mass, large and destructive sea-surface waves (tsunamis) would have been generated. Part of a second, smaller amphitheater is visible at the right edge of the image. Selected References Bonini, W. E., R. B. Margraves, and R. Spagam, eds. 1984. The Caribbean — South American Plate Boundary and Regional Tectonics. Memoir 162, 421 pp. Boulder, CO:The Geological Society of America. Bowin, C. 1976. Caribbean gravity field and plate tectonics. Geological Society of America Special Paper No. 169. 79 pp. Case, ]. E., and T. L Holcombe. 1980. Geologic-Tectonic Map of the Caribbean Region, U.S. Geological Survey, Miscellaneous Investigations Series Map, 1-1 100, 3 sheets. Dengo, G., and ). E. Case, eds. The Caribbean Region, The Geology of North America Vol. H. Boulder, CO: The Geological Society of America. In press. EEZ-SCAN 85 Scientific Staff. 1987. Atlas of the U.S. Exclusive Economic Zone, Eastern Caribbean. U.S. Geological Survey Miscellaneous Investigations, 1-1864-B. 58 pp. Scale 1:500,000. Nairn, A. E. M., and F. G. Stehli, eds. 1 975. The Gulf of Mexico and the Caribbean, The Ocean Basins and Margins, Vol. 3. 706 pp. New York: Plenum Press. 52 Changing Climate and Caribbean Coastlines by Frank Gable I ourism is a major source of income in the Caribbean. This fact, coupled with a rapidly increasing population and its accompanying demand for space and resources, means that any rise in relative sea level will have severe repercussions. Such a rise has been documented, and it appears likely that it will continue for the foreseeable future. The Caribbean is particularly vulnerable to a projected increase in sea level because it is made up largely of island nations that have far more coastal zone per unit of land area than do continental nations. Furthermore, many government and international funding agencies have made, and continue to make, important economic and environmental decisions without considering the possibility of a rising sea level. Causes for the Sea-Level Rise Rise in sea level has been substantiated by recent data, and by reinterpreting older data, and is due to several causes: Atmospheric Warming. Since 1880, the global atmosphere has warmed by 0.6 degrees Celsius (1 degree Fahrenheit). This warming trend is at least partially because of the measured increase of carbon dioxide and trace gases in the atmosphere — the so- called "greenhouse effect" (See Oceanus, Vol. 29, No. 4, pp. 2-8). Although the Earth was about as warm in the 1930s and '40s as it is today, the earlier warming was confined mostly to the higher latitudes of the Northern Hemisphere. Recent warming is more dispersed globally, and thus is likely to have more effect on the Caribbean. This warming trend acts in two ways to increase sea level: First, it causes an increase in ocean volume through thermal expansion; and second, it causes the melting of land- bound ice. In October 1985, a conference was held at Villach, Austria, on atmospheric gases and climatic change. This conference, sponsored by the United Nations Environment Programme (UNEP), the World Meteorological Organization (WMO), and the International Council of Scientific Unions (ICSU), arrived at the conclusion that a projected global warming of 1 .5 to 4.5 degrees Celsius (2.7 to 8.0 degrees Fahrenheit) during the next century would lead to a sea-level rise of from 20 to 140 centimeters (0.65 to 4.60 feet). Other estimates for the projected rise in sea level vary: The United States National Academy of Sciences (NAS) forecasts a 70-centimeter (2!/3 foot) global rise in the next century, with a rise of 28 centimeters by the year 2025. The United States Environmental Protection Agency (EPA), sees a global rise of 137 centimeters (41/? feet) during the next 100 years, with a rise of 38 centimeters (1 14 feet) by the year 2025. The consensus is that global sea levels will rise from 61 to 183 centimeters (2 to 6 feet) during the next century, with a rise of 30 centimeters (1 foot) during the next 40 years. However, for part of the Caribbean region, the rise during the next 40 years is expected to be 15 to 20 centimeters greater than the average global rise, because of a simultaneous subsidence of the land. Natural Subsidence. The Caribbean region is very active, geologically. It is on a separate tectonic plate, caught, as if in a vise, between the North American and South American plates (see page 42). Consequently, it is subject to frequent earthquakes and volcanic activity. The coastlines of the region contain topographic evidence of changes in land level, both up and down, with no discernible trend in either direction. This fact, coupled with the paucity of long-term tide-gauge data (as opposed to Europe, where some tide gauges have been in operation since the 19th Century), makes planning for the region even more difficult. But, there are other natural factors, such as the compaction of fine- grained deposits due to the weight of overlying sediments, and the oxidation of highly organic soils — such as peat — which contribute to subsidence. Man-Made Subsidence. Human intervention can induce subsidence or accelerate naturally occurring subsidence. Examples of these activities that have been seen in the Caribbean are the pumping of ground water for agriculture, municipalities, or industry; and the extraction of crude oil and natural gas (a subsidence of 3.4 meters — 1 1 feet — was measured in Venezuela's Lagumillas oil field in the period 1926 to 1954). Also, there is compaction of sediments caused by 53 vibration, and by buildings and other engineering works. Other major causes of subsidence in the islands are the mining of sand and gravel, and land reclamation and drainage projects. A Wild Card. Hurricane formation requires sea-surface water temperatures of 27 degrees Celsius (81 degrees Fahrenheit) or higher. The Caribbean Sea is about 25 to 26 degrees Celsius (77 to 79 degrees Fahrenheit) in winter, and 28 to 29 degrees Celsius (82 to 84 degrees Fahrenheit) in summer; thus, a global warming trend may well cause an extension of the hurricane season. It also may lead to hurricanes forming at higher latitudes within the Caribbean region. In general, an increased frequency of severe storms will tend to flatten the typical beach profile and cause increased shoreline destruction in the area. Record storm surges of greater than 7 meters (23 feet), with associated winds of 200 kilometers per hour (124 miles per hour), have been recorded within the last 20 years. In 1961, hurricane Hattie produced a storm surge of 4 meters (13 feet) on the coast of Belize, with significant island flooding and erosion. Impacts Preliminary estimates of tide-gauge trends in the Caribbean region suggest that, in recent years, relative sea level has risen at the rate of 32 millimeters (Va inch) a year. The "Bruun Rule," first promulgated by Per Bruun in 1962 in the journal of the Waterways and Harbors Division, and considered to be a benchmark in the field, states that a 1 centimeter (0.39 inch) rise in sea level will generally result in a 1 meter (39.37 inches) shoreline retreat. Beach resorts provide important revenues to coastal areas throughout the Caribbean, and relatively few of the most intensively developed resorts have beaches broader than about 30 meters (98 feet) at high tide. The projected rise in relative sea level of 30 centimeters (12 inches) during the next 40 years will inundate up to 20 to 50 meters (66 to 164 feet) of beach, which, in many cases, will be the entire beach. The major tourism area on Grenada is Grand Anse; most of the hotels are situated on or near this 2-kilometer-long beach, which has eroded at the rate of 70 centimeters (2!/3 feet) per year between 1 970 and 1 982. The causes of this erosion are mining of offshore sand, and possible relative sea-level rise. Another place where the mining of sand and aggregate is creating serious problems is Vigie Beach, on the island of St. Lucia. A typical crescent-shaped pocket beach, it is about 1.5 kilometers (5,000 feet) long and 20 to 30 meters (66 to 98 feet) wide. Because of its proximity to the St. Lucia capital of Castries, it has served as the primary source of sand and aggregate for building in that city. In an analysis of Vigie Beach, using aerial photographs taken from 1940 to 1970, regression of the beach averaged 60 centimeters (2 feet) per year. An estimated US$10 million of real estate was at risk by 1970. By 1973, the beach front of the Red Lion Hotel at the southern end of the beach had eroded to just pebbles and cobble stones, resulting in a reduction of tourism and lost revenues. Mining of bottom sand, and most dredging, generally eliminates a natural breakwater that acts to reduce wave energy falling on a shoreline. Modification of tidal inlets also can have an effect on the erosional and depositional pattern of abutting beaches. With projected sea-level rise, and the prospect of even more tropical swells from storms, this should be of great concern. The countries of Dominica, Grenada, Jamaica, St. Christopher and Nevis, St. Lucia, and St. Vincent appear to be in the most jeopardy from these hazards because of their sand-mining activities. Over time, a 1- to 2-meter rise in sea level will be likely to inundate wetlands, accelerate erosion, and exacerbate coastal flooding — threatening coastal structures and increasing the landward penetration of saline waters in estuaries and freshwater aquifers. Wetlands, consisting for the most part of mangrove swamps, along undeveloped coastlines are expected to migrate readily into adjacent lowlands. Yet, because most coastal lowlands have steeper gradients, the net result will be a reduction in these natural storm barriers, and a reduction in their role in erosion control. Coral reefs — prominent formations in the Caribbean — also are endangered by a rise in relative sea level. These reefs provide a barrier for the shores behind them. Other potential problem spots are urban areas located in low-lying coastal areas, such as Belize City, Belize, where about 28 percent of that country's population of 150,000 live. Today, it is only 15 centimeters (6 inches) above sea level, with a tendency toward destruction from the hurricanes which impact there, dead-center, on an average of once every 30 years. Another example is Georgetown, Guyana's capital and largest city, with a population of about 200,000. It is located on the coast, and built on drained marshland protected by dikes. Fully 90 percent of Guyana's total population of almost 800,000 live on the narrow coastal plain, often on land reclaimed from tidal marshes and mangrove swamps. Paramaribo, Suriname's main port and capital, with a population of 182,000, has many wooden buildings built on stilts to protect them from tidal action. Also, Cayenne, the capital and main port of French Guiana, with a population of 38,000, is situated on a low-lying island in the Cayenne River estuary. Responses How have the nations of the Caribbean responded to existing or potential natural hazards (including a possibly accelerated rise in relative sea levels) along their coastal zones? One example is Costa Rica, where permits from the Tourism Institute and the Ministry of Public Works and Housing must be secured in order to develop within 200 meters (656 feet) from mean sea level along 75 percent of that country's shoreline. Another example of special policies for land-use planning within a shore area is in Guatemala. Although not as refined a policy as in Costa Rica, the coastal area of Guatemala has been 54 treated as a separate situation with regard to zoning. The coastal area stretches inland 3 kilometers (1.86 miles) from the shore. Barbados, since April of 1984, has maintained a coastal conservation project unit, whose tasks include the monitoring of natural phenomena such as hurricanes, winter swells, and sea-level rise. Further, there is now a building setback requirement of 30 meters (98 feet) from the high tide mark. Grenada, in 1983 had a Physical Tourism Development Plan funded by the Organization of American States. From this study, a coastal monitoring program was begun in August 1985. One of the four major tasks of the program, if funding is received, will be to set up additional tide gauges, and initiate long-term sea-level measurements. It is further hoped that a recommended 50-meter (164- foot) development setback policy will be legislated and implemented in the near future. Custavia, St. Barthelemy, French West Indies, representative of the low-lying coastal towns found throughout the Caribbean. (Photo by the author) Tide-Gauge Stations f\ network of tide-gauge stations is essential to the monitoring of Caribbean sea-level change. The list below includes many of the existing tide gauge stations in the Caribbean and those proposed by a workshop on Physical Oceanography and the Climate of the Caribbean Sea and Adjacent Regions, held in Cartagena, Colombia, in August 1986, under the auspices of the United Nations Inter- governmental Oceanographic Commission. EXISTING Port Isabel, Texas Miami Beach, Fla. Key West, Fla. Havana, Cuba Cape San Antonio, Cuba Tampico, Mexico Tuxpan, Mexico Veracruz, Mexico Alvarado, Mexico Coatzacoalcos, Mexico Carmen, Mexico Progreso, Mexico Chetumal, Mexico Port Cortes, Honduras Port Castilla, Honduras Limon, Costa Rica Cristobal, Panama Cumana, Venezuela Chaguaramas, Trinidad Port of Spain, Trinidad San |uan, Puerto Rico Magueyes, Puerto Rico Port Plata, Dominican Republic Port au Prince, Haiti Port Royal/Kingston, Jamaica Cuantanamo Bay, Cuba PROPOSED Port Morelos, Mexico Carapachibe, Cuba Grand Cayman Cape Cruz, Cuba Montego Bay, Jamaica Savanna-La Mar, Jamaica Swan Isle, Honduras Morant Cay, Jamaica Pedro Cay, Jamaica Serranilla, Colombia San Andres Isle, Colombia Colon, Panama Cartegena, Colombia Riohacha, Colombia La Orchila, Venezuela Toco, Trinidad Crown Point, Tobago Charlotteville, Tobago Kingston, St. Vincent Georgetown, Grenada Bridgetown, Barbados Castries, St. Lucia Fort de France, Martinique Roseau, Dominica Basse Terre, Guadaloupe St. Croix, U.S.V.I. Mona Is., Puerto Rico Isla Saona, Dominican Republic Cape Du Mole, Haiti Cape Maisi, Cuba Caribbean Research Agenda As a response to the concern expressed in the Caribbean region about the implications of expected natural and man-induced climatic changes for the marine and coastal environment, the United Nations Environment Programme has initiated a study to review the situation in the Caribbean through their Regional Seas Program. Some of the intended objectives of the study include an examination of the possible effects of sea-level changes on the coastal ecosystems, including but not limited to, deltas, estuaries, coral reefs, beaches, and wetlands. Another objective is to determine areas or systems that appear most vulnerable to the projected climate changes and related effects. A meeting held at Kingston, Jamaica, on July 30 to August 1, 1987, established a Task Team on Implications of Climatic Changes in the Caribbean Region. The author and other researchers at the Woods Hole Oceanographic Institution are involved in this Task Team, which will prepare a report on the expected effects and associated areas of climatic changes in the region. Recommendations for policy development also will be forthcoming for preparation of legislation, and for organizational development. With many countries in the Caribbean, these recommendations will not be easy to implement. Other studies are being conducted in the Caribbean Sea and adjacent areas. The United Nations Educational, Scientific, and Cultural Organization (UNESCO) Lesser Antilles Coastal Zone Management and Beach Stability Program, which began in February of 1985, covers Antigua, Dominica, Grenada, St. Lucia, St. Vincent, and St. Christopher and Nevis. The aim of this project is to assist in developing internal capabilities to manage and conserve, for socio-economic benefits, the beach and nearshore resources. One of the recommendations put forth was to implement a system of tide gauges at each island in the Caribbean. About two or three tide gauges per island are believed to be required to determine local relative sea-level changes. 55 Another project, under the auspices of the United Nations Intergovernmental Oceanographic Commission (IOC), held a workshop on Physical Oceanography and the Climate of the Caribbean Sea and Adjacent Regions in Cartagena, Colombia, in August, 1986. The goal of the workshop was to convene a small working group of physical oceanographers from the Caribbean region for the purpose of designing a research agenda. One of the projects proposed was an open-sea and coastal network of sea level and weather stations to contribute data on both an island scale and basin scale. The interests of many area states were primarily in the economic and applied aspects of shelf and coastal processes, and a sea-level project was felt to be essential to these interests. Management of Caribbean coastal areas has been hindered by the general lack of knowledge about coastal ecosystems, and by the shortage of expertise in coastal management issues and policy. To address these problems, the United Nations is taking the initiative to alert countries in the Caribbean to the possible implications of sea-level changes through various workshops and meetings. Funds are initially needed to implement coastal research studies in order to improve coastal management programs in the region. Hopefully the United Nations effort will lead not only to an improved understanding of the problems caused by sea-level rise, but also the allocation of much- needed resources to assist the Caribbean nations in their management efforts. Frank Gable is a Geographer with the Marine Policy and Ocean Management Center at the Woods Hole Oceanographic Institution. Selected References Bruun, P. 1962. Sea-level rise as a cause of shore erosion. ASCE lournal Waterways and Harbors Division. 88:1 1 7-1 30. Cambers, C. 1987. Coastal zone management programmes in Barbados and Grenada. In, Coastal Zone '87, ed. Orville Magoon, pp. 1384-1394. New York: American Society of Civil Engineers. Carbognin, L. 1985. Land subsidence: a worldwide environmental hazard. Nature and Resources 21:2-12. Clark, |. R., ed. 1985. Coastal Resources Management: Development Case Studies. 749 pp. Columbia, SC: Research Planning Institute, Inc. Hoffman, J. S., D. Keyes, and J. Titus 1983. Projecting Future Sea- Level Rise, Methodology, Estimates to the Year 2700, and Research Needs. Washington, DC: United States Environmental Protection Agency. Lemonick, M. D. 1987. Shrinking shores: overdevelopment, poor planning and nature take their toll. Time 1 30:38-47. Millemann, B. 1986. And Two If By Sea. 109 pp. Washington, D.C.: Coast Alliance Inc. Titus, J. C., ed. 1986. Effects of Changes in Stratospheric Ozone and Global Climate. 1 184 pp. Washington, DC: United States Environmental Protection Agency. U.S. Agency for International Development. 1987. Caribbean Marine Resources: Opportunities for Economic Development and Management. Washington, DC: U.S. Department of Commerce. ROYAL METEOROLOGICAL SOCIETY Call for Journal Papers — Physical Oceanography and Meteorology The Royal Meteorological Society was founded in 1 850 for "the advancement of meteorological science." Its Quarterly Journal which was first published in 1871 is generally recognized as being among the world's leading scientific journals, and is distributed to over 75 countries throughout the world. It is now apparent that interest in air-sea interaction and combined ocean-atmosphere models will increase, and the Society is making space available in the Quarterly Journal to accommodate more papers on these subjects. The Society invites authors of papers on physical oceanography, oceanic dynamics, air-sea interaction, ocean-atmosphere models or other related subjects to submit them for considera- tion for publication in the Quarterly Journal which has already a wide circulation amongst oceanographers. There are no page charges and submission of papers is not restricted to members of the Society. The Quarterly Journal of the Royal Meteorological Society will be printed in January (two parts), April, July (two parts), and October every year. The price in 1988 will be £95 or US $167. Reduced rates are available to individuals who are members of the Society. Papers and orders should be sent to the Executive Secretary, Royal Meteorological Society, James Glaisher House, Grenville Place, Bracknell, Berks, RG12 1BX. 56 Changing Times for Caribbean Fisheries by Mel Goodwin