TEXAS TECH UNIVERSITY

Natural Science Research Laboratory

Occasional Papers

Museum of Texas Tech University

Number 285 25 March 2009

A Survey of Bats in Northern Trinidad Late in the Rainy Season

Keith Geluso, MaryJ. Harner, Cliff A. Lemen, and Patricia W Freeman

Abstract

Located off the northeastern coast of Venezuela, Trinidad is a small tropical island with a
rich diversity of bats. Although 66 species have been documented, few inventories have pub¬
lished information on community structure of bats in the diverse habitats of the island. Here
we report on composition, abundance, and natural history of species captured primarily in the
Northern Range at the end of the rainy season (late December - early January). We captured
789 individuals representing 30 species in six families, including 672 bats in nets at ground level
and 117 associated with roosts. Our capture rates in ground-level mist nets were substantially
higher than other surveys reported from Trinidad. In ground-level nets, Carolliaperspicillata ,
Artibeus jamaicensis, Uroderma bilobatum , Platyrrhinus helleri, and A. glaucus composed
79.8% of captures, and those species were present at most sites. Bats in the family Phyllos-
tomidae accounted for 91% of captures and 59% of species. By feeding guild, captures were
comprised of frugivores (86%), aerial insectivores (7%), nectarivores (3%), omnivores (3%),
and gleaning animalivores (2%). We observed reproductive activity in only seven species, but
this represents new seasonal information for Trinidad. Our study reports on the natural history
of Trinidad’s unique and diverse chiropteran fauna during a time of year when little information
is available.

Keywords: bats, Northern Range, reproduction, species abundance, species composition,
Trinidad

Introduction

Trinidad is a relatively small tropical island
(4,769 km 2 ) in the Caribbean with a rich diversity of
bats (66 species; Clarke et al. 2005b), including nearly
half of the 146 species of Neotropical bats (Simmons
and Voss 1998). Located about 11 km northeast of
the Venezuelan coast, Trinidad has been connected to
mainland South America by land bridges at least five
times in the past 140,000 years (see Murphy 1997).

Many genera from South America, including Cho-
eroniscus, Desmodus, Diclidurus, Furiptera , Mimon,
Rhynchonycteris, Thyroptera , Tonatia, Trachops ,
Uroderma , and Vampyrum, occur on Trinidad but not
farther northward on Tobago or islands in the Lesser
Antilles (i.e., excluding fossil records; Goodwin and
Greenhall 1961; Baker and Genoways 1978; Koopman
1989). Larger Caribbean islands are depauperate in di-

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Occasional Papers, Museum of Texas Tech University

versity of bats relative to Trinidad; Cuba (110,860 km 2 )
and Hispaniola (76,480 km 2 ) only have 26 and 18 spe¬
cies, respectively (Genoways et al. 2005). Trinidad’s
diverse chiropteran fauna has been attributed to both
its historical connection to South America and overall
ecological richness (Koopman 1958; Genoways et al.
1998). Genoways et al. (1998) proposed a zoogeo¬
graphic boundary of chiropteran fauna that separates
species with origins in the West Indies from those
in South America; this is referred to as “Koopman’s
Line.” The islands of Trinidad, Tobago, and Grenada
lie south of Koopman’s Line because their chiropteran
fauna originated in South America and lacks endemic
species known from the Lesser Antilles.

Trinidad contains a variety of habitats, including
rainforests, deciduous forests, swamps, marshes, agri¬
cultural areas, and urban areas (Beard 1946; Goodwin
and Greenhall 1961). Three mountain ranges traverse
the width of the island, with the most expansive range
located in northern Trinidad, the Northern Range. The
tallest peak, El Cerro del Aripo, is located in the North¬
ern Range at an elevation of 940 m. Trinidad has two
seasons - a rainy season May - December and a dry
season January - May (Goodwin and Greenhall 1961;
Clarke and Downie 2001). Annual rainfall varies from
356 cm in northeastern portions of the Northern Range
to 127 cm in western parts of the island (Goodwin and
Greenhall 1961). Although the island contains about
1.25 million people, many forested regions remain
across the country.

Researchers have conducted surveys of Trinidad’s
bats for over a century. Goodwin and Greenhall (1961)
first summarized the diversity and ecology of 58 spe¬
cies from the island. Subsequent surveys recorded

several additional species, as well as aspects of their
natural history (Goodwin and Greenhall 1962, 1964;
Genoways et al. 1973; Carter et al. 1981; Clarke and
Racey 2003). Furthermore, the island has been a field
site for research of chiropteran behavior (e.g. Kunz
and McCracken 1996; Kunz et al. 1998; Davidson
and Wilkinson 2004) and physiology (e.g. Heideman
et al. 1992; Rasweiler and Badwaik 1997; Porter and
Wilkinson 2001). Recently, researchers have addressed
applied questions, including how bats respond to trails
or logging in forests (Clarke and Downie 2001; Clarke
et al. 2005a, 2005b).

Trinidad is undergoing rapid economic growth,
fueled by the country’s rich supplies of natural re¬
sources (e.g. petroleum and natural gas). As agriculture
and urban development expand into montane regions,
bats will be affected by habitat alterations as they have
elsewhere (Fenton et al. 1992; Wilson et al. 1996;
Medellin et al. 2000). Few inventories in Trinidad,
however, contain information on structure of bat com¬
munities. Therefore, we present this paper as a refer¬
ence for community structure of bats from northern
Trinidad at the end of the rainy season. We conducted
surveys in late December and early January, a period
when few records have been reported for the island.
We present data on community composition and rates
of capture, as well as provide details on reproductive
activity, morphology, and distribution. As stressed by
Simmons and Voss (1998), it is important for all bat
researchers to archive information about methods and
captures so that baseline information about communi¬
ties is available. Therefore, our main objective was to
contribute information for future comparative studies
involving this diverse chiropteran fauna.

Methods

From 20 December 2007 to 1 January 2008, we
captured bats by various techniques at 10 locations
in northern Trinidad (Fig. 1, Appendix). Seven sites
were in the Northern Range, and three were in lowlands
between the Northern and Central ranges. Coordinates
of localities were determined with hand-held global
positioning systems (GPS; Garmin GPS 12, Garmin
International, Inc., Olathe, KS, USA) using North
American Datum 1983. Elevations were determined

by plotting coordinates in Google Earth (v3.0; http://
earth.google.com). General descriptions of habitats at
sites are provided in the Appendix.

For most field efforts, we deployed mist nets
ranging in length from 2.6 to 18 m (Avinet Inc., Dry den,
NY, USA) at ground level along roadways and trails in
forests, over watercourses, in plantations, and around
buildings where we expected bats to occur. Details of

Geluso et al.—Bats in Northern Trinidad

3

Figure 1. Map of capture sites for bats in northern Trinidad, West Indies from 20 December
2007 to 1 January 2008. For precise locations, see corresponding numbers in the Appendix.

the number of nets, net lengths, and hours of deploy¬
ment are included in the Appendix. When sampling
roost sites located in buildings, we used small hand
nets to capture bats as they roosted or as they exited
the roost. An additional bat was captured during the
day on 20 December with a hand net, while it foraged
in an unobstructed flyway above a roadway.

We deployed mist nets before dusk and monitored
them continually for <6.5 h. On two nights at the Wil¬
liam Beebe Field Station, we reopened and monitored
nets for about 1.5 h before dawn—once because heavy
rains hampered efforts during the night and once to at¬
tempt to capture individuals in the early morning. We
identified individuals to species and held individuals
in soil sample bags (12.7 x 17.8 and 8.9 x 12.7 cm,
Hubco Protexo and Sentry sample bags, Hutchinson
Bag Corp., Hutchinson, KS, USA) for <1 h. On most
nights, we marked individuals with a spot of black
ink before release to determine whether subsequent

captures that evening represented new individuals
or recaptures. All data hereafter represent unique
individuals; we occasionally recaptured individuals
but did not keep track of those data in field notes. For
many individuals we recorded sex, length of forearm,
body weight, age (adult or young based on cartilage
in epiphyses in wings), and reproductive status. Body
weights reported herein represent only those measured
in the field shortly after capture as we collected data on
bite-force for many individuals shortly after removal
from mist nets (Freeman et al. in preparation). For
data regarding bite-force, we used equipment and
followed procedures outlined by Freeman and Lemen
(2008). Once we obtained sufficient data on bite force
for a species, subsequent individuals were released im¬
mediately after removing them from mist nets without
measurement of body weight and length of forearm or
recording sex, age, and reproductive status. Most bats
were released at site of capture in < 30 min, but a few
individuals were kept overnight to retest bite force, pho-

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Occasional Papers, Museum of Texas Tech University

tograph, verify species, or retain as voucher specimens.
Voucher specimens of each species were prepared as
standard skins and skeletons. Specimens and field
notes are archived in natural history collections in the
Division of Zoology, University of Nebraska State
Museum, Lincoln, NE, USA.

We followed Simmons and Voss (1998) for
identification of some species and assignment to gen¬
eral feeding guilds. Other regional field guides were
used for aid in identification of species (Goodwin and

Greenhall 1961; Eisenberg 1989; Reid 1997; Gardner
2007). Capture rates were reported as bats captured per
10 net-meter-hours, that is, number of bats captured per
1 m of net per 10 hrs, or equally, bats captured per 10 m
of net per hr, following methods reported by Simmons
and Voss (1998). Descriptive statistics were calculated
in SPPS version 12 (Chicago, IL, USA). Extreme out¬
liers (> 3 x interquartile range from 1 st or 3 rd quartile)
were removed from analyses because they likely reflect
errors in collecting and recording data.

Results

We captured 789 individuals representing 30
species, including 672 bats in nets near ground level
(Table 1) and 117 associated with roosts (Table 2). We
deployed 44 mist nets at ground level (not associated
with roosts) for a cumulative 2,239 net-meter-hours
(net-m-hr) and captured 3.0 bats/10 net-m-hr. In
ground-level nets, Carollia perspicillata, Artibeus ja-
maicensis, Uroderma bilobatum, Platyrrhinus helleri,
and Artibeus glaucus composed 79.8% of bats, and
those species were present at most sites. Five other
species were caught at >50% of sites, including Chiro-
derma villosum, Glossophaga soricina, Phyllostomus
hastatus, Sturnira lilium, and Sturnira tildae. The
one individual captured in a hand net was Saccopteryx
leptura. We captured bats representing six families
in ground-level nets (Emballonuridae, Mormoopidae,
Phyllostomidae, Thyropteridae, Vespertilionidae, and
Molossidae), with Phyllostomidae accounting for
91% of captures and 59% of species (17 of 29 species,
Table 1). Frugivores (86%, 576 individuals) were most
abundant, followed by aerial insectivores (7%, 44),
nectarivores (3%, 19), omnivores (3%, 17), and glean¬
ing animalivores (2%, 16; Table 1). Ten species were
captured rarefy (< 0.5% of total captures) in mist nets
(Table 1). We observed eight species in a total of 10
roost sites in various natural and man-made structures
(Table 2). Of note, Pteronotus parnellii was observed
roosting in a large and abandoned, two-story concrete
building that contained many large rooms with little or
no sunlight; individuals were observed hanging from
ceilings in a number of rooms. In this building, we also
captured C. perspicillata, Mormoops megalophylla, and
P. hastatus. We summarized details of body weight and
length of forearms for each species captured (Table 3).

Of note, all 11 Micronycteris megalotis were male. We
observed both males and females for all other species
where we recorded the sex for >2 individuals.

We observed seven species with evidence of cur¬
rent or recent reproductive efforts ( Anoura geoffroyi,
Molossus molossus, Phyllostomus discolor, Rhyn-
chonycteris naso, S. lilium, S. tildae, and Vampyrodes
caraccioli). On 24 December, we captured a lactating
A. geoffroyi, and on 1 January, we captured two preg¬
nant females; one contained a fetus with crown-rump
(CR) length of 26 mm. On 26 December and 1 Janu¬
ary, we captured pregnant individuals of P. discolor,
the female in December contained a single fetus with
CR of 20 mm. On 24 December, we captured pregnant
females of S. lilium and S. tildae', each contained a
single fetus (CR = 28.5 and 20 mm, respectively). On
31 December, a female V caraccioli had a single fetus
with CR of 18 mm. We captured flying young of M.
molossus (26 December) and R. naso (29 December).
One adult male R. naso had enlarged testes that mea¬
sured 7x4 mm on 29 December.

We observed two species with brown and orange
color morphs (C. perspicillata and Pteronotus parnel¬
lii). Abundance of orange-colored individuals of C.
perspicillata varied between two neighboring valleys in
the Northern Range. In the Arima Valley, we captured
only a single orange morph out of 105 individuals, but
we captured about 10 orange-colored individuals of
various shades out of 59 individuals at one site in the
Guanapo Valley.

Geluso et al.—Bats in Northern Trinidad

5

Table 1. Species of bats captured in nets near ground level (mist nets and hand net) not associated
with roosts in northern Trinidad 20 December 2007-1 January 2008. Feeding guild, number of each
species, percentage of total individuals, and number of sites where each species was captured (8 sites
total are possible) also are reported. Captures of bats at the William Beebe Field Station on 5 nights
represent a single site.

Species

Feeding guild 1

Number of
individuals

Percentage of
individuals

Number
of sites

Carollia perspicillata

F

295

43.9

8

Artibeus jamaicensis

F

88

13.1

5

Uroderma bilobatnm

F

87

12.9

8

Platyrrhinus helleri

F

46

6.8

5

Artibeus glaucus

F

21

3.1

6

Pteronotus parnellii

AI

13

1.9

4

Chiroderma villosum

F

13

1.9

5

Micronycteris megalotis

GA

12

1.8

4

Sturnira lilium

F

12

1.8

5

Phyllostomus hastatus

OM

11

1.6

5

Anoura geoffroyi

N

11

1.6

2

Glossophaga soricina

N

8

1.2

5

Rhynchonycteris naso

AI

8

1.2

1

Sturnira tildae

F

8

1.2

5

Molossus molossus

AI

6

0.9

2

Phyllostomus discolor

OM

6

0.9

4

Saccopteryx bilineata

AI

5

0.7

2

Artibeus lituratus

F

4

0.6

3

Saccopteryx leptura

AI

4

0.6

3

Mormoops megalophylla

AI

3

0.4

2

Pteronotus davyi

AI

2

0.3

2

Trinycteris nicefori

GA

2

0.3

2

Chiroderma trinitatum

F

1

0.1

1

Eptesicus brasiliensis

AI

1

0.1

1

Micronycteris minuta

GA

1

0.1

1

Mimon crenulatum

GA

1

0.1

1

Myotis nigricans

AI

1

0.1

1

Thyroptera tricolor

AI

1

0.1

1

Vampyrodes caraccioli

F

1

0.1

1

TOTAL

672

99.4

'Feeding guilds: AI, aerial insectivore; F, frugivore; N, nectarivore; GA, gleaning animalivore; and
OM, omnivore.

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Occasional Papers, Museum of Texas Tech University

Table 2. Species of bats captured associated with roosts in northern Trinidad 21 December 2007-1 January 2008.

Species

Number of
individuals

Number of roosts
observed

Type of structure

Molossus molossus

57

3

narrow attic of buildings

Carollia perspicillata

15

6

large concrete building, small building with dark
areas, small cave, and hollow tree

Molossus ater

13

1

narrow attic of residential building

Mormoops megalophylla

12

1

large concrete building

Phyllostomus hastatus

10

2

large concrete building, hollow tree

Pteronotus parnellii

8

1

large concrete building

Glossophaga soricina

1

1

small cave

Saccopteryx bilineata

1

1

small building with open doors and windows

Table 3. Mean body weight (g) and mean length of forearms (mm) of bats in northern Trinidad 20
December 2007 - 1 January 2008. Body weights represent only those measured in the field shortly
after capture. Numbers in parentheses represent sample size, and numbers below means represent
minimum-maximum values.

Bodv weight

Length of forearm

Species

male

female

male

female

Anoura geoffroyi

14.1 (4)

15.7 (6)

41.5 (4)

42.8 (5)

12.5-16.0

14.0-18.0

40.0-43.0

39.0-45.0

Artibeus glaucus

13.5 (5)

13.8 (10)

40.2 (5)

41.3 (8)

11.5-15.0

11.0-16.0

39.0-42.0

40.0-43.0

Artibeus jamaicensis

37.3 (9)

42.8 (3)

56.4 (9)

58.4 (5)

34.0-41.5

36.0-46.5

55.0-58.0

55.0-61.0

Artibeus lituratus

70.0 (3)

70.0 (1)

70.0 (3)

73.0 (1)

66.0-77.0

-

66.0-75.0

-

Carollia perspicillata

16.3 (14)

16.9 (13)

41.6 (17)

41.6 (11)

11.0-20.0

14.0-20.0

39.0-44.0

40.0-43.0

Chiroderma trinitatum

-

18.0 (1)

-

41.0 (1)

Chiroderma villosum

25.6 (7)

28.0 (4)

47.4 (7)

48.5 (4)

23.0-30.0

26.0-30.0

45.0-50.0

48.0-49.0

Eptesicus brasiliensis

-

9.0 (1)

-

43.0 (1)

Glossophaga soricina

9.3 (5)

10.3 (2)

35.5 (4)

35.5 (2)

8.5-10.0

8.5-12.0

35.0-36.0

35.0-36.0

Mimon crenulatum

11.5 (1)

-

48.0 (1)

-

Micronycteris megalotis

6.1 (9)

—

33.7 (10)

—

5.0-7.0

—

31.0-35.0

—

Geluso et al.—Bats in Northern Trinidad

7

Table 3. (cont.)

Body weight Length of forearm

Species male female male female

Micronycteris mimita

6.0 (1)

-

34.0 (1)

-

Molossus ater

20.8 (2)

22.6 (9)

48.5 (2)

48.3 (9)

19.0-22.5

21.0-24.0

48.0-49.0

48.0-50.0

Mormoops megalophylla

15.5 (2)

16.0 (3)

58.0 (2)

57.2 (3)

15.0-16.0

16.0-16.0

57.0-59.0

56.6-58.0

Molossus molossus

11.7 (17)

9.5 (21)

38.6 (17)

37.6 (20)

9.0-14.2

7.5-11.5

37.0-40.5

35.0-39.0

Myotis nigricans

4.0 (1)

-

36.0 (1)

-

Phyllostomus discolor

34.9 (4)

33.5 (2)

60.4 (4)

61.0 (2)

31.0-39.0

31.0-36.0

58.5-61.0

60.0-62.0

Phyllostomus hastatus

85.1 (5)

-

82.3 (6)

82.0 (2)

80.0-93.0

-

81.0-84.0

80.0-84.0

Platyrrhinus helleri

13.0 (11)

13.3 (7)

38.6 (11)

39.0 (8)

11.0-15.5

9.5-16.0

35.0-41.0

38.0-40.0

Pteronotus davyi

—

10.5 (2)

—

47.5 (2)

-

10.0-11.0

-

47.0-48.0

Pteronotus parnellii

21.2 (6)

19.0 (7)

61.5 (6)

61.3 (8)

19.5-23.0

16.5-26.5

61.0-63.0

58.0-63.0

Rhynchonycteris naso

3.9 (4)

4.0 (1)

37.0 (4)

38.0 (1)

3.5-4.0

-

36.0-38.0

-

Saccopteryx bilineata

7.5 (2)

7.5 (1)

47.5 (2)

47 (1)

12-1.1

-

47.0-48.0

-

Saccopteryx leptura

4.6 (3)

—

39.3 (3)

—

4.4-5.0

-

39.0-40.0

-

Sturnira lilium

19.5 (2)

19.3 (8)

43.0 (2)

42.5 (9)

19.0-20.0

13.0-24.0

42.5-43.5

41.0-44.0

Sturnira tildae

24.2 (3)

23.4 (5)

46.3 (3)

45.8 (5)

20.5-27.0

21.5-24.5

45.0-47.0

45.0-46.0

Thyroptera tricolor

-

3.2 (1)

-

35.0 (1)

Trinycteris nicefori

11.8 (1)

-

38.5 (1)

-

Uroderma bilobatum

16.6 (9)

17.4 (17)

41.4 (9)

43.0 (16)

12.5-19.0

11.5-20.5

39.0-44.0

41.0-46.0

Vampyrodes caraccioli

-

33.0 (1)

-

50.0 (1)

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Occasional Papers, Museum of Texas Tech University

Discussion

We captured 672 bats representing 29 species in
ground-level nets in only 11 nights (Table 1), represent¬
ing an unusually large number of captures. Our capture
rates (3.0 bats/10 net-m-hr) were greater than those in
Mora forests of southern Trinidad (0.5 bats/10 net-m-
hr, Clarke and Downie 2001; 0.5-2.2 bats/10 net-m-hr,
Clarke et al. 2005a, 2005b) and rainforests of Paracou,
French Guiana (0.98 bats/10 net-m-hr; Simmons and
Voss 1998). Our high rates of capture may reflect
greater abundances or seasonal differences of bats in the
Northern Range compared to Mora forests in southern
Trinidad. We rapidly accumulated a high diversity
of species because of our high frequency of captures
(Fig. 2). Rates of species accumulation were similar to
surveys in primary forests of southern Trinidad (Clarke
et al. 2005b) and to surveys across all habitats in Para¬
cou (Simmons and Voss 1998), based on numbers of
individuals captured in ground-level nets. By sampling
with ground-level nets, we missed capturing species
active above the canopy or that readily sense and avoid
nets, including some Emballonurids, Phyllostomines,
and Molossids (Simmons and Voss 1998). Additional
surveys in northern Trinidad that include searching for
roosts (Carter et al. 1981), using high nets (Simmons
and Voss 1998), and increasing nights of effort would
yield more species in the area.

Carollia perspicillata dominated our captures
(44%), as it has in other surveys on Trinidad (Clarke and
Downie 2001; Clarke et al. 2005a, 2005b). However,
we commonly captured several species, A. jamaicen-
sis, U. bilobatum , and P. helleri, that were captured
infrequently in Mora forests of southern Trinidad, but
we rarely captured G. soricina, a species captured fre¬
quently in southern Trinidad (Clarke and Downie 2001;
Clarke et al. 2005a, 2005b). Dominance of frugivores
in our captures from the Northern Range may reflect
an abundance of food and roosting sites in this region.
In addition, we sampled during a rainy season with
relatively low precipitation (Howard Nelson, personal
communication), which may have influenced levels
of activity or distribution of bats across Trinidad. It
is unknown whether bats move seasonally throughout
Trinidad or migrate to and from Venezuela.

Reproduction .—Few data are available for re¬
productive activity of bats in Trinidad at the end of the
rainy season (December and early January). Seven spe¬
cies were reproductively active during our survey (A.
geoffroyi , M. molossus, P. discolor , R. naso, S. lilium,
S. tildae , and V caraccioli). These records expand the
known dates of reproductive activity for these seven
species on the island. Pregnant females of A. geoffroyi
were documented previously from late August to mid
December (Goodwin and Greenhall 1961; Heideman
et al. 1992). This species also appears to give birth late
in the wet season in Trinidad (this study), as it does in
other Neotropical regions (Wilson 1979). Molossus
molossus has been reported pregnant in July and Au¬
gust and lactating August, September, and December
on the island (Goodwin and Greenhall 1961; Carter et
al. 1981). Our capture of a volant young M. molossus
near the end of December is at the same time of year
when lactating females were captured by Goodwin and
Greenhall (1961). Pregnant females ofP discolor are
known from February, March, June, and August (Good¬
win and Greenhall 1961). Our data expand known dates
of pregnancy for P. discolor on Trinidad and suggest
this species exhibits an acyclic or continuous pattern
of breeding, as documented in other parts of its distri¬
bution (Wilson 1979). Pregnant females of R. naso
have been documented in March, July, and August in
Trinidad (Goodwin and Greenhall 1961; Carter et al.
1981). Our capture of a volant young R. naso on 29
December suggests that additional surveys will docu¬
ment pregnant females later into the wet season. For
S. lilium , the only previous record of a reproductively
active female was a pregnant individual captured in Au¬
gust (Carter et al. 1981). Pregnant females of S. tildae
have been reported in March (Goodwin and Greenhall
1961) and August (Carter et al. 1981). Our captures of
pregnant females in December expand known dates of
pregnancy for both S. lilium and S. tildae on the island.
Further data are needed to comment on the reproduc¬
tive patterns of both species on Trinidad. Capture of a
pregnant V caraccioli in the Northern Range represents
the first documentation of reproduction for this species
for Trinidad. Observations of pregnant individuals
in dry and rainy seasons in other Neotropical regions

Geluso et al.—Bats in Northern Trinidad

9

Number of nights

0 100 200 300 400 500 600 700

Number of captures

Figure 2. Species accumulation curves for bats captured in northern
Trinidad in ground-level mist nets based on number of captures (bottom
axis) and number of nights (top axis) from 21 December 2007 to 1
January 2008. Data do not include individuals or species captured in
roosts or the single individual captured by a hand net not associated
with a roost.

suggest V. caraccioli exhibits a pattern of bimodal
polyestry exhibited by many tropical species of bats
(Wilson 1979).

Comments on Prior Research Expeditions to
Trinidad. —Carter et al. (1981) reported on the distribu¬
tion, reproduction, and morphology of bats collected as
voucher specimens from three surveys on Trinidad in
the late 1970s. We contacted R. J. Baker (Texas Tech
University, Lubbock, Texas, USA) to obtain further
details of those surveys because the authors did not
present details of field efforts or whether individuals
reported represented all captures. We learned that many
individuals of a number of species were released and
efforts consisted of searching for roosts as well as de¬
ploying mist nets. Thus, specimens examined in their
manuscript reflect species richness, but not abundances
of individuals, at sites across Trinidad.

Conclusions. —Our intent was to report on com¬
munity structure and notes on natural history from a
time of year when few surveys have been conducted on
an island where economic development is increasing
because of a rich supply of petroleum in the region.
Our limited survey was not intended to explain the
complete community of bats in the Northern Range.
However, by publishing details of our survey, we aim
to assist future researchers in conducting comparative
studies within Trinidad, as well as across the Neotrop¬
ics. All field studies potentially contain important data
on natural history that could be gleaned for publication,
as ours did. Trinidad provides a location to examine
community structure and interactions among a unique
cohort of Neotropical bats.

10

Occasional Papers, Museum of Texas Tech University

Acknowledgments

John Rasweiler (State University of New York
Downstate Medical Center) graciously shared his
knowledge of “where to go for what” in Trinidad. We
thank Simeon (Patsy) Williams for his knowledge re¬
garding flora and fauna of Trinidad, Ronnie Hernandez
(Beebe Tropical Field Station [= Simla], Manager)
for matters associated with Simla, Howard Nelson
(Chief Executive Officer, Asa Wright Nature Center)
for information about Asa Wright, David Boodoo
(Wildlife Section, Ministry of Public Utilities and the
Environment) for assistance with wildlife permits,
Bhim Ramoutar (Ministry of Agriculture, Land and
Marine Resources) for assistance with export permits,

and Steve Thomas (University of Nebraska-Lincoln
[UNL]) for providing information regarding traveling
and working at Simla. We also thank many residents
of Trinidad for their gracious hospitality in granting
us permission to capture bats on their property. Angie
Fox (UNL) prepared Fig. 1. Kenneth Geluso and two
anonymous reviewers improved earlier versions of
the manuscript. Funding for this project was obtained
by PWF through the University of Nebraska-Lincoln
Research Council and University of Nebraska State
Museum. This project was conducted in accordance
with and approved by the Institutional Animal Care and
Use Committee at UNL.

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Carter, C. H., H. H. Genoways, R. S. Loregnard, and R. J.
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Addresses of authors :

Keith Geluso

Department of Biology
University of Nebraska—Kearney
Kearney, NE 68849 USA
gelusokl@unk. edu

Mary J. Harner

Department of Biology
University of Nebraska—Kearney
Kearney, NE 68849 USA
harnermj@unk. edu

11

in Neotropical rainforests. Conservation Biology
14:1666-1675.

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Tobago. Krieger Publishing Company, Malabar,
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Cliff A. Lemen

School of Natural Resources and
University of Nebraska State Museum
428 Hardin Hall
University of Nebraska—Lincoln
Lincoln, NE 68583-0974 USA
clemen2@unl. edu

Patricia W. Freeman

School of Natural Resources and
University of Nebraska State Museum
428 Hardin Hall
University of Nebraska—Lincoln
Lincoln, NE 68583-0974 USA
pfreemanl@unl. edu

12

Occasional Papers, Museum of Texas Tech University

Appendix

Localities of capture sites for bats in northern Trinidad 20 December 2007-1 January 2008. Parishes are given
in all capitals. Dates of capture are followed by parentheses that contain the number and size of nets (or type,
i.e., hand nets) deployed; general habitats; cumulative meter-net-hours; and number of each species captured.
Abbreviations for species are as follows: Anoura geoffroyi (ANGE), Artibeus glaucus (ARGL), A. jamaicensis
(ARJA), A. lituratus (ARLI), Carollia perspicillata (CAPE), Chiroderma trinitatum (CHTR), C. v Mo sum (CHVI),
Eptesicus brasiliensis (EPBR), Glossophaga soricina (GLSO), Micronycteris megalotis (MIME), M. minuta
(MIMI), Mimon crenulatum (MICR), Molossus ater (MOAT), M. molossus (MOMO), Mormoops megalophylla
(MOME), Myotis nigricans (MYNI), Phyllostomus discolor (PHDI), P. hastatus (PHHA), Platyrrhinus helleri
(PLHE), Pteronotus davyi (PTDA), P. parnellii (PTPA), Rhynchonycteris naso (RYNA), Saccopteryx bilineata
(SABI), S. leptura (SALE), Sturnira lilium (STLI), S. tildae (STTI), Thyroptera tricolor (THTR), Trinycteris
nicefori (TRNI), Uroderma bilobatum (URBI), and Vampyrodes caraccioli (VAC A). Catalog numbers of voucher
specimens at the University of Nebraska State Museum (UNSM) are given in brackets. Numbers in bold before
localities refer to numbers in Fig. 1.

ST. ANDREW: (1) Cumaca Road, lOMl^N, 061°09.771'W, 319 m elev. (along edge of rainforest), 27
December (one 2.6-m in front of small cave; 13 m-net-h; CAPE 5, GLSO 1), 27 December (one 9-m, two 18-m;
225 m-net-h; ARGL 5, CAPE 37, PHHA 1, SALE 1, STLI 6, STTI 2, URBI 15); ( 2 ) N of Cumuto, Aripo River,
10°36.052'N, 061° 12.78l'W, 34 m elev. (near and over river), 28 December (two 12-m, two 18-m; 210 m-net-h;
ARGL 2, CAPE 17, GLSO 1 [UNSM 29134], SALE 1, MOME 2, MOMO 3 [UNSM 29135], PLHE 2 [UNSM
29136], PTDA 1 [UNSM 29133], STLI 1, URBI 9 [UNSM 29137]); ( 3 ) S of Waller Field, 2 kmN of Cumuto,
10°36.035H 061°12.850'W, 35 m elev. (building in lowlands), 22 December (hand nets; CAPE 10, MOME 12
[UNSM 29102, 29104], PHHA 10 [UNSM 29103, 29105], PTPA 8); and ( 4 ) 0.2 km E of Cumuto Road on Little
Coora Road, 10°33.806'N, 061°11.494'W, 48 m elev. (building in low hills), 23 December (hand nets; MOAT 13
[UNSM 29127, 29128, 29129, 29130], MOMO 5 [UNSM 29131]).

ST. GEORGE: ( 5 ) Yarra River, SE of Filette, 10°47.875H 061°21.005'W, 13 m elev. (near and over river
and in small plantation), 29 December (one 12-m, three 18-m; 297 m-net-h; ARJA 1 [UNSM 29144], CAPE 34
[UNSM 29145], CHVI 2, GLSO 2 [UNSM 29141], MIME 2 [UNSM 29142, 29143], MOME1, PHDI 1, PTPA
6 [UNSM 29146], RHNA 8 [UNSM 29138, 29139, 29140], URBI 4); (6) Brasso Seco Village, 10°44.967'N,
061°17.301'W, 104 m elev. (edge of rainforest over stream and in plantations and trails), 26 December (two 6-m,
one 9-m, one 18-m; 195 m-net-h; ARLI 1 [UNSM 29149], CAPE 15, GLSO 1, PHDI 2 [UNSM 29126, 29150],
PHHA 1, PTPA 3, STLI 2, STTI 1, URBI 2); (7) Asa Wright Nature Center, 10 o 42.98W, 061°17.895'W, 326 m
elev. (on trails in rainforest), 1 January (one 9-m, two 18-m; 112.5 m-net-h; ANGE 8 [UNSM 29161], ARGL 5,
ARJA 12, CAPE 23, CHTR 1 [UNSM 29160], CHVI 1, MIME 3, PHDI 2, PLHE 4, PTPA 2, SABI 2, STTI 1,
TRNI 1, URBI 4); (8) William Beebe Field Station, HQ, 10°41.515H 061°17.365'W, 198 m elev. (on trails and
small roads in second growth rainforest), 20 December (hand nets; SABI 1, SALE 1), 21 December (two 12-m
nets, one 9-m, one 2.6-m; 231.4 m-net-h; ARJA 1, ARLI 1, CHVI 3 [UNSM 29112, 29113], CAPE 13, GLSO 1,
MIME 1 [UNSM 29108], MYNI 1 [UNSM 29107], PLHE 2 [UNSM 29110], PTDA 1, SABI 1 [UNSM 29109],
URBI 3 [UNSM 29111]), 22 December (two 6-m, one 9-m, one 12-m; 181.5 m-net-h; ARGL 3 [UNSM 29099,
29100], ARJA 20, CAPE 16 [UNSM 29101], EPBR 1 [UNSM 29097], MIME 1, PHHA 2, PLHE 8, PTPA 2
[UNSM 29098], SALE 1 [UNSM 29096], URBI 22 [UNSM 29106]), 23 December (hand net; MOMO 1), 25
December (one 2.6-m, one 9-m; 69.6 m-net-h; CAPE 4 [UNSM 29151, 29152], SABI 1, URBI 3), 26 December
(one 6-m by roost in building; MOMO 46 [UNSM 29153]), 26 December (one 2.6-m, one 9-m; 17.4 m-net-h;
CAPE 4, GLSO 2 [UNSM 29154], MOMO 2, SABI 1), 30 & 31 December (two 6-m, two 18-m; 234 m-net-h
[=30 Dec., 4 h x 48 m-net and 31 Dec., 1.75 h x 24 m-net]; ARGL 1, ARJA35, CAPE 45 [UNSM 29147], CHVI

Geluso et al.—Bats in Northern Trinidad

13

1 [UNSM 29159], MIME 2, MOMO 1, PHHA2, STLI1, STTI1, TRNI1 [UNSM 29148], URBI12), 30 Decem¬
ber (hand net by building; MOMO 5); ( 9 ) near Aripo, 10°41.272'N, 061°13.318'W, 187 m elev. (edge of second
growth rainforest along stream and in small plantation), 24 December (two 9-m, one 18-m; 198 m-net-h; ANGE
3 [UNSM 29116, 29117], ARGL2, ARJA1 [UNSM 29119], CAPE 28, CHVI 5, MICR 1 [UNSM 29114], MIMI
1 [UNSM 29115], PHDI 1 [UNSM 29118], PHHA 1, PLHE 20 [UNSM 29125, 29132], STLI 2 [UNSM 29122,
29124], STTI 3 [UNSM 29120, 29121, 29123], URBI 5); and ( 10 ) near Guanapo River, Heights of Guanapo
Road, 10°40.566'N, 061° 15.364 1 'W, 177 m elev. (in trails in rainforest), 31 December (one 2.6-m, three 18-m;
254.7 m-net-h; ARGL 3, ARJA 18, ARLI 2 [UNSM 29157], CAPE 59, CHVI 1, GLSO 1, MIME 3, PHHA 4,
PLHE 10, THTR 1 [UNSM 29155], URBI 8 [UNSM 29158], VACA 1 [UNSM 29156]).

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