Natural History of West lndian Reptiles and Amphibians Robert W. Henderson and Robert Powell University Press of Florida :AINESVILLE .TALLAHASSEE .TAMPA . BOCA RATON . PENSACOLA .ORLANDO ' MIAMI .JACKSONVILLE . FT. MYERS . SARASOTA Copyright 2009 by Robert W. Henderson and Robert Powell Printed in the United States of America on acid-free paper All rights reserved 14t312 111009 654321 Library of Congress Cataloging-in-Publication Data Henderson, Robert W, 1945- Natural history of West Indian reptiles and amphibians / Robert W Henderson and Robert Powell. P.cm. Includes bibliographical references and index. ISBN 978-0-8130 -339 4-5 (alk. paper) 1. Reptiles-West Indies. 2. Amphibians-West Indies. I. Powell, Robert, 1948- II. Title. QL656.5.A1H46 2009 597.909729-dc22 2009017139 The University Press of Florida is the scholarly pubiishing agency for the State University System of Florida, comprising Florida A&M Universiry Florida Atlantic Universiry Florida Gulf Coast University, Florida International Universiry Florida State University, New College of Florida, University of Central Florida, University of Florida, University of North Florida, University of South Florida, and University of West Florida. University Press of Florida 15 Northwest 15th Street Gainesville, FL 32611-207 9 http://w.ww.upf.com Funding to assist in publication of this book was generously provided by the following organizations: The Falconwood Foundation through The Conservation Agency, Jamestown, Rhode Island The Herpetologists' League. 12 Family lguanidae Figure 15. Aggressive displays of competing male Cycluraiewlsi (lguanidae) may include gaping, lateral presentations, crest and dewlap erection, and elevation on allfour limbs. Such displays can escalate into actual combat if neither participant submits. Photograph by John F. Binns (lnternational Reptile Conservation Foundation)' Cyclura carinata Harlan, 1824 mosaic (Iverson, 1979). Behavior: Performs headbobs to declare territories, challenge males, and for sex recognition Distribution: Two historically recognized subspecies in (Iverson, 1979); most headbob displays consist ofa series oi the Turks and Caicos Islands (C. c. carinata) and Booby alternating single and double headbobs, each display usu- Cay (east of Mayaguana Island, Bahamas; C. c. bartschi), al- ally beginning with 1-2 single headbobs or a fast "trill" of though subspecific recognition of C. c. bartschi is not war- 6-15 bobs, followed by a set of 1-6 double headbobs, fol- ranted (Stephen, 2005, 2006; Bryan el al, 2007). lowed by single headbob or two, head nods and tail raises Habitat: Xerophilic (Schwartz and Henderson, 1991); 1o- typical of other iguanas also occur (Martins and Lamont. cally abundant on smaller islands with herbaceous to shrub 1998); aggressive displays include lateral orientation. gap- stage growth (Schwartz and Carey, 1977); on Booby Cay, ing, gular expansion, arched back, crest elevation, inflated iguanas on sandy and rocky beaches, rocky areas, sparsely trunk, lateral compression, and single or double headbobs. and densely vegetated areas, and open areas, used sandy aggression also may involve tail lashing and fighting (Car- areas and holes between rocks for burrows, in bushes and penter, 1982); will take to water as an escape tactic, but onlr' (Wasilewski, abundant trees to heights of 1.8 m 1998); most as a last resort (Iverson,1979). Diet: Primarily herbivorous in rocky coppice and sandy strand habitats, sandy areas are at all ages (95.6Vo of all food items and 94.8o/o of volume: required for nesting (Gerber and Iverson, 2000). Auffenberg, 1982); feeds both terrestrially and arboreallr-. Activity: Diurnal activity bimodal during warmer months, 600/o of macroplant species (including a few toxic forms (i high midday temperatures result in reduced activity, winter eaten, with plants taken falling into three categories: activity reduced and primarily at midday, basks following Common staples of high caloric content, (2) commor. emergence and prior to termination of day's activitl', rest staples of low caloric value (roughage), (3) foods eaten of day spent feeding, interacting with other lizards, and frequently in spite of their uncommonness (plants of hig: thermoregulating, which involves shuttling in sun/shade preference levels), certain individual plants are repeatedi'' 114 \- Family lguanidae . i15 browsed whereas others of the same species are ignored, populations on French, Six Hills East, Bay, and Middle cays caloric content in the form of nonstructural carbohydrates exhibit larger average adult sizes and reach maturity more is not an important factor in leaf and fruit choice, animal rapidly (1.5-2.5 years versus 6-7 years) than on source prey includes crabs (Clibanarius arrd Cardisoma), insects cays, Big Ambergris and Little Water (Gerber and Alberts, (termites, beetle larvae and adults, cicada nymph, dipteran 2005, 2006). Sex Ratio: l:1 at all age classes (Iverson, 1979). larvae), a slug, and carrion (fish, lizard, bird, rodent, and Size: Adult male SVL to 360 mm, female SVL to 292 mm canned meats, especially sardines), during the winter, re- (Schwartz and Henderson, l99l). Survivorship and Life stricted to items that are more difficult to digest (leaves), Expectancy: Survivorship positively correlated with body rvhich may pass through the digestive tract almost intact size, life expectancy 14.0 years (Iverson, 1979).TailAutot- (Iverson, 1982); cannibalism (Iverson, 1979; Aufenberg, omyz32.60/o of males and28.60/o of females on Pine Cayhad 1982); one well-developed circular valve and 4 more dis- broken tails (Iverson, 1979). tal semilunar valves partition the proximal colon (N 15), = Conservation Status: The species is listed in CITES Ap- presumably to increase digestive efficiency (Iverson, 1980); pendix I (UNEP-WCMC, 2008); 'tritically endangered" on truits of Turk's Cap Cactus (Melocactus azureus; S6nchez the IUCN Red List (Gerber, 1996a,2004b;Gerber and West Mufloz, 2008). Home Range and Territoriality: Adult Indian Iguana Specialist Group, 2000); both C. c. carinata males are territorial throughout the year (Gerber and Iver- and C. c. bartschi as "threatened" on the U.S. List of En- son, 2000); average home range 980 m2 in females, 1,260 dangered and Threatened Wildlife and Plants (U.S. Fish & m2 in males, 1,590 m'zin dominant males (Iverson, 1979). Wildlife Service, 2008) primarily due to predation by in- Parasites: Nematodes (Alaeuris travassosi, Ozolaimus troduced mammals (dogs and cats), competition with and monhystera, Paralaeuris cyclurae; Dosse, 1939); very large degradation ofhabitat by introduced herbivores (e.g., cattle oxyurid nematode (Cyrtosomum mega) populations in co- and goats), habitat alteration by human activity, and exploi- Ion, perhaps mutualistic rather than parasitic (Bowie and tation by humans; a conservation and management plan Fratz, 1974); to >15,000 presumably commensal or even exists (Burton and Bloxom, 2007a); domestic dogs and cats mutualistic nematodes in a healthy adult (Iverson,l9B2). reduced the population (estimated 5,500 animals) on pine Physiological Demands: Glucocorticoids (used to evalu- Cay almost to extirpation in 3 years following construction ate heightened physiological demands under varying con- of a hotel and tourist facility (Iverson, 1978). ditions) significantly greater in female C. c. carinata than in males, tended to be inversely related to body condition in females but not in males, in |anuary, somewhat higher Cycl u ra col I ei Gr ay, 1845 in the morning, affected by reproductive state and possibly Distribution: )amaica, Hellshire Hills (extirpated elsewhere by seasonal rainfall (MacDonald et al., 2007). Population on the island, including Goat and Little Goat islands). Density: Estimated densities along flush transects on pine Habitat: Xerophilic, tropical dry forest in low limestone Cay 1.7 -3 6.8 adults/ha ( Iverson, 197 B) ; 9 0.3 I ha in optimum habitat for juveniles, 31.1/ha for adults (Iverson, 1979);558 hills along shores and in areas between the coast and in- terior uplands, iguanas in 14.5/ha on Booby Cay, Mayaguana (Conners et in hollow trees in pastures, where congre- gated (Schwartz and Henderson, 1991); retreat a1., 2005, 2006). Population Sizes: Estimated 50,000 C. c. site fidelity ;arinata and 1,000 C. c. bartschi (Alberts, 2004); estimated is strong, with hatchlings preferring dead hollow trees 6-15 30,000 C. c. carinata and 200-300 C. c. bartschi (Hudson cm in diameter with a northwesterly aspect (Van Veen and and Alberts, 2004). Predators: Feral dogs and cats (Iver- Wilson, 2004, 2005);17 of 155 observations of headstarted son, 1978, 1979; Mitchell et al., 2002; Mitchell, 2003; Ger- iguanas released into the wild were in trees to heights of -7 m (D. S. Lewis et )er and Alberts, 2005,2006). Reproduction: Cycles are a1.,2008). with climatic 'r'nchronized cycles, courtship in early May, Behavior: Will climb, can climb a smooth fence post (C. B. :robably serial polygyny with monogyny among some Lewis, 1944); headbob displays consist ofa single headbob nales, eggs 2-glclltch in early |une, females defend bur- or three single headbobs with pauses of 0.7-1.0 sec between :ows for several days to several weeks after nesting, but are them (Martins and Lamont, 1998). Foraging and Diet: :rot territorial at other times, hatching occurs after approxi- Leaves, fruits, and flowers of a wide variety of plant spe- nately 90 days, hatchlin gs averuge79.8 mm SVL and 14.6 g, cies, supplemented occasionally by animal matter, includ- 'uvenile growth rate averaged 19.2mmSVL/yr, males reach ing snails (P. Vogel,2000a); of 25 types of plants consumed, sexual maturity at approximately 220 mm SVL, 375-475 g, 3-4 species of vines are most important (Van Veen and rge about 7 years, females 185-200 mm, 200-300 g, 6-7 Wilson, 2004,2005); foraging in tree canopies (D. S. Lewis ;ears (Iverson, 1979); individuals in recently established et al., 2008). Home Range and Territoriality: 0.59-5.82 ha 116 ' Part ll. Reptilia, Section 1. Squamata (lizards) for 6 repatriated iguanas, home ranges overlapped consid- xeric lowlands), also Isla Beata, ile-de-la-Petite GonAve, erably, probably reflecting recency of release (D.