Cyclura Pinguis) Is a Critically Endangered Species Endemic to the Puerto Rico Bank and Currently Restrictedprofile to the British Virgin Islands (BVI)
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WWW.IRCF.ORG/REPTILESANDAMPHIBIANSJOURNALTABLE OF CONTENTS IRCF REPTILES & AMPHIBIANS IRCF REPTILES • VOL15, & N AMPHIBIANSO 4 • DEC 2008 189• 20(3):112–118 • SEP 2013 IRCF REPTILES & AMPHIBIANS CONSERVATION AND NATURAL HISTORY TABLE OF CONTENTS FEATURE ARTICLES Vertical. Chasing Bullsnakes structure (Pituophis catenifer sayi) in Wisconsin: use by the Stout Iguana On the Road to Understanding the Ecology and Conservation of the Midwest’s Giant Serpent ...................... Joshua M. Kapfer 190 . The Shared History of Treeboas (Corallus grenadensis) and Humans on Grenada: (CycluraA Hypothetical Excursion pinguis ............................................................................................................................) on Guana Island,Robert W. Henderson BVI198 RESEARCH ARTICLES Christopher. TheA. TexasCheek Horned1, Shay Lizard Hlavatyin Central and1, KristaWestern TexasMougey .......................1, Rebecca Emily Henry, N. Perkins Jason Brewer,1, MarkKrista Mougey, A. Peyton and Gad 1Perry, Caitlin 204 N. Ryan2, . The Knight Anole (Anolis equestrisJennifer) in Florida C. Zavaleta 1, Clint W. Boal3, and Gad Perry1 .............................................Brian J. Camposano, Kenneth L. Krysko, Kevin M. Enge, Ellen M. Donlan, and Michael Granatosky 212 1Department of Natural Resources Management, Box 42125, Texas Tech University, Lubbock, Texas 79409 2The Institute of EnvironmentalCONSERVATION and Human ALERT Health, Department of Environmental Toxicology, Box 41163, Texas Tech University, Lubbock, Texas 79409 3U.S.. GeologicalWorld’s Mammals Survey, in CrisisTexas ............................................................................................................................................................. Cooperative Fish and Wildlife Research Unit, Texas Tech University, Lubbock, Texas 220 79409 . More Than Mammals ...................................................................................................................................................................... 223 . The “Dow Jones Index” of Biodiversity ........................................................................................................................................... 225 HUSBANDRY . Captive Care of the Central Netted Dragon ....................................................................................................... Shannon Plummer 226 Abstract.—The Stout Iguana (Cyclura pinguis) is a critically endangered species endemic to the Puerto Rico Bank and currently restrictedPROFILE to the British Virgin Islands (BVI). Our study on Guana Island, BVI, focused on vertical structure use. Based on previous. Kraig Adler: incidental A Lifetime Promoting observations, Herpetology ................................................................................................ we hypothesized that Stout Iguanas Michael use L.vertical Treglia 234structures and that adults and juvenilesCOMMENTARY use such structures differently. In October 2011, we documented movement and vertical structure use by adult (n =. 4)The Turtlesand juvenileHave Been Watching (n = 11)Me ........................................................................................................................ iguanas with tracking bobbins. We recorded Ericstructure Gangloff 238 types used, heights attained on structures,BOOK REVIEW distances between structures, and structure sizes. We found that Stout Iguanas used vertical structure more than. Threatened previously Amphibians documented. of the World edited Trees by S.N. comprised Stuart, M. Hoffmann, a significantly J.S. Chanson, greaterN.A. Cox, (P < 0.001) proportion of struc- tures used by juvenilesR. Berridge, than P.by Ramani, adults, and B.E. whereas Young .............................................................................................................. rocks comprised the greatest proportion of Robert structures Powell 243 used by adults. In addition to differential structure use, juveniles climbed significantly higher (2.4 vs. 0.9 m on average; P < 0.001) than CONSERVATION RESEARCH REPORTS: Summaries of Published Conservation Research Reports ................................. 245 adults. We found NATURAL no difference HISTORY in RESEARCH the diameter REPORTS or distance: Summaries between of Published Reportsstructures on Natural used History by ................................. adults and juveniles. 247 Our results suggest that vertical NEWBRIEFS structure ...................................................................................................................................................................................... use may be an important habitat element for free-ranging juvenile Stout 248 Iguanas. Habitat EDITORIAL INFORMATION ..................................................................................................................................................... 251 management that FOCUS provides ON CONSERVATION vertical structure: A Project may You be Can advantageous Support ............................................................................................... for the conservation of this species. 252 he Stout Iguana (Cyclura pinguis; Fig. 1) is endemic to 1990s. While a headstarting program continues on Anegada, the Puerto Rico Bank and has been listed as critically eight iguanas were introduced to privately owned Guana T Front Cover. Shannon Plummer. Back Cover. Michael Kern endangered (Mitchell 1996, USFWSTotat et1999). velleseque Whenaudant mo Stout IslandTotat et(Fig. velleseque 3) audantin 1984 mo in an effort to conserve the species Iguanas were first described in 1917,estibus the inveliquospecies velique was restrictedrerchil (Goodyearestibus inveliquo and velique Lazell rerchil 1994). Guana Island is dedicated to erspienimus, quos accullabo. Ilibus erspienimus, quos accullabo. Ilibus to the flat and sandy island of Anegadaaut dolor (British apicto invereVirgin pe dolum Islands, tourismaut dolor apicto and invere has pe become dolum a de facto nature preserve. Anegada, BVI; Fig. 2). The common name “Anegadafugiatis maionsequat Iguana” eumque is also in whichfugiatis is maionsequat inhabited eumque by about 200 people, has more anthropo- moditia erere nonsedis ma sectiatur moditia erere nonsedis ma sectia- frequent use, despite subfossil evidencema derrovitae found voluptam, in caves as quos and in genictur ma disturbance derrovitae voluptam, than as Guana. Guana also differs dramati- middens that indicates the species onceaccullabo. inhabited much or all cally from Anegada in its volcanic origins, steep topography of the Puerto Rico Bank (Pregill and Olson 1981, Stephen (highest elevation 245 m), and a more complex vegetative 2012). The reduced distribution of Stout Iguanas was likely community (Lazell 2005). The difference in geology, soils, due to the habitat loss caused by rising sea levels and the and vegetation initially led to concerns that the iguana intro- introduction of non-native herbivores and direct predation duction would fail. However, the introduced population has by humans (Pregill and Olson 1981, Lazell 2005). done extremely well on Guana (Perry and Mitchell 2003, Anegada is flat (highest elevation < 10 m), highly sandy, Perry et al. 2007) and has since served as the source for several and the eastern two-thirds of the island consist of mostly subsequent introductions to other islands in the BVI (Perry exposed limestone rubble (D’Arcy 1975). Introduced preda- and Gerber 2011). tors, competition with non-native mammalian herbivores, Guana Island offers a multitude of vertical structures and habitat loss have all contributed to an extensive decline such as trees, vines, and large boulders (Fig. 4) that are mostly of the Stout Iguana population on the island (Mitchell 1999, absent on Anegada (Fig. 5). Use of habitat elements not cur- Bradley and Gerber 2005, Perry and Gerber 2011). Mitchell rently available on Anegada could partially explain the popu- (1999) estimated only 164 individuals persisted into the early lation decline of Stout Iguanas there and the observed popu- Copyright © 2013. Christopher A. Cheek. All rights reserved. 112 CHEEK ET AL. IRCF REPTILES & AMPHIBIANS • 20(3):112–118 • SEP 2013 Fig. 1. Adult Stout Iguana (Cyclura pinguis). Photograph by Doug Bell. Fig. 2. Aerial photograph of Anegada Island. Photograph by Krista Mougey. 113 CHEEK ET AL. IRCF REPTILES & AMPHIBIANS • 20(3):112–118 • SEP 2013 Fig. 3. Aerial photograph of Guana Island. Photograph by Krista Mougey. lation growth on Guana. We therefore focused our study on piles], rock [boulders, and rock piles], and cement structures), two questions: (1) What types of vertical structures do igua- and the diameter at breast height (DBH) of trees used. nas use on Guana, and (2) how do juveniles and adults use these structures differently? Materials and Methods We tracked adult and juvenile Stout Iguanas that had been captured by hand and fitted with thread bobbins (Wilson 1994) for up to four days. Bobbins (200 m of string) were placed inside a balloon that had been coated with a rubber spray to form a rigid exterior (Performix© Plasti-Dip). The coated balloons were then glued anterior to the base of the tail on each iguana. The device weighed less than 5% of animal mass. We released iguanas at capture sites within 24 hours and attached the end of the bobbin string to a fixed object. Upon release, juvenile iguanas usually only ran 1–2 m. Adults tended to flee farther after release and often went straight to a burrow,