Dissertation/Thesis Abstract

An analysis of the demography and habitat usage of Roatán's spiny-tailed iguana, Ctenosaura oedirhina
by Campbell, Ashley B., Ph.D., Florida Atlantic University, 2015, 111; 10154936
Abstract (Summary)

The Roatán Spiny-tailed Iguana (Ctenosaura oedirhina ) is endemic to the 146-km2 island of Roatán, Honduras. Harvesting for consumption, fragmentation of habitat, and predation by domestic animals threaten this lizard. It is currently listed as Endangered by the International Union for Conservation of Nature (IUCN), as threatened by the Honduran government, and is on Appendix II of the Convention on International Trade in Endangered Species (CITES). This species has been geographically fragmented and genetically isolated into small subpopulations that are declining in density. With data gathered from use/availability surveys, resource selection functions were used to identify habitats and environmental variables associated with their presence. Results indicate that protection from harvesting is the most important factor in determining their distribution. These high-density populations are currently restricted to ∼0.6 km2. Organisms living in small, isolated populations with very restricted ranges are at higher risk of extirpation due

to various direct and indirect forces. Mark-recapture-resight surveys and distance sampling have been used to monitor the populations since 2010 and 2012 respectively. The data show that the high-density populations are declining. The current population size is estimated to be 4130-4860 individuals in 2015. A population viability analysis (PVA) was conducted to identify the most pressing threats and specific life history traits that are affecting this decline. The analysis estimates that if current trends persist, the species will be extinct in the wild in less than ten years. Adult mortality is a main factor and female mortality specifically characterizes this decline. In order for this species to persist over the next fifty years, adult mortality needs to be reduced by more than 50%. A lack of enforcement of the current laws results in the persistence of the main threat, poaching for consumption, thus altering the species distribution and causing high adult mortality. This is complicated by social customs and a lack of post primary education. Management changes could mitigate this threat and slow the population decline. Recommendations include an education campaign on the island, increased enforcement of the current laws, and breeding of C. oedirhina in situ and ex situ for release into the wild.

Indexing (document details)
Advisor: Maple, Terry, Gawlik, Dale
Commitee:
School: Florida Atlantic University
School Location: United States -- Florida
Source: DAI-B 78/01(E), Dissertation Abstracts International
Source Type: DISSERTATION
Subjects: Wildlife Conservation, Ecology, Conservation, Caribbean Studies
Keywords: Ctenosaura oedirhina, Endemic, Habitat usage, Hunting pressure, Population monitoring, Population viability analysis
Publication Number: 10154936
ISBN: 9781369100211
Copyright © 2019 ProQuest LLC. All rights reserved. Terms and Conditions Privacy Policy Cookie Policy
ProQuest