The Andros iguana (Cyclura cychlura cychlura) is the largest endemic terrestrial vertebrate species in the Bahamas. Yet, with less than 5,000 individuals estimated remaining in the wild, the Andros iguana is considered endangered under the International Union for Conservation of Nature (IUCN) Red List criteria and is listed under Appendix I of the Convention on International Trade of Endangered Species (CITES). The Andros iguana is threatened by multiple natural and anthropogenic factors, and enforcement of wildlife laws is lacking. Since 1999, scientists from the John G. Shedd Aquarium have been studying the biology and natural history of C. c. cychlura. Efforts have also been made to promote education and conservation of the species through outreach in local communities on Andros Island. In conjunction with the Bahamas National Trust, researchers hope ultimately, to establish a national park within the southern part of Andros Island for protection of the iguana and other native plant and animal species.
In March 2009, we initiated a veterinary component to the ongoing studies of C. c. cychlura. In conjunction with a long-term mark-recapture study, 35 sub-adult and adult iguanas (14 male, 21 female) were captured. Blood was collected within three minutes, and then each iguana was placed in a cloth bag for up to six hours. After a specified amount of elapsed time, a second blood sample, along with additional biologic data, was collected before releasing iguanas at the site of capture. The initial blood samples were used to determine reference intervals for blood gas, complete blood count (CBC), standard biochemical profile, plasma protein electrophoresis, vitamin D nutritional (i.e., vitamins A and E, beta-carotenes, trace minerals), and corticosterone (CORT) values. The second blood samples were used to determine iguana stress response to short-term confinement, via changes in the CORT and CBC values after various time intervals. Blood smears to establish CBC differentials were made with and without 22% bovine serum albumin to determine if the product increases the quality of cell preservation in this species. By partnering with field biologists and linking a veterinary medical component to an ecological study of the Andros iguana, we increase our ability to manage an endangered species effectively. We hope that this study is only the beginning of research into the conservation of the Andros iguana from a veterinary medical perspective.
The authors thank the member institutions of the Chicago Zoological and Aquatic Animal Residency Program for their support of this research. We would also like to thank the Brookfield Zoo for its support of this project through a Veterinary Education Research Grant, as well as Heska® Corporation for their generous support.