Status of a Translocated Cyclura Iguana Colony in the Bahamas

Abstract

A cross-sectional population biology study was performed on a translocated Allen's Cay iguana (Cyclura cychlura inornata) colony 10 years postintroduction. Between 1988 and 1990, eight iguanas (4d, 4$) were translocated to 1.8-ha Alligator Cay in the Exuma Island chain, Bahamas. Of the original eight translocated iguanas, seven were recaptured. Twenty-eight descendants were captured; 39% male, 57% female, and 4% juveniles. An estimated minimum population size of 62 individuals was calculated using a revised Petersen mark-and-recapture method and flush transect data. Nine descendant age classes were represented in the capture data or via visual observation. Descendant iguanas demonstrated a significantly higher average annual growth rate for both males and females (35.3 and 30.1 mm, respectively) than iguanas from the founder population (17.6 and 11.4 mm, respectively). The two most observed plants (34.8%) in scat samples included the leaves, buds, and stems of Rhachicallis americana and Suriana maritima. Rhachicallis was more prevalent (19.8%) than Suriana (15.0%) in scat samples. However, Rhachicallis was more abundant on the island and the Electivity Index indicates that it was a slightly less preferred food item than Suriana (-0.02 and 0.50, respectively). Alligator Cay possesses numerous vegetative and topographic characteristics, which are ideal for iguana habitation and population growth, and contributed to the successful translocation. Conservation initiatives involving translocation programs should be considered a sagacious method if proper precautions are undertaken prior to iguana release.