Natural history and morphometry of the Cuban iguana (Cyclura nubila Gray, 1831) in Cayo Sijú, Cuba

Abstract

The report presents data about the Cuban iguana population (Cyclura nubila nubila) inhabiting Cayo Sijú, an 88 ha island off the southwest coast of Cuba. Population densities estimated using strip transects were higher in xerophytic coastal scrub (6.72 ± 6.25 iguanas/ha) than in typical sand vegetation (3.63 ± 2.71 iguanas/ha) and mangrove forests (2.9 ± 2.9 iguanas/ha). The total population for the cay was estimated at 350 individuals with an adult biomass of approximately 11.67 kg/ha. Densities varied minimally between three habitat types and between the wet and dry seasons. No significant density fluctuations were found one month after Hurricane Ivan affected the cay. Iguana burrows were encountered most frequently in beach dunes. Analysis of 30 scat samples revealed eight species of plants, with the fruits of Chrysobalanum icaco and the leaves of Batis maritima being the most frequently identified items. The remains of crab (Cardisoma guandhumi) and insects of the order Hemiptera were also present in scat samples. Sexual dimorphism was evident in this population, with males being significantly larger in eight morphological variables. The snout-vent length measurements were larger in this population than in those reported in two cays off the south coast of Cuba.