Diet and habitat preferences of the Fijian Crested Iguana (Brachylophus vitiensis) on Yadua Taba: implications for conservation
The Fijian Crested Iguana Brachylophus vitiensis is restricted to tropical dry forest habitat and has been extirpated from over 80% of its original range due primarily to habitat destruction. A large population on Yadua Taba island has been proposed as a source for iguana translocations. This study aimed to determine the dietary and habitat requirements of the herbivorous B. vitiensis on Yadua Taba to identify essential tree species. The diet of B. vitiensis was studied using faecal analyses while perch preferences were examined using field surveys. Four surveys were carried out between September 2005 and June 2006. Faecal analyses on 233 iguanas identified 26 plant species in B. vitiensis diet while field surveys recorded 1425 iguanas in 33 tree species. The most common diet species were Vavaea amicorum, Diospyros elliptica, Micromelum minutum, Jasminum didymum and Hibiscus tiliaceus which largely overlapped with the most common perch species V. amicorum, D. elliptica, Mallotus tilifolius, H. tiliaceus, Kingiodendrum platycarpum and M. minutum. There were no major seasonal shifts, gender differences or age class variations in diet. We found no gender differences nor seasonal shifts in perch tree species, however there was a difference in perch preference between adults and juveniles. These results suggest that while B. vitiensis occurs in and consumes a number of plant species on Yadua Taba, it is primarily dependent on only a few species. Future translocations of B. vitiensis need to ensure that these important tree species are present in new sites to vastly improve translocation success.