Prey Availability or Electivity in the Diet of some Amphibians from Olinlin- Uzea, Esan North East, Edo State, Nigeria
The diet of four species of frogs, Hoplobatrachus occipitalis, Ptychadena bibroni, Amietophrynus maculatus and Leptopelis sp. from Olinlin -Uzea, Esan North East Local Government Area in Edo State, Nigeria was studied between July and November 2014. Specimens were stomach-flushed and a total of 166 prey items from 13 prey categories recorded. Hoplobatrachus occipitalis had the highest niche breadth (6.04) indicating a rich diversity of prey while Leptopelis sp. an arboreal frog had the least (2.67). Hoplobatrachus occipitalis and P. bibroni had a niche overlap of 0.79 indicating a common use of the microhabitat while no overlap was recorded between Leptopelis sp. and Amietophrynus maculatus and P. bibroni. The low electivity indices observed in Hoplobatrachus occipitalis, Ptychadena bibroni, and Amietophrynus maculatus is an indication that feeding was based more on the availability of prey rather than preference. Although a high electivity index was recorded for Leptopelis sp, it is most likely due to its restricted microhabitat and the corresponding available prey. Caution should, however, be employed with electivity indices as results could be affected by inadequate sampling.