Diet of amphibians and reptiles from the Engare Ondare River Region of central Kenya, during the dry season

In seasonally and environments many species undergo some form of dormancy, such as aestivation. The dietary habits of those species during the period of seasonal aridity are poorly known. Little is known of the seasonal variation in the diet of the amphibians and reptiles of Kenya. This project examines the diets of several species of frogs and lizards collected during the dry season in an and part of central Kenya. Some of the species were thought to be dormant during that season and others were thought to be actively feeding. The incidence of feeding may be used to determine if an animal is dormant. The dormancy may be brief and interrupted or protracted and continuous. Stomach contents were removed by dissection and analyzed in the laboratory. We identified 6,238 prey items to the lowest taxonomic unit possible, usually order, family, or genus. Definite prey items were all Arthropoda except for a single frog in one stomach and skink scales in a few stomachs. Within Arthropoda, Isoptera and Hymenoptera (ants) were the most abundant (5,662 items), followed by Coleoptera and Orthoptera (205 items). Eruciform and scarabaeiform larvae were recorded separately from adults. At least ten other orders of arthropods were recovered. Spiders were present in 12.4% of the stomachs. Specialization was exhibited by some species that utilized termites or ants extensively. A few nematodes were found. Inanimate objects were also found, including miscellaneous plant material, rocks, and charcoal. Termites were more important in reptile diets than in amphibian diets and were used almost exclusively by ground dwelling lizards. Termite specialists contained 87% or more termites and ant specialists contained 72% or more ants. Ptychadena anchitae and P. maseareniensis were the only generalists, based on a Shannon Diversity Index of > 0.75. Active and reproductive species had a significantly higher number of food events than active and non-reproductive species. All of the species examined were secondary, or partially tertiary, consumers and the prey taxa were mostly primary consumers, but included several secondary consumers. Reproductive species and non-reproductive species in the same genus had different diets and preferences.