DIETARY CONSTITUENTS OF Ptychadena SPECIES FROM A MONOCULTURE PLANTATION AND A RAINFOREST HABITAT IN SOUTHERN NIGERIA

Abstract

The dietary constituents of 72 specimens of Ptychadena spp. (P. mascareniensis, P. longirostris, P. bibroni, P. pumilio and P. oxyrhynchus), collected from a monoculture plantation (Oil Palm) and a natural rainforest environment were investigated. A total of 87 prey items comprising of 12 taxa were recorded from the stomachs of the frogs examined. More prey item taxa were recorded in the forest frogs than from the altered environment of the monoculture plantation. Lepidoptera (10.34%), Mollusca (5.75%), Diptera (2.30%), Isopoda (3.45%), Blatteria (2.30%), Annelida (1.15%), Myriapoda (2.30%) and Anura (1.15%) were only recorded in frogs from the rainforest while Hymenoptera (26.44%) was recorded only in anurans collected at the Oil Palm plantation. Orthoptera (16.09%), Coleoptera (19.54%) and Araneae (9.20%) were common to both habitats. There was significant difference in the rate of feeding activity of frogs collected from both study locations (p<0.05). The prey item diversity recorded in the stomachs of the Ptychdena species examined suffices their classification as generalist feeders, with an active foraging behaviour. The finding of a juvenile frog in the stomach of P. mascareniensis is an indication of cannibalism, which hitherto was unknown among the Ptychadenidae in Nigeria