Diet composition ofXenopus borealisin Taita Hills: effects of habitat and predator size

Abstract

Frogs in the genus Xenopus are ubiquitous in sub‐Saharan Africa, yet very little is recorded on their ecology. They are commonly found in anthropogenically disturbed habitats, but how do these compare to conspecifics from natural habitats? The diet of Xenopus borealis from three different sites in Taita Hills, Kenya was established based on a sample of 77 (54 females and 23 males) specimens from two disturbed and one pristine sites. Xenopus borealis from all the sites was found to be a dietary generalist, feeding predominantly on invertebrates. A total of twelve invertebrate orders both terrestrial and aquatic were recorded in addition to amphibian eggs, tadpoles and fish. Frogs from the pristine forest were smaller and had ingested more terrestrial prey items than frogs in the disturbed open habitat ponds. The stomach content (both by mass and quantity) was independent of body size. The results suggest that X. borealis is an opportunistic generalist predator which may be constrained by food availability in its natural habitat. However, disturbed habitats provide abundant food items which are enough to significantly increase the mean size of the population.

Competition and feeding ecology in two sympatric Xenopus species (Anura: Pipidae)

“…Within the genus Xenopus , these feeding modes have been attributed to the capture of different categories of prey, from benthic, planktonic, carrion, nektonic and terrestrial environments ( Measey, 1998b ; Lobos & Measey, 2002 ; Bolnick et al, 2003 ; Amaral & Rebelo, 2012 ). Despite the potential to consume diverse prey types, including carrion and other frogs ( Measey et al, 2015 ), most studies have revealed zooplankton and benthic invertebrates to constitute the major components of their diet ( Kazadi, Bruyn & Hulselmans, 1986 ; Schoonbee, Prinsloo & Nxiweni, 1992 ; De Bruyn, Kazadi & Hulselmans, 1996 ; Bwong & Measey, 2010 ).…”

Rainy Season Food Availability for Anurans of Kimboza Forest Reserve, Tanzania

“…Several studies (e.g. [25,26,27] Tohe et al, 2015) on the diet of anuran species belonging to genus Ptychadena, Leptopelis, Phrynobatrachus, and Xenopus established that these anurans are opportunistic generalist predators which lack feeding preferences and have a wide diversity of food groups with no constant food in their diets. These results to some extent support the study findings as species like Ptychadena anchietae, Phrynobatrachus natalensis Leptopelis flavomaculatus and Xenopus borealis had a wide diversity of food more than other anuran species in the forest, and no food group was constant.…”