The diet of Bufo Bufo populations from central part of the Balkan peninsula and changes in the diet during ontogeny

Abstract

We analyzed the diet composition of Bufo bufo in the central part of Balkan Peninsula (Montenegro and Serbia) to define general diet preferences on southern and northern group of populations, by age categories and gender. We also addressed the potential correlation between Anurans body size by age category and prey size, and sex-based food niche partitioning in adults. Analysis revealed that Common Toads feed most frequently on insects, e.g., Coleoptera (Carabidae, Curculionidae) and Hymenoptera (Formicidae), but the taxonomic and numerical value of prey varies at the level of groups, sexes and by age categories. The results indicate that there is a positive correlation between the body size and the taxonomic and numerical value of the prey by age categories and gender in the populations of the southern group, while the statistical significance is lower in the populations of the northern group. Shannon-Vinner diversity index and the dominance index in the population of the southern group is (H=1.19: d=0.48), in the population of the northern group is (H=0.98: d=0.53). Although the analysis indicates diverse nutrition of the Bufo bufo species, there is a certain degree of specialization in certain parts of the region, so this species couldn’t be considered as a polyphagous predator. The results showed that Pianka niche overlapping index between the southern and northern groups is very high 95% (Qjk = 0.95), between males as much as 94% (Qjk = 0.95) among females as much as 97% (Qjk = 0.97), indicating that both groups use the same resources or sources of food.