Peculiarities of nutrition of the lake frog (Pelophylax ridibundus Pallas, 1771) in the urbanized territory of the city of Belgorod (Russia)

It is known that urban landscapes often experience abrupt changes in environmental conditions, which can have a negative impact on the viability of the populations that live here. This in turn causes a reduction in biodiversity in general. One of the most effective methods of analyzing the degree of ecosystem degradation is the study the trophic relationships of animals. Of particular interest in this regard are tailless amphibians, in particular green frogs, which are tolerant to anthropogenic pressures, and are often used as bioindicators. One such species is the marsh frog (Pelophylax ridibundus). This species has a high ecological plasticity and often inhabits both anthropogenically modified and natural landscapes. This paper presents data on food preferences of the marsh frog in conditions of urbanized areas of Belgorod. Based on the study of 46 stomachs, it was revealed that the most preferred food objects are representatives of the orders of Hymenoptera, in 43 % of stomachs, Diptera, in 32,6 %, Coleoptera, in 30 % and also larvae of various insects in 28 %. In addition, representatives of Hemiptera, Gastropoda, Lumbricina, Odonata, Oniscidea, Dermaptera, Ephemeroptera were present in the stomachs. It is worth noting that despite the presence of different-aged individuals in the studied population, no traces of cannibalism were found. The data indicate a good food base of the studied species, despite the anthropogenic transformation of coastal biotops.