The analysis of food spectrum of a lake frog (rana ridibunda) in the urbanization territory of the Middle Volga region

A food of lake frog Rana ridibunda, Pallas, 1771 was investigated in the sites with a variable degree of an urbanization conditions, in districts mainly with low-storeyed buildings, in a forest park zone, in a residential suburb and in the control. The greatest trophic niche width, according the Sλ index was noted in control conditions (Sλ = 17,28), residential suburb (Sλ = 16,58), in a forest park zone (Sλ = 16,38) and the least (Sλ = 11,53) in the conditions of sites with low-storeyed buildings.