The structure of vertebrate predator community in north-eastern Belarus before and after naturalization of the American mink and raccoon dog

Abstract

The structure of the vertebrate predator community in north-eastern Belarus has been examined before and after naturalization of the American mink and raccoon dog. Species composition of the community, population density and biomass, portion of each species in the pooled community density and biomass, species body mass and size structure of the community were investigated. The community consisted of 36 native predator species, and 11 other predator species were sporadically registered in the area in both periods before the American mink and raccoon dog expansion and after the introduced species have reached a high population density. Separating predator species into four size groups, we found that in terms of total density the largest portion of the community belonged to small predators, while large predators formed the smallest portion. In terms of total biomass, the larger medium-sized predator group predominated over other size groups. Despite decline in the populations of ten native predator species, the total community density and biomass as well as portions of different size groups appeared to be very similar before and after naturalization of the introduced predator species.