Sidorovich, V.E., Polozov, A.G. & Solovej, I.A. 2008: Niche separation between the weasel Mustela nivalis and the stoat M. erminea in Belarus. - Wildl. Biol. 14: 199-210.
We investigated three main niche components (diet composition, habitat use and diel activity rhythms) to examine how the weasel Mustela nivalis and the stoat M. erminea, both specialised predators of small rodents, could permanently coexist in Belarus. Our research was carried out in temperate forests of Belarus, in two study areas with different environmental conditions: 1) continuous dry-land forest interspersed by a variety of swampy biotopes and aquatic ecosystems (Paazerre, northern Belarus) and 2) extended wetland with large forest patches (Palesse, southern Belarus). The habitat use and diel activity rhythms of seven weasels and eight stoats were analysed by radio-tracking over about 300 km2 in Paazerre. Snow-tracking was also applied to study habitat use by the two mustelid species. Diet composition was examined by analysing 365 weasel scats and 606 stoat scats. Our results suggest that while the weasel and stoat occur in close proximity to each other, they use different micro-habitats, are most active during different times of the day, and prey primarily on different small rodent species. Most weasels selected forest and forest edge habitats, where they predominantly preyed on smaller rodent species (bank voles Clethrionomys glareolus and Apodemus mice); stoats selected wetlands, especially open grassy marshes, and preyed more frequently on larger rodents such as water voles Arvicola terrestris and Microtus voles. Weasels were mostly diurnal and adjusted their activity to the seasonally
changing length of daylight, whereas stoats were much more active in twilight and during the night.
Key words: Belarus, diel activity rhythm, diet, habitat selection, stoat, weasel
Vadim E. Sidorovich, Alexey G. Polozov&Irina A. Solovej, The Vertebrate Predation Research Group, Institute of Zoology, National Academy of Sciences of Belarus, Akademicheskaya Str. 27, 220072 Minsk, Belarus - e-mail addresses: vadimsid@mustbel.open.by (Vadim E. Sidorovich, Alexey G. Polozov & Irina A. Solovej)
Corresponding author: Vadim E. Sidorovich
Received 26 June 2006, accepted 17 January 2007
Associate Editor: Piero Genovesi