Deer herbivory is widely recognized as a serious problem in forestry. Nevertheless, only few studies have touched upon the point of deer impact on woody plants in the transboundary areas of Lithuania and Belarus The attractiveness of habitats and adequate animal spatial distribution depend not only on food availability including links with the edge effect, disturbance and competition, but also on the availability of thermal and hiding cover. This occurs independently of the administrative borders between neighbouring countries. Habitat similarities of the neighbouring countries allow animals to migrate between the certain border territories using certain ecological (migration) corridors. Aiming to assess the impact of deer species on woody vegetation in the transboundary forests and the potential role of ecological corridors, I used the method that integrates sample plots (50 x 2 m) with the belt transects (100 x 4 m). I have determined simultaneously the main forest characteristics of each route unit and indices of the consumption of woody plants. The key species was Moose Alces alces L. The main limiting factors of moose impact on woody vegetation are the duration of non-vegetative period and its changeability that determines the time and extent of animal effect on woody vegetation throughout. During the prolonged wintry period, the clumped distribution of moose entails an increased effect on pine natural regeneration and plantations. In the short warm periods, moose concentrate in the pine plantations, alongside wet forest sites because of moose thermal sensitivity. The potential ecological corridors and their functional aspect for deer species have been revealed. The actual duration of the non-vegetative period should be considered.

Key words: transboundary area, moose, impact on forest, weather, ecological corridor