Differences in body sizes of mountain hares (Lepus timidus L., 1758) and moose (Alces alces (L., 1758)) affect their ability to perceive and respond to environmental heterogeneity and plant density. Therefore, we expect these species to show niche separation at different scales in the same environment. Results showed that the numbers of mountain birches (Betula pubescens subsp. czerepanovii L.) browsed by moose per unit area was inversely related to hare browsing. Moose browsed larger birches compared with hares, and while hares targeted areas with high birch densities regardless of tree sizes, moose preferentially browsed areas with high densities of large birches. Moose browsing was clustered at spatial intervals of 1000–1500 m, while hare browsing was clustered at intervals of less than 500 m. Willows (genus Salix L.) in the study area were heavily browsed by moose, while few observations of hare browsing on willow were made. Regarding both hare and moose, numbers of birch stems with new browsing per sample plot were positively correlated with the numbers of birch stems with old browsing, indicating that hare and moose preferred the same foraging sites from year to year. These findings have implications for management of the species because they show the importance of scale and landscape perspectives in planning and actions.
Cases of melanism in mountain hare (Lepus timidus) in Yakutia
