Winter habitat use and responses to snow cover of fisher (Martes pennanti) and marten (Martes americana) in southeastern Manitoba

Abstract

A trailing study of fisher (Martes pennanti) and marten (Martes americana) in the boreal forest of Manitoba, conducted over two winters, showed that both species preferred coniferous ridges. They also had temporal differences in their habitat use that could be partially explained by their different responses to soft snow cover. Movements of fisher were found to be restricted by the soft, thick snow cover that was present during midwinter. Fewer tracks were observed at that time, and fisher travelled upon snowshoe hare trails and their own trails more than in either the early winter period of thin snow cover or the late winter period of crust conditions. Fisher were also found to walk through the snow cover and leave a body drag in midwinter. Marten did not appear to be hindered by soft snow cover to the degree that fisher were. Marten tracks were encountered with equal frequency throughout the winter and marten never left a body drag in the snow cover. They did travel upon hare trails and their own trails to a greater extent in midwinter, but never as much as did fisher.