The European pine marten (Martes martes) takes its name from its habitat, living mostly in woodland and preferring to spend most of its time in pine trees. A member of the stoat and weasel family, it is mainly active at dusk and during the night. A fast treetop hunter and very agile, it is the only mustelids with semi-retractable claws, which enables it to climb trees as well as run on the ground.