43 % of Slovakia is forested. Species of fir and spruce are common in most mountain areas. At lower elevations, oaks, birches, and lindens predominate. Slovakia’s forests are home to foxes, rabbits, squirrels, weasels, and muskrats; wild boar and wolves are occasionally seen in remote mountain areas. Wildlife stocks have been diminishing in Slovakia, due to pollution, urbanization, and deforestation.