This is the last Monday Mustelid post of 2014 (don't worry - it shall continue). And it's a good one!
The American Marten (Martes americana), also called the American Pine Marten, can be found exclusively in the coniferous or mixed forests of North America. Their overall range extends from the northernmost treeline in Canada and Alaska, to the very top of northern Mexico. It was heavily hunted for its fur and extirpated from many parts of its historical range. Due to subsequent protection measures, they have been successfully reintroduced into some of those areas, but they are still hunted for their fur (though not to the same extent as they were during the 1800s).
American Martens resemble their larger relatives, the Fishers. They have an elongated body, rounded ears, and coats that range from a tawny yellow to dark brown, almost black. They will generally have some sort of bright marking on their chest, like a bib, that is yellow or orange. Males are generally longer and heavier than females, and can grow to 2.2 feet (67 cm) in body length, weighing about 3.1 pounds (1.4 kg). During the winter, they can lose heat easily due to their small reserves of body fat and scarcer food. To counter this, they will go into a shallow state of torpor each day to prevent excess loss of heat.
The primary prey of American Martens are voles, with adult Martens requiring about three voles per day to maintain their energy. They are also opportunistic, and will eat mice, birds, shrews, hares, squirrels, insects, and fruits and other vegetation. Intake of fruit is more common during the summer. The diversity in the diet of American Martens depends mostly on their habitat. Subarctic American Martens have the least amount of choice in their prey.
The breeding season of the American Marten typically occurs between July and August, and is generally the only time during which these solitary creatures will tolerate each other's company. Courtships can last up to 15 days, and the implantation of fertilized embryos is delayed until the winter, timed so that the kits are born in March or April. Active gestation lasts only for about a month. Females will give birth to one to five kits in a natal den, and may transfer them to a maternal den after their first few days of life. They will stay with their mother throughout their first summer, and will generally disperse during the autumn.
Deforestation and habitat degradation is one of the most significant threats to the American Marten today, and it is legal to trap a certain number of them each year in almost every state or province in which they live - this might account for up to 90% of the mortalities in a given area, especially around industrial forests. American Martens are also preyed upon by coyotes, raptors, foxes, owls, bobcats, and other predators.
Source for all images used in this post.