Creature Feature: The American Marten
The American Marten is a rare North Woods animal that you'll probably never see, save for paw prints in the snow. This brown, bushy-tailed little critter, which looks something like a cross between a mink and a house-cat, was prized for its luxurious fur and darn near trapped to extinction in the United States during the 19th century. (The Hudson Bay Company alone was killing 180,000 martens a year in the 1850s.)
Today, despite habitat loss or fragmentation and related problems, the American Marten still inhabits much of its historical range. It’s a good thing, too. Nature designed this interesting little predator to exploit its woodland niche in an exquisitely efficient manner. Its lifestyle is in tune with its habitat, supports the intricate web of forest life, and adds a worthwhile element of diversity. It won’t attack your child, kill your livestock, or eat your pet. It just thrills you to the marrow if you are lucky enough to see it in its wilderness world.
The American Marten (Martes americana) is a member of the weasel family and has the slender, elongated body, prominent ears, pointy face, and luxuriant fur that is the weasel family’s trademark. Confusion attends the fact that the American Marten is called the pine marten in some quarters (because it resembles a European cousin of that name), looks a lot like the even smaller stone marten (a recent Eurasian import), and has a western variant that might well be a distinct subspecies. It can also be mistaken for an immature fisher (Martes pennanti), a bigger and darker-furred member of the weasel family that lives in the same habitat and has similar tracks.
That said, knowledgeable observers don’t find it inordinately difficult to recognize the American Marten.
Females are seldom more than three-quarters as large, but a big male American Marten will be 20 or so inches long and weigh around 2 ½ pounds (a good ten pounds less than a big male fisher). Its big eyes, large pointed ears, and other facial features make the marten look somewhat like a bushy tailed house-cat. And like a house-cat, this lithe, quick, and curious animal has sharp teeth, good claws, and marvelous hunting skills.
It does the cat one better by being able to pursue squirrels through the treetops and, if necessary, jump to the ground unhurt from high branches. This little critter does most of its hunting on the forest floor, however, and is not very particular about what it will eat. Its dietary staples are mice, voles, shrews, frogs, fruit, small birds, rabbits, insects, and other small prey, but a hungry marten will eat just about anything it can catch or find. It will even eat carrion if live prey is scarce. Martens do most of their foraging at night, which is a big reason why people see them so seldom during the day.
Martens are wilderness and backcountry animals that prefer dense old-growth coniferous or mixed deciduous forests that have some cavities in the trees and plenty of fallen logs, coarse woody debris, and dead foliage on the forest floor. The debris and decaying matter play an important part in martens' lives, since it harbors the prey that they prefer.
If you ever get the chance to track a marten in the snow, you will see that this little hunter stays busy, busy, busy, and keeps moving, moving, moving. Thanks to big furry paws that distribute its weight, the marten can run atop the snow instead of sinking into it.
A marten’s thick glossy fur, which can range from dark brown to buff, insulates it from the bitterly cold winters of its high latitude or high elevation forest home. American martens don't hibernate. Instead, they patrol their territories looking for prey. Tunneling beneath the snow to catch mice is one of the main ways they get winter food.
American Martens can still be found in many places with suitable habitat throughout the northern states, in some cold subalpine forests, and in the Canadian taiga as far north as the Arctic fringes. There are isolated populations living in the Adirondacks, Rockies, Sierras, Cascades, and northern Pacific Coastal Ranges as well as the deep woods of northern Michigan, Wisconsin and Minnesota. Quite a few national parks have American Marten populations, including Voyageurs, Rocky Mountain, Yellowstone, Grand Teton, Glacier, Yosemite, Crater Lake, and North Cascades.
The American Marten isn’t truly abundant in any of these places. Like many other wilderness hunters, this little predator needs its space. For all their apparent lushness, the boreal and subalpine forests actually have a low net primary productivity – a fancy way of saying that food is not plentiful for predators like the marten.
Depending on the quality of the habit and other factors, an individual marten may require from one to three square miles of forest to eke out a living. The marten is a predominantly solitary hunter. Males and females will tolerate each other’s presence, though both will defend their territory from other martens of the same sex. Reminiscent of river otters, martens occasionally enjoy playing with other martens - but only during the mating season. Sounds that wildlife biologists call huffing and chuckling are some of the animal's favorite social vocalizations.
The mating season starts in June and continues through the summer. One to five marten kits are born blind and helpless in March or April. They mature quickly, and at four months the young martens are able to leave the den and fend for themselves. A marten that is tough enough and fortunate enough may live as long as 17 years.
What the future holds in store for the American marten is an interesting question, since the answer depends heavily on habitat quality and human stewardship. Martens need large areas of pristine or only lightly developed forest and tend to retreat as land development advances. Thus, while marten populations have remained reasonably stable in protected areas and the more remote northern areas of the animal’s range, numbers have declined substantially in the Great Lakes states and western mountains – that is, in the places most impacted by deforestation, habitat fragmentation, livestock grazing, and recreational activities or other human use the forest.
Marten recovery programs, though constrained by habitat availability, can mitigate losses to some degree. The programs are designed to establish or bolster populations in areas that have at least marginally suitable habitat. Wisconsin's marten recovery program is one example. Starting in 1953, the state of Wisconsin began returning American Martens into areas that lacked them or had breeding populations too small to ensure healthy genetic diversity. In partnership with the U.S. Forest Service, Wisconsin wildlife authorities released 172 martens into the Chequamegon-Nicolet National Forest. Current estimates place the marten population there at 100-150 animals, and another 100 are scheduled to be released before the year is out. The Great Lakes Fish and Wildlife Commission continues to monitor marten populations via radio telemetry, and the University Wisconsin at Stevens Point is studying the animals as well.
The Canadians are also helping martens. The Newfoundland subspecies is considered endangered, and in 1999 the Newfoundland/Labrador government announced a land-preservation effort aimed specifically at improving the martens’ habitat. "[Our] Government is committed to the preservation and protection of Newfoundland and Labrador's outstanding and unique natural heritage,” said Charles Furey, Minister of Tourism, Culture and Recreation. “The Little Grand Lake initiative announced [on October 15, 1999] is essential to ensure preservation of the marten, which is an indigenous endangered species. The provisional ecological reserve, in particular, will protect the habitat required for a core population of marten considered essential for the continued viability of this species in Newfoundland. This is also extremely significant because for the first time ever government has established a reserve to protect three indigenous eco-regions.”
The American Marten doesn't have widespread American federal protection, but it is on several state endangered species lists. Marten protection is a contentious issue in some states. In Colorado, for example, an internal memo leaked to the press in 2001 revealed that the Colorado Division of Wildlife was considering allowing marten trapping. This revelation angered many local animal protection groups, considering that, “In a June 14 2001 report, a CDOW biologist acknowledged that "marten populations have never been rigorously studied in Colorado”
Also in Colorado, the U.S. Forest Service authored a “Species Assessment” for the American Marten, citing logging, disease, insect infestations, and fire suppression as possible future problems for the species.
Jim Woodford, a wildlife biologist for the Wisconsin Department of Natural Resources has expressed concern that global warming could have a big impact on the marten population. “The marten does better during years of high snowfalls in the north,” he said, “When there is less snowfall, like we have seen in the last few years, they are at a disadvantage.”
If you love the woods and wild things, I hope you will soon get the chance to be where martens live. And if you happen to see one, give it plenty of space, savor the moment, and take a photograph. Be sure to report sightings to land managers or wildlife officials. Wildlife biologists are eager to determine current population levels and can use all the help they can get.