Nature on Trail: Fishers & Marten

By Sylvia Feder

A native Washingtonian, absent for almost a century, is on its way home. In January and March 2008, fishers were reintroduced to the Olympic Peninsula.

The story of the fisher’s disappearance from the state is a story of over-zealous trapping, destruction of old-growth forests and habitat fragmentation. The return of the fisher is a story of hope.

To understand the story, we first need to understand more about the fisher. Also known as Pennant’s cat, pekan and black fox, the names are as enigmatic as the fisher itself. Neither a cat, nor a fox, nor a water mammal, the fisher is actually a member of the weasel family, Mustelidae.

Its closest relative is the marten, a mustelid with whom it shares many traits. In a family that includes swimmers (otters, mink), diggers (badgers), and terrestrial mammals (weasels, skunks), marten and fishers are the only primarily arboreal members. They are so at home in the trees that they can outmaneuver squirrels, a favorite prey item.

The fisher is the larger of the two, weighing about as much as a cat (between about 5 and 10 lbs.); the marten rarely reaches 5 lbs. Both have weasel-thin bodies, short legs, fluffy tails, and rounded ears. Like many other mustelids worldwide, both marten and fisher have soft, thick, valuable fur (you may have heard the term “sable,” which refers to a close relative of the North American marten). 

Marten and fisher are opportunistic predators; in addition to squirrels, they will also eat small rodents, rabbits, an occasional fish and birds. Though primarily carnivorous, the marten may also nibble on berries and pine-cone seeds. The larger fisher is also one of the few predators that is able to tackle a porcupine, which it kills through repeated attacks to the unprotected face, neck and belly.

Both predators prefer dense, mature forests, and both are so at home in the trees and so fast that those who catch a glimpse are often left wondering what they have seen. Marten are found throughout the state in mountainous areas with mature forests; the populations are healthy enough that the state permits fur trapping in many areas.

Reproducing native populations of fishers, the other hand, probably disappeared from Washington in the early 1900s. At that time, fisher pelts were worth as much as $150 each, second only to that of the sea otter in value, and fishers were relatively easy to trap. Fisher populations decimated by trapping were further impacted by destruction of old growth forests and habitat fragmentation. Even though trapping of fishers was banned in the 1930s, the species never recovered. Although there have been occasional reports of fisher sightings over the years, for all practical purposes, the species is extinct in our state.

This may soon change. Last year, the Washington State Department of Fish and Wildlife released a recovery plan for the fisher in Washington, which calls for reintroducing as many as 100 fishers, over three years, to three areas of Olympic National Park: Elwha-Sol Duc, Hoh-Bogachiel, and Queets-Quinault. Careful study showed that these areas provided the best habitat for the initial repopulation effort.

It is not often that we have a chance to reverse a century of mismanagement and neglect. The fisher reintroduction plan provides hope that we can do just that—returning a missing predator to its ecosystem and providing those of us who enjoy wild areas a chance to glimpse a species that has been away for too long.

Finding Fishers and Marten

Winter is one of the better times to see marten. Unlike weasels, which turn white to match winter snow, martens keep their dark coats and can occasionally be seen scooting across the snow or pursuing squirrels from tree to tree. Marten prefer mature conifer forests and can be found throughout the state.

Wild fishers have recently been introduced to the Olympic Peninsula. Keep checking updates on the Olympic National Park Fisher Reintroduction web site for the status of the reintroduction effort. 

Photos: Young Marten on the Snow Lake Trail by Shane Farnor; release of a fisher in Olympic National Park by Paul Bannick, courtesy Washington Department of Fish & Wildlife.

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