Quick Answer
Sort them by size, color, and range. A fisher is the big one — 5 to 13 pounds, a foot and a half of dark, almost black-brown body with a thick bushy tail about a third of its length, and small rounded ears set low on the head. An American marten is much smaller, 1 to 3 pounds, lighter brown with a noticeably paler grayish face and often a creamy chest patch, with larger ears. And range does half the work: fishers are found statewide in Vermont and New Hampshire, while martens live only in the deep northern forests — Vermont's Northeast Kingdom and New Hampshire's North Country.
Fisher and Marten: Two Confused Forest Mustelids
New England's woods hold two similar long-bodied, dark-furred members of the weasel family that people routinely mix up — the fisher (Pekania pennanti) and the American marten (Martes americana). Both are slender, low-slung predators with short legs and thick winter fur. The Vermont Fish and Wildlife Department (VTFWD), the New Hampshire Fish and Game Department (NHFG), and the University of Vermont (UVM) Extension all field questions about which one crossed the trail, denned in the woodpile, or turned up at the edge of the yard at dusk.
Getting it right matters more than curiosity. Fishers are bold, roam widely, and are the ones that occasionally take poultry or a small outdoor cat. Martens are secretive, mostly stay in mature forest, and almost never come to houses. If you saw the animal near a backyard bird feeder, it was far more likely a fisher — a marten sighting that far from deep woods is rare.
Quick Comparison Table
| Feature | Fisher | American Marten |
|---|---|---|
| Adult weight | 5–13 lbs (males much larger) | 1–3 lbs |
| Head-body length | 13–19 in. | 13–18 in. |
| Tail | Thick, bushy, ~1/3 of total length | Bushy but shorter and lighter |
| Overall color | Dark chocolate-brown to almost black, darker on legs and tail | Medium chocolate-brown; lighter on the underside |
| Face / chest | Dark face; may show a small whitish chest patch | Paler grayish face; often a creamy orange chest patch |
| Ears | Small, rounded, set low and wide | Larger, more pointed and prominent |
| Habitat | Mixed and conifer forest, farmland edges, even suburban woodlots | Mature spruce-fir and mixed northern forest with deep snow |
| Range in New England | Statewide in VT and NH | VT Northeast Kingdom; NH North Country; rare south of the northern counties |
The Fisher: The Big, Bold Forest Predator
Fishers are the largest member of the weasel family in New England after the river otter, and the biggest difference you'll notice is weight — a big male fisher can top 12 pounds, while even a large marten rarely passes 3. An adult fisher is about a foot and a half of head and body with a thick, bushy tail that makes up another third of its length. The coat is dark chocolate-brown to almost black, darkest on the legs, feet, and tail, and it stays that color year-round — fishers never turn white in winter.
Fishers are powerful and wide-ranging. They roam forested areas but also travel farmland edges, ridgelines, and suburban woodlots, sometimes crossing yards at dusk or dawn. They are famous for being one of the few animals that regularly kills porcupines — flipping them over to attack the unquilled belly — and they also take squirrels, snowshoe hares, rodents, and birds. They climb well and, unusually, can descend a tree head-first thanks to rotating hind ankles.
Fishers den in hollow trees, rock piles, and abandoned burrows, and they use the same brushy cover that attracts your yard's mice and voles. If you see a large, dark, cat-sized animal with a long body and bushy tail slipping through the woods edge, it is almost certainly a fisher.
The American Marten: The Smaller, Paler Forest Cousin
American martens are the fisher's smaller, lighter-built cousin. An adult is only 1 to 3 pounds — roughly the size of a house cat but much longer and lower to the ground, with a tail that looks shorter and lighter than a fisher's. The fur is a medium chocolate-brown, paler on the belly, and the most useful field mark is the head: martens have a distinctly paler, grayish-brown face and often a creamy orange patch on the chest and throat, with larger, more pointed ears than a fisher's small rounded ones.
Martens are creatures of mature northern forest. They favor spruce-fir and mixed hardwood-conifer stands with deep winter snow, downed logs, and hollow trees, and they are superb climbers that hunt red squirrels, voles, mice, birds, and berries both on the ground and in the canopy. In New England, that habitat narrows the marten's range to Vermont's Northeast Kingdom — the species was reintroduced there in the 1980s and 1990s after being extirpated — and to New Hampshire's North Country around the White Mountains. See a marten south of those forests and you are almost certainly looking at a small female fisher or a large long-tailed weasel instead.
Winter Coats: Neither One Turns White
Unlike the smaller weasels — the long-tailed weasel and the ermine — neither fishers nor martens turn white in winter. Both keep their brown coats year-round, though they grow longer, thicker winter fur that can make a fisher look even darker and a marten look fluffier. So if you see a white weasel-shaped animal in the snow, it is an ermine or a long-tailed weasel, never a fisher or marten. For reading winter trail lines and separating mustelid runs from other snow tracks, see our Animal Tracks in Snow Identification Guide.
Tracks and Sign in Yards and Woods
Both species walk with the same loping, two-by-two bounding gait as all weasels, and their tracks look like larger, 5-toed versions of the weasel pattern — about 2 inches wide and long for a fisher, closer to 1½ inches for a marten. In deep snow, a fisher's trail often shows a subtle furrow where the body drags, and fishers use snowmobile trails and logging roads as travel routes, which is why they turn up in trail cams more than martens do.
Scat is another clue. Fisher scat is large, dark, and thick — up to an inch across — often packed with porcupine quills, fur, or bones, and fishers leave it conspicuously on trails, logs, and stumps. Marten scat is smaller and more twisted, with a musky scent, and martens use latrine sites near den trees. If you find a big, quill-studded dropping on a trail, a fisher made it.
FAQ: Fisher vs Marten
What is the main difference between a fisher and a marten?
Size is the fastest split. Fishers weigh 5 to 13 pounds and are dark, almost black-brown, with a thick bushy tail and small rounded ears. Martens weigh 1 to 3 pounds and are lighter brown with a paler grayish face, a creamy chest patch, and larger ears. Range helps too: fishers are statewide in Vermont and New Hampshire; martens are confined to the deep northern forests.
Are fishers bigger than martens?
Yes, considerably. A large male fisher can weigh four times a large marten. Both have similar body lengths, but the fisher is far heavier, stockier, and darker, with a noticeably thicker tail.
Do fishers and martens both live in Vermont and New Hampshire?
Fishers live statewide in both states. American martens are far more restricted: in Vermont they are found mainly in the Northeast Kingdom (the species was reintroduced there in the 1980s–90s after being extirpated), and in New Hampshire mainly in the North Country around the White Mountains.
Which one is more likely to be near my house or take my chickens?
The fisher. Fishers roam widely and will take poultry and occasionally a small outdoor cat, and they regularly pass through suburban woodlots and yards. Martens are secretive forest animals that almost never come to houses and rarely bother poultry. If something took a chicken or a small pet, suspect a fisher — and secure the coop with hardware cloth.
Are fishers and martens protected in Vermont and New Hampshire?
Both are furbearer species managed by VTFWD and NHFG, with defined seasons and trapping license requirements — fishers have a regulated trapping season, and marten seasons are strictly limited or closed. You may not trap or take them outside those rules. For damage from animals you can manage directly on your property, contact your county UVM Extension office or NHFG first.
What should I do if I see one in my yard?
Enjoy it from a distance — both species prey on the rodents that damage gardens and neither is aggressive toward people. Keep small pets inside at dusk and dawn, secure poultry with hardware cloth, and remove easy cover like stacked wood next to foundations. A fisher passing through a yard once is normal; repeated visits usually mean a food source such as unsecured pet food or an active bird-feeder rat problem. For the other mustelids people confuse with these two, see our Mink vs Weasel vs Ermine Guide.
Sources: Vermont Fish and Wildlife Department (VTFWD), New Hampshire Fish and Game Department (NHFG), University of Vermont (UVM) Extension, USDA Forest Service mustelid references. This guide is for informational purposes only and does not constitute professional wildlife management advice.