What Eats Porcupines? The Fisher and Other Predators

The fisher: the porcupine specialist

The fisher (Pekania pennanti) is a dark-brown, long-bodied mustelid of northern forests, related to martens and wolverines. Males weigh about 3.5–6 kg (8–13 lb) and females about 2–2.5 kg (4–6 lb), so a big male is roughly half the weight of an adult porcupine. Despite its name, it rarely eats fish. Its main prey are snowshoe hares and porcupines.

The fisher’s method avoids the quills. A porcupine’s face, throat and belly have no quills, so the fisher circles the porcupine on the ground and darts in to bite its face, again and again. The porcupine turns to keep its back and tail toward the attacker, but the agile fisher keeps getting around it. Observations describe attacks lasting roughly 25–30 minutes before the porcupine is exhausted and dies.

Fishers then roll the porcupine over and feed from the unprotected underside. Because males are much bigger than females, researchers think large males are the main porcupine hunters. Fishers still collect some quills, but they seem to suffer few lasting problems.

Fishers and forests

Fishers were trapped out of much of the northern United States by the early 1900s. Without them, porcupine numbers rose in some regions, and so did bark damage to timber. In the mid-20th century, several states and provinces released fishers, partly to restore this natural check. Where fishers returned, porcupine numbers often fell back to more typical levels.

Cougars, bobcats and lynx

The cougar (mountain lion) is the other major predator. Cougars do not try to avoid every quill. They knock porcupines from trees or flip them on the ground, and some cougars have been found with dozens of quills in their gums without obvious harm. In parts of the Great Basin, cougar predation has sharply reduced porcupine numbers in mountain forests. Our cougar profile covers this big cat in detail.

Smaller wild cats take porcupines too. Bobcats kill them in some areas, and Canada lynx take them occasionally. For these cats, a porcupine is a risky meal that is usually attempted only by experienced hunters or when other prey is scarce.

Coyotes, wolves and wolverines

Wild dogs kill some porcupines, especially in winter when a porcupine walking across open snow is easier to reach. Coyotes and gray wolves are both recorded as predators. However, many canids end up with quills in the muzzle rather than a meal, and canids are generally considered a minor threat.

The wolverine, a powerful relative of the fisher, also eats porcupines where the two overlap in northern forests and mountains.

Bears and birds of prey

American black bears sometimes kill porcupines, though they are opportunists rather than porcupine specialists, and a bear that tries may be left with quills in its lips and paws. Porcupines are only a small, occasional item in a bear’s mostly plant-based diet.

Only two birds are known to prey on North American porcupines: the great horned owl and the golden eagle. Both are large, powerful hunters, and they most likely take young porcupines, called porcupettes, or catch adults by surprise.

Table: porcupine predators at a glance

How porcupines defend themselves

Porcupines rely on warnings first. They give off a strong smell, chatter their teeth and raise their black-and-white quills. If that fails, they turn their back, keep their head tucked and lash out with the quill-covered tail. In trees they climb high onto thin branches where heavier predators cannot follow. Learn more in Can porcupines shoot their quills?.

This defense works against most attackers. Predators that have been quilled once usually avoid porcupines afterward, and some die from embedded quills or infections. That is why only a few animals, above all the fisher, hunt porcupines regularly.

Other dangers for porcupines

Predators are not the only threat. Many porcupines die from starvation in late winter, falls from trees and, increasingly, collisions with vehicles, since road salt draws them to roadsides. People have also hunted porcupines in the past; some states once paid bounties for them because of tree damage. See our full North American porcupine profile for its life cycle and conservation status.