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North American Porcupine

Erethizon dorsatum

Northamericanporcupine Gallery

About the North American Porcupine


Geographic Range:


Class: Mammalia  
Order: Rodentia
Family: Erethizontidae
Genus: Erethizon   
Species: dorsatum 

The North American porcupine has a thick underfur covered with long, wiry guard hairs on the front of its body. There are up to 30,000 shorter, heavier quills on its back, sides, legs, and tail. When threatened, the porcupine doesn’t “shoot” its quills. It sheds them upon impact so the quills imbed in their attacker. The name porcupine is derived from a French word meaning “thorny hog.”

Porcupine Facts

Porcupines have thick underfur covered with long, wiry guard hairs on the front half of their body. They have up to 30,000 shorter, heavier quills on their back, sides, legs and tail. They may have yellowish quills and yellow-tipped guard hairs, or white quills and white-tipped guard hairs. Porcupines have long, curved claws, causing them to walk pigeon-toed on the ground. Their broad feet and sharp claws help them dig for roots and for shelter. They have unique, bright- orange incisors like those of beavers.

Length: 2.5 to 3.5 feet
Weight: Up to 28 pounds

Porcupines may eat up to a pound of plant material per day, and they gnaw on old bones and shed antlers for calcium and salt. They feed on the inner bark of trees and evergreen needles during the winter. Porcupines eat buds in the spring, roots, leaves berries, fruits and seeds in the summer, and fruits and nuts in the fall.

Generally, single offspring are born in the spring after a gestation of about seven months. Young are capable of feeding on plant material by 2 to 3 weeks of age and are weaned by late summer. They reach maturity by 2 to 2.5 years of age.

Porcupines are mainly nocturnal, but they may be seen during the day, especially in the tops of trees. They climb awkwardly, but they’re more at home in trees than on the ground. Generally, porcupines are solitary in the summer and colonial in winter, living in dens. Dens are found in hollow trees or natural caves in rocks. Foulsmelling urine marks their territories. They do not hibernate.

They communicate with grunts and high-pitched cries that may be heard for a quarter of a mile, especially in the fall rutting season. Acute hearing allows them to respond quickly to threats.

Porcupines don’t "shoot" their quills; they rattle and shed them upon impact so they become imbedded in an attacker. Quills also provide buoyancy while swimming.

Widely distributed throughout Canada, northern Mexico and the United States; they are absent from southeastern United States.

Median Life Expectancy:
Up to 10 years in the wild.

Threats in the wild:
Bobcats, cougars, coyotes, fishers, and wolverines prey on porcupines. Fishers are particularly adept at attacking porcupines by flipping them to expose their vulnerable abdomen. Porcupines are also killed by humans as “pests” because they can damage ornamental plants, wooden buildings, tool handles and other wooden objects.

Fun Fact:
The porcupine’s common name is derived from French and means “thorny hog,” referring to the animal's quills. The scientific name, Erethizon, is Greek for "arouse" and is a reference to the species' reputation for being irritable. Dorsatum, is Latin for back.