North American Porcupine


porcupine feb 18 2012 224

Photo by Ann Brokelman 

Species: North American Porcupine

Scientific Name: Erethizon dorsatum

Status: common

Description: The north american porcupine is famous for its quills and Canada’s second largest rodent (after the beaver).  These mammals have more than 30,000 quills, which are actually modified hairs. Quills are hollow, with a pointed at the tip and have some tiny barbs that help it embed into their predators skin. Quills are darker at the base  and become lighter, to a white hue, at the tip. Contrary to what most believe, porcupines are not able to “throw” their quills.  Instead, when attacked, they will lower their head (as most quills here are more hair like and not used for defense), and swing their tail at their attacker.  The quills will swell an expand once in the skin of the attacker which makes them even harder to extract. As with most mammalian species, the male is larger than the females. These rodents have small eyes, sharp claws on their front paws and short legs.

Habitat: Porcupines are found in a wide range of habitats including coniferous, mixed and deciduous forests. Porcupines do not hibernate during the winter, but will remain close to their dens, feeding during dry weather throughout both day and night. In the summer, they become more nocturnal, and will feed further from the den.

Breeding: Many people question how these prickly mammals are able to reproduce. Porcupines reach sexual maturity around 1.5 years of age. Mating season in Ontario is in late fall, where males will follow females around and serenade them with grunts and hums. Females are in heat, or sexually receptive, for a maximum of 12 hours and will be the ones to initiate courtship. Once ready to mate, the female will relax her quills, and moves her tail to the side to allow for the male to mount her. Females are pregnant for 30 weeks and babies, usually a single porcupette, are born between March and May.  Baby porcupines are born with soft quills, which harden a few hours after birth. These babies will nurse up to four months, but are able to start eating green vegetation within a few weeks of birth.

Diet: Porcupines are herbivores. They will eat buds, twigs and bark.  During spring and summer they enjoy catkins and elder leaves, poplar and willow. They will also eat currents, roses, dandelion, clovers and grasses. During the colder months, porcupines survive on the inner bark of trees. They prefer beech, white pine, and hemlock.

Threats to species: These large mammals do not move quickly.  Although their quills are a great defense against animal predators, their slow locomotion makes them vulnerable to strikes by vehicles. Additionally, some predators have learnt where to bite a porcupine without suffering any pain from the quills by biting their head or neck. Common predators of porcupines include lynx, coyote, red fox, bear and great horned owls.

Threat to humans: Porcupines pose no threat to humans, and are actually quite easy to walk up to due to their nearsightedness and slow moving.

Fun facts:

Porcupines have a very distinct odour to them. It smells like body odour. I like to describe it as a room full of pre-pubescent sweaty kids before they start using deodorant.

Porcupines crave salt, especially during the winter months, and will often be seen chewing on the glue of hydro poles along the side of highways.

Despite being quite arboreal (found in tree tops), porcupines are known to fall out of trees occasionally, breaking bones and even stabbing themselves with their own quills.

Porcupines sitting in trees are often mistaken for squirrel nests, or a crow.

Porcupines are known to chew on wood and leather around camps.


Eder, Tamara, and Kennedy, Gregory. 2011. Mammals of Canada. Lorne Pine Publishing. Edmonton, Alberta.

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