Porcupine (Erethizon dorsatum)
Porcupines are gentle, misunderstood creatures who slowly, quietly wander our forests. When the lighting is right, a porcupine's yellow guard hairs give the illusion of a glow all around them. This slow moving animal's quills are their only defense.
Why They Matter to Us
- Keep forests healthy by eating mistletoe (a parasite of trees) and thinning out dense stands of saplings.
- Historically, First Nations people used porcupine quills to decorate clothing and other objects. Porcupines were also an important source of food.
How You Can Help
- Donate to help EALT protect important porcupine habitat.
- Volunteer to help EALT steward our natural areas and secure more areas to protect.
- Watch for porcupines on the road - they are slow moving and commonly get hit while crossing the road.
- Leave porcupettes alone - baby porcupines are left on the ground in a hiding spot during the day, while mom naps in the trees. She comes by at night to feed her young.
Porcupines cannot throw their quills. When danger threatens, the porcupine will hunch its back with all the quills standing up, and lash its tail threateningly when the predator or threat approaches. When the predator gets hit by the porcupine’s tail, the barbed quills stick in the predator’s skin and come out of the porcupine.
How to Identify
Identify by Sight
Porcupines have a dark brown face and undercoat with yellow-tipped guard hairs. These long guard hairs conceal the ~30,000 quills on their back and tail. The quills are approximately 1" to 2.5" long. They have short powerful legs, a thick tail, and long curved claws. Adult porcupines weigh around 22 lbs.
Identify by Sign
Look for bark stripped off of trees and willows, high off the ground. You can differentiate it from hare feeding by the height of the chew marks - if a hare couldn't reach that high, it was likely a porcupine. Also note, deer rubs leave behind stripped pieces still hanging on the tree, where as a porcupine eats the bark.
Where to Find
They are widespread in much of Canada, the United States and some parts of northern Mexico.
Their range includes habitats from northern forests to open tundra, rangelands, and deserts.
Because of their herbivorous habits, they're usually found in vegetated riparian habitats like mature forests along rivers.
- Porcupines are not very social and spend most of their time alone. However, they may share a den in the winter and sometimes forage for food in groups.
- Porcupines of both sexes defend their territories. They rarely venture out of their territory, although have been known to do so for salt or apple excursions.
- Porcupines climb trees to forage for food. In the summer they eat leaves of trees, shrubs, and forbs.
- In the winter they eat inner tree bark (cambium), buds, twigs, and evergreen needles.
- Sometimes they chew on leather, bones and shed antlers for salt, and to hone their incisors teeth, which can grow approximately 1.5 mm weekly.
- Porcupine's main predators are fishers and cougars, and are also sometimes preyed upon by wolves, coyotes, lynx, bobcats, wolverines, and great horned owls.
- Porcupine quills are hollow, reducing their weight, and also making them buoyant swimmers!
- Porcupine body temperature can drop 5 degrees C, when the ambient temperature falls near -18 degrees C, which is an adaptation to cold, and keeps them in the same position in trees for several days.
- Porcupines can live for up to 18 years in the wild!