Smithsonian National Museum of Natural History, North American Mammals
Search the Archive

  Rodentia · Erethizodontidae · Erethizon dorsatum
   Smithsonian Institution
   Copyright Notice
   Privacy Notice
Erethizon dorsatum

North American Porcupine

Order: Rodentia
Family: Erethizodontidae

Click to see adaptations.    Click to see a 3-D view.
Image of Erethizon dorsatum
Click to enlarge. (121 kb)

Conservation Status: Least Concern.

North American Porcupines are large, slow-moving, tree-climbing rodents, protected from predators by their formidable quills. In winter, they eat the bark, phloem, and cambium of trees, particularly conifers. In spring and summer, they mostly forage on the ground, feeding on grasses, sedges, acorns, and flowers. They readily consume crops or gnaw on automobile tires, so are sometimes regarded as pests. Porcupine young are exceptionally well developed at birth. Their eyes are open and they have teeth and even quills, which are soft at birth but harden within a few hours. Within a week, they can feed on their own. Few predators even try to kill Porcupines with any regularity, except one, the fisher. Fishers attack Porcupines from the front, grabbing them by the face, thus avoiding the quills. Porcupines do not throw their quills - which are modified hairs - but the quills pull loose from the Porcupine when they are stuck into an adversary, and they have barbed tips, so they are not easily removed.

Also known as:
Porc-epic, Hedgehog, Quillpig, Quiller

Sexual Dimorphism:
Males are heavier than females.

Average: 772 mm
Range: 600-1,300 mm

Range: 3.5-18 kg


Linnaeus, C., 1758.  Systema Naturae per regna tria naturae, secundum classis, ordines, genera, species cum characteribus, differentiis, synonymis, locis, p. 57.  Tenth Edition, Vol. 1. Laurentii Salvii, Stockholm, 824 pp.


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Erethizon dorsatum

Image of Erethizon dorsatum
Martes pennanti and Erethizon dorsatum - the fisher is one of the porcupine's few natural predators
Click to enlarge. (97kb)

Image of Erethizon dorsatum
Click to enlarge. (111kb)

Image of Erethizon dorsatum
Erethizon dorsatum (North American Porcupine), Adirondack Mountains
Click to enlarge. (87kb)

Image of Erethizon dorsatum
Click to enlarge. (120kb)

Bones and Teeth
Erethizon dorsatum
The sole of the right foot. Click to enlarge. (23kb)