Search Field Guide
Advanced Search
Montana Animal Field Guide

Montana Field Guides

Porcupine - Erethizon dorsatum

Google for more images Google for web pages

Global Rank: G5
State Rank: S4

Agency Status
USFWS: none
USFS: none
BLM: none
CFWCS Tier: 3





 

General Description
Common porcupine adults in the Northwest average 30 inches long and 20 pounds in weight. Round, short-legged, and slow in movement, they are protected by a coat of quills that covers all but their underside and the insides of their legs. Up to 30,000 of these modified hairs, yellowish white and black- or brown-tipped, mix with coarse guard hairs, and lay over thick, brownish underfur. The hollow quill shafts may be up to 5 inches in length and the guard hairs twice as long. They concentrate on the rump and short tail. The porcupine sheds this coat yearly. Long, heavy claws enable the porcupine to climb and curl up in trees. Its excellent hearing and sense of smell make up for poor vision (Foresman 2001). At night the porcupine's bright eyes appear red. Its grunts and high-pitched cries can be heard from a distance of (Burt & Grossenheider 1964). Newborns are born with teeth, eyes open, and soft quills that harden within an hour. They can climb the same day.

General Distribution
Montana Range



Western Hemisphere Range

 


Summary of Observations Submitted for Montana
Number of Observations: 336

(Click on the following maps and charts to see full sized version) Map Help and Descriptions
Relative Density

Recency

 

(Records associated with a range of dates are excluded from time charts)



Migration
Non-migratory. However, in mountainous areas seasonal alti- tudinal migration may occur.

Habitat
Common in montane forests of Western Montana, also occurs in brushy badlands, sagebrush semi-desert and alon streams and rivers (Hoffmann and Pattie 1968). Rockfall caves, ledge caves, hollow trees, or brushpiles for dens (Dodge 1982).

Food Habits
In winter uses cambium, phloem, & foliage of woody shrubs & trees--Ponderosa Pine, Lodgepole Pine, perhaps spruce & fir. In spring & summer uses reprod. parts & foliage of aspen, forbs, grasses, sedges & succulent wetland vegetation (Dodge 1982)

Ecology
Has a tendency to return to familiar areas/trees. Predators include man, fisher, marten, mink, wolverine, mountain lion, lynx, and bobcat. Solitary most of year, but may den com- munally in winter.

Reproductive Characteristics
May be polyestrous. Parturition occurs in late April or early May, some births as late as August. Pups can eat solid food within a week, but generally remain with female throughout the summer (Dodge 1982).

Citations & Sources
  • Burt, W. H. and R. P. Grossenheider. 1964. A field guide to the mammals. 2nd edition. The Peterson Field Guide Series. Houghton Mifflin Co., Boston, MA.
  • Foresman, K.R. 2001. The wild mammals of Montana. Special Publication No. 12. American Society of Mammalogists
  • Kritzman, Ellen B. 1977. Little mammals of the Pacific Northwest. Pacific Search Press, Seattle, WA.
  • Zeveloff, S. I. 1988. Mammals of the Intermountain West. Univ. of Utah Press, Salt Lake City, Utah.
Login Logout
Citation for data on this website:
Porcupine — Erethizon dorsatum.  Montana Field Guide.  Retrieved on February 9, 2010, from http://FieldGuide.mt.gov/detail_AMAFJ01010.aspx
 
There are currently 58 active users in the Montana Field Guide.