Porcupine

Identification

Porcupines (Erethizon dorsatum), sometimes called “porkies” or “quill pigs,” are heavy-bodied,
short-legged, slow, and awkward rodents, with a waddling gait. Adults are typically 25 to 30 inches
(64 to 76 cm) long and weigh 10 to 30 pounds (4.5 to 13.5 kg). They rely on their sharp, barbed
quills (up to 30,000 per individual) for defense.
Food Habits

Porcupines eat herbaceous plants, inner tree bark, twigs, and leaves, with an apparent preference
for ponderosa pine, aspen, willow, and cottonwood. Trees with thin, smooth bark are preferred over
those with thick, rough bark. Porcupine feeding is frequently evident and has considerable impact on
the cottonwood stands of western river bottoms.
General Biology, Reproduction, and Behavior

Porcupines breed in autumn, and after a 7-month gestation period usually produce 1 offspring in
spring. Although the young are capable of eating vegetation within a week after birth, they generally
stay with the female through the summer. Juvenile survival rates are high.

Predators of porcupines include coyotes, bobcats, mountain lions, black bears, fishers, martens,
great horned owls, and others. Coyote scats (feces) containing large numbers of quills are not
unusual. How the quills are maneuvered through the coyote’s gastrointestinal tract is a mystery.

Porcupines are active year-round and are primarily nocturnal, often resting in trees during the day.
They favor caves, rock slides, and thick timber downfalls for shelter.

Damage and Damage Identification

Clipped twigs on fresh snow, tracks, and gnawings on trees are useful means of damage
identification. Trees are often deformed from partial girdling. Porcupines clip twigs and branches that
fall to the ground or onto snow and often provide food for deer and other mammals. The considerable
secondary effects of their feeding come from exposing the tree sapwood to attack by disease,
insects, and birds. This exposure is important to many species of wildlife because diseased or
hollow trees provide shelter and nest sites.

Porcupines occasionally will cause considerable losses by damaging fruits, sweet corn, alfalfa, and
small grains. They chew on hand tools and other wood objects while seeking salt. They destroy
siding on cabins when seeking plywood resins.

Porcupines offer a considerable threat to dogs, which never seem to learn to avoid them. Domestic
stock occasionally will nuzzle a porcupine and may be fatally injured if quills are not removed
promptly.

Economics of Damage and Control

Economic losses can be considerable from porcupines feeding on forest plantings, ornamentals,
and orchards as well as on leather and other human implements. Porcupines generally are tolerated
except when commercial timber, high-value ornamental plantings, orchards, or nursery plants are
damaged by girdling, basal gnawing, or branch clipping. On occasion, porcupines thin dense,
crowded forest stands. Often tree diameter growth is reduced. Their preference for mistletoe as a
food is an asset.

The porcupine is acclaimed as a beautiful creature of nature. It is an interesting animal that has an
important place in the environment. It is edible and has been used by humans as an emergency
food. The quills are used for decorations, especially by Native Americans. The hair, currently used
for fly-fishing lures, commands many dollars per ounce. Porcupines are not wary and can be readily
observed and photographed by nature lovers. Porcupines may need to be controlled but should not
be totally eradicated. The Oklahoma Wildlife Control® , LLC., is a nuisance & predatory wildlife
solutions and service company, with a number of specialties. However, OWC is not an animal
rescue organization. If you have problems with domestic cats and dogs, we suggest that you
contact your local animal shelter for assistance. Thank you.