Porcupines
Porcupines are nocturnal mammals belonging to the order Rodentia, primarily classified under the families Erethizontidae and Hystricidae. Found across various regions, North American porcupines inhabit forests and wooded areas, while South American species thrive in tropical rainforests, with other varieties present in Africa and Asia. These animals are known for their distinctive quills, which are modified hairs that serve as a formidable defense mechanism against predators; they do not throw their quills but instead allow them to penetrate through contact.
Porcupines primarily feed on a herbivorous diet consisting of tree bark and other plant materials, and they exhibit solitary behavior except during the breeding season. Notably, the gestational period varies by species, and typically only one young, called a porcupette, is born, fully equipped with open eyes and quills. Their lifespan can range from ten to fifteen years in the wild, and they have a significant size variation, with weights ranging from 2 to over 40 pounds, depending on the species. While some porcupine species are not at risk, others face vulnerabilities due to environmental changes. Overall, porcupines are remarkable creatures that adapt well to their surroundings, showcasing unique behaviors and adaptations in their life cycle.
Porcupines
Porcupine Facts
Classification:
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Erethizontidae and Hystricidae
Genus and species: Various
Geographical location: North American porcupines are found throughout Canada, extending into the northeastern and western United States; South American porcupines live in the tropical rain forests of South and Central America; various other porcupine species live in Africa and Asia
Habitat: Ranges from tropical rain forests to deserts; some inhabit coniferous and deciduous forests, while others live in grasslands
Gestational period: Depends on species but can range from around 70 to over 200 for the North American porcupine
Lifespan: Ten to fifteen years in the wild, ten to twenty years in captivity
Special anatomy: Quills
Agile and armed, although they may seem slow, a porcupine is quick to make its point with its defensive quills. Porcupines do not throw or cast their quills into a potential predator; instead, quills penetrate a predator’s body on contact with the porcupine’s prickly body. The more than thirty thousand quills on a porcupine’s back and sides are actually modified hairs (one of the characteristics of mammals). Other common names for porcupines are quillpig and pricklepig.
North American porcupines are arboreal or semiarboreal, spending much of their day climbing trees and consuming tree bark. These herbivores ingest a variety of plant materials, from buds to roots. On occasion, porcupines may eat shed antlers of deer or elk for the various minerals, such as calcium, that they contain. Other species of porcupine are herbivores as well. Porcupines must watch out for predators, such as fishers, coyotes, bobcats, and owls.
Second in size only to the beavers in the class Rodentia, adult porcupines' weight varies by species. The bahia hairy dwarf porcupine weights only 2 pounds (0.9 kilograms), while the North American porcupine can grow to over 40 pounds (18 kilograms). The length attained by adults also varies drastically with species. While color variations occur, most individuals have dark-colored pelage. Porcupines are mostly nocturnal, but they may be observed during the day either on the ground or in trees.
Porcupine Life Cycle
Adult porcupines are solitary mammals for most of the year, except during the breeding season, between September and December. Female porcupines begin reproductive activities at about one and a half years of age. It is common to find several males around a female during her brief (eight- to twelve-hour) time of receptivity. Mating is brief and occurs on the ground, with the female raising her tail over her back. After the male has inseminated her, each porcupine goes its separate way.
Usually, only one porcupette, as the young are sometimes called, is born after a gestation period that varies with species. Weighing between four hundred and five hundred grams at birth, newborn porcupines are quite precocial. Their eyes are open, and their quills are present, as are their incisors and premolar teeth. Although capable of consuming vegetation within a week of birth, the young are nursed by their mother through the summer months.
Porcupines consume the inner bark of trees and shrubs, especially in the fall and winter, when the plants on the ground are becoming dormant or dying. It is easy to observe porcupine feeding sites in the forests by observing the limbs and trunks of trees. If the outer bark has been stripped away, the whitish-colored areas beneath are quite apparent. During the spring and early summer, porcupines spend more time on the ground, feeding on tender shoots and buds of emerging plants.
While their vision is not acute, their olfactory (smell) and auditory (hearing) senses are well-developed. Some researchers have reported observing porcupines standing up on their hind legs and sniffing their surroundings. If a porcupine detects a potential predator, it will form a defensive posture of lowered head and back, at the same time raising the tail for swinging. The heavy, muscular tail can drive quills deep into a predator’s face and head.
While some species of porcupine are not threatened, others are considered vulnerable species.
Principal Terms
Arboreal: living in or spending time in trees
Dorsal: the back portion of an animal
Herbivore: an animal that consumes vegetation for its diet
Notochord: a dorsal, flexible, rodlike structure extending the length of a vertebrate’s body; serves as an axis for muscle attachment
Pelage: a mammal’s fur coat
Predator: any animal that preys on another animal
Quills: sometimes referred to as spines, modified guard hairs; quills have barbed tips which can work themselves deeper into flesh once they have penetrated
Bibliography
Buchsbaum, Ralph, et al. The Audubon Society Encyclopedia of Animal Life. New York: Crown, 1982.
Chapman, J. A., and G. A. Feldhamer, editors. Wild Mammals of North America: Biology, Management, and Economics. Baltimore: The Johns Hopkins University Press, 1982.
Feldhamer, G. A., L. C. Drickamer, S. H. Vessey, and J. F. Merritt. Mammalogy: Adaptation, Diversity, and Ecology. Boston: WCB/McGraw-Hill, 1999.
Manning, Elizabeth. "Porcupine Research, Alaska Department of Fish and Game." Alaska Department of Fish and Game, 2010, www.adfg.alaska.gov/index.cfm?adfg=wildlifenews.view‗article&articles‗id=491. Accessed 11 July 2023.
Mützel, Gustav. "Porcupine." Maine.gov, www.maine.gov/dacf/php/gotpests/othercritters/factsheets/porcupine-vt.pdf. Accessed 21 Aug. 2024.