North American Porcupine

## Description

The North American porcupine (Erethizon dorsatum ), also known as the Canadian porcupine, is a large quill-covered rodent in the New World porcupine family. It is the second largest rodent in North America, after the North American beaver (Castor canadensis ). The porcupine is a caviomorph rodent whose ancestors crossed the Atlantic from Africa to Brazil 30 million years ago, and then migrated to North America during the Great American Interchange after the Isthmus of Panama rose 3 million years ago.

## Appearance

The North American Porcupine is a well-known New World rodent. This slow-moving porcupine is the second North American rodent in size only to beaver. In addition, the range of this species is the northernmost of all porcupines. The animal has short legs and heavy build. The front half of the body exhibits long, yellowish guard hairs. The back and tail exhibit dark, coarse hairs with up to 30,000 characteristic quills, scattered among them. The quills of this animal are yellowish with black tips and have stiff, barbed around 3 inches-long spines. Once thrust into another animal's skin, these spines may become fatal.

## Distribution

Having the northernmost range of all porcupines, these rodents occur throughout much of North America, from the Arctic Ocean to northern Mexico. They inhabit most of Alaska and Canada, the northern part of the Great Lakes region as well as the west and northeast regions of the United States. North American porcupines live in coniferous and mixed forested areas, but have adapted to harsh environments such as shrublands and tundra. They make their dens in hollow trees or in rocky areas.

## Behavior

North American porcupines don't tend to display social behavior and are mainly found solitarily, although they do have a social structure. During the winter months, up to 8 individuals may live in the same den. During this period they are also known to forage in groups of up to 20 animals. They choose to forage in these groups in order to protect themselves from predators. However, some may prefer living and foraging alone. Each individual has its own territory, which it defends. Meanwhile, males of this species are more territorial, fiercely defending their home range. These nocturnal animals rarely go beyond their territories. They communicate with conspecifics through a system of acoustic, chemical, visual, and tactile signals. Thus, threatened porcupines turn away predators, using a chemical odor, which they give out by chattering their teeth. Competing males communicate through vocalizations.

## Diet

The winter diet of these herbivorous animals mainly consists of tree bark. During the rest of the year, they feed upon green vegetation such as leaves, twigs, and fruits, supplementing their diet by gnawing on occasional bones and antlers that are rich with mineral nutrition.

## Reproduction

North American porcupines have a polygynous mating system, where a dominant male breeds with multiple females. Breeding occurs only if a female wants to breed. The latter tries to get pregnant by the 'best' male. North American porcupines breed between October and November. A single young is born after a gestation of 210 days. The baby is nursed for 127 days, during which period the mother provides it with the required food. During the first 6 weeks, females are constantly nearby their young, meeting the babies only during the night. Mothers spend their daytime hours sleeping, while their young are hidden in a secluded place on the ground. Independence is reached at 5 months old, while the age of sexual maturity is 29 months old for males and 25 months old for females.

## Population

### Threats

Currently, there are no serious threats to the population of this species as a whole, although the animals are often hunted and trapped as pests due to damaging trees, crops, car tires, and other property. The population in Mexico is on the verge of extinction as a result of excessive hunting. In addition, North American porcupines suffer from collisions with automobiles.

### Number

According to IUCN, the North American porcupine is common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) and its numbers are stable.

## Fun Facts

The word 'porcupine' originates from 'porc espin', meaning ‘spined pig’ in Middle French. These animals were named 'quilled pigs' by Americans, but they actually rodents, which aren't related to pigs.

The main food of porcupines is tree bark. So, when passing through an area, it usually leaves some trees with stripped bark on its way, which helps detect the location of this animal.

Quills of these animals possess a topical antibiotic, which helps prevent infection. This antibiotic is mainly intended for self-defense, in a case if the porcupine is accidentally prickled by its own quills.

Foraging habits greatly differ among porcupines, depending on group and location. Thus, African porcupines usually forage on the ground, whereas those, native to North America, forage in trees.

The body of porcupine produces keratin - a material, from which its quills are made.

Due to being hollow, quills of this animal were used to keep gold dust. Presently, porcupine quills are often used as musical instruments.

Since porcupines love the salty flavor, they can consume axe handles, canoe paddles, outhouses, and even automobile radiator hoses.

When falling from a tree, this animal often gets stuck to a branch or something else on its way to the ground.

## References

https://animalia.bio/north-american-porcupine