I’m sure most of you know what porcupines are — weird animals with big sharp spines that you should definitely avoid. But how much do you actually know about porcupines? What do they eat? How do they reproduce, with all those spines? What are porcupines, really? Let’s find out!

Though we may not be able to fully answer the existential question of what porcupines are, they are classified as rodents. There are two major branches of porcupines, which are not particularly closely related. The North American porcupine belongs to the New World family of porcupines, known as Erethizontidae. They are widespread in North America, being found in most of Canada, the United States, and northern Mexico.

With such a wide geographical range, it’s no surprise that porcupines are able to survive in a variety of habitats. They are precocious climbers, and are often found in forested areas, though they can survive in shrublands and tundra.

Though they aren’t the largest species of porcupine, North American porcupines are one of the largest rodents in North America, second only to the North American beaver. They measure 60 to 90 cm without their tails, and can weigh up to 18 kg. They are dark brown or black with some white markings that serve as warnings to potential predators.

Can you see why porcupines might have trouble staying in trees? Image Garry R. Osgood, CC BY-SA 3.0, via Wikimedia Commons, cropped

Because as we all know, you really don’t want to go hunting for porcupines. They are covered in about 30,000 quills, which are pointy, barbed, and very nasty. These quills are hollow modified hairs, and though porcupines can’t actually launch their quills, they are an excellent defence mechanism. 


When a porcupine feels threatened, it tenses the muscles beneath its skin, which causes the quills to stand up. If the predator ignores the porcupine’s warning colouring, clacking teeth and strong odour, the porcupine will turn around and swing its tail at the threat. The unfortunate predator will get a face full of quills, which detach fairly easily when erect. The barbed ends of the quills make them very hard to remove.

While most predators are deterred by the porcupine’s spiny armour, there are a few intrepid animals that successfully hunt porcupines. The most notable is the fisher, a small weasel-like animal that will force porcupines to the ground and then use their agility to dodge tail attacks from the cornered porcupine. Once the porcupine tires, the fisher flips it over and attacks the unprotected underbelly. Cougars also prey on porcupines, but their strategy is more focused on knocking them out of trees and hoping they die, or just sucking it up and taking some quills to the face.

Unfortunately, porcupines are not immune to their own quills. Porcupines like to climb trees — both for protection and to feed. They feed on twigs, roots, berries, bark and needles from trees. But there’s a problem: yummy, delicious buds and twigs are often located at the end of small branches. And in reaching for said tasty morsels, porcupines risk falling from trees. Which they do. Fairly often.

Falling from a tree is not a fun thing for anyone, but when you’re covered in sharp knives, there’s a serious risk of impaling yourself. So porcupine quills actually have antibiotic properties, which may help prevent self-inflicted wounds from becoming infected. Of course, antibiotics can’t protect a porcupine from every type of injury, and falls can be fatal. 

A cute little porcupette! Image by California Department of Fish and Wildlife, by CC 2.0 from flickr

Mating in porcupines is an understandably delicate affair, with participating porcupines holding their quills as flat as possible to avoid injuring one another. The mating season occurs in October and November, with females secreting mucus that attracts nearby males. Males may compete for access to a female, and the winning male will court her by lovingly spraying some urine on her, after which they head to the ground to mate.

After a relatively long gestation period (for a rodent) of around 200 days, porcupines give birth to a single baby. Adorably, baby porcupines are known as porcupettes, which has got to be one of the cutest names ever. Thankfully, porcupettes are born with soft quills, which quickly harden after birth. The porcupette stays with its mother until about five months of age at which point they disperse.

Porcupines truly are amazing creatures. So well-protected they can lumber around with little fear, but clumsy enough they had to evolve a way to protect their wounds from the inevitable times when they stab themselves. Nature is incredible.

Cover image by U.S. Fish and Wildlife Service Northeast Region, Public domain, via Wikimedia Commons