By Monica Macoubrie, Wildlife Education Specialist
One of my favorite topics to share with people in Nebraska — besides reptiles, of course — is porcupines. I love seeing people’s reaction when they realize these large-sized rodents live right here in our state.
Porcupines are slow, quirky and full of surprises. Even though most Nebraskans have never seen one in the wild, they’re out there quietly doing their part for the ecosystem and showing off some pretty incredible adaptations.
Not all porcupines are built alike. There are two big groups: Old World porcupines found in Europe, Asia and Africa and New World porcupines found in North and South America.
Old World vs. New World Porcupines
Old World porcupines are the ones with the dramatic quills. They tend to be bigger, stockier and more ground-dwelling. Their quills are clustered in thick bands and can be a foot long — warning predators to think twice. These porcupines don’t climb much. Instead, they waddle around on the ground, often in groups, and rely on those massive quills for defense.
New World porcupines are smaller and have quills that are mixed in with fur, giving them a shaggier look. Instead of sticking to the ground, they’re excellent climbers. They are more agile than their Old-World cousins and spend much of their lives in trees. The North American porcupine falls into this group.
So, while both groups share the recognizable “don’t touch me” defense system — quills — how they live, look and move around in the world is different.
The North American Porcupine
North American porcupines are slow-moving, mostly solitary rodents. In fact, they’re the second-largest rodent in North America, right behind the beaver. Despite their laid-back pace, they have some surprisingly clever adaptations. Much of their time is spent in trees, where they feed on leaves, buds, bark and twigs, especially from aspen, cedar and other shrubs and trees common in Nebraska’s woodlands and forests. In winter, when fresh leaves are hard to come by, they rely heavily on bark and evergreen needles. Porcupines are mainly nocturnal, venturing out at night to forage while avoiding most predators.
One key nutrient for porcupines is nitrogen, and winter can be a tough time because their diet is low in it, causing them to lose weight. To cope, porcupines have a special adaptation that reduces nitrogen loss in their feces. They can digest very high-fiber foods more efficiently than some other herbivores because food stays in their digestive system longer — a handy ability that helps them survive on a sparse winter diet.
Their habitats vary from forests and woodlands to brushy hillsides, but they always need trees or rocky areas for climbing and shelter. While they may look clumsy, porcupines are excellent climbers and swimmers. Their quills are hollow, giving them a built-in life raft for swimming in lakes, ponds and rivers.
The Quills
Porcupines are best known for their sharp quills, but there’s a lot more to them than just a spiky exterior. Those quills are actually modified hairs made of keratin — the same stuff as our fingernails — and they come in different lengths and thicknesses depending on the species.
North American porcupines have quills mixed in with softer fur, which helps them blend into trees and shrubs. When a predator gets too curious, the barbed quills stick, and they’re not coming out easily. Dogs, in particular, often get quills stuck in their faces or paws, and it’s always safest to have a veterinarian handle removal — pulling them out yourself can break the quills underneath the skin and increase the risk of infection.
Here’s a common myth: Porcupines do not shoot their quills. They simply detach when touched, leaving a sharp “reminder” for anything that gets too close. Quills aren’t just for defense, either. They also help porcupines regulate their body temperature.
One question we hear a lot is, “Can porcupines hurt themselves with their own quills?” And the answer is yes. It’s called “self-quilling.” This usually happens when a porcupine falls out of a tree or tumbles awkwardly and ends up impaling itself. Luckily, porcupines have a natural antibiotic in their bodies that helps reduce the risk of infection from these accidents.
Porcupine Predators
Even with their impressive quills, North American porcupines do have predators — but not many are willing to take the risk. Fishers, a type of weasel not found in Nebraska, are one of the few animals that regularly hunt porcupines. They’ve got a clever technique: flipping the porcupine onto its back to get past those sharp quills and go for the unprotected belly.
Coyotes, bobcats, mountain lions and great horned owls may occasionally take a porcupine but usually only if the porcupine is sick, injured or young. Most predators think twice before dealing with a fully-grown porcupine, which is one reason these spiky mammals can live relatively long lives despite being slow movers. Those quills really do earn their keep!
Porcupine Reproduction
How do porcupines mate? Carefully.
When it comes to reproduction, North American porcupines have one of the more unusual courtship rituals among mammals. Breeding season begins in late fall and can last through early winter, when males become more vocal, restless and territorial. They will often compete for the attention of a receptive female, sometimes engaging in loud squabbles or even physical fights that can leave both covered in quills.
Courtship itself is surprisingly dramatic: Males follow females through the trees, marking branches with scent to signal their presence, and they may even perform an unusual behavior of spraying urine on the female as a way of announcing readiness to mate. Once a female chooses a mate, actual copulation takes place carefully — despite the quills — usually high in the safety of a tree branch. After a lengthy gestation of about seven months, females give birth in late spring or early summer to a single young, called a porcupette.
Unlike many other mammals, porcupettes are born well-developed, with eyes open and soft quills that harden within the first week, giving them immediate protection from predators. The mother nurses her young for only a few weeks before gradually introducing it to solid foods, and by late summer, the youngster is capable of foraging on its own, though it may remain near its mother for some time before becoming fully independent.
North American porcupines may not be the fastest, flashiest or most graceful animals in the woods, but they’re some of the most fascinating. They shape forests, feed predators and add a little wonder to the landscapes they call home.