Porcupines and the winter woods

Porcupines are one of the most unusual creatures you can find in the woods.

They are one of the slowest moving creatures in the northern woods, generally waddling along at a seemingly carefree pace.

Yet they are difficult to catch sight of much of the year.

Now is the exception, though. If you want to lay eyes on a porcupine, winter offers your best chance.

It’s a matter of shrinkage.

Porcupines are herbivores, or plant eaters. In spring and summer, they feast on young buds, shoots, berries, leaves and other foods that make up their generalist diet.

Come fall, between September and November, they mate.

Then, winter puts them into survival mode. They do not hibernate. But with food supplies limited – they eat acorns and the like, but largely get by on the inner bark and needles of conifers, hemlocks especially — they move less. Wintertime home ranges might be 20 acres, or one-half to one-third that of their summer size, said the Pennsylvania Game Commission.

And it can be even smaller.

Porcupines spend the winter in dens. They love a rocky outcrop if they can find one. But porcupines also use hollow trees and downed logs, according to the Maryland Department of Natural Resources.

If a porcupine can find a den near a suitable hemlock, it might spend the entire winter traveling between the two, and no further.

That’s when you can find them because the signs will be obvious.

Porcupines often use the same dens year after year, sometimes sharing them with other animals. When that’s the case, dens show readily-visible signs of heavy use. Namely, their openings are often littered with feces, as the porcupine or porcupines shovel them out of the way.

The ground around trees they’re feeding on will often be littered with broken branches and twigs.

Then, too, porcupines often wear an evident path between the den and the tree or trees that are sustaining them. They really show up in snow, but even when it’s absent they can be deciphered.

Watching such trails early and late in the day – porcupines are most active then and after dark – or even setting up a trail camera along those routes often produces sightings.

That may be as close as you want to get.

Porcupines are covered with about 30,000 of the distinctive quills responsible for their other name, quill pig.

“They cannot throw or shoot their quills,” says the National Zoo. “But because quills are so lightly attached, they come off easily when a predator encounters them.”

And as every bird dog hunter whose canine has tried grappling with a porcupine knows, they’re a bugger to remove, too.

The quills are hollow – that’s why porcupines swim so well, they float – and feature barbed ends. Once stuck in another creature, those scaly barbs swell and pull the quill ever deeper.

Consequences can be severe.

“When a quill lodges in tissue, actions of the victim’s muscle fibers engage the tips of the scales, drawing the quill or quill fragment inward up to an inch a day. A wild animal badly impaled in the body will suffer intensely; quills may pierce its heart, arteries, or lungs and cause death, or they may sever the optic nerves and cause blindness,” says the Game Commission.

Some animals have figured out how to beat a porcupine. Coyotes, fishers and bobcats “learn to attack the porcupine’s belly, where there are no quills,” Maryland’s wildlife agency says.

But for everyone and everything else, it’s best to look but not touch.

What the future holds for porcupines is unclear.

They are not in trouble necessarily. According to the National Zoo, their range still extends from Canada through the northeastern and western regions of the United States and northern Mexico.

But, Maryland officials say, the presence of the hemlock woody adelgid – an invasive bug that is impacting the sustainability of hemlock forests in places – is a threat.

“Although the porcupine is not in danger of becoming extinct any time soon, it is worth the effort to keep an eye on this solitary creature. Its fate can tell us quite a bit about our relationship with the natural world, a world upon which we humans are still dependent,” the agency says.

So, when hiking, snowshoeing, skiing or otherwise exploring the winter woods, keep an eye out for the unique porcupine. They’re not rare, but always fascinating.

Bob Frye is the Everybody Adventures editor. Reach him at (412) 216-0193 or bfrye@535mediallc.com. See other stories, blogs, videos and more at EverybodyAdventures.com.

The porcupine file

Here’s a detailed look at the North American porcupine.

Size: Second only to the beaver in terms of rodents in North America, porcupines weigh about 20 pounds when full grown and are 2 to 3 feet long.

Habits: While they spend most of their time on the ground, porcupines are equally adept at climbing trees and swimming.

Reproduction: Porcupines have an, uh, unusual courtship. It involves a lot of vocalizations, some of what might be called dancing, and then the male showers the female with urine. Females give birth to one baby, called a porcupette, 205 to 217 days later.

Young: Porcupettes stretch 10 inches long and weigh about 1 pound at birth. Their eyes are open. They nurse for about 50 days, strike out on their own almost immediately, and breed themselves at 15 to 16 months of age, in their second autumn.

Life expectancy: Porcupines live as long as 10 to 12 years in the wild, and up to 18 years in captivity.

Problems: What gets porcupines in trouble around people? Their love of salt. In the wild, they get it from eating things like shed deer antlers. Around people, though, they frequently gnaw on anything and everything touched by sweaty hands: axe and shovel handles, gloves, rope and the like. They also love the glue in plywood and more than a few meet their demise along roadsides, where they congregate to nibble road salt.

Self defense: When attacked, porcupines often turn their backs on their attacker. They hide their head between their legs and flail their tail, flashing the quills that can reach up to 4 inches in length. They chatter to sound nasty, too.

Source: PA Game Commission and National Zoo