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      During our first visits to Wellesley Island in the 1970s Leslie and I spent most of our time on the water -- like everybody else. Then one day we ventured into the wilderness beyond the golf course. We negotiated the thickets and on the other side of the ridge we saw a huge animal sleeping in a tree that reminded us of pictures we'd seen of great sloths. We were so excited we asked the director of the Nature Center on the Island, Bob Wakefield, to identify the animal. Though he probably knew exactly what we saw, he was so impressed with our excitement and Leslie's drawing of the "sloth" that he hiked out to the tree with us and did allow that it was one of the biggest porcupines he had ever seen.

Over the years I've seen countless porcupines up in the trees, and I wish I could say that I know a great deal more about them than I did back in1970, but I really don't. Porcupines are god-like and there is a great deal about them that seems unknowable and ineffable. I simply take on faith that when a porcupine climbs up a leafless tree in the teeth of brisk wind on a below zero day that it knows what it is doing. Let me hasten to add that many who study porcupines don't have so many doubts. Porcupines are slow animals and evidently once you hone your technique and invest in thick gloves, you can grab its tail, cage it, give it a shot, strap on a radio collar, and do proper scientific studies on it. I've never had that urge. Seeing a porcupine generally stops me in my tracks. If it's on the ground it generally ambles away. If it's in a tree, I might be able to watch it munch for a while, then it establishes eye contact and what hopes I had of making unobstrusive scientific observations fall as the porcupine's quills rise.

The best time to watch porcupines is in the winter, after a snowfall. They slow down so much that you can often stand near them and try to absorb the reality of their life:

their many hours in a rock den

along their long trails in the snow,

and as they climb trees

where they eat the bark for food.

Porcupines are able to live this slow paced, almost dull existence, because of some rather sharp attributes. Their sharp claws

make climbing trees easy. Their sharp quills

afford protection. And I cannot fathom what they see with their sharp eyes

Since they move about so often during the night, I suspect they rely a great deal on their sharp sense of smell.

However, let's not get carried away with sharp. Their teeth are rather dull.

though certainly get the job done.

Porcupines have strong jaws

Well, there is nothing like a photo of a skull to put an end to a rambling review and prompt an author to get down to some facts and true stories.

When writing about many mammals, I don't like using the singular. I usually see otters in a group and have observed as many as seven of them lying more or less on each other on top of a lodge. Beavers do go off alone but never for long. They rotate through the various work stations around the pond and when work is done as many as eight might huddle into one lodge. When I see two porcupines together they are often in the midst of a screaming row, contesting a tree or a rock den. One soon walks away. So I am comfortable writing about a porcupine.

A porcupine is a gentle mammal between the size of a cat and medium sized dog, arrayed with a fearsome coat of sharp quills which deters meat eating predators while it harvests vegetation in a range that generally doesn't extend beyond a few acres. It often goes further afield to find water.

And not only for a drink. In the spring especially I'll see porcupines pulling grasses out of the ponds and river and eating them.

While content with a relatively small range, it shifts its den frequently, not as much as otters, but it's seldom as sedentary as a colony of beavers.

It finds dens principally in tree trunks and among rocks. In the winter if the route of your daily hikes takes you by a porcupine's den, there's a good chance you'll find it there, maybe even sniffing the air.

A porcupine seems to seek shelter for reasons all its own. I've seen too many of them half in and half out on cold and wet winter days.

The rock dens they favor always seem to be in the shade, facing north, often the last areas to be thawed out. Predators sniff for warm bodies so perhaps denning on the cold side of a gully affords some protection, but few animals advertise where its den is as boldly as a porcupine. Usually there is a trail of poop, one tightly wound ball of thoroughly digested plant matter dropped every foot or do, with an accompanying line of pee, often almost red, lining the way to the den.

Its rock dens are often hard to get to,

and a porcupine generally picks one with plenty of room to back into. So if you wished a porcupine ill, just getting to its den in the rocks would still leave you with a good deal of effort.

However, porcupines who den in the holes at the bottom of trees, often lets loose a welcome mat of their poop.

One winter the porcupine staying in that den died, but every year since, a porcupine has moved in to spend part of the winter.

Another curiosity about porcupines and their dens is that sometimes a porcupines doesn't den. It spends the night, or several nights up in a tree. During a 48 hour cold snap, as far as I could tell since there were no new tracks in the snow, a porcupine stayed in one small maple tree, and seemed to say put because very little bark was eaten. When the cold snap ended, the porcupine left the tree but not before eating much of its bark.

I would like to report that porcupines always leave enough of a tree's bark uneaten so that the tree stays alive, but porcupines can be thorough especially in smaller trees and eat almost all the bark from the roots to the crown.

They can nip so many twigs and branches off a tree, especially hemlocks that it decrowns the tree.

Trees get their revenge in a fashion, as falling out of them is a major cause of porcupine deaths. In a sense that tastiest part of a tree, the bud at the end of fresh green shoot, lures the porcupine to a perilous position where one slip can be fatal. Twice I've seen porcupines that looked like they died while still in the tree. I saw them flat and lifeless on a limb with two claws dangling down. The porcupine in the left hand photo was facing the ridge I was walking on and I stood five feet from it asking if it was OK.


Both were taking a nap in the late afternoon and when it got dark were back gnawing away.

The renowned predator of the porcupine is the fisher, a carnivore over twice the size of a mink, and pound for pound not that much bigger than a porcupine, if you don't count its magnificent tail.

They are said to have the knack of attacking the porcupine's belly, the only place on its body where there are no quills. Only once have I followed a fisher's tracks that led to a dead porcupine

But I've also followed fisher tracks that seem to make a point of avoiding areas where there are porcupine dens.

I've never seen porcupines mate and I'm not sure if I've ever seen them mating. That can be a noisy affair with two porcupines screaming at each other in a tree. But they are supposed to mate in the fall, and I've heard them screaming in the spring and summer too. A porcupine mother only has one baby at a time, and, in my experience seeing them together is a rare thing. I saw a mother and her offspring on a tree in mid-June

The mother hurried up the tree leaving the little ball of quills far behind. Leslie bumped into a mother and a baby on hte ground. The mother hurried off leaving the baby to fend for itself. Not surprisingly I often see little porcupines on their own and they can be very engaging

and fearless. Not that I think their not getting out of my way is that fearless. What am I going to do with such a ball of sharp quills? Fearless is climbing out on a snow covered tree limb that hangs over the cold water of the St; Lawrence river. Some of the balancing acts they do when they get up in a tree can take your breath away



Bob Arnebeck

I also write about porcupines in my nature blog. And in my in my beaver blog

See my other web sites on otters, beavers, minks, Blanding's turtles and muskrats. Click the thumbnail: