A Prickly Tale
by Marge Hermans and Bob Armstrong
Photos by Bob Armstrong

On a drizzly morning in May, a 5-year-old female porcupine gives birth in the hollow of a tree somewhere in Southeast Alaska. Her newborn—also a female—is about 10 inches long and weighs about a pound. The young porcupine is quite well developed. Her eyes are open, and tiny teeth have already emerged. Except on her belly, she is covered with dense black hair. Amid the hair are soft barb-less quills that will harden and begin to provide defense against predators within about an hour. But for now the young porcupine is hungry. She nurses for about 30 minutes, then curls up and falls asleep.

For several weeks before the birth the mother porcupine has been eating the newly emerging vegetation of spring: salmonberry shoots, violets, marsh marigold, horsetails, and twisted stalk. Already she is regaining some of the weight she lost during winter, when she lived on the needles and inner bark of Sitka spruce and hemlock trees, less nourishing and more difficult to digest than the foods available in summer. She has been pregnant for 217 days (about 7 months), since mating with a large male in October. She will nurse her newborn for 3 ½ months, until mid- or late August, while the youngster gradually learns to find and select nutritious leaves and other vegetation on her own. Female porcupines produce a single offspring nearly every year, and they invest considerable time and effort to bring an individual to maturity.

Early July. In the full flush of summer, the female porcupine has climbed about 10 feet up into a gangly Sitka alder shrub. She is stripping leaves from its outermost branches. Her daughter, not yet able to climb trees very well, is hiding in a tangle of brush a short distance away. The adult female clings to the narrow branch, holding tight with her strong thigh muscles. She reaches her forepaws toward the outermost branch tip and strips its leaves with her long, curved claws. She seems ravenous, stuffing leaves into her mouth and chewing furiously. She’s harvesting the newest and some of the tastiest and most nutritious growth on the tree.

The female’s fur is thick and brownish-black with long, single guard hairs that stick out past the rest of the pelt. Amid the fur lie an estimated 30,000 quills—dangerous white needles with black tips. They protect every part of her body except the under-parts, muzzle, and ears. Even if some are expelled against a predator, they will grow back in a matter of days.

Today it is the quills themselves that have attracted potential predators. Two women have spotted the porcupine in the tree and hope to gather quills to make jewelry. As they scramble through the brush to the base of the small tree, the porcupine hunches against the branch. Her quills spring up and fan out, their barbed tips pointing in every direction. She shivers, then closes her jaws, and her teeth make a chattering sound; she emits a strongly repellent smell.

Still, one of the women begins to climb the flimsy tree, reaching toward the porky with a long-handled broom wrapped with a towel. Branches sway precariously, and the porky shifts her weight, balancing with her broad, club-shaped tail. The woman gets closer.
Whomp! Before the broom can touch her, the porcupine flings her tail to the side and delivers a powerful blow. The shrub sways back and forth wildly, and the startled woman slips and falls several feet to the ground.

“Jeez, what a whap! Who’d think a little guy like that would be so strong?” she says to her companion. She looks at the 30 to 40 quills embedded in the towel-covered broom. “I think this’d better be enough. We’ll really be in trouble if that thing falls down on us!”
The women leave, and the female porcupine eventually lowers her quills and continues feeding. Toward evening she will climb down to be reunited with her daughter. They are constant companions now, but gradually they will become less so. By October, her daughter will be capable of climbing and feeding herself, and she’ll probably wander off on her own.

Mid-October. The adult female, approaching estrus, is leaving a scent trail wherever she goes. That has attracted three males as suitors, and they fight among themselves to win her affections. Their combat is vicious. Even the large, winning male ends up bedraggled and carrying several of his rivals’ quills.

The female waddles into dense underbrush, and the winning male pursues her in earnest. Whenever he approaches too close, she howls, making a sound like a cat yowling or a baby crying. She has complete control over this prickly courtship, and will move her heavily quilled tail to allow intimate contact only when she is ready for mating.

January. Back from the mouth of a river, overlooking half-frozen sloughs and tidal flats that spread out for half a mile, clusters of tall Sitka spruce and western hemlock line the steep bank. Two medium-sized spruce trees stand out from the others because of their odd, sparse silhouettes. In the top third of the trees, many branches are lacking needles and lateral twigs. The uppermost branches are virtually naked. Amid their lush neighbors, these trees look like bottle brushes worn down from overly conscientious scrubbing.

The cause of their distress—the female porcupine—has returned for a second year of feeding in the trees. Against the bright backdrop of a winter sky, she is a dark lump that moves slowly up and down the tree. She has spread all four limbs around the trunk, using all the special features porcupines have developed for climbing. Her sharp claws dig into the bark, and the nubby, rubbery surfaces of her palms and the soles of her feet create friction for grasping the trunk.

She uses her tail as a brace. When she is climbing up, she uses the stiff, backward-pointing bristles on its underside to keep from sliding down. When she is climbing down, she can lift the tail then lower it at each claw-hold to test the way below. Her belly, unquilled, slides easily against the trunk as she moves, and her unfurred soles and palms allow her to feel the contours of the tree as she navigates.

On the trunk the female strips off slices of bark, using at first the four curved incisors at the front of her mouth. These sharp teeth, covered with bright orange enamel that hardens them, are continually sharpened by scraping and their movement against each other. They grow continuously from deep inside the porcupine’s jaws. The porcupine can actually close her lips behind them while rasping off tough outer bark from the tree, which she will not eat. She is instead after the tender inner bark, which she will take into her mouth, grind with her cheek teeth, then swallow. Special bacteria in her gut will help with the long, difficult process of digesting her food.

The female also ventures out onto branches, attracted by needles and the thin bark on young twigs. But she weighs 14 pounds, and as she moves farther and farther from the trunk, the smaller branches bend precariously, waving up and down from the weight of her body. As if this is not frightening enough, at one point she stretches from one slender branch to the one above it, perhaps trying to save the effort of crawling all the way back to the trunk. Her whole body tips and sways as she grasps the upper branch with first one forepaw and then the other. But once she gets that far she cannot seem to let go with her two back legs. When she finally does, she dangles by her front legs, and hangs, swinging, with all four legs wrapped around the slender top branch.

The female may indeed be in a position as tenuous as it looks. Porcupines often fall, sometimes with dire results. Researcher Uldis Roze found porcupines in New York state with evidence of cracked skulls, fractured legs, and cracked hips, all apparently from falls. When he studied museum specimens to check for evidence of falls, he found more than a third of the specimens showed healed fractures, some of which surely disabled their victims, at least to some extent.

But this time the female does not fall. She painstakingly jimmies herself back toward the trunk where the branch is more stable.
Meanwhile, the pale winter sun reveals a second porcupine, smaller, in a nearby tree, but nowhere near as high up as the female is. Apparently her daughter did not move as far from her mother as we had thought. She is still less than a year old; yet despite their proximity she’s the porcupine equivalent of “grown up,” and she’s on her own.