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Idaho Fish and Game

Meet a native Idaho rodent: the porcupine

The veterinarian removing the quills said that all dogs are different. Some learn their lesson the first time and never go after a porcupine again. Others feel a need to get even and they take out their anger on all porcupines√Čno matter how much it hurts. Apparently, having over 200 quills removed from her face, mouth and tongue was enough for my lab to learn that she didn't like porcupines. Although she encountered many more she never grabbed one again. We were on a ruffed grouse hunt in Southeastern Idaho when she met her first porcupine in some dense cover. How was she to know it wasn't a good plan to grab it and try to bring it to me? Porcupines are common here in Idaho, but most people don't know much about them beyond the fact they have sharp quills that can be very painful. Porcupines are rodents, as are mice, beavers, and squirrels. There are around 45 species of rodents found in Idaho. The beaver is the largest, the porcupine the next largest. Adult porcupines can weigh around 30 pounds. Probably the most prominent feature of any of the rodent species is the front teeth that are a yellow-orange color on the front surface and white on the back of the teeth. The orange surface is a special enamel that helps keep a rodent's teeth sharp. Every time a rodent chews, the two layers are worn unevenly and in the process the teeth are sharpened to a chisel- like edge. Tooth wear for a person is a problem. But a rodent's teeth never stop growing in their lifetime, so there is more tooth coming in to replace what was worn off. Rodents are important in the food chain, as most rodents are a food source for many other animals. But porcupines? Only a few species have figured out how to safely eat porcupines. Adult porcupines are about 20 inches long (not counting their tails) and they weigh from 10-30 pounds. In warm seasons, they eat grasses, leaves, clover, wildflowers and other vegetation. They can swim, so they can access various aquatic plants. In fall, they add fruit and berries to their diet. In winter, they eat primarily bark of hemlock, fir and pine. Where available, they also like bark of maple, beech, birch, elm, cherry and willow. They eat many various woody shrubs. They have poor vision but an excellent sense of smell that leads them to food. Porcupines can cause damage. They can kill trees by stripping the bark for food. They gnaw on woody objects including homes and garages. They especially like wood products that contain adhesives such as plywood and composites. They love salt and frequently chew up garden tool handles for the salt that is left from human sweat. They are many reports of expensive graphite fly rods left outside overnight that were chewed up by porcupines. Porcupines are most active at night. During the day, they can often be sighted snoozing on a tree branch. When not in trees or feeding, they spend time in rock crevices, caves, hollow logs, and under houses and outbuildings. They are not territorial and have a home range that can be as large as 200 acres. Although you are not likely to hear them, they make a wide range of sounds. If you would like to hear some of these peculiar vocalizations, there are several videos on YouTube where you can hear some. One fall, I was bowhunting for deer from a stand in an old apple tree. A porcupine wandered out of the woods, came to the tree I was in and climbed up the trunk, higher than the branch I was standing on. It never saw me until it was above me. Once it noticed I was in the same tree, it let out some shrill squeals before grabbing an apple in its mouth and "hurrying" down the tree. It waddled back into the woods and out of sight. It didn't move all that fast. With thousands of quills, porcupines don't need to be fast as most predators will leave them alone. When a porcupine feels threatened, it turns its back to the threat and its quills come up like the hair on a dog's back. Quills cannot be thrown, but they come off the porcupine very easily upon contact. Species that have learned how to prey on them without getting too many quills include fishers, coyotes, bobcats, mountain lions and wolves. These predators roll the porcupine onto its back to expose the stomach where there are few quills. Just this week, a famous ground hog emerged from his den to predict the weather. Similarly, a captive porcupine named "Teddy" has an impressive track record of predicting the winner of the super bowl. An ear of corn is placed next to each of two cardboard helmets that represent the teams in the game. The ear of corn he chooses to eat is next to the helmet of the team he thinks will win. He has predicted outcomes four times and has been right three of the four. His only miss was last year. He predicted the Seahawks would beat the Patriots. He really can't be blamed for missing that one. He didn't expect a pass play would be called in that situation either.