Creature Feature: the North American Porcupine

April, 2016

Many long term residents of Humboldt County have been asking themselves the same question: Where did all the porcupines go? This question revolves around the North American Porcupine, an animal that lives from northern Mexico to Canada. Once spotted throughout Humboldt County, it is now limited to a few locations. 

The porcupine can’t be missed when spotted—it can grow from two to three feet and weigh up to 30 pounds. And, of course, its back is covered with upward of 30,000 quills, each tipped with microscopic barbs. These barbs are designed to lodge into attackers and move deeper into muscle tissues over time, sometimes leading to the death of the predator. The quills allow the herbivorous porcupine to resist predation despite its sluggish, lumbering movements. They even prevent the porcupine from slipping off of trees when climbing. 

The porcupine can make a home in  tundra, forest, and a variety of climates and elevations. While on the east coast they spend most of their time in trees, in the Pacific Northwest they live the majority of their life on the ground. Depending on what region they are in, porcupines may change the nature in which they feed themselves. Porcupines living in Massachusetts, for example, rarely feed on tree bark, while tree bark is essentially all the Texas species eat.

Porcupines can live up to 18 years but are limited by the health of their teeth; being worn down from consuming trees makes eating more difficult with age.

Overall it is a special and unique creature that is recognizable across North America. However, porcupines are no longer a common sight in Humboldt County. Tim Bean, a professor at Humboldt State University began to research and found that there are still small groupings of them near Bear River Ridge and Tolowa Dunes State Park. It remains unknown why they are absent from Humboldt County.

Some hypothesize that porcupines were never native to this area, simply arriving with the growing timber industry to eat fresh bark. Perhaps due to the decrease in clear-cutting and increase in forest management, they have moved to new areas. Others say predation is driving them out as fisher populations begin to return, or that cannabis trespass grows and the rodenticides growers use are harming porcupine populations. 

While less common in our region today, porcupines are not considered threatened. Go looking for a porcupine in Tolowa Dunes State Park and see if you can spot one of these antisocial critters. If you are so lucky, be sure to record it at, a website Bean has created through his Northern California Porcupine Project to track the north coast porcupine to determine why they mysterious disappeared from California.

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