Mountain Beaver: The Little Rodent with a Large Appetite

Authors

Wendy M. Arjo, National Wildlife Research Center’s Olympia Field Station

Document Type

Article

Date of this Version

July 2003

Comments

Published by WESTERN FORESTER ; JULY/AUGUST 2003

Abstract

While walking through open forest areas you might have found yourself falling into large holes that dot the landscape. After extracting your foot from the hole you may have noticed other holes nearby, some with clipped sword fern or forbs neatly arrayed around the hole. These symmetrical burrows are home to the mountain beaver. The mountain beaver, considered the most primitive living rodent species, descended from a now extinct family of rodents over 30 million years ago. Seven subspecies of mountain beaver are recognized with one subspecies in coastal California currently listed as an endangered species. This semi-fossorial rodent, endemic to the Pacific Northwest and California, is among a variety of herbivores that retard growth and cause seedling deformities and mortality.