Identification and Distribution of Spiny Pocket Mice (Chaetodipus) in Cismontane Southern California

Abstract

The San Diego Pocket Mouse (Chaetodipus fallax) and California <br /><br />Pocket Mouse (C. californicus) frequently are confused with each other. The <br /><br />shorter, more rounded ears of San Diego Pocket Mice, and to a lesser extent their <br /><br />smaller hind feet, are the best external means of distinguishing them from Cali- <br /><br />fornia Pocket Mice. The two species are largely allopatric, californicus to the <br /><br />north and fallax to the south, but their ranges overlap somewhat in cismontane <br /><br />southern California. California Pocket Mice occupy higher elevations in this area <br /><br />and farther south, whereas San Diego Pocket Mice are generally found at lower <br /><br />elevations and extend no farther north than southeastern Los Angeles County.