WildEarth Guardians

Tuesday, November 20, 2012
Feds Announce Peñasco Least Chipmunk Warrants Protection under Endangered Species Act

Rare declining subspecies is an indicator of failing forest health
Contact: Taylor Jones (303) 353-1490

Washington, DC –  The U.S. Fish and Wildlife Service (FWS) announced today that the Peñasco least chipmunk (Tamias minimus atristriatus), a subspecies of least chipmunk endemic to the White and Sacramento mountains in  New Mexico, is warranted for listing under the Endangered Species Act (ESA). The agency declined to proceed with listing now, however, stating that it is precluded by other, higher priorities. The subspecies has been added to the list of candidate species awaiting formal protection under the ESA.

“The decline and near-extinction of the Peñasco least chipmunk is like a flatline on the heart monitor of ponderosa pine forests,” said Taylor Jones, Endangered Species Advocate for WildEarth Guardians. “We need to go into red alert to save this chipmunk and its dwindling habitat.” 

The single greatest threat to the Peñasco least chipmunk is the loss of mature ponderosa pine forests. Ponderosa pine forest once occupied large areas in the White and Sacramento mountains. Original uncut ponderosa pine forest formed open, park-like stands – a mosaic of large trees scattered or clumped in groups and including small patches of dense young ponderosa – within a grassland matrix. Now, with the exception of some small, inaccessible areas, all ponderosa pine forests in the White and Sacramento mountains have been logged.

Changes in the composition of ponderosa pine habitat also fragment chipmunk habitat. Logging, livestock grazing, and fire suppression, among other factors, have radically altered the structure of ponderosa pine forest. Large areas of ponderosa pine have been eliminated or have shifted from stands of mature trees with open understory of abundant and diverse herbaceous vegetation to dense stands of younger trees. These changes in forest structure makes the Peñasco least chipmunk more vulnerable to competition from the larger, more arboreal gray-footed chipmunk (Tamias canipes) with which it shares its range. The Peñasco least chipmunk is further threatened by climate change, biological vulnerability due to its limited range and small population size, and the cumulative effects of these myriad threats.

WildEarth Guardians submitted a petition to FWS to list the Peñasco least chipmunk in September 2011. The agency announced both an initial, positive petition finding and a warranted-but-precluded listing determination in the 2012 Candidate Notice of Review, which will be published in the Federal Register tomorrow.