Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (1.3 MB)

Title: Distribution and Climatic Relationships of the American Pika (Ochotona princeps) in the Sierra Nevada and Western Great Basin, U.S.A.; Periglacial Landforms as Refugia in Warming Climates

Author: Millar, Constance I.; Westfall, Robert D.;

Date: 2010

Source: Arctic, Antarctic, and Alpine Research Vol. 42(1): 76-88

Publication Series: Scientific Journal (JRNL)

Description: We used a rapid assessment to survey American pika (Ochotona princeps) populations and documented 420 pika site occurrences in southwestern U.S.A. These included 329 sites from the Sierra Nevada (SN), California; 67 from six southwestern Great Basin (swGB) ranges, California and Nevada; 16 from three central Great Basin ranges, Nevada; and 8 from the central Oregon Cascades. Of these, 67% were currently occupied, 27% modern (indirectly scored active), and 6% old. Sites were grouped into 148 demes, 88 regions, and 11 mountain ranges. Current elevations ranged from 1645 m (1827 m excluding Oregon) to 3887 m, extending the lower elevational range of the species at the study latitude. Sites were distributed on all slope aspects with a preference for north to easterly aspects, and without preference for substrate. Rock-ice-feature (RIF) till, notably rock-glacier and boulder-stream landforms, accounted for 83% of the sites. Climatic relationships from the PRISM model for the SN and swGB sites showed wide tolerance, with average precipitation 910 mm, average minimum temperature 23.9 uC, and average maximum temperature 8.7 uC. Average minimum temperatures for old sites were not significantly different from recent sites, whereas average maximum temperatures were significantly higher in old sites. Unusual features of RIF landforms make them important refugia for pikas as climates warm. In contrast to studies that document species vulnerability elsewhere, pikas in the SN and swGB appear to be thriving and tolerating a wide range of thermal environments.

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

XML: View XML

Citation:


Millar, Constance I.; Westfall, Robert D. 2010. Distribution and Climatic Relationships of the American Pika (Ochotona princeps) in the Sierra Nevada and Western Great Basin, U.S.A.; Periglacial Landforms as Refugia in Warming Climates. Arctic, Antarctic, and Alpine Research Vol. 42(1): 76-88

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.