Desert tortoises in the Mojave annd Colorado deserts
Berry KH and Medica P. 1995. Desert tortoises in the Mojave annd Colorado deserts. Pages 135-137. In Our living resources: A report to the nation on the distribution, abundance, and health of U.S. plants, animals and ecosystems. National Biological Service, U.S. Department of the Interior. Washington, D.C.
The desert tortoise has been identified as six distinct populations for the purposes of critical habitat protection and long term conservation within the Mojave-Colorado Desert complex. Surveys have been conducted for 2-10 years. Most populations appear to be in decline with two exceptions – Ward Valley and upper Virgin River.