Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 5-1970 On the Population Ecology of Uinta Ground Squirrels Spencer R. Amend Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Animal Sciences Commons Recommended Citation Amend, Spencer R., "On the Population Ecology of Uinta Ground Squirrels" (1970). All Graduate Theses and Dissertations. 4799. https://digitalcommons.usu.edu/etd/4799 This Thesis is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact
[email protected]. ABSTRACT On the Population Ecology of Uinta Ground Squirrels by Spencer R. Amend, Master of Science Utah State University, 1970 Major Professor: Dr. David F. Balph Department: Wildlife Resources A marked population of Spermophilus armatus averaging 529 individuals per year was studied for two and a half seasons on a 22-acre tract in northern Utah. The average date of emergence from hibernation of the first squirrel was 9 April. Mating occurred as soon as animals emerged from hibernation. The average date of appearance of the first litter was 31 May. Emergence sizes of litters were from 5 .2 for yearling females to 6.3 for adult females. Few instanc es of predation were observed . Age and sex ratios varied throughout the season and for different portions of the study area. The population increased 22 percent from 1964-1965 and 15 percent from 1965-1966.