Kinship and use of underground space by adult female Richardson's ground squirrels (Urocitellus richardsonii) / Catherine Ovens
University of Lethbridge. Faculty of Arts and Science
Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences, c2011
Although female Richardson’s ground squirrels (Urocitellus richardsonii) spend 80% of their lives sleeping and hibernating underground, studies on interactions and space-use have historically focused on the 20% of the time they spend aboveground. The type and frequency of aboveground interactions and degree of home-range overlap among female Richardson’s ground squirrels depend on their reproductive status and degree of kinship. The purpose of my study was to determine whether reproductive status and kinship influence underground sharing of space as well. I radio-collared 54 adult female Richardson’s ground squirrels (18 in 2008, 30 in 2009, and 6 in both years) of known maternal kinship in 5 spatially adjacent matrilines at a field site near Picture Butte, Alberta, Canada. Radio-collared females were located underground every evening after they retired and every morning before they emerged during both the 2008 and 2009 active seasons to determine sleep-site use and sleep-site sharing. The locations at which females were observed to retire in the evening (170 evenings) and emerge in the morning (141 mornings) in 2008 and 2009 were used to determine underground connections between surface entrances and underground sleep sites. Females commonly shared burrow systems, sleep sites, surface entrances, and underground connections after emergence from hibernation until mid-pregnancy and they shared again, though less frequently, after litters had been weaned, but they never shared underground features during lactation and hibernation. Close kin shared underground space more frequently than distant kin, and distant kin more frequently than non-kin. Variation in underground sharing of space over the active season and selective sharing with respect to kinship suggest that reproductive status and degree of kinship influence underground sharing.
xii, 121 leaves ; 29 cm
Richardson's ground squirrel -- Behavior , Dissertations, Academic