Columbian ground squirrels hibernate for 8-9 months of the year. This means that well over half of their lives is spent in a state of dormancy, with body temperatures falling to near 0°C. The physiological machinery that permits such a dramatic transformation has attracted the interests of scientists for decades. What has attracted my interest, are the ecological and evolutionary ramifications of hibernation. We are monitoring natural hibernation expression in Columbian ground squirrels in southwest Alberta. We have shown that emergence date from hibernation is a heritable trait (and, hence, has evolutionary potential if subjected to appropriate selection) and that the date of emergence influences the survival and reproductive success of females. Early reproduction is favourable, but an underappreciated aspect of climate change (increased winter precipitation) has led to delayed emergences over the past 20 years. We are now expanding these research directions to look at when individuals enter hibernation in the fall, what are their body temperature profiles during hibernation, and what are the metabolic rates of individuals throughout various periods of the year.
Graduate Students Involved: AdrianaLucíaGuerreroChacón (Ph.D. student) Rebecca Smith (M.Sc. student) Gabriela Heyer (M.Sc. student) Representative Publications:
Lane, J.E., L.E.B. Kruuk, A. Charmantier, J.O. Murie and F.S. Dobson. 2012. Delayed phenology and reduced fitness associated with climate change in a wild hibernator. Nature 489: 554-557.
Lane, J.E., L.E.B. Kruuk, A. Charmantier, J.O. Murie, D.W. Coltman, M. Buoro, S. Raveh and F.S. Dobson. 2011. A quantitative genetic analysis of hibernation emergence date in a wild population of Columbian ground squirrels. Journal of Evolutionary Biology 24: 1949-1959.