Meeting Abstract
P2.148 Tuesday, Jan. 5 Torpor patterns during hibernation in golden-mantled ground squirrels (Spermophilus lateralis) under natural conditions BURDETT, KA*; BUCK, CL; FLORANT, GL; Department of Biology, Colorado State University, Fort Collins, CO 80523; Institute of Arctic Biology and Department of Biology and Wildlife, University of Alaska Fairbanks, AK 99775; Department of Biology, Colorado State University, Fort Collins, CO 80523 kburdett@rams.colostate.edu
Golden-mantled ground squirrels (GMGS) have been used in lab hibernation experiments for many years. They undergo hibernation, defined as multi-day torpor bouts, to survive the winter. The torpor patterns of this species have been well studied under lab conditions, but little is known about their torpor patterns in the field. We hypothesized that under natural conditions there will be significant differences between gender and age classes, as well as having a significant difference in the torpor patterns of GMGS in the field compared with lab kept GMGS. To determine this, we surgically implanted body temperature data loggers (iButtons) into the abdominal cavity of GMGS and released them prior to the hibernation season (August 2008). Recapture and iButton removal took place in spring (May 2009). Animals hibernating in the field displayed long, sustained torpor bouts of 8-14 days on average with a maximum length of 21 days, decreasing their body temperature (Tb) to 0°C ±1°. Animals hibernating in the lab typically demonstrate torpor bouts of 5-7 days, with Tb around 6°C ±1° and ambient temperature at 5°C ±1°. In the field, adult males emerged earlier, spent less time in torpor, and had fewer torpor bouts that were shorter in duration, compared with females and juveniles in the field. These preliminary results support our hypothesis that torpor patterns differ both between lab and field, as well as between gender and age classes. Further studies are underway to make distinctions between gender and age classes in the field and lab.
