Radiotelemetric study of hibernation under natural and laboratory conditions.

WANG, LAWRENCE C. H. Radiotelemetric study of hibernation under natural and laboratory conditions. Am. J. Physiol. 224(3): 673-677. 1973.-The body temperature of hibernating Richardson’s ground squirrel (Spermophilus richardsom) was measured by radiotelemetry both in its natural habitat and in the laboratory. Under natural conditions, hibernation extended from mid-September to early March. The minimum body temperature during hibernation decreased progressively from 17.5 C in September to 2.1 C in March. The length of each hibernation bout increased from 4 to 24 days between September and mid-February, and decreased to 3 days just prior to emergence from hibernation. The rates of cooling during entry into hibernation were comparable between field (0.016 C/ min) and laboratory (0.017 C/min) animals, and frequent leveling or temporary increase of body temperature was observed during the entry period. The rates of rewarming during arousal from hibernation were also comparable in animals under field (0.14 C/ min) and laboratory (0.17 C/min) conditions. The data indicated that by using radiotelemetry, general laboratory treatments did not bias the qualitative and quantitative measurements of body temperature observed in hibernating ground squirrels under natural conditions.