The Circannual Cycle of Richardson's Ground Squirrels in Southern Alberta
- 20 November 1979
- journal article
- research article
- Published by Oxford University Press (OUP) in Journal of Mammalogy
- Vol. 60 (4), 760-768
- https://doi.org/10.2307/1380191
Abstract
Times of spring emergence and autumn immergence were determined for Richardson's ground squirrels (Spermophilus richardsonii) in southern Alberta from 1975 to 1978. Spring emergence of females was synchronous and was not affected by their age, reproductive success in the previous year, or time of autumn immergence. Time of spring emergence correlated with climatic conditions, in particular with warming of the shallow layers of soil. Time of autumn immergence was asynchronous, even within the same age and sex class, and was affected by the condition of the animal. Factors affecting fattening, and hence immergence, included age and sex of the squirrel, its reproductive success that year, and the availability of food. Synchrony was reestablished in the following spring, suggesting that emergence is the point in the annual cycle at which entrainment occurs.This publication has 7 references indexed in Scilit:
- Time patterns and metabolic rates of natural torpor in the Richardson's ground squirrelCanadian Journal of Zoology, 1979
- Effect of age and parity on weight gain and entry into hibernation in Richardson's ground squirrelsCanadian Journal of Zoology, 1978
- Effect of climatic conditions on the annual activity and hibernation cycle of Richardson's ground squirrels and Columbian ground squirrelsCanadian Journal of Zoology, 1977
- Circannual Rhythmicity and Entrainment of Surface Activity in the Hibernator, Perognathus longimembrisJournal of Mammalogy, 1977
- Hibernation and Circannual Rhythms of Food Consumption in Marmots and Ground SquirrelsThe Quarterly Review of Biology, 1976
- Seasonal Changes in Weights of MarmotsThe American Midland Naturalist, 1976
- THE EFFECT OF TEMPERATURE AND PHOTOPERIOD ON THE YEARLY HIBERNATING BEHAVIOR OF CAPTIVE GOLDEN-MANTLED GROUND SQUIRRELS (CITELLUS LATERALIS TESCORUM)Canadian Journal of Zoology, 1963