by
Kari Benson
School of Sciences
Lynchburg College, Lynchburg, VA
Belding’s ground squirrels (Spermophilus beldingi) are diurnal rodents that live in sub-alpine meadows in the far western United States. Due to the extreme weather, the squirrels hibernate for seven or eight months of the year. They must enter hibernation with sufficient fat stores to survive this long hibernation. The squirrels spend their short active period by initially mating, then eating large quantities of food. They are primarily herbivorous, eating mostly seeds, flowers, and vegetation.
Adult females mate shortly after they emerge from hibernation. After mating, some males disperse to new groups; the others often return to hibernation before the young are born. The females establish territories within the social group and have between three and six pups. The pups emerge from their burrows when three to six weeks old, and the juvenile males disperse (leave to join new groups) shortly thereafter. The females typically remain in their natal (birth) group for life.
Paul Sherman (1977; 1981) studied Belding’s ground squirrel behavior. The squirrels are subject to many dangers, including predation by coyotes, weasels, and raptors. Often, if a squirrel spots a predator, it will stand up on its hind feet and call out an alarm. When others hear the alarm, they quickly retreat to their burrows. Not all squirrels are equally likely to call.
Image Credit: Photo of Belding’s ground squirrels by Don Baccus (dhogaza@pacifier.com), © 1999. Used with permission.
Date Posted: 03/08/04 nas. Last updated 11/29/04.
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