Translator Disclaimer
1 February 2008 Previous Experience and Reproductive Investment of Female Columbian Ground Squirrels
David R. Broussard, F. Stephen Dobson, J. O. Murie
Author Affiliations +
Abstract

Reproductive success of females in iteroparous species usually increases early in life, then remains constant or declines. The restraint hypothesis suggests that primiparous females limit their 1st reproduction in order to avoid future costs to survival, reproduction, or both, whereas constraint indicates that primiparous females are limited in their 1st reproductive attempt either because they lack sufficient resources (measured by body mass) or lack experience at weaning a litter. To evaluate these alternatives, we examined age- and experience-related patterns of reproduction in female Columbian ground squirrels (Spermophilus columbianus) with data from a long-term study and by experimentally altering age at 1st reproduction. In the results of the long-term study, experienced females had significantly higher reproductive investment and reproductive success (number of offspring surviving to yearling age) compared to inexperienced females. Annual survival of females was not affected by their level of previous weaning experience or current reproductive investment. Additionally, subsequent reproductive success was not impaired by earlier reproduction. In the experimental results, experienced females had significantly higher reproductive investments compared to inexperienced females. Constraint in terms of previous weaning experience best explained the differences in reproductive investment and reproductive success between primiparous and multiparous females.

David R. Broussard, F. Stephen Dobson, and J. O. Murie "Previous Experience and Reproductive Investment of Female Columbian Ground Squirrels," Journal of Mammalogy 89(1), 145-152, (1 February 2008). https://doi.org/10.1644/06-MAMM-A-357.1
Accepted: 1 May 2007; Published: 1 February 2008
JOURNAL ARTICLE
8 PAGES


Share
SHARE
KEYWORDS
constraint
experience
Reproductive investment
reproductive success
restraint
Spermophilus columbianus
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top