Translator Disclaimer
1 March 2001 BUMPUS IN THE SNAKE DEN: EFFECTS OF SEX, SIZE, AND BODY CONDITION ON MORTALITY OF RED-SIDED GARTER SNAKES
Author Affiliations +
Abstract

Huge breeding aggregations of red-sided garter snakes (Thamnophis sirtalis parietalis) at overwintering dens in Manitoba provide a unique opportunity to identify sources of mortality and to clarify factors that influence a snake's vulnerability to these factors. Comparisons of sexes, body sizes, and body condition of more than 1000 dead snakes versus live animals sampled at the same time reveal significant biases. Three primary sources of mortality were identified. Predation by crows, Corvus brachyrhynchos (590 snakes killed), was focussed mostly on small snakes of both sexes. Crows generally removed the snake's liver and left the carcass, but very small snakes were sometimes brought back to the nest. Suffocation beneath massive piles of other snakes within the den (301 dead animals) involved mostly small males and (to a lesser extent) large females; snakes in poor body condition were particularly vulnerable. Many emaciated snakes (n = 142, mostly females) also died without overt injuries, probably due to depleted energy reserves. These biases in vulnerability are readily interpretable from information on behavioral ecology of the snakes. For example, sex biases in mortality reflect differences in postemergence behavior and locomotor capacity, the greater attractiveness of larger females to males, and the high energy costs of reproduction for females.

R. Shine, M. P. LeMaster, I. T. Moore, M. M. Olsson, and R. T. Mason "BUMPUS IN THE SNAKE DEN: EFFECTS OF SEX, SIZE, AND BODY CONDITION ON MORTALITY OF RED-SIDED GARTER SNAKES," Evolution 55(3), 598-604, (1 March 2001). https://doi.org/10.1554/0014-3820(2001)055[0598:BITSDE]2.0.CO;2
Received: 8 August 2000; Accepted: 1 October 2000; Published: 1 March 2001
JOURNAL ARTICLE
7 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top