Meeting Abstract

54.2  Tuesday, Jan. 6  Intra-specific variation in the metabolic rate of the red squirrel (Tamiasciurus hudsonicus) across western Canada BEN-EZRA, E.*; HUMPHRIES, M.M; McGill University; McGill University elad.ben-ezra@mail.mcgill.ca

Metabolic rate is a fundamental trait that determines the amount of energy an organism can process and allocate to growth, maintenance, and reproduction. While metabolic rate is known to scale with mass, there is a significant amount of residual inter- and intra-specific variation that can be partially explained by differences in climate, temperature, and habitat. Latitudinal gradients in intra-specific metabolism incorporate large variation in many of these factors and reveal how the physiological ecology of local populations varies within a species’ range. We examined variation in the metabolic rate of the North American red squirrel, Tamiasciurus hudsonicus, by sampling individuals from seven populations along a latitudinal gradient in western Canada, spanning over 3000 km from northern Yukon to southern Alberta. We found that whole-body metabolic rate increased with latitude, while no relationship existed between latitude and mass-specific metabolic rate. This study is the first to examine large-scale intra-specific variation in the metabolic rate of a small mammal.