Detailed Record



Thermal acclimation in a non-migratory songbird occurs via changes to thermogenic capacity, but not conductance


Abstract Thermoregulatory performance can be modified through changes in various subordinate traits, but the rate and magnitude of change in these traits is poorly understood. We investigated flexibility in traits that affect thermal balance between black-capped chickadees (Poecile atricapillus) acclimated for 6 weeks to cold (-5°C) or control (23°C) environments (n=7 per treatment). We made repeated measurements of basal and summit metabolic rates via flow-through respirometry and of body composition using quantitative magnetic resonance of live birds. At the end of the acclimation period, we measured thermal conductance of the combined feathers and skins. Cold-acclimated birds had a higher summit metabolic rate, reflecting a greater capacity for endogenous heat generation, and an increased lean mass. However, birds did not alter their thermal conductance. These results suggest that chickadees respond to cold stress by increasing their capacity for heat production rather than increasing heat retention, an energetically expensive strategy.
Authors Rena M. Schweizer ORCID , Abimael Romero , Bret W. Tobalske ORCID , Georgy Semenov ORCID , Matt D. Carling University of Wyoming , Amber M. Rice , Scott A. Taylor ORCID , Zachary A. Cheviron ORCID
Journal Info The Company of Biologists | Journal of Experimental Biology , vol: 226 , iss: 19
Publication Date 10/1/2023
ISSN 0022-0949
TypeKeyword Image article
Open Access hybrid Hybrid Access
DOI https://doi.org/10.1242/jeb.245208
KeywordsKeyword Image Adaptive Evolution (Score: 0.500291)