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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.
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This content will become publicly available on April 10, 2026
Arduino allows development of a low-cost, high-resolution metabolic and behavioral phenotyping system for birds
Technological advancements now enable the use of flow-through respirometry for rapid, high-throughput metabolic phenotyping, though live-in systems currently do not exist for birds. We designed live-in respirometry chambers for small birds with an Arduino-based electronic system to continuously monitor bird body weight, food intake, and water intake in sync with metabolic data collection. To demonstrate how this system can be implemented, we kept birds in the metabolic phenotypic chambers for 10 days while we progressively lowered the temperature from 25 °C to 5 °C. We used the data to calculate hourly energy expenditure and food/water intake during acute cold acclimation. We provide all plans and code for the live-in chambers, Arduino biomonitoring system, and additional RFID module as a low-cost, DIY alternative to commercially available systems and to enable the use of standard respirometry equipment for metabolic phenotyping in birds.
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- Award ID(s):
- 1941475
- PAR ID:
- 10586125
- Publisher / Repository:
- Journal of Experimental Biology
- Date Published:
- Journal Name:
- Journal of Experimental Biology
- ISSN:
- 0022-0949
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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