Dataset Information

Thermoregulatory costs in molting Antarctic Weddell seals: impacts of physiological and environmental conditions: Themed Issue Article: Conservation of Southern Hemisphere Mammals in a Changing World.

ABSTRACT: For polar marine mammals, the energetic cost of thermoregulation depends on ambient conditions in the highly variable surrounding environment. Heat conservation strategies used by pinnipeds to reduce total heat loss include small surface area to volume ratios, the ability to limit perfusion and thick subcutaneous blubber layers. There are limits to how cool the skin surface may remain without compromising function, especially during the annual pelage molt, when hair and skin are replaced. To determine if actively molting seals incur higher thermoregulatory costs, surface temperature (ST) and heat flux (HF) were measured in 93 adult female Weddell seals (Leptonychotes weddellii) both prior to and during the active molting period using direct sensors and infrared imaging. Linear mixed-effect models revealed that ST increased significantly with increased ambient temperature and decreased wind speed (contributing 44.6 and 41.7% of the attributed variance, respectively). Seal STs were not impacted by molt status, but were maintained at 11.2?±?0.3°C warmer than the ambient temperature. Infrared imaging results averaged 15.1?±?1.4°C warmer than direct ST measurements. In contrast, HF was significantly higher in seals in early molting stages compared to the pre-molt season ( P?

SUBMITTER: Walcott SM

PROVIDER: S-EPMC7125049 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Thermoregulatory costs in molting Antarctic Weddell seals: impacts of physiological and environmental conditions: Themed Issue Article: Conservation of Southern Hemisphere Mammals in a Changing World.

Walcott Skyla M SM Kirkham Amy L AL Burns Jennifer M JM

Conservation physiology 20200404 1

For polar marine mammals, the energetic cost of thermoregulation depends on ambient conditions in the highly variable surrounding environment. Heat conservation strategies used by pinnipeds to reduce total heat loss include small surface area to volume ratios, the ability to limit perfusion and thick subcutaneous blubber layers. There are limits to how cool the skin surface may remain without compromising function, especially during the annual pelage molt, when hair and skin are replaced. To det ...[more]

PMID: 32274067

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Dataset Information

Thermoregulatory costs in molting Antarctic Weddell seals: impacts of physiological and environmental conditions: Themed Issue Article: Conservation of Southern Hemisphere Mammals in a Changing World.

Publications

Thermoregulatory costs in molting Antarctic Weddell seals: impacts of physiological and environmental conditions: Themed Issue Article: Conservation of Southern Hemisphere Mammals in a Changing World.

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