Thermoregulation in polar seals: Profiling surface heat in Weddell seals

• Published in: The FASEB Journal
• Main Authors: Mellish, Jo‐Ann, Hindle, Allyson, Horning, Markus
• Other Authors: National Science Foundation
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2013
• Subjects: Antarctic; Weddell; Antarc*; Weddell Seals
• Online Access: http://dx.doi.org/10.1096/fasebj.27.1_supplement.lb737

Our understanding of thermoregulation in marine mammals is ambiguous at best, due to the conflicting needs of homeostasis in air and water. Infrared imaging (IRT) has become increasingly applied to wildlife research given the non‐invasive nature of the technology, which is particularly desirable for work with species that are at risk and/or difficult to handle. Our prior work identified species‐specific patterns of heat loss by season and body condition under controlled conditions. As part of a larger study, we are assessing the use of IRT under extreme Antarctic field conditions to determine baseline and variation in thermal profiles in animals of known condition and physiological state. Weddell seals show consistent hot spots around the poorly insulated head and well‐insulated but active axilla. The trunk and neck are typically cool, whereas flippers are variable. Best fit LME showed ambient temperature, relative humidity and blubber depth to be the primary predictors of IRT signatures. Animal, body site and wind speed were not significant. Profiles were similar between wet and dry seals, however, dry animals can have surface temperatures that are only marginally above ambient, greatly minimizing heat loss. Funded by NSF.