Huddling behavior in emperor penguins : dynamics of huddling

• Main Authors: Gilbert, C., Robertson, G., Le Maho, Y., Naito, Y., Ancel, A.
• Other Authors: Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Australian Antarctic Division (AAD), Australian Government, Department of the Environment and Energy, National Insitute of Polar Research, National Institute of Polar Research Tokyo (NiPR)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2006
• Subjects: Animals; Antarctic Regions; Circadian Rhythm; Climate; Feeding Behavior; Female; Individuality; Light; Male; Research Support; Non-U.S. Gov't; Sex Behavior; Animal; Social Behavior Spheniscidae/*physiology Temperature Weather; [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE]; Antarctic; The Antarctic; Antarc*; Aptenodytes forsteri; Emperor penguins
• Online Access: https://hal.science/hal-00127765; https://hal.science/hal-00127765/document; https://hal.science/hal-00127765/file/Gilbert_Hudling.pdf; https://doi.org/10.1016/j.physbeth.2006.04.024

International audience Although huddling was shown to be the key by which emperor penguins (Aptenodytes forsteri) save energy and sustain their breeding fast during the Antarctic winter, the intricacies of this social behavior have been poorly studied. We recorded abiotic variables with data loggers glued to the feathers of eight individually marked emperor penguins to investigate their thermoregulatory behavior and to estimate their "huddling time budget" throughout the breeding season (pairing and incubation period). Contrary to the classic view, huddling episodes were discontinuous and of short and variable duration, lasting 1.6+/-1.7 (S.D.) h on average. Despite heterogeneous huddling groups, birds had equal access to the warmth of the huddles. Throughout the breeding season, males huddled for 38+/-18% (S.D.) of their time, which raised the ambient temperature that birds were exposed to above 0 degrees C (at average external temperatures of -17 degrees C). As a consequence of tight huddles, ambient temperatures were above 20 degrees C during 13+/-12% (S.D.) of their huddling time. Ambient temperatures increased up to 37.5 degrees C, close to birds' body temperature. This complex social behavior therefore enables all breeders to get a regular and equal access to an environment which allows them to save energy and successfully incubate their eggs during the Antarctic winter.