Local weather and body condition influence habitat use and movements on land of molting female southern elephant seals ( Mirounga leonina )

• Published in: Ecology and Evolution
• Main Authors: Chaise, Laureline, Prinet, Iris, Toscani, Camille, Gallon, Susan, Paterson, William, Mccafferty, Dominic, Théry, Marc, Ancel, André, Gilbert, Caroline
• Other Authors: Mécanismes Adaptatifs et Evolution (MECADEV), Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), École nationale vétérinaire - Alfort (ENVA), Scottish Centre for Ecology and the Natural Environment University of Glasgow, Scottish Oceans Institute, University of St Andrews Scotland, DACE, University of Glasgow, Département Ecologie, Physiologie et Ethologie (DEPE-IPHC), Institut Pluridisciplinaire Hubert Curien (IPHC), Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2018
• Subjects: body mass; GPS loggers; habitat selection; marine mammals; meteorological conditions; molt; pinnipeds; population counts; [SDE]Environmental Sciences; Indian; Kerguelen; Wallows; Elephant Seals; Mirounga leonina; Southern Elephant Seals
• Online Access: https://hal.science/hal-01844121; https://doi.org/10.1002/ece3.4049

International audience Southern elephant seals (Mirounga leonina) are known to move and aggregate whilemolting, but little is known about their behavior on land during this time. In this study,60 adult females were monitored (23 with GPS tags) during four molting seasons,between 2012 and 2016 at Kerguelen Archipelago, Indian Ocean. Population surveyswere recorded each year (N = 230 daily counts), and habitat use was analyzed in relationto the stage of the molt and local weather. Based on stage of molt, habitat use,and movements on land, we classified the molt of elephant seals into three phases: (1)a “search phase” at the initial stage of molt when grass and wallow habitats were usedand characterized by greater mean distances travelled on land per day comparedwith the two other phases; (2) a “resident phase”: during initial and mid-stageof moltwhen animals were found in grass and wallow habitats but with less distance movedon land; and (3) a “termination phase” at the final stage of molt where grass and beachhabitats were occupied with no change in distances. Windchill and solar radiationinfluenced individual distances moved per day (mean 590 ± 237.0 m) at the mid-andfinal stage of molt such that animals travelled greater distances on days of low windchillor high solar radiation. Individual variation in distance moved and relative habitatuse were also linked to body mass index (BMI) at arrival on the colony, as femaleswith higher BMI moved less and preferred beach habitat. Moreover, the individualrate of molt increased with the use of wallows. Aggregation rate tended to be negativelycorrelated with distances moved. We therefore suggest that individuals face anenergetic trade-off while molting, balancing energy expenditure between movementand thermoregulation.