Ontogenetic niche partitioning in southern elephant seals from Argentine Patagonia

International audience Elephant seals, Mirounga spp., are highly dimorphic, having different energetic requirements according to age and sex, and foraging in various ecological and oceanographic contexts. Resource partitioning has been shown for the sub‐Antarctic populations of southern elephant sea...

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Bibliographic Details
Published in:Marine Mammal Science
Main Authors: Campagna, Julieta, Lewis, Mirtha, González Carman, Victoria, Campagna, Claudio, Guinet, Christophe, Johnson, Mark, Davis, Randall W., Rodríguez, Diego H., Hindell, Mark
Other Authors: Centro para el Estudio de Sistemas Marinos (CESIMAR/CENPAT-CONICET) (CESIMAR), Instituto Nacional de Investigación y Desarrollo Pesquero (INIDEP), Instituto de Investigaciones Marinas y Costeras Mar del Plata (IIMyC), Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires (CONICET)-Facultad de Ciencias Exactas y Naturales Mar del Plata, Universidad Nacional de Mar del Plata Mar del Plata (UNMdP)-Universidad Nacional de Mar del Plata Mar del Plata (UNMdP), Wildlife Conservation Society Argentina, Marine and Argentina Programs, Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Sea Mammal Research Unit University of St Andrews (SMRU), School of Biology University of St Andrews, University of St Andrews Scotland -University of St Andrews Scotland -Natural Environment Research Council (NERC), Department of Marine Biology, Texas A&M University Texas, USA, Texas A&M University College Station, Institute for Marine and Antarctic Studies and Centre for Marine Socioecology, University of Tasmania Hobart, Australia (UTAS)
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2021
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Online Access:https://hal.science/hal-03138766
https://doi.org/10.1111/mms.12770
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Summary:International audience Elephant seals, Mirounga spp., are highly dimorphic, having different energetic requirements according to age and sex, and foraging in various ecological and oceanographic contexts. Resource partitioning has been shown for the sub‐Antarctic populations of southern elephant seals, M. leonina, where colonies are surrounded by narrow shelves that deepen abruptly. In contrast, seals from Península Valdés (Argentina), in the northernmost extent of the breeding range, face an extended, shallow, temperate, and productive continental shelf. We integrated tracking data from 98 animals (juveniles and adults, males and females) gathered over more than two decades, and found that although all available habitats were used, individuals segregated by age and sex. Juvenile males favored shelf habitats, whereas subadult and adult males also used the shelf break. Juvenile females preferred the shelf and the more distant Argentine Basin used by postbreeding and postmolt adult females. Males showed the highest proportion of area‐restricted search locations, suggesting more spatially concentrated feeding activity, and likely reflecting a preference for foraging habitat and prey. Our results are consistent with those from other populations, implying that elephant seals show remarkable similarities in habitat use by age and sex classes, despite broad differences in the offshore habitats between sub‐Antarctic and temperate ecosystems.