Adélie penguins of King George Island depend on resources in CCAMLR Subarea 48.1 in summer, but Subareas 48.5 and 48.2 in winter

Twenty-one individuals of Adélie penguins were tagged with geolocators during the first week of January 2021 in Ardley Island, a CEMP site located in the Fildes Peninusla, southwest of King George Island in Western Antarctica. Eleven GLS were subsequently recovered during December 2021 (52% recovery rate). Two daily locations for each individual track were calculated using the probabilistic algorithm implemented in “probGLS” R package. Three distinct spatial aggregations may be inferred from our observations: 1) a post-reproductive and moulting stage in March-May; 2) a wintering stage in June-September; and 3) a breeding stage in November-January. During the breeding stage, penguins exploited resources available in subarea 48.1, while they depended on resources available in the subarea 48.5 for the post-breeding and moulting stage, and resources distributed across subareas 48.1, 48.2 and 48.5 during wintering. This has two main implications for current debates on conservation measures in area 48. First, it highlights the dependence of Adélie penguins on resources widely distributed across the region to fulfill their yearly cycle, and hence the need for integrated management across 3 different subareas. Second, these results also highlight the relevance of accounting for connectivity when designing and managing MPAs, and hence the relevance of network-level considerations when designing and managing individual MPAs. With an increasing pressure on Adélie penguin colonies in the western Antarctic Peninsula coming from a range of sources, long-term protection of Adélie penguins in the area might depend on well designed and managed MPAs both in the Domain 1 and the Weddell Sea.