South Shetland Island fur seals: conservation status and distribution updates

As an apex krill-dependent predator, Antarctic fur seals (Arctocephalus gazella, AFS) are a key indicator species for the CCAMLR Ecosystem Monitoring Programme (CEMP). The prevailing conservation paradigm for AFS is a circumpolar, panmictic, stable population; however, a suite of recent research concludes that there are at least four strongly genetically-differentiated subpopulations including one in the South Shetland Islands (SSI). The SSI population of AFS is experiencing a rapid, potentially catastrophic decline in abundance. Understanding the post-breeding dispersal of marine predators, especially young of the year, is crucial for understanding their ecology and for informing potential management decisions.  Here we update the population status and a metric of foraging habitat quality for SSI AFS with data from the 2021-22 field season at Cape Shirreff. We also summarize the post-weaning dispersal and habitat use of SSI AFS pups over four austral winters between 2005-2019. SSI AFS harbor a disproportionately large reservoir of genetic diversity for the species, such diversity is worth conserving if decision makers wish to promote resilience and support the future recolonization potential of this species. The risks associated with the spatial and temporal overlap between the pups of this vulnerable subpopulation and the krill fishery should be considered carefully.