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Marine megafauna species are affected by a wide range of anthropogenic threats. To evaluate the risk of such threats, species’ vulnerability to each threat must first be determined. We build on the existing threats classification scheme and ranking system of the International Union for Conservation of Nature (IUCN) Red List of Threatened Species by assessing the vulnerability of 256 marine megafauna species to 23 at‐sea threat...
Seasonal occurrence and condition of leopard seals at an extralimital Sub-Antarctic IslandNARA Subscribed
Leopard seals ( Hydrurga leptonyx ) occur mainly south of the Antarctic Polar Front, but immatures, in particular, seasonally move beyond this range during the austral winter and spring, typically under increased sea ice conditions. Extralimital occurrences of leopard seals can be observed at several sub-Antarctic islands where they haul out to rest. We present new records of leopard seal sightings at Marion Island, southern I...
Scaling up ocean conservation through recognition of key biodiversity areas in the Southern Ocean from multispecies tracking dataNARA Subscribed
Biodiversity is critical for maintaining ecosystem function but is threatened by increasing anthropogenic pressures. In the Southern Ocean, a highly biologically productive region containing many endemic species, proactive management is urgently needed to mitigate increasing pressures from fishing, climate change, and tourism. Site‐based conservation is one important tool for managing the negative impacts of human activities o...
We consider how the ongoing recovery of baleen whale populations requires improved understanding when managing the largest commercial fishery in the Southern Ocean, the fishery for Antarctic krill. Baleen whales already represent one of the major consumers of krill, and as such compete with the fishery. However, they are not explicitly included either in the monitoring programme or the krill fisheries management approach of th...
Tracking the foraging migrations of Marion Island southern elephant seals ( Mirounga leonina ) during their first year of lifeNARA Subscribed
The first year of life is critical for large mammals to acquire foraging and predator avoidance skills. Southern elephant seal ( Mirounga leonina ) pups wean at approximately three weeks of age and depart on their first foraging trips in midsummer, typically remaining at sea for three to four months before returning to their natal islands. We describe the foraging trips ( n = 29) of 16 underyearling southern elephant seals fro...
Climate and human stressors on global penguin hotspots: Current assessments for future conservationNARA Subscribed
As charismatic and iconic species, penguins can act as “ambassadors” or flagship species to promote the conservation of marine habitats in the Southern Hemisphere. Unfortunately, there is a lack of reliable, comprehensive, and systematic analysis aimed at compiling spatially explicit assessments of the multiple impacts that the world's 18 species of penguin are facing. We provide such an assessment by combining the available p...
In Antarctica, abundant consumers rely on Antarctic krill for food, but krill are also the subject of a commercial fishery. The fishery overlaps in time and space with the foraging areas of these consumers, thus potential competition between krill fisheries and krill consumers is a major management concern. The fishery is managed by the Commission for the Conservation of Antarctic Marine Living Resources with an ecosystem appr...
Trend changes in sympatric Subantarctic and Antarctic fur seal pup populations at Marion Island, Southern OceanNARA Subscribed
Recent pup population estimates of sympatric Subantarctic ( Arctocephalus tropicalis ) and Antarctic fur seals ( A. gazella ) at Marion Island are presented. Published pup population estimates of A. tropicalis (1995 and 2004) with an unpublished total island count in 2013, and annual counts on subsets of rookeries (2007–2015) were analyzed using a hierarchical Bayesian model. The pup population declined by 46% (95% credible in...
Population genomics of the killer whale indicates ecotype evolution in sympatry involving both selection and driftNARA Subscribed
The evolution of diversity in the marine ecosystem is poorly understood, given the relatively high potential for connectivity, especially for highly mobile species such as whales and dolphins. The killer whale ( Orcinus orca ) has a worldwide distribution, and individual social groups travel over a wide geographic range. Even so, regional populations have been shown to be genetically differentiated, including among different f...
Long distance breeding dispersal of a southern elephant sealNARA Subscribed
Antarctic fur seal predation on cephalopods at Marion IslandNARA Subscribed