Squid in the diet of Antarctic fur seals: potential links to oceanographic conditions and Antarctic krill abundance

2019 ◽  
Vol 628 ◽  
pp. 211-221 ◽  
Author(s):  
J Abreu ◽  
I Staniland ◽  
CF Rodrigues ◽  
JP Queirós ◽  
JM Pereira ◽  
...  
Keyword(s):  
Antarctic Krill ◽  
Krill Abundance ◽  
Fur Seals ◽  
Oceanographic Conditions ◽  
Antarctic Fur Seals

scholarly journals Winter distribution of juvenile and sub-adult male Antarctic fur seals (Arctocephalus gazella) along the western Antarctic Peninsula

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
David March ◽  
Massimiliano Drago ◽  
Manel Gazo ◽  
Mariluz Parga ◽  
Diego Rita ◽  
...  
Keyword(s):  
Antarctic Peninsula ◽  
Adult Male ◽  
Antarctic Krill ◽  
South Shetland Islands ◽  
Distribution Area ◽  
Arctocephalus Gazella ◽  
Western Antarctic Peninsula ◽  
Adult Males ◽  
Fur Seals ◽  
Antarctic Fur Seals

AbstractDetailed knowledge of habitat use by marine megafauna is critical to understand their ecological roles and for the adequate management of marine resources. Antarctic fur seals (Arctocephalus gazella) inhabiting the Atlantic sector of the Southern Ocean prey largely on Antarctic krill (Euphausia superba) and play a central role in managing the krill fishery. Here, we assessed the demographic structure of three post-mating, early moult male haul-outs in the South Shetland Islands in early March and calculated the relative contribution of juveniles (1–4 years old) and sub-adult males (5–6 years) to the population remaining in maritime Antarctica after the breeding season. We also satellite tagged 11 juvenile males and four sub-adult males to analyze their movements and develop a species distribution model including both age classes. Our results highlighted the dominance of young individuals in the male population, revealed that they do not behave as central place foragers and identified key environmental drivers that affected their distribution at-sea throughout winter. Predicted potential foraging habitat overlapped highly with the known distribution of Antarctic krill, and identified the waters off the western Antarctic Peninsula and the Scotia Sea as the core of the distribution area of juvenile and sub-adult male Antarctic fur seals in winter. This pattern is similar to that of adult males but totally different from that of adult females, as the latter overwinter in areas at latitude 45–55° S. This segregation has implications for the ecology and management of the krill fishery.

scholarly journals Male Antarctic fur seals: neglected food competitors of bioindicator species in the context of an increasing Antarctic krill fishery

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
A. D. Lowther ◽  
I. Staniland ◽  
C. Lydersen ◽  
K. M. Kovacs
Keyword(s):  
Antarctic Krill ◽  
Marine Protected Area ◽  
Monitoring Program ◽  
Fishing Effort ◽  
Bioindicator Species ◽  
Ecosystem Monitoring ◽  
Holistic View ◽  
Fur Seals ◽  
Antarctic Fur Seals

Abstract The fishery for Antarctic krill is currently managed using a precautionary, ecosystem-based approach to limiting catch, with performance indices from a long-term monitoring program focused on several krill-dependent predators that are used to track ecosystem health. Concerns over increased fishing in concentrated areas and ongoing efforts to establish a Marine Protected Area along the Peninsula, a key fishing region, is driving the development of an adaptive management system for the fishery. The cumulative effects of fishing effort and interactions among krill-dependent predators and their performance is at present neglected in the CCAMLR Ecosystem Monitoring Program. However, we show considerable overlap between male Antarctic fur seals and the krill fishery in a complex mosaic, suggesting potential for cumulative impacts on other krill dependent predators. A holistic view is required as part of future efforts to manage the krill fishery that incorporates various sources of potential impacts on the performance of bioindicator species, including the fishery and its interactions with various krill dependent predators.

scholarly journals Wintertime overlaps between female Antarctic fur seals (Arctocephalus gazella) and the krill fishery at South Georgia, South Atlantic

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248071
Author(s):  
Connor C. G. Bamford ◽  
Victoria Warwick-Evans ◽  
Iain J. Staniland ◽  
Jennifer A. Jackson ◽  
Philip N. Trathan
Keyword(s):  
Antarctic Krill ◽  
Euphausia Superba ◽  
Arctocephalus Gazella ◽  
Habitat Models ◽  
South Georgia ◽  
Fur Seals ◽  
Fur Seal ◽  
Ice Edge ◽  
Future Work ◽  
Antarctic Fur Seals

The diet of Antarctic fur seals (Arctocephalus gazella) at South Georgia is dominated by Antarctic krill (Euphausia superba). During the breeding season, foraging trips by lactating female fur seals are constrained by their need to return to land to provision their pups. Post-breeding, seals disperse in order to feed and recover condition; estimates indicate c.70% of females remain near to South Georgia, whilst others head west towards the Patagonian Shelf or south to the ice-edge. The krill fishery at South Georgia operates only during the winter, providing the potential for fur seal: fishery interaction during these months. Here we use available winter (May to September) tracking data from Platform Terminal Transmitter (PTT) tags deployed on female fur seals at Bird Island, South Georgia. We develop habitat models describing their distribution during the winters of 1999 and 2003 with the aim of visualising and quantifying the degree of spatial overlap between female fur seals and krill harvesting in South Georgia waters. We show that spatial distribution of fur seals around South Georgia is extensive, and that the krill fishery overlaps with small, highly localised areas of available fur seal habitat. From these findings we discuss the implications for management, and future work.

MODELING THE CONSEQUENCES OF ANTARCTIC KRILL HARVESTING ON ANTARCTIC FUR SEALS

2000 ◽  
Vol 10 (6) ◽  
pp. 1806-1819 ◽  
Author(s):  
R. B. Thomson ◽  
D. S. Butterworth ◽  
I. L. Boyd ◽  
J. P. Croxall
Keyword(s):  
Antarctic Krill ◽  
Fur Seals ◽  
Antarctic Fur Seals

Fur seals, whales and tourists: a commercial history of Deception Island, Antarctica

Polar Record ◽  
2009 ◽  
Vol 46 (3) ◽  
pp. 210-221 ◽  
Author(s):  
J. Stephen Dibbern
Keyword(s):  
South Shetland Islands ◽  
Deception Island ◽  
Commercial Activity ◽  
Early 19Th Century ◽  
Cruise Industry ◽  
Shetland Islands ◽  
Fur Seals ◽  
History Of ◽  
The Antarctic ◽  
Antarctic Fur Seals

ABSTRACTDeception Island in the South Shetland Islands was the site of some of the earliest commercial activity to be carried out in the Antarctic with the early 19th century hunting of Antarctic fur seals. Nearly a century later it was the site of the most extensive anchorage for the reconstructed ships and ocean liners used as non-pelagic whale processing factories. Deception was also the site of what is the only successful land based commercial activity in Antarctic history. The Hektor whaling station operated in Whalers Bay from 1912 until 1931. Most of the remains of the station have now been obliterated by the volcanic activity that occurred in the late 1960s and 1970. By the later part of the twentieth century Deception Island had become a regular stop for the growing Antarctic tourist cruise industry. No other place in Antarctica has been so thoroughly identified with commercial activity.

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