Summer foraging hot spots of post-breeding southern elephant seal males from King George Island / Isla 25 de Mayo

Deployments of ARGOS satellite transmitters on 19 post-breeding adult southern elephant seal males at King George Island / Isla 25 de Mayo in November 2013 represent a follow-up study of earlier projects on post-moulting adult males satellite tagged in 2000 and 2010. These previous deployments were...

Full description

Bibliographic Details
Main Authors: Bornemann, Horst, Márquez, M. E. I., Mennucci, J. A., Daneri, G. A., Bester, M. N., Rogers, T., Eisert, R., Dorschel, Boris, Hellmer, Hartmut, Schröder, Michael
Format: Conference Object
Language:unknown
Published: 2014
Subjects:
Online Access:https://epic.awi.de/id/eprint/36605/
https://epic.awi.de/id/eprint/36605/1/Bornemann-etal_SCAR_2014.pdf
https://hdl.handle.net/10013/epic.44408
https://hdl.handle.net/10013/epic.44408.d001
Description
Summary:Deployments of ARGOS satellite transmitters on 19 post-breeding adult southern elephant seal males at King George Island / Isla 25 de Mayo in November 2013 represent a follow-up study of earlier projects on post-moulting adult males satellite tagged in 2000 and 2010. These previous deployments were constrained by the fact that only a small fraction of the satellite tagged seals could be unequivocally attributed to the local breeding population of the Antarctic Specially Protected Area (ASPA) 132 on King George Island / Isla 25 de Mayo due to earlier permanent marking procedures. As a result, a number of the previous tracks ended at South Georgia towards the breeding season, implying that the tagged seals originated from that breeding colony. The recent tracks represent the first deployments on post-breeding males at the ASPA 132 and they include about 50% of the population of adult males that were present during the breeding period either as harem bulls (n = 3), challengers (n = 7), or isolated males (n = 9) between October and December 2013. Of the 19 transmitters, two failed within the first two weeks after deployment and were disregarded for further analyses. The post-breeding long-distance foraging tracks of the remaining 17 males were primarily oriented along the continental shelf margin towards the Bellingshausen and even Amundsen Seas (n = 12), and shorter tracks along the Bransfield Strait / Mar de la Flota to the North (n = 4) and around the tip of the Antarctic Peninsula (n = 1). This suggests far more south-westerly oriented foraging movements of mature males of the ASPA 132 elephant seal colony than previously assumed. All seals showed extended residence times at specific circumscribed at-sea locations, considered as foraging hot spots. These spots were widely distributed within the aforementioned marine areas and coincide with bathymetric features, such as slopes, bays and troughs.