Environmental influences on the at-sea behaviour of a major consumer, Mirounga leonina, in a rapidly changing environment

Polar Research

Horst Bornemann¹  Daniel Steinhage¹  Trevor McIntyre¹  Joachim Plötz¹  Maria E.I. Márquez²  Marthán N. Bester³  Ryan R. Reisinger³  P.J. Nico de Bruyn³ 

[1] Alfred-Wegener-Institut Helmholtz-Zentrum für Polar-und Meeresforschung, Postfach 120161, DE-27515, Bremerhaven, Germany;Instituto Antártico Argentino, Departamento Biologia de Predadores Tope, Balcarce 290 (C1064AAF), Buenos Aires, Argentina;Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, 0028, South Africa;

关键词: Southern elephant seals;    foraging ecology;    satellite-relay data loggers;    King George Island;    Isla 25 de Mayo;    at-sea behaviour;   

DOI  :  10.3402/polar.v33.23808

来源: DOAJ

【 摘 要 】

Understanding the distribution and foraging ecology of major consumers within pelagic systems, specifically in relation to physical parameters, can be important for the management of bentho-pelagic systems undergoing rapid change associated with global climate change and other anthropogenic disturbances such as fishing (i.e., the Antarctic Peninsula and Scotia Sea). We tracked 11 adult male southern elephant seals (Mirounga leonina), during their five-month post-moult foraging migrations from King George Island (Isla 25 de Mayo), northern Antarctic Peninsula, using tags capable of recording and transmitting behavioural data and in situ temperature and salinity data. Seals foraged mostly within the Weddell–Scotia Confluence, while a few foraged along the western Antarctic Peninsula shelf of the Bellingshausen Sea. Mixed model outputs suggest that the at-sea behaviour of seals was associated with a number of environmental parameters, especially seafloor depth, sea-ice concentrations and the temperature structure of the water column. Seals increased dive bottom times and travelled at slower speeds in shallower areas and areas with increased sea-ice concentrations. Changes in dive depth and durations, as well as relative amount of time spent during the bottom phases of dives, were observed in relation to differences in overall temperature gradient, likely as a response to vertical changes in prey distribution associated with temperature stratification in the water column. Our results illustrate the likely complex influences of bathymetry, hydrography and sea ice on the behaviour of male southern elephant seals in a changing environment and highlight the need for region-specific approaches to studying environmental influences on behaviour.

【 授权许可】

Unknown