Funding for this research was provided by:
Natural Environment Research Council (NE/M017990/1)
British Antarctic Survey
F. Livermore Trust
Woods Hole Oceanographic Institution emritus fund
Received: 9 October 2017
Accepted: 26 February 2018
First Online: 7 March 2018
Ethics approval and consent to participate
: All fieldwork conformed to international guidelines for the care and use of animals and was carried out under permit from the Government of South Georgia and the South Sandwich Islands.
: Not applicable.
: The authors declare that they have no competing interests.
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