Antarctic Krill, Euphausia superba, is the key species of the Southern Ocean ecosystem. Earlier analysis suggested decrease in krill abundance by 50% since the mid 1970’s to early 2000’s in the Southwest Atlantic Sector, which has been specifically linked to a decrease in extent and duration of sea-ice coverage. More recent studies suggest more complex and/or dynamic nature of krill population trajectory as well as its link with decadal climatic events.
Krill population dynamics is thought to be strongly linked to sea ice, and their reproductive output and recruitment success been related to extent, timing and the duration of winter sea ice cover. The underside structures of sea ice are generally thought to provide good feeding ground as well as nursery grounds for overwintering larvae.
How will changing sea ice dynamics affect krill life history, their dynamics, and their distribution? This is a fundamental question for designing our future management approach for the krill fishery.
The intention of this paper is to provide the Working Group with a summary of our recent efforts published last year to improve the mechanistic understanding of the interaction between krill larvae and sea ice (WG-EMM-18/P04 and P05).