Modelling Movement of Antarctic Krill (MMAK): the importance of retention, dispersal and behaviour for krill distribution – a project update

This paper provides an update on the joint UK-Norway MMAK project, funded by the Antarctic Wildlife Research Fund, to improve current understanding of the regional and local-scale processes that influence the distribution of Antarctic krill in CCAMLR Area 48, focussing in particular on the South Orkney Islands region.  MMAK uses modelling studies at varying spatial and temporal resolutions to investigate the impact of physical and behavioural processes on the distribution of krill in this area, at scales relevant to the krill fishery and predators.  Preliminary analysis of a 20-year time series of simulated transport to the South Orkneys region demonstrates spatial and temporal variability in input and transfer to the wider Scotia Sea.  Results suggest that resolving the interaction of krill with sea ice is critical for determining the pathways and timescales of transport into and out of the region. Links between transport and large-scale climatic indices are now being explored and processes at a finer resolution are being investigated, which will include examination of the role of tides in determining on-shelf retention and transfer.