The distribution of spatial management and Antarctic krill catch across pelagic bioregions in the Southern Ocean

We have developed a Geographic Information System (GIS) and accompanying metadata to provide standardised and accessible information on the location and extent of spatial fisheries management measures in the Southern Ocean.  We used the GIS in combination with catch data and the results of the 2007 CCAMLR bioregionalisation exercise to examine the relative spatial distribution of fishing activities, existing management, and ecological characteristics. Such analysis is a necessary part of systematic conservation planning for developing marine spatial protection. Our analysis of catch data focused on the Antarctic krill fishery, which accounted for 92% of catch biomass in the Southern Ocean in 2010/11 (CCAMLR Statistical Bulletin, 2012). 64% of the area managed by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) was open to directed fishing for at least one species during the 2010/11 season. However, catch limits were unevenly distributed within this open area due to regional differences in the occurrence of target species and level of fishing interest. There were important differences between pelagic bioregions in terms of the fraction of the bioregion that was open to fishing, and the distribution of catch within the open fraction. For example, 94% of the Antarctic shelf slope bioregion was open to directed fishing for toothfish compared to 32% of the Weddell Gyre & Ross Sea Banks bioregion. Only 26% of the total area open to krill fishing has ever been fished, and this fishing is concentrated in 3 of the 7 bioregions found in the open area. Information on the distribution of catches and catch limits among different bioregions could be used to prioritise protection for bioregions that are currently under-represented in marine protected areas (MPAs), or fished to a proportionally greater extent than other bioregions. However, systematic conservation planning should take appropriate account of uncertainties including those relating to scales of correspondence between datasets. Further development of the spatial management GIS could assist CCAMLR in many of its functions relating to fisheries and ecosystems research, monitoring and management (see also WG-EMM-12-XXX, Secretariat paper on development and management of the database).