There is a high degree of spatial and temporal variability in the population of Antarctic krill Euphausia superba across the Scotia Sea. Resolution of the spatial component of this variability requires a 'snapshot' of the krill population over the region (eg the CCAMLR B0 survey) whereas temporal changes have been addressed using time-series of samples from the diet of predators. At South Georgia krill in the diet of Antarctic fur seal Arctocephalus gazella show a good level of concordance with scientific net samples. In order to examine the potential of using krill in the diet of predators to examine both the temporal and spatial variability across the Scotia Sea it is essential to determine the level of concordance at other sites. Samples of krill from South Georgia, the South Orkney Islands and the South Shetland Islands, where predator foraging ranges overlap with intensive krill sampling areas within the CCAMLR B0 survey, will he collected from Antarctic fur sea scats between December and March using a standard methodology. This data will he used to example the level of concordance between krill in the diet or predators and from net hauls, to compare the timing of temporal changes in krill population between sites and to create a basis upon which to assess how the population structure during the CCAMLR B0 survey fits into a longer a longer time frame.
A proposal for large scale sampling of krill in the diet of predators across Area 48 to coincide with the CCAMLR synoptic survey
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WG-EMM-99/33
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