Author/Authors :
Hewitt، نويسنده , , Roger P. and Watkins، نويسنده , , Jon and Naganobu، نويسنده , , Mikio and Sushin، نويسنده , , Viacheslav and Brierley، نويسنده , , Andrew S. and Demer، نويسنده , , David and Kasatkina، نويسنده , , Svetlana and Takao، نويسنده , , Yoshimi and Goss، نويسنده , , Cathy and Malyshko، نويسنده , , Alexander and Brandon، نويسنده , , Mark and Kawaguchi، نويسنده , , So and Siegel، نويسنده , , Volker، نويسنده ,
Abstract :
In January and February 2000, a collaborative survey designed to assess the biomass of Antarctic krill across the Scotia Sea was conducted aboard research vessels from Japan, Russia, the UK and the USA using active acoustic and net sampling. Survey design, sampling protocols, and data analysis procedures are described. Mean krill density across the survey area was estimated to be 21.4 g m−2, and total biomass was estimated to be 44.3 million tonnes (CV 11.4%). This biomass estimate leads to a revised estimate of precautionary yield for krill in the Scotia Sea of 4 million tonnes. However, before the fishery can be permitted to expand to this level, it will be necessary to establish mechanisms to avoid concentration of fishing effort, particularly near colonies of land-breeding krill predators, and to consider the effects of krill immigrating into the region from multiple sources.
