Report on the annual Norwegian krill survey off the South Orkney Islands, 2023

Environmental monitoring along 5 set transect lines off South Orkney Islands in the Southern Ocean have been carried out annually (since 2011) by the Institute of Marine Research, Norway. Data are used to calculate biomass of Antarctic krill (Euphausia superba) as well as mapping distribution and demographic composition of krill, but also other macrozooplankton and fish taxa. Visual sightings of cetaceans and pinnipeds are registered systematically along the transects during daylight hours. During this year's survey, a pilot photo-drone project was also undertaken to investigate the potential of employing this type of technology to monitor sizes of individual whales which in turn can form the basis for calculating their energetic and prey needs. Personnel were also deployed on Powell Island with breeding chinstrap penguins to satellite tag penguins, to investigate foraging behaviour. At the same time we steered an unmanned sail drone equipped with an echosounder via satellite communication into what is known to be the preferred feeding area for chinstraps breeding at Powell Island. These data will be used to study what swarm types penguins prefer to target and if they influence on swarms structures as well as this information can be used to assess overlap with fisheries. Herein we report on the survey activities from 2023 and present some preliminary result.