Antarctic krill and ecosystem monitoring survey off the South Orkney Islands in 2023

Abstract

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 body-size of individual whales to form the basis for calculating energetics and prey needs. Personnel were also deployed on Powell Island with breeding chinstrap penguins to satellite-tag penguins. At the same time, we maneuvered an unmanned sail drone, fitted with an echosounder, via satellite communication into what is known to be the preferred feeding area for chinstraps that breed at Powell Island. This data will be used to study swarm types in relation to penguins foraging strategies as well as assessing potential spatiotemporal overlaps with fisheries. Herein we report on the survey activities from 2023 and present some preliminary results.

Antarctic krill and ecosystem monitoring survey off the South Orkney Islands in 2023