Groundfish Survey Unveils Insights on South Georgia Marine Life
The waters surrounding South Georgia, nestled beneath glaciated mountains, are among the most biologically rich in the Southern Ocean. In February, a team of scientists from the British Antarctic Survey (BAS) and international institutions embarked on an important research expedition to explore the diverse marine life – including groundfish – thriving 300 metres below the surface.
Aboard the Polar Seafish Vessel Sil, the team, led by Chief Scientist Professor Martin Collins, conducted a two-week trawl survey funded by the Government of South Georgia and the South Sandwich Islands (GSGSSI). Their mission: to investigate icefish densities and the distribution of young Patagonian toothfish. This research underpins the sustainably managed fishery in the region.
The research trawls revealed significant aggregations of mackerel icefish, key to commercial fisheries, as well as abundant South Georgia and Scotia Sea icefish. These samples are vital for researchers like Huw James, a PhD student at Newcastle University, who will use them to study the life histories and diets of different species.
Despite challenging conditions such as 50-knot winds and 4-metre swells, the team completed more trawls and tagged more Patagonian toothfish than in any survey over the past 20 years. Each tagged fish, marked with a unique number below the dorsal fin, will provide critical data on fish movement and growth when recaptured.
This year’s survey ventured deeper than ever before, thanks to funding from the UK Government’s Blue Belt Programme. New explorations into waters between 400 and 750 meters uncovered unique deep-sea species, including dagger-tooth fishes, king crabs, warty squids, and juvenile skates. Some of these rare specimens will be added to the Natural History Museum’s collection in London.
For the first time, the survey also trialled a Neuston Net, a specially designed tool to capture larval fish at the water’s surface at night. This stage in the life cycle of icefish and toothfish remains poorly understood.
The findings from this year’s Groundfish survey will be presented at the upcoming meeting of the Commission on the Conservation of Antarctic Marine Living Resources (CCAMLR) in Hobart, Australia. The data collected will play a key role in shaping the sustainable management of South Georgia’s fisheries, ensuring the long-term health of these vital marine ecosystems.
https://www.bas.ac.uk/media-post/groundfish-survey-reveals-key-insights-into-south-georgias-marine-life/