A fishy business around South Georgia

9 March, 2017

In this blog Dr Mark Belchier from British Antarctic Survey (BAS) explains why a team of experts visits King Edward Point biennially to carry out a survey of the fish that inhabit the sea around South Georgia.

Every two years BAS leads a scientific research survey of the fish resources on behalf of the Government of South Georgia and South Sandwich Islands. This year a team of seven people including four BAS ecologists (me, Sue Gregory, Simeon Hill  and Vicki Foster), were accompanied by a colleague from CEFAS (Vlad Laptikhovsky), a CCAMLR international observer (Pete Lafitte, from South Africa) and UK fishing captain (Len Featherstone).

Nets prepared for catching fish around South Georgia

The 2017 survey was conducted from a commercial fishing vessel over 12 days in January and February. Trawls were carried out all around the island of South Georgia and Shag Rocks and at each location the size, composition and biological characteristics of the fish we caught were sampled and recorded. These data will  form the basis upon which sustainable catch limits for the mackerel icefish are set for the following season at the annual meeting of CCAMLR in October in Hobart. In addition to information on the size of the mackerel icefish stock, the survey also provides new data on the abundance of juvenile Patagonian toothfish and a wide range of other fish species such as the marbled rock cod which was over-fished in the 1970s, but is thought to be slowly  recovering at South Georgia following a total ban on fishing 30 years ago.

Dr Mark Belchier holds a Patagonian toothfish

In addition to assessing changes in the composition and abundance of fish populations over time, the survey is also used to collect samples for a range of scientific collaborations between BAS and international partners. These include food web and molecular studies and monitoring microplastics in the marine environment. The survey team also deployed HD cameras on the trawl net in order to provide data on both fish behaviour and habitat type. Hours of analysis of video footage await the returning science team!

The team relaxing after a long day’s work at sea