University of Southampton investigates Antarctic krill sustainability

This journey, which began a couple of weeks ago, is utilising a yacht as a mode of transport to reach the isolated peninsula in an effort to tag the whales and carry out a survey on krill, their primary source of food.

Both the whales and the krill play crucial roles in the Southern Ocean ecosystem, and their study could provide valuable data in evaluating the effectiveness of the fishery management framework in safeguarding the krill population.

Antarctic krill caught during net tows to understand the sizes of individual krill that make up the krill swarms observed using an echo sounder aboard the boat (Image: Ryan Reisinger)

Dr Ryan Reisinger from the University of Southampton, who is leading the expedition, said: "The risk is that fishing becomes concentrated in krill-rich predator feeding spots and then depletes them, leaving nothing behind for the marine animals that rely on them to survive."

Krill are one of the earth's most plentiful animals, being the main food for a variety of predators including fish, penguins, seals, and whales.

They are increasingly being caught for commercial fishing, used for fish farms, and turned into oils for nutritional supplements.

The population of baleen whales was once close to extinction but is now reviving and they find themselves competing with fishing vessels.

The researchers from the University of Southampton, in co-ordination with other international organisations, aim to collect information that aims to understand the distribution of foraging fin whales, Antarctic krill, and fishing boats.

A fin whale surfaces in front of an iceberg in King George Bay, South Shetland Islands, Antarctica (Image: Ryan Reisinger)

The team is fitting the fin whales with tags that provide short-term and long-term information about the whales, and using echo sounders to locate krill swarms.

Dr Reisinger added: "Tagging whales helps us to understand in far greater detail where and how whales feed on krill, information that is essential for us to manage and conserve Southern Ocean ecosystems. We know surprisingly little about how the largest whales - including fin whales - behave in Antarctica."

All information gathered from this expedition, along with fishing vessel activity data provided by the CCAMLR and Global Fishing Watch, will be combined to model interactions between krill, whales, and fisheries.

This will assist in providing forecasts for more precise, dynamic, fisheries management.