Krill are small shrimp-like crustaceans. There are over 80 species of krill in the oceans but the most well-known and commercially important is Antarctic krill, found in the Southern Ocean near Antarctica.
Antarctic krill can sometimes form super swarms, so big they can be seen from space. With an estimated biomass of around 300 million tonnes in the Southern Ocean, krill are among the most abundant animals on earth.
Why is krill so important?
Krill are vital to the Antarctic food chain and the main source of food for whales, seals, penguins, seabirds, squids and finfishes. They are designated by scientists as ‘keystone’ species. While krill are abundant, without sustainability measures in place, if too many are removed from the ecosystem it could lead to the system’s collapse.
Why do we harvest krill?
Krill is rich in Omega-3 fatty-acids, micronutrients and the antioxidant Astaxanthin. Krill is processed to form oil and is sold as a nutritional supplement for human health products. Krill meal and oil are also used in aquaculture and animal feed.
The market for krill oil is growing and over the past decade krill catch in the Antarctic has been increasing. As such, it is important that krill fishing is informed by science and research and is closely monitored to ensure it is sustainable and well-managed.
How can we be sure that krill is well-managed?
Fishing in the Antarctic is regulated by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR).
CCAMLR was established in 1982 with the objective of conserving Antarctic marine life through conservation and ecosystem-based management and to prevent the unregulated expansion of krill fisheries in the Southern Ocean.
CCAMLR has a legally binding international convention to ensure the conservation of the Antarctic ecosystems. CCAMLR’s 27 members and a further 10 countries have agreed to the convention.
It is widely recognised as leading and developing best practice for fisheries management worldwide. The commission takes a cautious approach to fishery management. Through consensus agreement of all members, krill fishing is only permitted in approximately 10% of Antarctic waters. CCAMLR also sets extremely conservative ‘Trigger Level’ catch limits on krill fisheries.
The Trigger Level is based on the abundance of krill and ensures the estimated needs of their predators i.e., whales, penguins, seals, etc., are met. The catch limit has consistently remained at approximately 1% of the total estimated krill biomass in tightly controlled designated fishing areas. The highest catch to date was 450,781 tonnes in 2020 but all catches have remained well below the limit.
Recent research has found that along with increased fishing, other factors can potentially impact on krill. Rebounding humpback whale populations are consuming more krill, and climate change and the reduction in sea-ice may also have an effect. Together, these factors are thought to affect chinstrap penguins’ ability to feed and breed effectively, leading to a decline in their numbers.
These additional factors make it even more important for krill fisheries to be managed at their current precautionary levels, with catch kept low.
Since 2020 CCAMLR has required 100% observer coverage of all fishing vessels. Independent onboard observers collate evidence of interactions with other species and discards of target catch.
How does the MSC ensure krill is sustainable?
Fisheries certified to the MSC Fisheries Standard, must meet its three principles - a science-based set of requirements for sustainable fishing.
The three principles demand:
- Stocks are abundant and self-sustaining,
- Fisheries mitigate their impact on other species, habitats and ecosystems,
- Fisheries are under effective management.
The Standard has further requirements for assessing the sustainability of keystone species, which all certified Antarctic krill fisheries must meet. These extra requirements check not just the abundance of the stock but also whether the stock status has impacts on predator and ecosystem needs.
Under the second principle, data from onboard observers must be used to ensure fisheries take active measures to improve any impacts on local wildlife such as penguins and whales.
All fisheries certified as sustainable to the MSC Fisheries Standard are in full compliance with MSC and CCAMLR (fisheries management) regulations.
Assessments to the Standard are carried out annually by accredited, independent certifiers and stakeholder input is welcomed throughout the assessment process.
In 2021, 75% of all Antarctic krill catches were by fisheries independently certified as sustainable to the MSC Fisheries Standard.
What are krill fisheries doing for Antarctic wildlife?
Founded in 2012, the Association of Responsible Krill harvesting companies (ARK) is a group of eight krill fishing companies from four CCAMLR member countries (Norway, the Republic of South Korea, Chile, and China).
The total fishing capacity of ARK members represents over 90% of all krill catches in CCAMLR waters.
ARK fisheries take voluntary steps to help protect Antarctic wildlife. These measures go beyond the requirements of CCAMLR directives and support their ability that meet or exceed the MSC Fisheries Standard.
To mitigate the impacts of krill fishing on penguin colonies, fishing industry partners, represented by ARK in collaboration with WWF, have implemented a voluntary seasonal buffer zone of 4,500km2 – the equivalent of over 84,000 football fields.
This seasonal buffer zone encompasses the foraging and chick-rearing areas for over 74% of chinstrap, almost 98% of gentoo, and above 91% of Adélie penguin colonies, offering significant protection to most penguins around krill fisheries.
Further year-round voluntary closures around the Antarctic peninsula provide additional protection for penguin colonies during their breeding seasons.
ARK have implemented the use of seal exclusion devices on their vessels. In a direct and timely response to scientific observer findings of four whale mortalities between 2020 and 2022, participating vessels adapted these exclusion devices to also exclude whales from the trawl mouth.
Since the whale exclusion devices were fitted no further whale incidents have been recorded and the innovation is expected to be adopted industry-wide.
Furthermore, ARK fishing vessels are using eco-harvesting techniques by keeping fishing nets underwater for longer, reducing energy consumption. The technique also benefits wildlife populations: by avoiding repeated casting and retrieval of fishing gear, the risk of unintentional interactions is lessened.
Krill fisheries use sonar and echo-sounders to locate krill but certified fishery and ARK member, Aker Biomarine, has invested heavily in more state-of-the-art technology e.g., using SailBuoy a small, non-invasive, solar-powered surface drone and an ocean drone for krill data collection. The drones are key for locating krill but also provide invaluable data that is shared with CCAMLR to improve scientific knowledge on krill biomass.
Overall, because of CCAMLR, MSC and ARK management systems, Antarctic krill fisheries operating within all three programs, rate among the most environmentally sustainable and well-regulated fishing operations on the planet.