A License to Krill

Krill, tiny crustaceans that look like small prawns, may only grow to be 5 centimeters long and weigh just 2 grams, but their size is dwarfed by their value. Krill may be the most important creatures in the Antarctic ecosystem, providing food for whales, penguins, squid and seabirds; krill are also the most important food source for many species of fish. In addition, krill can be worth billions of dollars as a source of health-promoting compounds.

Many people estimate krill is the most abundant creature on the planet, forming one of the biggest accumulations of marine life in the world. It spends the greater part of its life in large and dense shoals that cover several kilometers in every direction, with up to 30,000 of them per cubic meter. This forming of shoals means it can be fished using trawl nets. It is estimated the total weight of krill in the Antarctic is somewhere between 50 million and 500 million tons.

The krill leads a pelagic life, in the upper reaches of the sea, and moves up and down in columns of water. It disappears into the depths so as to avoid being eaten during the day and comes up to the surface again to eat plant and animal plankton in the evening. Over the course of the Antarctic summerfrom January to Februarya krill can lay up to 10,000 eggs, which sink to a depth of about 2,000 meters before hatching. At that point, the larvae begin their long journey, which lasts up to ten days, up to the surface to eat. The krill grows by replacing its shell. It sheds the old shell and expands while the new shell is still soft.

It is uncertain how old a krill can become; in captivity, they have lived as long as 11 years. It is, therefore, not unreasonable to assume krill living in the wild could live between six and eight years. Studies have further shown krill can survive for as long as 200 days without food by lowering their metabolism and reducing in size, an ability that is entirely unique to the krill.

Unfortunately, this ability to adapt has become increasingly critical. The krill is under a great deal of pressure, not only from the growing fishing fleet, but also as a result of climate change. The food chain in the Antarctic is very short and closely interwoven, and dramatic changes in the population of any species have major consequences for other species. This makes it extremely important to have good, ecosystem-based management to also safeguard these resources for the future. This must also take into account the ecological interplay between the krill, the species that depend on it and commercial fishing.

Managing the Resource

For almost 40 years, Antarctic krill fishing has been the biggest fishery in the Antarctic Ocean; Russia, Japan, Chile, South Korea, Poland and Norway are important players. From 1990 to 2000, about 100,000 tons of krill was harvested annually; this figure has grown considerably since 2001. Today, Antarctic krill are managed and regulated by the Convention for the Conservation of Antarctic Marine Living Resources (CCAMLR), which was founded in 1981. The quotas in the area where fishing is allowed have been set on the basis of the precautionary principle, and it is only permitted to catch 600,000 tons a year. This is to ensure krill resources are not over-fished in some areas and to prevent depriving marine species of their primary food source. In addition, CCAMLR works with the World Wildlife Fund (WWF) on sustainability and scientific research projects to best manage the Antarctic ecosystem.

Companies such as Aker BioMarine have also developed sustainable programs to support krill harvesting endeavors. One such technology, eco-harvesting, means the krill are alive when harvested, keeping them from drying out and destroying the biomass via decomposition. Processing begins immediately onboard the vessel. In addition, Aker BioMarine and Aker Seafoods entered into formal cooperation with WWF to cooperate on sustainable harvesting of fish and krill, combating illegal fishing and ensuring traceability of fishery products. Under terms of the agreement, WWF receives financial support for its conservation work, and Aker gets a partner that can contribute toward the company meeting its objective of sustainable harvesting of natural resources.

Health Benefits

This work is all critical to preserving a resource with fantastic health potential. The Antarctic krill is considered the healthiest nutrient the sea can offer. Krill oil consists of a unique triple power combination of bioactive compoundsmarine phospholipids, omega-3 essential fatty acids (EFAs) bound to phospholipids and the potent antioxidant astaxanthinall which have documented health benefits for humans.

Purified krill oil is believed to have beneficial effects due to its ability to modulate the inflammatory response.

Krill oil is the only available source of omega-3s bound to phospholipids. Omega-3-bound phospholipids may be more bioavailable than other forms of omega-3. Krill oil is also a source for one of natures strongest antioxidantsthe carotenoid astaxanthin.

Antioxidants protect the body against free-radical damage, and astaxanthin is particularly potent in protecting the cells as well as serving as a powerful anti-inflammatory compound. When consumed along with omega-3-bound phospholipids, astaxanthin enhances and supports several of the omega-3 benefits. 

Nina Jensen ([email protected]) is a marine expert with World Wildlife Fund (WWF) International. She has worked with Aker BioMarine (www.AkerBiomarine.com ) on development of its sustainable harvesting programs.