Krill are small, exclusively marine crustaceans belonging to the order Euphausiacea, found in all the world's oceans
. They play a crucial role in the aquatic food chain and are the main staple in the diets of hundreds of different animals, from fish to birds to baleen whales
. Some key facts about krill include:
- Krill are plankton, meaning they are small freshwater or marine organisms that cannot swim against the current and exist in a state of drift
- They feed on phytoplankton, microscopic, single-celled plants that drift near the ocean's surface and live off carbon dioxide and the sun's rays
- Krill are an important element of the aquatic food chain, converting the primary production of their prey into a form suitable for consumption by larger animals that cannot feed directly on the minuscule algae
- Krill are fished commercially in the Southern Ocean and in the waters around Japan, with an annual global harvest of 150,000–200,000 tonnes
- Most of the krill catch is used for aquaculture and aquarium feeds, as bait in sport fishing, or in the pharmaceutical industry
- In Japan, the Philippines, and Russia, krill are also used for human consumption and are known as okiami
- Krill are rich in protein and omega-3 fatty acids, which are under development as human food, dietary supplements, livestock food, and pet food
- Antarctic krill (Euphausia superba) are among the largest of the 85 known krill species, with an estimated biomass of 125 million to 6 billion tons in the waters around Antarctica
- Antarctic krill can live up to 10 years and are an essential food source for many marine animals, including penguins, seals, and baleen whales
- Recent studies show that Antarctic krill stocks may have dropped by 80% since the 1970s, partly due to ice cover loss caused by global warming, which removes a primary source of food for krill: ice-algae
