krillit

Krillit is the term used in several Scandinavian languages to refer to krill, the small shrimp-like marine crustaceans that belong to the order Euphausiacea. In English, they are simply called krill. Krill occur in oceans worldwide, with the greatest biomass in cold waters of the Southern Ocean. Individuals range from about 1 to 6 centimeters in length and are primarily holoplanktonic filter feeders, consuming phytoplankton and, to a lesser extent, microzooplankton. Through their feeding, krill link primary production to a wide range of marine predators, including whales, seals, penguins, seabirds, and many fish. They often form dense swarms and undertake vertical migrations that move nutrients through the water column.

Taxonomy and life cycle: Krill are crustaceans in the order Euphausiacea, within the class Malacostraca. The most well-known species is Euphausia superba, the Antarctic krill; other representatives include Euphausia pacifica and various Thysanoessa and Nyctiphanes species. Reproduction is sexual, with eggs released into the water and larvae passing through several naupliar and copepodite stages before reaching maturity. Growth typically spans one to several years, varying with species and environmental conditions.

Ecology and human use: Krill are a cornerstone of many marine ecosystems, serving as a key prey item for large predators. They are harvested commercially, especially Antarctic krill, for animal feed, aquaculture, and krill oil supplements. Management is coordinated by CCAMLR to limit ecological impacts and promote sustainable harvesting, particularly under changing ocean conditions.