Capelin

Capelin (Mallotus villosus) is a small forage fish in the family Osmeridae. Native to cold waters of the North Atlantic and adjacent Arctic seas, capelin form large seasonal schools and are a key prey item for numerous marine predators, as well as an important commercial species.

Geographic range extends from western Greenland and eastern Canada to Iceland, Norway, and parts of the Barents Sea. Capelin inhabit cold, productive shelf waters and undertake a pronounced north–south seasonal migration, moving toward coastal zones to spawn in shallow, sandy beaches.

Adults typically reach about 12–20 cm in length and can live several years. They feed mainly on zooplankton, including copepods and amphipods, while juveniles feed on smaller planktonic organisms. Capelin form dense schools that can cover large areas of the water column.

Spawning occurs in late winter to spring along beaches and brackish shores. Eggs adhere to the substrate, and the hatchlings enter shallow nurseries before migrating back to deeper waters. Capelin populations show pronounced interannual fluctuations tied to ocean conditions.

Commercial fisheries target capelin for both direct human consumption and for value-added products such as capelin roe, used as masago in sushi. The fish is also reduced to fish meal and fish oil. Major producers include Iceland, Norway, Canada, and Greenland, with management through national and regional quotas.

As an important forage species, capelin support the diets of cod, haddock, seabirds, and whales. Changes in capelin abundance influence predator populations and marine ecosystem dynamics, and stock assessments guide efforts to ensure sustainable exploitation.