The capelin or caplin, Mallotus villosus, is a small forage fish of the smelt family found in the Atlantic and Arctic oceans. In summer, it grazes on dense swarms of plankton at the edge of the ice shelf. Larger capelin also eat a great deal of krill and other crustaceans. Whales, seals, cod, squid, mackerel, beluga whales and seabirds all prey on capelin, in particular during the spawning season of the capelin while it migrates southwards. (source)