Fish
Capelin
Mallotus villosus · also called capelins
For a few nights each year in places like Newfoundland, the shoreline itself seems to come alive as capelin roll onto the beach in almost unimaginable numbers, spawning directly in the wet sand before the tide carries them back out. Nearly every major predator in the North Atlantic and Arctic, from cod to whales, times at least part of its own year around this one small fish’s abundance.
Overview
Capelin, Mallotus villosus, is a small, short-lived forage fish found across cold North Atlantic and Arctic waters. Mass beach-spawning events known as capelin rolling bring enormous numbers of fish directly onto shore, feeding a wide range of larger predators throughout the region.
A keystone fish with a short life
Living fast and often dying shortly after spawning, capelin populations can rebound quickly under good conditions, but their numbers are also sensitive to shifting water temperatures, changes that ripple outward to affect cod, seabirds, seals, and whales that all depend heavily on capelin as food.
Status
Least Concern overall, though regional populations have declined in parts of the North Atlantic, with fishery management aimed at maintaining sustainable numbers given the species’ outsized ecological role.
Capelin: common questions
What is capelin rolling?
Capelin rolling refers to a mass beach-spawning event in which enormous numbers of capelin swim directly onto beaches, particularly well documented in places like Newfoundland, to lay and fertilise eggs in the wet sand, a dramatic natural spectacle in which the shoreline can appear to turn silver with the sheer number of fish present.
Why are capelin considered so important to the North Atlantic ecosystem?
Capelin serve as a central forage fish for an unusually wide range of predators, including cod, seabirds, seals, and whales, meaning their abundance in a given year is directly tied to the breeding success and food availability of numerous larger species throughout the North Atlantic and Arctic food web.
Why do capelin populations sometimes decline suddenly?
Capelin distribution and abundance can shift considerably in response to changing water temperatures, and because the species has a relatively short lifespan with rapid population turnover, its numbers can fluctuate more quickly than longer-lived fish, sometimes triggering noticeable declines that then affect the predator species depending heavily on capelin as food.
Do capelin die after spawning?
Many capelin die shortly after spawning, consistent with the species' relatively short overall lifespan and rapid reproductive cycle, a life history pattern that, combined with the sheer number of eggs produced during mass spawning events, helps capelin populations recover relatively quickly under favourable environmental conditions.