Capelin are small silver fish that usually are found off the shores of Newfoundland, on the Grand Banks. Once a year, in late June or early July, when the moon is right they swim to beaches to spawn. There are so many fish near shore at this time that you can scoop them up with baskets or throw nets. The waves are alive with fish. Most of the male capelin, and some of the females die after spawning so a fishery from shore is sustainable.
Capelin eat plankton, and are themselves eaten by codfish, seabirds, whales, and seals. Since the collapse and subsequent moratorium on the North Atlantic cod stocks, more research has been done into the role of these tiny fish.
Unfortunately, these fish which form the base for all the sealife of the Grand Banks are themselves being fished. The females with roe are prized in Japan as bar snacks. They are caught before spawning can take place, and the undesirable males and smaller females are simply discarded. This is how the Japanese ruined their own capelin stocks. With less capelin available, the seabirds and seals prey more heavily on juvenile codfish.