Atlantic herring
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Atlantic herring Clupea harengus is the most abundant fish species of the world, living in large schools (swarm). Growing up to 45 centimeters in length and more than half a kilogram in weight, they feed on copepods, krill and small fish and are food for sealss, whales, cod and other larger fish.
The Atlantic herring fishery has long been an important part of the economy of New England and the Canadian Maritime provinces, because the fish congregates relatively near the coast in massive schools. North Atlantic herring schools have been measured up to 4 cubic kilometers in size, containing an estimated 4 billion fish.