The genus Clupea, the herrings, contains three species. The two main species, Atlantic herring (C. harengus), and Pacific herring (C. pallasii), both from northern waters, are broken into several major subspecies. The smaller and less common Araucanian herring (C. bentincki) inhabits the southeast Pacific. A fourth Asian species, C. manulensis is of uncertain validity. Clupea, the largest of which reach 46 cms, are recognized as the most populous fish in the world, and because of this, perhaps the most important species. They swim in enormous, fast-moving schools, and eat large quantities of zooplankton, especially copepods. In turn, they an provide food source for many predators, including humans (also seabirds, dolphins, porpoises, striped bass, seals, sea lions, whales, sharks, dog fish, tuna, cod, salmon, and halibut). They were overfished in 1990. An oily fish, they are prepared in many ways such as salted, pickled, fermented, raw, dried and smoked, with many regional specialties.

(Binohlan 2011; The Herring Network; Wikipedia 2012)