Herring Herring Herring are forage fish, mostly belonging to the family Clupeidae. Herring often move in large schools around fishing banks and near the coast. The most abundant and commercially important species belong to the genus "Clupea", found particularly in shallow, temperate waters of the North Pacific and the North Atlantic oceans, including the Baltic Sea, as well as off the west coast of South America. Three species of "Clupea" are recognised, and provide about 90% of all herrings captured in fisheries. Most abundant of all is the Atlantic herring, providing over half of all herring capture. Fishes called herring are
Geology of the Baltic Sea on the Baltic water body became the Yoldia Sea. About 10,700 years ago the continued land rise separed the Baltic water body from the ocean again and Yoldia Sea turned into the Ancylus Lake. This lake lasted until 10,000 years before present when a new connection to the ocean was established, this time in the Danish straits forming the Littorina Sea. Land rise did not close off Littorina sea but it made its connection the ocean over time more shallow allowing less salt water to enter it, thus gradually it evolved into the current Baltic Sea with somewhat brackish water.