Clupea Clupea Clupea is genus of planktivorous bony fish belonging to the family Clupeidae, commonly known as herrings. They are found in the shallow, temperate waters of the North Pacific and the North Atlantic oceans, including the Baltic Sea. Three species of "Clupea" are recognized. The main taxa, the Atlantic herring ("Clupea harengus") and the Pacific herring ("Clupea pallasii") may each be divided into subspecies. Herrings are forage fish moving in vast schools, coming in spring to the shores of Europe and America, where they form important commercial fisheries. The species of "Clupea" belong to the larger family Clupeidae (herrings, shads,
Geology of the North Sea As the rifting stopped, then regional subsidence occurred creating an intracratonic sedimentary basin. Subsidence occurred due to lithosphere cooling. Some of this uplift was along old lines of weakness from the Caledonian and Variscan Orogenies long before. Intraplate compression was caused when the Atlantic Ocean basin formed. the Mid-Atlantic spreading ridge has been busy separating east from west. Greenland separated from North America and the rifting altered direction during the Paleogene, which caused Northern Europe to separate from Greenland. During the Eocene period, the last land bridge across the Atlantic sank. The Alpine Orogeny that occurred about 50 Ma was