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,
North Atlantic Gyre the central role it plays in the thermohaline circulation, bringing salty water west from the Mediterranean Sea and then north to form the North Atlantic Deep Water. The North Atlantic Gyre traps man-made marine debris in the North Atlantic Garbage Patch, similar to how the North Pacific Gyre traps debris in the Great Pacific Garbage Patch. The North Atlantic Gyre forms the Sargasso Sea, noted for its still waters and dense seaweed accumulations. As with many oceanographic patterns, the North Atlantic Gyre experiences seasonal changes. Stramma and Siedler (1988) determined that the gyre expands and contracts with a seasonal variance;