Anchovy Anchovy An anchovy is a small, common forage fish of the family Engraulidae. Most species are found in marine waters, but several will enter brackish water and some in South America are restricted to fresh water. The more than 140 species are placed in 17 genera; they are found in the Atlantic, Indian and Pacific Oceans, and in the Black Sea and the Mediterranean Sea. Anchovies are usually classified as oily fish. Anchovies are small, green fish with blue reflections due to a silver-colored longitudinal stripe that runs from the base of the caudal (tail) fin. They range from in
Fin increase thrust produced by the tail of swimming mackerel". Fish use multiple fins, so it is possible that a given fin can have a hydrodynamic interaction with another fin. In particular, the fins immediately upstream of the caudal (tail) fin may be proximate fins that can directly affect the flow dynamics at the caudal fin. In 2011, researchers using volumetric imaging techniques were able to generate "the first instantaneous three-dimensional views of wake structures as they are produced by freely swimming fishes". They found that "continuous tail beats resulted in the formation of a linked chain of vortex rings" and