Alosa Alosa Alosa is a genus of fish, the river herrings, in the family Clupeidae. Along with other genera in the subfamily Alosinae, they are generally known as shads. They are distinct from other herrings by having a deeper body and spawning in rivers. Several species can be found on both sides of the Atlantic Ocean and Mediterranean Sea. Also, several taxa occur in the brackish-water Caspian Sea and the Black Sea basin. Many are found in fresh water during spawning and some are only found in landlocked fresh water. These fishes lived from the Eocene to Quaternary (from 55 million
Alosa sources, predators, etc. Since many adult "Alosa" species die after spawning, the young generally have to migrate to the sea from the spawning grounds. Duration of migration varies among fish, but it can greatly affect survival. Reproduction varies by species. Studies done on "Alosa" in Iranian waters have shown that spawning varies in time, place, and temperature of the waters they inhabit. Fecundity may also vary. Species are known to spawn as early as April or as late as August. Temperatures range from about 11 to 27 °C. Fecundity can range from 20,000 to 312,000 eggs. Eggs are pelagic. The