Alosa algeriensis after spawning. Mortality after spawning is very common in species of the "Alosa" genus. This is primarily around the month of May. Alosa algeriensis Alosa algeriensis, the North African shad, is a Mediterranean species of clupeid fish in the shad genus "Alosa". "Alosa algeriensis" is primarily found in the Mediterranean Sea from northern Morocco to northern Tunisia. They are also found in Sardinia, Italy with landlocked populations in Lake Ichkeul, Tunisia and Sardinia, Italy. "Alosa algeriensis" males will begin upriver migration at about 3–4 years old while females do not begin until about 4–5 years old. The juveniles migrate to
Herring similar features. These silvery-coloured fish have a single dorsal fin, which is soft, without spines. They have no lateral line and have a protruding lower jaw. Their size varies between subspecies: the Baltic herring ("Clupea harengus membras") is small, 14 to 18 cm; the proper Atlantic herring ("C. h. harengus") can grow to about 46 cm (18 in) and weigh up 700 g (1.5 lb); and Pacific herring grow to about 38 cm (15 in). At least one stock of Atlantic herring spawns in every month of the year. Each spawns at a different time and place (spring, summer, autumn,