Pontic shad Pontic shad The Pontic shad ("Alosa immaculata", previously "Alosa pontica"), also referred to as the Black Sea shad or Kerch shad, is a species of clupeid fish in the genus "Alosa", native to the Black Sea and Sea of Azov basins. "Alosa immaculata" lives in the Black Sea and Sea of Azov, and adults migrate up rivers to spawn. It may also be found in the Marmara Sea in Turkey. It currently migrates up and spawns in six rivers: the Danube, Dnieper, Dniester, Southern Bug, Don and Kuban Rivers. Previously the migrations reached far upstream, up to 1,600 in Danube
Atlantic herring not considered to be an Arctic species. The small-sized herring in the inner parts of the Baltic Sea, which is also less fatty than the true Atlantic herring, is considered a distinct subspecies ("Clupea harengus membras") ("Baltic herring"), despite the lack of a distinctive genome. The Baltic herring has a specific name in many local languages (Swedish "strömming", Finnish "silakka", Estonian "räim", "silk", Livonian "siļk", Russian "салака", Polish "śledź bałtycki, sałaka", Latvian "reņģes", Lithuanian "strimelė") and is popularly and in cuisine considered distinct from herring. For example, the Swedish dish surströmming is made from Baltic herring. Herrings reach sexual maturity