Alosa kessleri (Grimm, 1887)

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 65-66

Alosa kessleri

Common name. Black-back shad.

Diagnosis. Distinguished from other species of Alosa in Caspian basin by: ● dorsum black in spring / ● teeth on palatine and vomer well developed / ○ 59–92 thick gill rakers, shorter than gill filaments, with conspicuous lateral spines in juveniles but lost in adults / ○ head length 22–25 % SL / ○ eye diameter 15–20 % HL / ○ pectoral length 14–16 % SL. Size up to 400 mm SL.

individuals return to sea to feed.Juveniles inhabit floodplain and shallow riverine habitats, migrating to sea or estuarine habitats during first summer; move to sea in autumn and remain there until maturity. At sea,it feeds on a wide variety of zooplankton (especially crustaceans) and small fish.

Conservation status. VU; damming of major rivers significantly reduced available spawning habitat and migration routes in 20 th century. Decline appears to be continuing due to severe overfishing. Largest population in Danube.

Further reading. Kolarov 1991b (biology; as A. pontica ); Kottelat 1997 (systematics).

Distribution. Caspian Sea from where adults ascend Kura and Aras ( Azerbaijan) and Sefid ( Iran). Possibly also in other rivers. In European Caspian basin, in Volga, few enter Ural and Terek. Previously migrated Volga upstream to Kama and Oka systems. Migration now blocked by Volgograd Dam. There is evidence that it has formed landlocked populations in Volga reservoirs.

Alosa kessleri ; Volga delta, Russia; ~ 300 mm SL.

Habitat. At sea, pelagic, in a wide variety of habitats. Migrates to middle reaches of large rivers, spawning near banks in main channel and in almost still waters such as river bays, eddies, and floodplains.

Biology. Anadromous. Migrates upstream to spawn at 4–5 years.Enters rivers with immature gonads.Some spawn for 2–4 seasons, but most females die after spawning. Spawners appear along coast in March–April and enter rivers in April–May when temperatures reach about 9°C, peaking at 12–15°C. Spawning run originally lasted 30–50 days. Spawning begins in May–August when temperatures rise above 15°C and continue as long as temperatures remain at 15–23°C. Spawning is most intense between 4 and 10 pm. Eggs are bathypelagic. Spent fish return to sea to feed. In autumn, move to southern part of sea to overwinter. Juveniles migrate to sea or estuaries during their first summer until maturity. At sea, feeds on a wide variety of zooplankton, crustaceans, and small fish.

Conservation status. LC; damming of major rivers in 20 th century has significantly reduced available spawning

Alosa maeotica ; Black Sea, Romania; ~ 250 mm SL.

habitat and migration routes and heavily fished, especially on Volga, where largest population exists. Populations in West Asia small, most abundant in Kura and Sefid.

Further reading. Heckman 1991b (biology).