Sterletus gueldenstaedtii

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 50-51

Sterletus gueldenstaedtii

Common name. Russian sturgeon

Diagnosis. Distinguished from other species of Acipenser and Sterletus in West Asia by: ○ head triangular, if seen from below / ○ base of barbels closer to tip of snout than to mouth / ○ barbels not fimbriate / ○ lower lip interrupted in middle / ○ 15–31 gill rakers / ○ 8–19 dorsal scutes / ○ 24–50 lateral scutes / ○ 6–13 ventral scutes / ○ snout short (22–36 % HL) and blunt / ○ head length 17–19 % TL / ○ many star-shaped bony denticles of various sizes between dorsal and lateral scutes / ○ dorsum golden brown, belly yellowish white / ○ dorsal profiles of head and body forming an obtuse angle / ○ no plates along posterior part of anal base / ○ 0–1 plate along lower edge of caudal peduncle / ○ tetraploid. Size up to 2360 mm TL and 115 kg. Evidence does not support records of size up to 4000 mm TL. Subfossil specimens about 3000 mm TL.

Distribution . Caspian, Black, and Azov Sea basins.

Habitat. At sea, shallow coastal and estuarine areas. In freshwaters, deep parts of large rivers with moderate to fast currents. Spawns in strong currents (1.0– 1.5 m /s) in large and deep rivers on stony or gravelly bottoms.

Biology. Anadromous and freshwater populations.A complex pattern of spawning migrations includes spring and autumn runs. Individuals migrating in spring enter freshwater just before spawning, tend to spawn in lower reaches of rivers ( 320–650 km in unregulated Ural). Individuals migrating in autumn overwinter in rivers and spawn further upstream in spring ( 900–1200 km in Ural).Males first spawn at 8–13 years, females at 10–16 years. Females spawn every 4–6 years and males every 2–3 years in April–June when temperatures rise above 10°C. Larvae drift on currents; juveniles then move to shallower habitats before migrating to sea during their first summer. Remain at sea until maturity. Feeds on a wide variety of benthic molluscs, crustaceans and small fish.

Conservation status. CR; survival appears to depend only on stocking. Very rare in Black Sea basin. Almost all spawning grounds lost due to dam construction. Heavily overfished. Caspian populations are under massive pressure from overfishing and loss of spawning habitat. Almost all migrating spawners are poached below Volgograd dam.

Further reading. Vlasenko et al. 1989a (biology).

Figures

Sterletus gueldenstaedtii

Distribution