The ship sturgeon, also known as the fringebarbel sturgeon, ship sturgeon, spiny sturgeon, or thorn sturgeon (''Acipenser nudiventris''), is a species of fish in the family

Acipenseridae Sturgeon is the common name for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous, and are descended from other, earlier acipenseriform fish, which date back to the Early ...

. These fish are typically found along the

benthos Benthos (), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environme ...

Feeding

''Acipenser nudiventris'' typically feed on other animals near the

benthos Benthos (), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.mollusks Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapoda, decapods, ostracoda, seed shrimp, branchiopoda, branchiopods, argulidae, fish lice, krill, remipedes, isopoda, isopods, barnacles, copepods, ...

s, and other smaller fish.

Reproduction

''Acipenser nudiventris'' are usually

anadromous Fish migration is mass relocation by fish from one area or body of water to another. Many types of fish migrate on a regular basis, on time scales ranging from daily to annually or longer, and over distances ranging from a few metres to thousa ...

—meaning they live in saltwater and travel to freshwaters to deposit eggs—but some can spend their entire life cycle in freshwater. Because they travel from saltwater to freshwater to spawn, they often live nearby estuaries. Migration to freshwaters for deposition of eggs occurs during spring between the months of March and May, and fall between October and November. On average, female bastard sturgeon produce between 200,000 and 300,000 eggs over the course of their lifetime. The young ''Acipenser nudiventris'' can live in freshwater for years following birth prior to traveling to the sea, though many migrate to the sea soon after birth. The average time between birth of subsequent ''Acipenser nudiventris'' is around 15 years; variation in generation time of this species is somewhat dependent on human fishing patterns and whether the species is thriving in its environment.

Conservation status

Formerly abundant in the

Black Black is a color which results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. Black and white ha ...

, Aral and Caspian seas, its range is now primarily limited to the

Ural River The Ural (russian: Урал, ), known before 1775 as Yaik (russian: Яик, ba, Яйыҡ, translit=Yayıq, ; kk, Жайық, translit=Jaiyq, ), is a river flowing through Russia and Kazakhstan in the continental border between Europe and Asia ...

(in

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-ei ...

and

Kazakhstan Kazakhstan, officially the Republic of Kazakhstan, is a transcontinental country located mainly in Central Asia and partly in Eastern Europe. It borders Russia to the north and west, China to the east, Kyrgyzstan to the southeast, Uzbeki ...

), with possible

relict A relict is a surviving remnant of a natural phenomenon. Biology A relict (or relic) is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas. Geology and geomorphology In geology, a r ...

populations in the

Rioni River The Rioni ( ka, რიონი, ; , ) is the main river of western Georgia. It originates in the Caucasus Mountains, in the region of Racha and flows west to the Black Sea, entering it north of the city of Poti (near ancient Phasis). The city o ...

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

and the

Safid Rud The Sefid-Rud ( fa, سفیدرود, lit=white river, glk, اسپي بيه, ''Espī bīeh'') (also known as Sepid-Rud) is a river approximately long, rising in the Alborz mountain range of northwestern Iran and flowing generally northeast to ent ...

Iran Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...

. One of the most established populations is one in Lake Balkhash in

, well outside its natural range, where they were introduced in the 1930s for commercial purposes. A decline in the abundance of ''Acipenser nudiventris'' has been reported due to overfishing and damming, which have led to limitations placed on fishing for bastard sturgeon in areas such as the Ural River. In order to alleviate concerns with rapidly decreasing ''Acipenser nudiventris'', an effort was made to raise these fish in captivity before releasing them back into rivers they once inhabited. Acipenser nudiventris head

References

Acipenser Fish of the Caspian Sea Fish of the Black Sea Aral Sea Fish of Europe Fish of Western Asia Critically endangered fish Critically endangered fauna of Asia Critically endangered biota of Europe Taxonomy articles created by Polbot Fish described in 1828 {{Acipenseriformes-stub