The bastard sturgeon, also known as the fringebarbel sturgeon, ship sturgeon, spiny sturgeon, or thorn sturgeon ( Huso nudiventris),
Taxonomy
Prior to 2025, it was placed in the genus
Acipenser, but this placement was found to be
Paraphyly, and it is more accurately placed in the genus
Huso.
Feeding
Huso nudiventris typically feed on other animals near the
benthos including: insect larvae,
Mollusca,
, and other smaller fish.
Reproduction
Huso nudiventris are usually
Fish migration—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
Huso 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
Huso 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 Sea,
Aral Sea and
Caspian seas, its range is now primarily limited to the
Ural River (in
Russia and
Kazakhstan), with possible relict populations in the
Rioni River in Georgia and the
Safid Rud in
Iran.
One of the most established populations is one in
Lake Balkhash in
Kazakhstan, well outside its natural range, where they were introduced in the 1930s for commercial purposes.
A decline in the abundance of
Huso 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
Huso nudiventris, an effort was made to raise these fish in captivity before releasing them back into rivers they once inhabited.
