Sterlet (Acipenser ruthenus)
The sterlet (Acipenser ruthenus) is a common Eurasian species of sturgeon, one of the smaller species of sturgeon. It is a common domestic species in the UK and Europe and an angling species all over the world. It can also be grown for eating or for its caviar or isinglass.
Location
This sturgeon inhabits rivers that flow into the following seas: Caspian, Black, Azov, Baltic, White, Barents, Kara, and inhabits both the Black and Caspian seas, and ascends rivers to a greater distance from the sea than any of the other sturgeons; thus, for instance, it is not uncommon in the Danube at Vienna, but specimens have been caught as high up as Regensburg and Ulm. It is more abundant in the rivers of Russia. As early as the 18th century attempts were made to introduce this valuable fish into Sweden and the Province of Prussia, but without success.
Physical Appearance
The sterlet may reach 16kg in weight and 100 to 125cm in length, rarely exceeding a length of 3 ft. It is quite variable in coloration, but usually has a yellowish ventral side. It is distinguishable between other European species of sturgeons by the presence of a great number of whitish lateral scrutes, fringed barbels, and an elongated and narrow snout, highly variable in length.
Feeding Habits
The sterlet's main source of food is benthic organisms; they commonly feed on crustaceans, worms, and insect larvae.
Life Span
The sterlet commonly reaches the age of 22 to 25 years.
Sexual Maturity
Males: 3-7 years, females: 5-12 years
Fecundity
Females may lay from 15,000-44,000 eggs.
Spawning Period
Middle of April - End of May -- Beginning of June.
Spawning Requirements
Sexually mature adults. Water temperature preferably 12-17°C.
As Pond Fish
Sterlets are found in aquarist stores. They prefer medium sized and large ponds, require good water conditions, and may get entangled in plants or blanketweed or other algae. They are very friendly fish; when they are older, they will happily poke their noses out of the water for you to touch. They eat crustaceans and molluscs; however, they need special food such as TetraPond Sturgeon/sterlet sticks.
Wild Sterlet habits
Wild Sterlets are thought to be even tastier than normal sterlet flesh, probably from the wide range in their diet. Wild Sterlets are opportunistic carnivores, eating shrimps, crabs, worms and small fish and sometimes supplementing it with algae when they are desperate. They often sit at the bottom of lakes and rivers gliding around in the mud for food. They also can go into caves. They also feed on newborn and young sterlets. Sterlets will rarely go for prey larger than 10 centimetres.
All text in this article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Sterlet".