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Sturgeon (Acipenser) is a genus of freshwater fish, which includes twenty known species from European, Asiatic and North American rivers. They spend a large part of the year in the sea, but periodically migrate to large rivers to deposit their spawn or for unknown reasons. Only a few species of sturgeon are confined to fresh water. No species occur in the tropics or in the southern hemisphere.


 


Sturgeons generally range in size from 8 to 11 feet (2.5 to 3.5 m) in length, and some species grow to a much larger size.

Sturgeon are bottom-feeders. They stir up the soft bottom of the sea with their projecting wedge shaped snout, and use their sensitive barbels detect shells, crustaceans and small fish to eat. Since they don't have teeth, they are unable to seize larger prey.


Early in summer, sturgeon migrate to rivers and freshwater lakes in large shoals for breeding purposes. The ova are very small and very numerous! One female is said to have produced about three million in one season. The ova of some species have been observed to hatch very shortly after fertilization. The growth of the young is very rapid, but we do not know how long the fry remain in fresh water before their first migration to the sea. After the young sturgeon have matured, their growth slows substantially, but will continue for many years. Frederick the Great placed a number of them in the Garder See Lake in Pomerania about 1780; some of these were found alive in 1866. Professor von Baer also claims that he has directly observed that the Hausen (Acipenser huso) can live up to 100 years.


Caviar: In places where sturgeon is harvested in large quantities, like the rivers of southern Russia and on the great lakes of North America, their flesh is dried, smoked or salted. The ovaries, which are very large, are prepared for caviar through beatings with switches, and then pressed through sieves, so that the eggs can be collected in a tub.

 

Sturgeon Trivia:

Some people believe that sturgeon scales are hard enough to repel bullets.

Isinglass, a form of gelatine from sturgeon fish bladders, is used as processing aids in the "fining" or filtration process of wine making.

In the plot of Gordon Korman's MacDonald Hall books (especially in the third book, Beware the Fish) there are many references to this kind of fish: the headmaster of the school is called Mr. Sturgeon, and is nicknamed The Fish.

 

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 Kingdom: Animalia

 Phylum: Chordata

 Class: Actinopterygii

 Order: Acipenseriformes

 Family: Acipenseridae

 Genus: Acipenser