Sturgeon (Acipenser) is a genus of fishes, of which some twenty different species are known, from European, Asiatic and North American rivers. They pass a great part of the year in the sea, but periodically ascend large rivers, some in spring to deposit their spawn, others later in the season for some purpose unknown; only a few of the species are exclusively confined to fresh water. None occur in the tropics or in the southern hemisphere.












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In Russia the fisheries are of immense value. Early in summer the fish migrate into the rivers or towards the shores of freshwater lakes in large shoals for breeding purposes. The ova are very small, and so numerous that one female has been calculated to produce about three million in one season. The ova of some species have been observed to hatch within a very few days after exclusion. Probably 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 they have attained maturity their growth appears to be much slower, although continuing 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 to be still alive in 1866. Professor von Baer also states, as the result of direct observations made in Russia, that the Hausen (Acipenser huso) attains to an age of from 200 to 300 years.

Above Images Come From U.S. Fish & Wildlife Service



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