PRESENT STATUS OF NATURAL REPRODUCTION OF STURGEON (ACIPENSERIDAE) IN THE URAL RIVER

Autor: Askarbay Kadralyevich Kamelov, Erbolat Latifovic Kadimov, Saule Zhangirovna Asylbekova, Evgeniy Vyacheslavovich Kulikov, Kuanysh Baibulatovich Isbekov
Rok vydání: 2018
Předmět:
Zdroj: Vestnik of Astrakhan State Technical University. Series: Fishing industry. :81-88
ISSN: 2309-978X
2073-5529
DOI: 10.24143/2073-5529-2018-2-81-88
Popis: In the current conditions of a critical reduction of sturgeon stocks and the imposed moratorium on industrial sturgeon catching it is necessary to take urgent and cardinal measures to save the Caspian populations of these valuable fish species. To restore the number of sturgeons in the Ural-Caspian basin it is first of all necessary to increase the efficiency of natural reproduction. The Urals is the only river in the basin of the Caspian Sea with an undisturbed hydrological regime that allows to maintain the normal dynamics of migrations of sturgeon fishes and conditions for spawning and the subsequent ramp of the young. The current state of the natural reproduction of sturgeon in the Ural river was analyzed; data on the dynamics of sloping migration of young sturgeon, their number and mass are given. It has been established that the main factors affecting the reproduction of sturgeon are the hydrological conditions of the river of a particular year, as well as the number of producers that are allowed to enter spawning grounds. It has been stated that the beginning of sturgeon juveniles ramp into the Ural River shifted to later period and can be registered only since June; ramp duration has greatly decreased; average mass of ramping juveniles also decreased; since 2007 Acipenser nudiventris juveniles haven’t been observed, and since 2010 stellate sturgeon juveniles haven’t been come across. It is shown that at present, due to a number of reasons, the efficiency of natural reproduction of sturgeon in the Ural River is reduced to zero.
Databáze: OpenAIRE
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