STATE OF POPULATION OF PIKE PERCH OF THE LOWER FLOW OF THE URAL RIVER
Autor: | Sergey Vladimirovich Kuzmenko, Alexander Nickolaevich Nevalennyy, Nikolay Nikolayevich Popov, Arkadii Fedorovich Sokolsky |
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Rok vydání: | 2018 |
Předmět: | |
Zdroj: | Vestnik of Astrakhan State Technical University. Series: Fishing industry. :83-89 |
ISSN: | 2309-978X 2073-5529 |
Popis: | In domestic and foreign markets a great demand for pike perch is caused by the fact that its meat is a digestible and dietetic product. Due to growing scales of exploration and production of oil, as well as of poaching in the last years pikeperch and other species suffer from anthropogenic load. In 1990 spike perch catches reached 4.49.000 tons and made 1/3 of total catch of semi anadromous and river fish. During the last decade pike perch catches have decreased in the Ural-Caspian region up to 380 t, according to data of 2016. The study of pike perch populations on fishing zones of the Ural (delta, Malaya Dambinskaya fishing ground) covered the data obtained in 2010-2016. There have been studied migrating periods of pike perch to the spawning grounds. Since 2011 there has been stated a drastic decrease of sire number and a much less catch of pike perch per one casting in autumn, which was caused by the permission for fishing in the coastal part of the Caspian Sea. According to the research data, there have been given size-weight parameters of pike-perch producers in the Ural river during 10 years (2006-2016). The tendency to juvenation of spawning pike perch species is stated due to increasing share of the first spawning species, as well as due to decreasing number of male species in the catches as their age increased. Fultin and Clark’s condition coefficients are shown. Importance of pike perch as a commercial species in the ecosystem of the Ural-Caspian fishery zone contributes to define the following recommendations on saving and restoring pike perch population: to reduce commercial catches in the estuarine area of the Ural; to forbid commercial fishing in the coastal area of the north-east part of the Caspian Sea; to intensify fishery inspection in the Urals. |
Databáze: | OpenAIRE |
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