Comparative Assessment of Biological and Fisheries Productivity of Caspian Sturgeons Species
L. A. Zykov
Faculty of Geology and Geography/ Innovative Natural Institute, Astrakhan State University, Astrakhan, Shaumyana Sq., 1f, Russia.
T. F. Kurochkina
Faculty of Geology and Geography/ Innovative Natural Institute, Astrakhan State University, Astrakhan, Shaumyana Sq., 1f, Russia.
B. M. Nasibulina
Faculty of Geology and Geography/ Innovative Natural Institute, Astrakhan State University, Astrakhan, Shaumyana Sq., 1f, Russia.
M. Ali Attaala *
Faculty of Environmental Sciences and Marine Biology, Hadhramout University, Mukalla, Yemen.
N. N. Popov
Atyrau Affiliate of LLP Kazakh Fisheries Research Institute, Atyrau, Bergalieva Str. 80, The Republic of Kazakhstan.
*Author to whom correspondence should be addressed.
Abstract
Based on the model describing the dynamics of the number of generations of fish during the life cycle, the influence of growth and maturity on the biological and commercial productivity of conditional populations of Caspian sturgeon, formed from 1.0 million specimens of yearlings, was studied. On the biomass of conditional sturgeon populations, their gross output and catch are influenced by the length of yearlings, the size and age of maturity, the periodicity of spawning, the rate of linear and weight growth of individuals, and the degree of stocks catching. The highest yield of biomass and catch, obtained from 1 million yearlings, is observed in Beluga (Huso huso), then Ship Sturgeon (Acipenser nudiventris), Russian sturgeon (Acipenser gueldenstaedtii), Stellate Sturgeon (Acipenser stellatus) and sterlet (Acipenser ruthenus).
Keywords: Caspian sea, sturgeon, population, abundance, biomass, growth, mortality, catches