Long-term dynamics of reproductive potential and fishing of European sprat Sprattus sprattus (Linnaeus, 1758) (Pisces: Clupeidae) in the Black Sea

• German Zuev ^[1] ; Ekaterina Skuratovskaya ^[1]
  1. [1] A.O. Kovalevsky Institute of Biology of the Southern Seas of RAS, Moscow
• Localización: Thalassas: An international journal of marine sciences, ISSN 0212-5919, Vol. 38, Nº. 2 (October 2022), 2022, págs. 761-771
• Idioma: inglés
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• Resumen

  • Long-term (2000–2016) dynamics of size- and age structure, absolute individual fecundity, stock state and fishing of European sprat (Sprattus sprattus) in the northern part of the Black Sea were studied. Consistent decrease of all population parameters was registered in the Crimean region: in 2011–2016 compared to 2000–2004 the average length of spawning females decreased by 1.22 times and the absolute individual fecundity reduced by 2.39 times, the ratio between females and males decreased by 1.23 times and the sprat stock diminished by more than 2.5 times. As a result, the population fecundity decreased by more than 7 times. At the same time in the northern part of the Black Sea (from the Danube mouth to the Kerch Strait) the total sprat catch decreased by 2 times, the annual average catch fell by more than 2.3 times, while, on the Crimean shelf the total sprat catch increased by 1.2 times and the annual average catch was permanent. Consequently, the fishing load on sprat in the Crimean region increased by 2.5 times that led to overfishing and population deterioration. Thus, control of fishing is the necessary condition for preventing further deterioration sprat population state and preservation its reproductive potential. Local overfishing of sprat in the Crimean region together with long-term progressive deterioration of population biological state suggested subdivision of the total (one and indivisible) sprat stock in the Black Sea into separate stock units. This conclusion is considered as preliminary and further investigations in this area to be made.