Interannual changes in the growth parameters of the anchovy Engraulis encrasicolus ponticus (Aleksandrov, 1927) (Clupeiformes, Pisces) inhabiting the south-western shelf of Crimea in 2000–2020

   Analysis of the growth characteristics of individuals and the parameters of the anchovy population living on the south-western shelf of the Crimea under conditions of sea surface temperature (SST) changes in 2000–2020 has been performed. The material for our research was the catches of anchovy by trawls on few fishing vessels on the south-western shelf of the Crimea during the wintering period (November–March). Linear SST trends on the south-western shelf of the Crimea were estimated. The average annual SST increase in 2000–2020 was 0.055 °C. It is shown that the 20-year period can be roughly divided into three periods according to the nature of SST changes, namely: 2000–2007 (I period), 2008–2013 (II period), and 2014–2020 (III period) according to the SST change rate inside each of them. In the warmest period (2014–2020), compared with 2000–2007, the average length of the anchovy increased by 5 %, the average weight by 15 %, and the average anchovy age in catches by 1.2 times, respectively. There was an increase in the rate of linear and weight growth in periods II and III relative to period I. A positive correlation (Pearson’s correlation coefficient r = 0.89) between the increase in the average annual SST and the maximum anchovy length has been confirmed. In the period of 2000–2020, the proportion of older age groups for anchovy catches on the south-western shelf of the Crimea increased, which led to an increase in the proportion of larger, well-fed individuals living on the south-western shelf of the Crimea, to an increase in the average size and weight of fish. It is assumed that the increase in the average annual SST in 2000–2020 had a positive impact on the development of anchovy, which belongs to the thermophilic fish complex.

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