Role of water temperature spatio-temporal variability in European anchovy catches dynamics in the northwestern Black Sea

The aim: to characterize the Black Sea water temperature influence on the anchovy fishing.
Methods: the assessment is based on long-term data of anchovy catch statistics and oceanographic data on water surface temperature during the period 1992–2023 by the Copernicus marine project. The main hypothesis about the relationship between changes in water temperature and annual catches of European anchovy was carried out by methods of cross-correlation and spatial correlation analysis.
Novelty: statistical analysis of long-term data allowed us to find significant spatio-temporal patterns between parameters of anchovy fishing and changes in water temperature.
Results: a significant positive relationship between anchovy catches in the northwestern part of the Black Sea and the water surface temperature is shown: the average annual (with a lag of 1 year, rs = 0,50) and the average winter (without lag, rs = 0,42) temperature. Positive trends of average annual and average winter sea surface temperatures have been described. There were significant positive spatial correlations between water temperature and anchovy catches in November-February, the most significant in December-January. The areas of spatial correlations between water temperature and anchovy catches increased in period 2008–2021 relative to 1993–2007. The existence of a relationship between the indicator of climate change (water temperature) and fishing parameters in the northwestern part of the Black Sea has been confirmed.
Practical significance: the established long-term correlation patterns between changes in water temperature and the parameters of anchovy fishing in the nortwestern part of the Black Sea allows to increase the efficiency and sustainability of Russian fisheries in these waters.

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