Cod distribution in the Barents Sea under climate changes

Abstract

The aim of the paper is to assess the impact of climate changes and oceanographic conditions on the distribution of cod stocks in the Barents Sea in recent decades. The material for the study was oceanographic data obtained during surveys in the Barents Sea by PINRO and other available information on hydrometeorological conditions of the sea in 1981–2021, as well as data onRussian catches of cod in the Barents Sea based on bottom trawl fishing operations. Methods of descriptive statistics as well as comparative, correlation and regression analyses were applied. Results: The modern changes in the climate and oceanographic conditions of the Barents Sea are described. Since the early 1980s, the warming has been observed against the background of increasing storm activity, having peaked in 2016. After that, despite still warm and low-ice conditions, there has been a cooling trend in the Barents Sea. Under climate changes in recent decades, cod made increasingly long migrations north and east, spreading more widely in the feeding areas. The most informative predictors in assessing the impactof climate changes and oceanographic conditions on the distribution of cod stocks in the Barents Sea were Arctic ice extent, area-averaged temperature at a depth of 100 m, Atlantic water area in the 50–100 m layer, and parameters of the Barents Sea thermal frontal zones. Practical significance: The obtained results are useful for a better understanding of the processes occurring in the Barents Sea ecosystem and, in the future, will be used to predict cod distributions in the sea, depending on oceanographic conditions and climate changes.