Climate factor in the bioresources dynamics of the Baltic Sea: current data

   The aim of this article: to investigate the infl uence of climatic factors on the dynamics of the main commercial fish species of the Baltic Sea based on current data (through 2025/early 2026), to identify key climatic parameters that determine changes in the structure, abundance and biomass of marine fish populations.

   Methods used: analytical investigations of our own and international databases of oceanographic observations, published works on the issue of environmental changes in the Baltic Sea.

   Fish stock sizes, catches, stock dynamics, and near-term forecasts were obtained based on materials from the Atlantic Branch of the Russian State Research Center of Russian Federal Research Institute of Fisheries and Oceanography (VNIRO) (AtlantNIRO), substantiating the total allowable catches (TACs) of aquatic biological resources in the Baltic Sea, the Curonian Lagoon, and the Kaliningrad (Vistula) Lagoon of the Baltic Sea for 2027 (materials for the state environmental impact assessment), developed by the authors of the article.

   Novelty: a general conceptual scheme of the modern impact of climate change on aquatic biological resources of the Baltic Sea is presented.

   Result: updating data on the impact of climate on the aquatic biological resources of the Baltic showed that the negative consequences of climate change not only persisted, but also intensified. A positive temperature trend (high rates of climate warming) is the main modern factor and at the same time a trigger (and catalyst) of many negative processes that determine the functioning of the entire marine ecosystem.

   Practical significance: in the context of climate change associated when selecting targets and benchmarks on the basis of which the total allowable catch is determined, the role of a truly “precautionary”, scientifi cally based approach and the need to take specific measures to regulate the fishery, taking into account an understanding of current and future risks to aquatic biological resources, have become most obvious.

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