Baltic Sea -

Key indicators for fish stocks, waterbirds, and marine mammals have failed to meet health thresholds. The Baltic harbour porpoise population is critically low, with only about 500 individuals remaining.

Approximately 94% of the sea is impacted by excessive nutrients, leading to "dead zones" roughly 1.5 times the size of Denmark. baltic sea

State of the Baltic Sea – Third HELCOM holistic assessment Key indicators for fish stocks, waterbirds, and marine

In early 2026, experts noted a rapid loss of water (275 billion tonnes), leaving levels 67 cm below average due to atmospheric factors. Maritime & Economic Activity State of the Baltic Sea – Third HELCOM

The is currently classified in "poor environmental status," as detailed in the comprehensive State of the Baltic Sea 2023 report. While regional efforts have successfully reduced nutrient inputs in some areas, the overall ecosystem remains under severe pressure from eutrophication , pollution , and climate change . Environmental Status & Ecology