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Updated 26 May 2026 - Bornholm, a remote Danish island in the Baltic Sea, grapples with ecological collapse and rising geopolitical tensions as pollution and Russia's shadow fleet heighten risks to its fragile marine ecosystem.
Collapse of a fishing industry
Bornholm's once-thriving fishing sector has vanished. Tom Nielsen, the island's harbourmaster for 27 years, recalls a bustling port where 55 boats docked simultaneously, supporting hundreds of jobs in processing, mechanics, and trade. Today, only one commercial vessel remains. The 141-year-old fishermen's association dissolved in 2024 after a 2019 ban on cod fishing due to stock collapse.
"It was a shock when the fishing disappeared," Nielsen says. "There are still no fish." Scientists estimate the Baltic's recovery could take over 400 years-or may never occur-due to overfishing, oxygen depletion, and warming waters.
Dead zones and algal blooms
Human pollution from fertilizers and sewage fuels algal blooms that suffocate marine life. When algae die, their decomposition depletes oxygen, creating "dead zones" that now cover areas larger than Denmark or Ireland. Marine biologist Marie Helene Miller Birk, co-founder of environmental charity Ivandet, describes a white "corpse sheet" of dead matter spreading across the seafloor, increasingly visible near Bornholm's shores.
"The Baltic looks beautiful," Birk says. "That's the biggest problem-people don't see the crisis beneath the surface."
Geopolitical risks and Russia's shadow fleet
Russia's invasion of Ukraine in 2022 spawned a "ghost fleet" of aging tankers evading Western sanctions. Environmentalists warn these poorly maintained vessels risk catastrophic oil spills in the Baltic's shallow, enclosed waters. Russian authorities deny negligence, but Annamari Arrakoski-Engardt, CEO of Finland's John Nurminen Foundation, calls the fleet "the biggest threat" to the sea's survival.
The Baltic Marine Environment Protection Commission (HELCOM), which includes Russia, reports reduced oil spills since 1989 but notes cooperation has stalled since 2022. The nine non-Russian members (H9) suspended formal talks, citing "business as usual" with Moscow as untenable. "Contacts are greatly diminished," says HELCOM's Rüdiger Strempel. "We receive no data from Russia."
Pollution and climate pressures
The Baltic's unique geography-shallow, brackish, and slow to flush-exacerbates pollution. Nine rivers drain into the sea, carrying nutrients from 90 million people across 14 countries. Eutrophication affects 97% of the Baltic, while hazardous substances, plastics, and wartime munitions further degrade ecosystems. Climate change compounds these threats, raising temperatures and shrinking biodiversity.
Grassroots efforts, like the 2024 Save the Baltic Sea hiking expedition, aim to mobilize public action. The John Nurminen Foundation's gypsum soil treatments cut phosphorus runoff by 50%, while HELCOM's action plan has reduced nutrient pollution. However, Strempel cautions: "Full restoration is likely impossible."
Hope amid crisis
Despite the challenges, activists like Birk and Magnus Heide Andreasen, co-founder of startup Redox, refuse to abandon the Baltic. Redox is developing technology to reverse oxygen depletion, though details remain confidential. "I couldn't live without hope," Andreasen says. "But the Baltic won't return to what it was 150 years ago."
Birk's charity, Ivandet, turns a former ice factory into a hub for education, using hands-on activities to reconnect locals with the sea. "The Baltic isn't dead," she insists. "We must see the opportunities it still offers."
Russia's response
The Russian embassy in London stated: "Russia remains committed to the Helsinki Convention and continues to participate in HELCOM. Western allegations about the 'shadow fleet' are hypothetical, while documented environmental damage receives less attention."
