10/04/2026
Our latest dives beneath the surface to the hidden banks of the central Baltic Sea — where life begins on the seabed and rises all the way up the food web.
At Hoburgs bank and Midsjöbankarna, there are no coastlines. Only subtle underwater ridges shaping entire ecosystems far beyond what the eye can see.
💡 Where shallow banks rise from deep basins, light reaches the seafloor & unlocks life in a way that is rare in the Baltic Sea.
🦪 Vast beds of blue mussels act as living engines that filter water, capture energy, and build the foundation for a rich, layered ecosystem.
🐟 Fish like Baltic herring & sprat feed here, carrying this energy across the wider sea.
🦆 In winter, the surface tells the story below: thousands of long-tailed ducks, common eiders & scoters gather — diving deep to reach the seabed’s hidden abundance.
🐬Even the critically endangered harbour porpoise depends on these banks, drawn by reliable feeding grounds shaped far below the waves.
⚠️ But this delicate system faces growing pressures. Increasing shipping noise and climate change threaten the structure that holds this ecosystem together.
🌍 Through protection, monitoring, and international cooperation, efforts are underway to ensure these offshore ecosystems continue to function and to prove that protection delivers real results.
💬 "These banks aren’t visible in the way coastlines are, but they shape life across a much larger area. They influence where food is found, where species gather, and how energy moves through the system. So protecting them isn’t just about protecting a place. It’s about protecting the processes that sustain life far beyond it." - Alexandra Colbing, Marine biologist & MPA Manager at the County Administrative Board of Gotland
👉 Explore the full story at: https://maps.helcom.fi/portal/apps/storymaps/stories/6806242269964a30936eb56c427fd182
Photo credit (harbour porpoises): Solvin Zankl