In 2021, researchers began placing concrete-block oyster reefs on Prince Edward Island; biomass rose 45-fold

Representative Image (AI-generated) What started as piles of concrete blocks on the seafloor off Prince Edward Island soon became a magnet for marine life. Researchers began installing the artificial oyster reefs in 2021 to test whether they could provide some of the ecological functions lost from areas where eelgrass no longer grew. Within two years, the structures had been colonised by 45 taxa, while biomass was about 45 times higher on two-year-old reefs than on newly installed ones. The findings, published in Ecosphere, show how a simple structure can provide a new foothold for marine life in a fragmented coastal habitat.Turning bare seabed into new habitatThe work took place on the eastern end of Lennox Island, Prince Edward Island, where eelgrass (Zostera marina) meadows are broken up by patches of bare sediment. Instead of trying to plant eelgrass directly into those empty areas, researchers tested another idea. They built small artificial reefs from ordinary concrete blocks and placed them in the bare patches.The first 18 reefs went into the water in July 2021. Another 16 were added in 2022, followed by eight more in 2023. Each reef was made from eight to 10 concrete blocks...