New Marine Meadows Campaign in the Baltic Sea
Wednesday, 23 Aug, 2023
Sea Shepherd Germany and GEOMAR Helmholtz Centre for Ocean Research Kiel launch a unique cooperation to restore seagrass meadows in the German Baltic Sea.
The campaign is a further development of GEOMAR's successful SeaStore Seagrass Restoration Project, which aims to restore and expand seagrass meadows in the Baltic Sea. For this purpose, GEOMAR is planning another project, the Citizen Science Project, which involves groups and individuals in the planting of seagrass meadows and trains them to contribute actively.
The project started with a joint effort between GEOMAR and Sea Shepherd Germany to develop an online seminar and dive course that will enable divers to harvest and replant seagrass on their own in the future. The project is led by postdoctoral researcher Angela Stevenson, GEOMAR Kiel.
In July, the diving course was tested for the first time in Maasholm with seven divers from Sea Shepherd Germany. Part of our work was to provide both the participants and the necessary equipment and to obtain permits from the relevant authorities. GEOMAR is responsible for the selection of suitable sites and the scientific evaluation of the results, thus ensuring the success of the project.
The First Success
During the first test weekend, 2,500 seagrass plants were already successfully harvested and transplanted to a new location. At the beginning of August, GEOMAR confirmed that the test transplant was successful and that the new seagrass was able to anchor well. The course will now be further optimised and expanded next year.
"Single-shoot transplanting" is the most effective, field-tested method for restoring seagrass meadows. This involves divers planting seagrass shoots one by one. The process is costly and requires a large number of qualified divers. However, the lack of those is currently the biggest bottleneck for a fast and efficient re-greening of the German Baltic Sea. With the help of the project, this need can be met to restore and expand seagrass meadows more quickly and efficiently in the future. By involving citizens, the re-greening of the German Baltic Sea could be achieved more quickly than would be possible by individual institutions.
What makes seagrass so important?
Seagrasses are marine plants that live at depths of about 1 to 8 metres seawater depth in German Baltic Sea waters. The expansion of seagrass is critical to promote the multiple ecological functions of seagrass meadows. Unlike algae, seagrasses have roots and rhizomes, which play a very important role in the long-term storage of carbon. Seagrasses store twice as much CO2 per square kilometre than forests do on land, protect the coast from erosion and supply the seawater with oxygen through photosynthesis. In addition, seagrass promotes biodiversity by providing habitat, shelter and food for many organisms such as fish, nudibranchs, isopods, shrimps, etc. A good example is the spring spawning herring, which need plant substrate, like seagrass to lay eggs. The natural spread of seagrasses through seed dispersal and seedling establishment is often slow (taking decades). Therefore, human-led restoration activities are important to expedite this natural process.
Planting new seagrass meadows offers hope that the poor state of the Baltic Sea can be significantly improved in the future. We will therefore intensify our efforts next year and do our part to protect the Baltic Sea and its inhabitants even more effectively!