Activity category: Vulnerable species
Year: 2022
Type: Advocacy, Scientific research
Status: Ongoing
Target areas: Argosaronic Gulf
Target organisms: Posidonia
Project website:
Activity category: Vulnerable species
Year: 2022
Type: Advocacy, Scientific research
Status: Ongoing
Target areas: Argosaronic Gulf
Target organisms: Posidonia
Project website:
Objectives
The project aims to understand the distribution of the seagrass meadows Posidonia oceanica and other marine seagrass species in the Argosaronic Gulf. Through mapping and identifying the threats these marine ecosystem face, the project seeks to establish a baseline to support the future management and conservation of the area. In addition, through targeted awareness-raising and communication actions, iSea aims to inform the wider public about the value of this important habitat and the significance of its conservation, in collaboration with the local community.
Description
The Argosaronic Gulf is an area known for its natural beauty and, due to its location and its proximity to Attica, is considered one of the most popular destinations. However, intense tourist activity poses threats to the marine ecosystem and to Posidonia, including pollution (wastewater, litter) and mechanical damage caused by uncontrolled anchoring. Within the framework of the Reposidonia program, iSea has started operating in the area with the aim of mapping the priority habitat Posidonia oceanica and identifying the emerging threats it faces. In 2022, the mapping of Posidonia meadows was conducted for the first time around Spetses, Spetsopoula and Velopoula, while in 2023, the actions were extended to Hydra Island. In 2024, the project focused on mapping Posidonia meadows in the area of Poros Island and Methana Peninsula while exploring the historical presence of seagrass meadows in relation to both current and past aquaculture facilities (active and abandoned). In 2025, the mapping of marine seagrass will continue in the area of Argolic Gulf in association with existing or aquaculture development areas, combined with further exploration of the historical presence of seagrass near these facilities.
Results
The data collected were organized into databases, and distribution maps were produced, which can be used by relevant authorities for conservation and management purposes. In addition, the results of the program contributed to strengthening scientific knowledge about the ecological importance of Posidonia meadows in the Argosaronic, highlighting their role as biodiversity hotspots, nursery areas, and natural blue carbon sinks. Through information and communication activities, the findings were shared with the wider public and local communities, enhancing understanding of the value of seagrass beds and the importance of active participation in their protection.
In 2025, the mapping of marine seagrass continued in Argolic Gulf in association with existing and development aquaculture areas. While the previous years, seagrass mapping was focused only on Posidonia, this year, there were efforts extended to the mapping of another seagrass, Cymodocea nodosa, where high-quality maps were produced for both Posidonia and Cymodocea. The mapping resulted in 18.29 ha mapped meadows with 91% accuracy. Furthermore, the actions were combined with the exploration of the historical presence of seagrass near these facilities, concluding to a percentage of loss of this habitat. When looking at the proposed aquaculture expansion plans, the results of this year’s study suggest that at least two facilities could affect seagrass health, considering their distance to live meadows. In light of further increases in production, it is important to identify the correct status of the area and avoid any further damage to surviving seagrass meadows, key to supporting wild fish populations. Considering the known impacts, the closed characteristics of the Argolic, demands from local community, alternatives should be addressed.