EcoTwin Project Showcased at National Ichthyology Symposium: Thracian Sea Case Study

On 31 October, at the 19th Panhellenic Symposium of Ichthyologists in Ioannina, Greece (https://psid.bio.auth.gr/), Dr Konstantinos Touloumis, assistant researcher in Fisheries Research institution (Kavala, Greece), presented the EcoTwin project, an ambitious European initiative linking marine ecology with socio-economic analysis through a “Digital Twin of the Ocean.”

The symposium, themed “Aquatic Ecosystems: Modern Management Approaches,” highlighted the need for holistic, science-based management of aquatic resources. In this context, EcoTwin’s innovative approach drew significant interest, especially as the team showcased its Greek case study focusing on the Thracian Sea in Northern Greece. This case study examines how coastal communities can balance fishing, tourism, and renewable energy development in an ecologically sensitive marine area.

EcoTwin is a Horizon Europe research project (2024–2027) designed to enhance the European Digital Twin Ocean by integrating socio-ecological models.

In simpler terms, it creates a virtual “twin” of real-world coastal ecosystems – combining data on ocean ecology, human activities, economics, and climate – so scientists and policymakers can simulate “what-if” scenarios before making decisions.

The project pioneers new modelling techniques, drawing from graph theory, AI, and network science, to represent complex cause-and-effect relationships between marine life, environmental changes, and human socio-economic factors. By doing so, EcoTwin aims to make vast ocean data (from satellite observations to fisheries statistics) more accessible and useful for everyone, from local communities to government officials.

EcoTwin’s work is being tested in four regional case studies across Europe, one of which is in Greece’s Thracian Sea. The Greek team, led by the Democritus University of Thrace,  and including the Fisheries Research Institute (ELGO DIMITRA), is developing the models in close collaboration with local stakeholders (Use Case Scenarios).

Focus on the Thracian Sea Case Study

The Thracian Sea, part of the North Aegean, is a region where coastal communities have long depended on fishing. However, fishery activity in some areas has diminished due to ecological pressures, overexploitation  and protection measures.

EcoTwin’s Use Case 3, titled “Evaluation of Tourism and Marine Renewables Development Policy on Coastal Communities in the Thracian Sea, Northern Greece,” has a clear objective:

“To assess the potential of tourism and marine renewable initiatives in bolstering the economic prospects of coastal communities, while compensating for diminished fishing activities in the ecologically sensitive areas of the Thracian Sea.” — EcoTwin Use Case Scenarios

In practice, this means the project is exploring how new opportunities like offshore renewable energy (for instance, wind farms) or other marine energy installations and tourism  could support local livelihoods as fishing declines – and whether these can be pursued without harming the marine ecosystem.

A key concern in the Thracian Sea is managing spatial closures – areas that might be closed off to fishing or other uses, either to protect nature or host new infrastructure. The project examines scenarios such as the introduction of offshore wind farms or LNG terminals, looking at their effects on pelagic (open-water) and benthic (seafloor) ecosystems, and on the fisheries that depend on them.

By simulating these scenarios, researchers hope to identify pathways where renewable energy and tourism development can coexist with healthy fish populations and viable fishing communities.

Local collaboration is central to this work. Stakeholders such as the Association of North Aegean Trawlers, fisheries cooperatives, municipal authorities, and researchers from the Fisheries Research Institute (Hellenic Agricultural Organization “Demeter”) are actively engaged, ensuring that models reflect real-world conditions.

Building a “Digital Twin” for Greek Coastal Communities

To tackle the Thracian Sea’s challenges, EcoTwin is developing advanced socio-ecological models, described in the symposium presentation as “complex socio-ecological causal models in the Digital Twin of the Ocean (EcoTwin)”.

In practical terms, this involves:

• Data-Driven Modelling:
  
  The project gathers ecological data (marine species, food webs, water quality), fisheries data (catch records, vessel tracking), and socio-economic data (income, market prices, number of employees, fuel costs) for the Thracian Sea. These feed into a model that mirrors both the environment and local economy.
• Ecological–Economic Linkages:
  
  Using tools such as Ecopath with Ecosim, the team simulates the trophic web of the Thracian Sea (who eats whom in the ecosystem) and overlays this with economic and social interactions, such as how changes in fish stocks affect livelihoods.
  
  The graph-theoretic models developed by EcoTwin combine hard data and qualitative knowledge (for example, fishermen’s local observations), creating a hybrid system that reflects the real complexity of coastal life.
• Participatory Input:
  
  EcoTwin involves local stakeholders through workshops and consultations, so the models evolve with direct input from fishers, tourism operators, conservationists, and policymakers. This participatory feedback ensures the models remain grounded in community experience.
• Climate and Future Scenarios:
  
  The Thracian Sea model also integrates climate change projections, including warming seas and the spread of non-native species. It can simulate how these pressures might affect fish populations and fishing practices, as well as test potential infrastructure changes like port expansions or new terminals.

In essence, the Thracian Sea digital twin serves as a “simulator” for marine policy, allowing authorities to explore outcomes of different strategies virtually before acting in the real world.

Exploring What-If Scenarios for Policy Guidance

One of EcoTwin’s greatest strengths is its ability to support evidence-based policymaking.

Because the Thracian Sea digital twin links ecology with socio-economics, it allows exploration of scenarios that balance environmental conservation with community well-being:

• Offshore Wind Farms vs. Fisheries:
  
  The model can simulate the potential effects of offshore wind farms on marine habitats and fishing grounds, including “foraging sites, biodiversity hot spots, and prime fishing grounds” (EcoTwin Use Case 3). Policymakers can then assess trade-offs and mitigation measures.
• Tourism Development:
  
  By modelling increased tourism activity – such as new marinas or coastal infrastructure – EcoTwin helps evaluate whether tourism can compensate for reduced fishing income, and how it might affect ecosystems.
• Climate Adaptation:
  
  The model also explores climate change impacts, including warming waters and invasive species, in combination with new energy infrastructure and tourism, helping communities prepare for shifts in fish populations and economic conditions.
• Balanced Policy-Making:
  
  The insights from these simulations feed into policy design – identifying strategies that sustain both nature and livelihoods. This aligns with EU goals for a sustainable Blue Economy and Marine Spatial Planning.

The presentation of the EcoTwin project at Greece’s premier ichthyology conference showcased how cutting-edge digital tools can serve traditional coastal communities. The symposium, which gathered more than 350 experts in aquatic sciences, highlighted growing interest in integrated, ecosystem-based management.

By focusing on the Thracian Sea case study, the EcoTwin team demonstrated how ecological science and socio-economic planning can come together to guide sustainable development.

For coastal communities in Northern Greece, this research could inform smarter policies that protect fish populations and marine habitats while creating new opportunities in tourism and renewable energy.

Put simply, EcoTwin is building high-tech predictive tools for our coasts. It doesn’t predict the future with certainty, but it helps us explore how today’s choices shape tomorrow’s seas.

As Greece and the wider Mediterranean face mounting environmental and economic pressures, projects like EcoTwin offer practical, participatory tools for a healthy ocean and thriving coastal communities.