The first thing someone feels upon arriving at the Ambracian Gulf is calm. The absence of human presence that could disturb the natural environment is immediately noticeable. The settlements bordering the gulf are sparsely populated, and visitors are few. It takes some time for anyone gazing at the Ambracian Gulf to realize that this place is far from “quiet.” And this “noise” is now… deafening, according to findings from a new study that raises the alarm for this critical marine area and the species it hosts.

Inherently Sensitive Environment

The Ambracian Gulf, a marine area “nested” between three prefectures in western Greece, has many descriptors: ecological sanctuary, site of rare biodiversity, and in recent years, it has earned recognition as one of the most sensitive zones of the Greek marine space, as human activity continuously tests its resilience. In 2008, it was officially designated a National Park, bringing renewed attention to the need for rules and restrictions on activities in the land, freshwater, and marine zones of the area.

Its unique geomorphology—a nearly enclosed gulf—limits water renewal, making it particularly vulnerable to pollutant accumulation. Inputs from agricultural activity, intensive livestock farming, fish farming, and urban wastewater remain in the ecosystem for long periods.

A Significant Survey

Recently, its increasing presence in scientific literature reflects, at the very least, an alarming reality: without effective protection measures, the Ambracian Gulf is rapidly approaching ecological deadlock. A recent study conducted by a team of scientists from Greece, Italy, and Spain, published in the peer-reviewed journal Science of The Total Environment, confirms this.

The study examined rare marine animals for the first time regarding heavy metal levels, specifically mercury, lead, cadmium, copper, and nickel. The research was a collaboration between the Greek environmental organization iSea; the University of Patras; the Universities of Padua, Camerino, and Catania in Italy; the University of the Basque Country in Spain; the International Hellenic University; and environmental organizations from all three countries.

Six species of sharks and rays of different ages—species that live and reproduce in the Ambracian Gulf—were examined. According to Ioannis Giovos, head of Conservation at iSea and lead researcher, “By analyzing 61 samples from adults, juveniles, and embryos, we created the first database for metal levels in the region, which is essential for developing a long-term monitoring and protection strategy.”

One of the key findings was that copper (Cu) shows slightly higher concentrations than expected natural levels, likely linked to agricultural practices and wastewater accumulation. “The elevated copper primarily originates from agricultural activity in the rivers’ catchment areas flowing into the gulf, where copper-based pesticides are used, as well as from biological treatment plant discharges. Both sources are explicitly cited in the literature and in our study as likely main inputs to the Ambracian Gulf,” said Giovos.

Possible Consequences for Humans

Beyond the significant environmental burden on this sensitive ecosystem, the study also warns of potential impacts from increasing heavy metal accumulation on the human body and the broader food chain. While copper is an essential trace element for humans, obtained mainly through diet, excessive levels can be harmful. “In areas where rays are part of the diet, there could be potential future risks for consumers. However, at present, there is no immediate cause for concern for humans, as the copper levels we recorded in species tissues do not exceed safety limits. For mercury, though, estimates suggest that children are near the upper acceptable limits,” explained Giovos.

“Scientific Alliance”

This study was not a standalone effort but the result of coordinated scientific action through the “Alliance for the Ambracian Gulf”, established by iSea and now in its second year. As a collaboration of research centers, the alliance raises awareness and collects scientific data that can be used by the state.

Beyond iSea, participants include the Italian Tethys Research Institute for marine mammals, the Hellenic Ornithological Society, ARCHELON for marine turtle protection, the Oceanus Lab of the Department of Geology at the University of Patras, the Department of Fisheries and Aquaculture of the University of Patras, and the international organization Blue Marine Foundation.

Within this initiative, Oceanus Lab focuses on hypoxic conditions at depths greater than 20 meters. According to Dr. George Papatheodorou, professor at the University of Patras and director of Oceanus Lab,“The gulf can be considered a ‘dead zone’ as there is seasonal hypoxia/anoxia in the western part and permanent anoxia in the eastern part, where the deepest basin lies.”

Using underwater vehicles, Oceanus Lab monitors seabed conditions while mapping critical habitats for the ecosystem.

Urgent Need for Action

The Hellenic Ornithological Society has been active in the Ambracian Gulf since the early 1980s. Magnolia Vougioukalou, Wetlands Program Manager, explained: “The problem our work tries to tackle is the lack of substantial knowledge about species for which the Ambracian Gulf is so important,” emphasizing the urgent need for effective protection measures, noting that hunting is still allowed in areas critical for birds.

Similarly, ARCHELON protects sea turtles (such as Caretta and Green turtles), which rely on the region for feeding and overwintering, according to communication officer Christiana Kamprogianni. These are just some of the parallel efforts protecting this valuable area and benefiting local communities.