CLIMATE CHANGE MAY OPEN THE DOOR TO TOXIC FISH IN THE MEDITERRANEAN

Climate change may open the door to toxic fish in the Mediterranean, new study warns. The Pagasitikos Gulf in central Greece has become the focus of an international scientific study published in the journal Geosciences (MDPI), which introduces a pioneering method to forecast the arrival of dangerous invasive species in the Mediterranean.

Researchers from the Department of Agriculture, Ichthyology and Aquatic Environment at the University of Thessaly, in collaboration with the Technical University of Denmark and Ege University in Turkey, have developed for the first time in Greece a computational model capable of predicting the risk of invasion of two of the most threatening species: the toxic silver-cheeked toadfish (Lagocephalus sceleratus) and the lionfish (Pterois miles).

A “radar” for the sea

The innovative model combines statistical analysis, artificial intelligence algorithms and machine learning (including SVM, neural networks and decision trees) with environmental projections up to the year 2035.

This approach acts as a type of “early-warning radar” for the sea, allowing scientists to identify when and where invasive species are likely to appear. Bottom temperature and salinity emerged as the two most critical factors determining the likelihood of establishment.

At present, conditions in the Pagasitikos Gulf remain relatively safe. However, the researchers warn that rising sea temperatures due to climate change could create favourable conditions for invasion within the next decade.

More than a biological issue

The presence of these invasive species is not simply an ecological concern. The silver-cheeked toadfish is extremely toxic and dangerous to public health. Both species also threaten fish stocks, causing significant damage to local fisheries and coastal economies.

Moreover, as highly aggressive invaders, they disrupt Mediterranean biodiversity by displacing native species.

Global implications

The methodology is not limited to the Pagasitikos Gulf. It can be applied across the entire Mediterranean basin, providing a global example of how to manage biological invasions in a rapidly changing climate.

Dimitris Pafras, a PhD candidate at the University of Thessaly and co-author of the study, highlighted the link with climate change:

“Climate change is not an abstract concept. It transforms the very conditions of our seas, creating an environment more suitable for invasive and toxic species. Early prediction and preventive action are essential to safeguard both marine ecosystems and the communities that depend on them.”

The study carries a clear message from the scientific community:

“The sea is changing. If we do not act proactively, invasions will transform not only marine ecosystems but also our way of life.”