With about 20 new ones non-native animals and plants oceans discovered annually in European waters, and as many as 70% of them are in the Mediterranean Sea. Oceanologists are now investigating the consequences of these invaders.
Two years ago, in the idyllic waters of Madeira, home to 70 non-native species, researchers came across a disturbing discovery: a brown algae called Rugulopteryx okamurae.
João Canning-Clode is chairman of the Invasive Species Expert Group at ICESthe International Council for the Exploration of the Sea.
He describes this discovery of algae as unprecedented and points out its rapid spread and ‘pest behavior’. These invasive algae not only cover beaches with their unsightly presence, but have also become a bane for tourists and a headache for local authorities, as well as for those who dive deeper into the ocean.
Despite attempts to reuse it as a fertilizer, its stubborn resilience underlines the challenges this poses non-native species.
It’s not just algae that’s causing problems, there are also a number of invasive fish causing problems in the troubled waters of the Mediterranean.
Voula Karachleresearch director at the Hellenic Centre for Marine Researchexposes some notorious invaders, including the poisonous silver-cheeked toadfish, Lagocephalus sceleratus.
Despite its harmless appearance, it harbors a deadly secret: its flesh is laced with toxins, making it a potentially lethal choice for human consumers.
“We had some incidents, like in Greece and Cyprus, where… they didn’t know what it was. They ate it. And then they were hospitalized as a precaution,” Karachle said.
In the eastern Mediterranean, she said, about 28 people have died after eating it.
What is the difference between non-native and invasive?
According to Canning-Clode, the key lies in their behavior. While non-native species simply indicate organisms found in new locations; Invasive species are species that exhibit harmful ecological and economic impacts.
However, fighting these invaders proves to be an almost Herculean task, and in some cases the battle is more reminiscent of Sisyphus and his rock. Unlike terrestrial ecosystems, where containment is feasible, vast marine environments pose enormous challenges.
“When we talk about the aquatic environment and especially the seas, there are no boundaries,” says Canning-Clode. “There’s always a delay… before we notice it, and in the cases where we have noticed it, it may already have gone beyond our means. [of solving the issue].”
Where possible, prevention is much better than cure, and prevention only happens through early detection and intervention. Eradication efforts often prove futile, as evidenced by the failed attempts in the US Azores.
“Our colleagues in the Azores found green algae in the harbor of one of the islands, and they have spent more than €1 million eradicating it, with many divers using copper blankets and other methods,” Canning-Clode explains. .
“They had no success and stopped. It’s really difficult,” he laments. “Our main goal should be prevention.”
So, where do we go now? In the fight against invasive species, cooperation appears to be our most important weapon. By promoting synergies between scientists, policymakers and laypeople, it is easier to strengthen prevention efforts and develop robust mitigation strategies. Early detection, coupled with rapid action, could be the key to stem the tide of invasive species and preserve the country’s rich biodiversity Mediterranean.
Additionally, there is another solution that you may not have thought of yet.
Beat ’em or eat ’em: a more unusual solution to the problem
“If we can’t beat them, we have to eat them,” Karachle explains, “they are edible. They are tasty.”
If you exclude the puffer fish of course.
She and her team examined four invasive species in the Mediterranean Sea and found that they are extremely rich in essential fats. Her goal now is to encourage fishermen to catch them and see these creatures scaled up in the industryturning them into “smoked, salted, canned, jerky” products.
While many fishermen and industry experts already agree with these species, “consumers are another problem,” she says.
The solution? “We have launched campaigns such as having celebrity chefs, cooking them, providing recipes to people online and organizing events in restaurants,” Karachle enthuses.
If the thought of eating these fish doesn’t appeal to you, there are other options: carrying invasive species as a handbag.
“My friend Aylin Ulman in Turkey has set up a small company and she is taking over the leather. And they produce extremely beautiful clutches and wallets, says Karachle. Ulman is the brains behind it Puffer fish leatherwhich uses invasive but not endangered species to create these unusual creations. In addition to using these fish, they emphasize improving their ecological footprint, as well as practicing sustainable fishing practices and eco-friendly tanning processes.
Canning-Clode, however, is slightly less enthusiastic about that prospect.
“I think I have a more conservative view,” he says. “There are positive uses of non-native species, but I think the positive benefits of invasions do not outweigh the negative consequences.”
To learn more about the Mediterranean’s myriad invasive creatures, listen to the full episode of Ocean Calls in the player above.
In this episode of Ocean Calls, we explore the truth behind these alien species – and how we can best deal with them.
We will call on the expertise of João Canning Clode, chairman of the Invasive Species Expert Group at ICES, the International Council for the Exploration of the Sea, and Voula Karachle, an expert on invasive species from the Hellenic Center for Marine Research.
At the end of the episode you will hear the story of Amjad Almatni, a young Syrian activist from the drought-stricken area of Syria, about the magical moment he saw the ocean for the first time in his life.
Ocean Calls is produced in collaboration with the European Commission’s Directorate-General for Maritime Affairs and Fisheries.