As an invasive species, lionfish have swept across the Mediterranean Sea like wildfire, threatening the balance of ecosystems across the region as they went. Conservation efforts have been working to remove them, but a new study published in the Journal of Fish Biology indicates that their removal could now be impossible, making invasive and predatory lionfish a permanent resident of the Mediterranean Sea.
The study focused on the lionfish Pterois miles, which was first spotted as a foreign invader in Cyprus in 2012. Since then, these immigrants have thrived, and in 2018 groups of up to 70 lionfish were found loitering in the shallows and around reefs. Part of their success centers around their quick maturation time of just one year, after which the adults are capable of spawning year?round. However, the unfortunate boom in their numbers is thought to be in part caused by a peak in spawning, which is brought on by the summer sea?surface temperatures, which reach around 28.4°C (83.12°F).
"Among the numerous threats to our marine ecosystems, biological pollution is less apparent to the human perception. But in reality, it's potent enough to disrupt the ecological balance," Savva Ioannis, the publication's lead author and a researcher from the Marine and Environmental Research, said in a statement. "Although not all alien species successfully establish in or harm their new environment, some acclimatize relatively easy, exhibit rapid spread and exert catastrophic impacts on local marine communities. That has been the case with lionfish populations in the western Atlantic Ocean and now the story is repeating itself in the Mediterranean Sea."

Pterois miles were first seen off the coast of Cyprus in 2012, the species is now thriving and well-established in the area. Marine and Environmental Research (MER) Lab
Lionfish aren’t fussy and will predate on a wealth of fish and crustaceans, the victims of which are often valuable catch for fishermen or represent keystone species in an ecosystem. One solution to halt their spread outlined by the researchers is the development of a dedicated lionfish industry. They hypothesize that by rebranding lionfish as an appealing food source, we could effectively “fish” our way out of the invasion and get a hold on the unfolding situation. Their invasion across the globe has prompted the invention of novel robotics and inventive recipes. So, who knows, perhaps one day lionfish will become a sushi staple?
The invasion of lionfish across the Mediterranean is thought to pose a serious threat to the balance of marine life in the region if nothing is done to stem the spread, as lionfish top the charts as the most damaging invasive fish species known to science. The researchers conclude that the study should serve as an indication of the need for biosecurity measures in the Suez Canal, Egypt, which acts as a corridor through which such invasive species can access the Mediterranean Sea.