Malta’s Bays: Invaded by Alien Species

Imagine diving into the crystal-clear waters off Malta’s coast and finding yourself in a scene straight out of an alien movie. That’s the reality marine biologist Dr. Alan Deidun is warning us about. The bays that once teemed with vibrant marine life are now becoming ‘alien worlds’, he says, as invasive species outcompete native ones, transforming our underwater landscapes.

An Unseen Invasion

Malta’s waters, once a rich mix colour and life, are now hosting an increasing number of invasive species. These unwanted guests, hitching rides on ships’ hulls or in the ballast water they carry, are outcompeting native species for resources and space. The result? A dramatic shift in the makeup of our marine ecosystems.

Take the case of the invasive lionfish, for instance. Native to the Indo-Pacific, this venomous fish has found Malta’s waters to its liking. With no natural predators here, its population has exploded. They’re now a common sight in bays like St. Peter’s Pool in Marsaxlokk, where they’ve driven out many native species.

Familiar Bays, Unfamiliar Faces

But it’s not just lionfish. Other invaders like the golden jellyfish, the northern krill, and the fanworm are also making their presence felt. These species, once rare or non-existent in Maltese waters, are now common sights. Meanwhile, native species like the seagrass Posidonia oceanica and the critically endangered angel shark are in decline.

Dr. Deidun, who has been studying Malta’s marine life for decades, is alarmed by the pace of change. “I’ve seen bays I’ve dived in for years become almost unrecognizable,” he says. “It’s like they’ve been colonized by alien species.”

What Can We Do?

So, what can be done to halt this alien invasion? Dr. Deidun believes education and awareness are key. “We need to teach people about the issue, so they understand our native marine life,” he says. “And we need stricter controls on ships’ ballast water to prevent more invasive species from arriving.”

Local initiatives are already underway. The Malta National Aquarium, for instance, is raising awareness about invasive species through its educational programs. Meanwhile, the Ministry for Fisheries, Aquaculture and Animal Rights is exploring ways to control invasive species and protect native ones.

But it’s not just up to the authorities. Every diver, every snorkeler, every beachgoer has a role to play. By reporting sightings of invasive species, by being mindful of our impact on the marine environment, we can all help preserve Malta’s underwater heritage.