A sunken World War II hospital ship off the coast of Albania has attracted both invasive devil firefish and rare Mediterranean monk seals, leading researchers to weigh the risks and benefits of these wrecks for local ecosystems.
The ship, called the Po, sank off Vlora Bay in 1941 after being hit by a torpedo from a British Fairey Swordfish aircraft during the Greco-Italian War, one of the conflicts within World War II. It is now acting as an artificial reef, with over 80% of its surface teeming with marine life, researchers reported July 27 in the journal and into the Adriatic Sea due to warming global temperatures. Modugno said she expects a “serious problem” involving the devil firefish within the next 10 years.
“For at least three years, I’ve observed a steady and unstoppable increase in fish such as Pterois miles along the Albanian coast, as well as other invasive plant species, mollusks, and shellfish, as well as the spontaneous return of the Mediterranean monk seal,” Modugno said. “Now, the Albanian coasts are experiencing constant overgrazing, just like the Greek and sub-Italian coasts, and the lionfish population is literally exploding.”
The study confirmed that this was one of the northernmost reported occurrences of the firefish in the Adriatic Sea.
However, invasive species aren’t the only ones attracted to these shipwrecks. The researchers also noted 28 fish species living around the wreck, egg clusters belonging to the Ommastrephidae family of squid, and even sightings of the rare Mediterranean monk seal (Monachus monachus).
Most notably, researchers captured a monk seal resting within the sheltered cavities of the wreck in August 2023, which was the first confirmed sighting of the species in Vlora Bay since 1996.
This monk seal species typically breeds in sheltered sea caves across Mediterranean beaches. However, tourism and other human activities have forced the species into more isolated and dangerous caves. This, along with other threats from fishing entanglement, continue to threaten the seals. The sighting indicates that monk seals are using these artificial reefs as potential resting opportunities when their natural habitats are fragmented, the researchers said in the study.
