A WWII Hospital Shipwreck Is Now Shelter for Firefish and Monk Seals

A sunken World War II hospital ship off Albania has developed into an underwater refuge for a surprising mix of marine life, including invasive devil firefish and a rare Mediterranean monk seal. The ship, named Po, sank in Vlora Bay in 1941 after a British Fairey Swordfish aircraft torpedoed it during the Greco-Italian War. According to research reported in the journal Frontiers in Ocean Sustainability, more than 80% of the wreck’s surface is now covered or occupied by marine organisms, making it an artificial reef. The study examined the wreck between June 2022 and September 2024. Researchers recorded 28 fish species around the ship, along with squid egg clusters from the Ommastrephidae family. They also observed as many as seven devil firefish—also known as lionfish—at one time. Devil firefish are native to warm waters of the West Indian Ocean and the Red Sea. Their presence near Albania represents one of the northernmost reported occurrences of the species in the Adriatic Sea. The researchers suggested that wrecks may help attract invasive animals into temperate waters by providing shelter and surfaces where algae and other food sources can grow. The study placed the firefish sightings within a broader pattern of species moving from the Red Sea through the Suez Canal toward the Adriatic as waters warm. Simone Modugno, a University of Ferrara biologist and study co-author, said the Albanian coast had experienced rising numbers of devil firefish and other nonnative species, alongside unusually high temperatures and persistent heat extremes. The wreck has also provided shelter for a species conservationists rarely see in Vlora Bay. In August 2023, researchers recorded a Mediterranean monk seal resting inside one of the ship’s protected cavities. It was the first confirmed sighting of the species in the bay since 1996. Mediterranean monk seals usually breed in sheltered sea caves, but tourism and other human activity have pushed them into more isolated locations. Fishing entanglement remains another threat. The researchers said the seal’s use of the Po suggests that artificial reefs may offer resting places when natural habitat is fragmented, even as the same structures can support invasive species.