Invasive species monitoring in the Adriatic Sea

Scientists are monitoring the emergence of non-native species in the Adriatic Sea to prevent ecosystem disruption. Through the ALIENA project, researchers from the Ruđer Bošković Institute and Italian partners are utilizing computer models, molecular methods, and citizen science to develop an early warning system for species that may compete with indigenous life for food and habitat.

A specific focus has been placed on the invasive sea walnut (Mnemiopsis leidyi), a ctenophore from North America. While first recorded in the northern Adriatic in 2005, experts from the Pula Aquarium report that the species has now established stable, reproducing populations. The species poses a threat to the marine food chain by consuming zooplankton and threatens economically important shellfish by consuming their larvae. Environmental factors such as climate change and decreasing oxygen levels may be facilitating its spread by hindering natural predators.

Recent observations from the Institute of Oceanography and Fisheries in Split indicate that the species has been seen in significant quantities in the northern Adriatic since 2016, likely introduced via ship ballast water. The organism has been noted in large numbers along the Istrian coast. While the sea walnut is harmless to humans and does not sting, its spread continues to pose a potential threat to local marine ecosystems.

Despite these ecological risks, researchers have identified potential scientific value in the organism. Its tissues contain antimicrobial peptides and bioluminescent proteins useful for biotechnology and medicine, and it serves as a model for studying animal development and the origins of the nervous system.