After years of scattered sightings, the highly venomous lionfish (Pterois miles) has officially been declared a permanent resident of the Adriatic Sea. This concerning news comes from researchers at the Croatian Institute of Oceanography and Fisheries in Split. Their report indicates an alarming surge in encounters, with 122 sightings recorded along the eastern Adriatic coast between June of last year and January 2025. This rapid spread highlights the species’ remarkable ability to adapt and expand its territory.

The presence of the lionfish poses a significant threat to the local marine environment. As an active predator of small fish, the lionfish has no natural enemies in the Adriatic, allowing its population to grow rapidly. This could lead to a serious imbalance in the delicate ecosystem, impacting native fish populations and potentially harming the region’s biodiversity.

Beyond its ecological impact, the lionfish also presents a danger to humans. Its spines are venomous, and a sting can cause severe pain, swelling, and in some cases, serious complications. Prompt medical attention is necessary if someone is stung by this invasive species.

Authorities and researchers are now facing the challenge of managing this new permanent resident in the Adriatic Sea. Understanding its rapid spread and developing strategies to mitigate its impact on both marine life and human safety will be crucial in the coming years.