by croatiaweek
February 22, 2026
in
Illustration
22 February 2026 – An intriguing sighting has been reported this week off the coast of Cres, after a follower submitted video footage of a large shark cruising through the Adriatic Sea to Blue World Institute.
Although the video quality was not entirely clear, experts have concluded from the distinctive shape of the dorsal fin that the animal is most likely a basking shark (Cetorhinus maximus), the second-largest shark species in the world.
A Rare but Regular Visitor
The basking shark is considered rare in the Adriatic, yet it is consistently present along the eastern Adriatic coast. Most documented sightings occur in the northern Adriatic, particularly in the Kvarner Gulf, an area recognised for having the highest zooplankton biomass in the Adriatic Sea.
Zooplankton forms the primary diet of the basking shark. This migratory species feeds by swimming slowly with its enormous mouth wide open, filtering plankton from the water. Despite its formidable size and appearance, it poses no danger to humans.
Growing to lengths of more than 10 metres, the basking shark is second in size only to the whale shark. Its sheer scale often surprises those fortunate enough to encounter it.
Citizen Reports Aid Marine Research
Marine researchers have expressed gratitude to members of the public who continue to share valuable footage and reports.
Public observations play an increasingly important role in monitoring the presence and movements of marine species across the Adriatic.
Those wishing to report sightings of marine mammals and other notable sea life can do so via the free Marine Ranger mobile app (www.marine-ranger.org), through Blue World Institute’s Facebook page, or by emailing [email protected].
By contributing photographs, reports and app entries, members of the public provide crucial data that supports scientific research and conservation efforts.
Each submission helps build a clearer picture of marine biodiversity in Croatian waters and strengthens efforts to protect the Adriatic’s delicate ecosystem.
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