Rare sharks and bluefin tuna spotted in the Belgian North Sea

Researchers from the Flanders Marine Institute (VLIZ) reported highly unusual marine sightings in the Belgian North Sea during late September 2026. Scientists captured three juvenile smooth-hound sharks approximately 23 kilometers off the coast. Two of these specimens, measuring 55–60 cm and aged roughly 2.5 years, were fitted with transmitters to track their migratory patterns.

This discovery is significant as no smooth-hound sharks had been recorded in ILVO trawl surveys since 1985. The species is classified as ‘vulnerable’ in Europe and ‘critically endangered’ globally, having seen a 76% population decline in European waters over the last 80 years due to overfishing and bycatch.

Additionally, a maintenance technician at an offshore wind farm observed 3–4 Atlantic bluefin tuna jumping from the water. This represents the first unconfirmed sighting of the species in the region since the 1960s. The shark research is part of the ELASMON project, a collaborative effort between ILVO, VLIZ, and the Royal Belgian Institute of Natural Sciences to monitor sharks and rays to inform conservation measures.