Virus suspected in fish die-offs along island shores

Alarming numbers of dead groupers and other fish have been found along the southern coast of Crete, Andros, Tinos and Syros since early September.

Investigations led by the Hellenic Center for Marine Research (HCMR) point to a viral culprit, Betanodavirus, which is known to affect species like dusky groupers (Epinephelus marginatus) but is harmless to humans. 

Reports from Crete and Andros indicate unusual fish behavior, including lethargy and disorientation near the water’s surface.

Local fishermen, who first noticed the phenomenon, also report other signs consistent with the virus, which impacts the fish’s nervous system and swim bladder, impairing balance.

While similar die-offs have occurred before, the scale this year is unusually large, prompting further analysis into possible viral mutations.