Atlantic bluefin tuna reappear in Istanbul Bosphorus and Marmara Sea

Atlantic bluefin tuna have recently been spotted in large numbers across the Istanbul Bosphorus, the Golden Horn, and the Izmit Gulf. Experts suggest this phenomenon is not the discovery of a new habitat, but rather the revival of a century-old migration route.

Associate Professor Taner Yıldız from Istanbul University's Faculty of Marine Sciences noted that these fish are returning to their historical ecological areas. Historical records from the Istanbul Fish Market indicate that during the 1913-1914 season alone, 537,455 kilograms of tuna were sold, demonstrating the species' significant historical presence in the region.

While water temperature is a factor in marine movements, experts emphasize that the migration is also driven by the pursuit of prey, such as bonito, mackerel, and horse mackerel. The return of these massive fish, which can weigh between 100 and 450 kilograms, marks a notable ecological shift in the Marmara Sea.