Unusual Aggregation Of Eagle Rays Around Tuna Cage

A group of critically endangered eagle rays (100-150 individuals) was observed aggregating outside a tuna ranch in Malta, an extremely unusual occurrence. Footage from a remotely operated vehicle (ROV) taken in October 2024 around a tuna ranch off the Northeast coast of Malta in has recorded the largest known gathering to date of this species. A study on their unusual appearance was published in the Marine Biodiversity journal this year.

Researchers said large aggregations of eagle rays are rarely observed. In this case, they highlighted that fresh food used to feed the bluefin had accumulated on the seabed below the cages and the rays were feeding there. Batoid fishes such as rays associating with tuna ranches have been previously documented from the Maltese Islands, the study said.

Picture: ROV footage of eagle rays swimming along the seabed below the tuna cage from which fish are falling.