Seals Use Hidden Caves to Evade Tourists

Why this is here: Seals spent more time in the hidden bubble cave—119 days—than in the larger, more accessible cave during a 141-day monitoring period.

Researchers in Greece observed Mediterranean monk seals using small, underwater “bubble caves” to avoid disturbance from summer tourists. A team led by Julien Pfyffer of the Octopus Foundation studied the seals on the islet of Formicula in the Inner Ionian Sea Archipelago. They installed underwater cameras that recorded the seals resting and sleeping in these secluded chambers, accessible only through underwater passages.

The study, published in Oryx, revealed seals visited the bubble cave on 119 of 141 monitored days. This suggests a clear preference for the hidden space despite its limitations as a habitat. Only about 444 to 600 mature Mediterranean monk seals remain in the wild, and the species is still considered vulnerable.

While the seals are slowly increasing in number, human activity continues to disrupt their behavior. The researchers note bubble caves are not ideal habitats, but they provide crucial refuge. Protecting larger caves and beaches remains the primary conservation goal, but these smaller spaces should also be considered.

The team continues to monitor seal behavior and assess the effectiveness of recent regulations implemented by the Greek government.