Glassfish

Photo: Roberto Pillon · CC BY-NC

Atherina boyeri aggregates in the thousands inside the Elephant Cave entrance, using the sheltered chamber to escape open-water predation while feeding on zooplankton entrained by gentle tidal flow. The schools are so dense they create visible silver columns visible from outside the cave on sunny days, and their collective movement creates a dazzling baitball effect when divers move through the chamber. Larger predators including sea bass and grouper cruise the cave entrance at dusk to intercept glassfish leaving to feed in open water, making late-afternoon dives particularly dramatic.