Bigeye trevally

Photo: Tsu Soo Tan · CC BY-NC

Schooling predators that form dense, swirling baitballs during the day at cleaning stations and reef edges — one of the most photogenic spectacles on Indo-Pacific reefs. The school rotates slowly, each fish orienting toward the current, creating a living silver cylinder that opens and closes around divers. At dusk, the school disperses and individuals hunt cooperatively across the reef flat. Their large eyes are adapted for low-light feeding. Bigeye trevally are important prey for large sharks and groupers, connecting mid-water and reef food webs.