Caption provided by photographer Octavio Aburto: Together with my friend David Castro, we were diving with a large group of Bigeye travellies at Cabo Pulmo National Park, Mexico. Thousands of fish forming a ball during the reproduction courtship. In the afternoon, these fish congregate to form a large spawning aggregation around the reefs of the National Park.

Location: Cabo Pulmo, Baja California Sur, Mexico.

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