Atlantic tarpon

Photo: Timothy Mooring · © all rights reserved

Tarpon are one of the ocean's great ancient lineages, with a fossil record stretching back 100 million years. They breathe air directly using a modified swim bladder — an adaptation that allows them to survive in low-oxygen environments like the cavern interior. Schools of 20 to 50 individuals shelter here during daylight, erupting in a chaos of silver when a diver's torch sweeps through them. Tarpon are largely bycatch-free in Nicaragua and remain abundant here.