It’s not easy to catch bonefish. Wary of humans, these silvery fish—nicknamed grey ghosts—blend into the sandy flats where they forage and are quick to dart away.

Several species of the fish are found in shallow tropical waters worldwide. To capture one of these eluders, skilled fishers spend years learning how to mimic the movements of bonefish prey, such as shrimp, with their lures. “It’s an absolute art form,” says Matt Ajemian, a fisheries ecologist at Florida Atlantic University’s Harbor Branch Oceanographic Institute. When they do take the bait, “these fish hit hard,” and put up a fight, Ajemian says. “They’re real juggernauts—that's why people love them.”

Their nickname refers not only to their evasiveness but also fits their mysterious