That’s what photographer and Nat Geo Explorer Erika Larsen kept wondering as she worked to show the gentle grazers of the sea (above, a ribbon of eelgrass in the mouth of a manatee). At dark, from Florida’s Crystal River, she could hear them, “these gusts of breath.”

“We began calling them ‘the sounds of the ancients.’” What’s being done to save them?

See the full story here.

Please consider getting our full digital report and magazine by subscribing here.