Early explorers often mistook manatees for mermaids. Up to 4 meters long and weighing half a ton, the portly aquatic creatures are closely related to elephants.

After being driven almost to extinction, manatee populations in Florida have increased fivefold since 1991 as a result of conservation efforts.

Did you know?

The West Indian manatee lives in the Atlantic Ocean, Gulf of Mexico and Caribbean Sea. Within the United States, West Indian manatees are found primarily in Florida, especially in the winter, when they seek warmer waters. In summer months, they can be found as far west as Texas and as far north as Massachusetts.

Manatees spend most of the day grazing on aquatic grasses, eating up to 10 percent of their body weight daily.

Manatee swimming underwater with fish (Ramos Keith/USFWS)
(Ramos Keith/USFWS)

Up for air

Manatees can hold their breath for up to 20 minutes at a time. But they usually surface for air every three to five minutes.

When they breathe in, they replace 90 percent of the air in their lungs. Humans, on the other hand, replace about 10 percent with each breath.

Manatee taking breath at water's surface (Tracy Colson/USFWS)
Manatees are mammals and must surface to breathe. (Tracy Colson/USFWS)

Manatees need warmth

Manatees need warm water to survive. When temperatures drop below 20 degrees Celsius, they suffer from dangerous “cold stress.” In winter, manatees often congregate in warm, spring-fed rivers.

Manatees swimming in group (© AP Images)
(© AP Images)

Manatees and humans

Manatees have no natural predators, except maybe humans. Fishing lines, the slicing propellers of motorboats and the pressures of development devastated manatee populations, pushing them to the brink of extinction. Their numbers were so low, manatees were one of the first animals protected in 1966 under the predecessor of the U.S. Endangered Species Act.

“It’s hard to imagine the waters of Florida without them,” said Michael Bean of the U.S. Department of the Interior. “But that was the reality we were facing.”

Manatee underwater with scars on its back (Robert Boone/USFWS)
A manatee shows scars on its back from motor boat propellers. (Robert Boone/USFWS)

Back from the brink

Thanks to U.S. federal and state conservation efforts to slow down boaters, manatee populations are starting to flourish in Florida. In 1991, aerial surveys spotted only 1,200 manatees in Florida waters. In 2016, that number increased to more than 6,000.

Because of this rebound, biologists at the U.S. Fish and Wildlife Service have proposed listing West Indian manatees as “threatened” rather than “endangered” under the Endangered Species Act. This would reflect a species not in immediate danger of extinction, but would not remove any of the regulations protecting manatees, according to scientists.

“The manatee’s recovery is incredibly encouraging and a great testament to the conservation actions of many,” said Cindy Dohner of the Fish and Wildlife Service.

Baby manatee being held and fed with bottle (USFWS)
An orphaned manatee is nursed back to health. (USFWS)