Dolphin’s peculiar fin is proof it has been living off Charleston, SC, for 23 years

Telling dolphins apart isn’t easy, but experts in South Carolina say they have definitive proof the same stubborn mama dolphin has been living off Charleston for 23 years running.

The dolphin, named Floppy, is unmistakable because she has a unique dorsal fin that curls like a hook as it sticks above water, according to the nonprofit Lowcountry Marine Mammal Network.

“This can be the result of a birth defect, injury or deficiency,” the network posted Sept. 24 on Facebook. “Good news is, she’s been monitored in Charleston since 1996 and often with calves... The flopped fin has not had any negative effects on reproduction.”

Floppy, who is currently mothering a calf, is known to frequent the rivers near Charleston, where she “strand feeds,” according to Lauren Rust, executive director of the Lowcountry Marine Mammal Network.

“Strand feeding” is a unique ritual in which coastal dolphins herd smaller fish toward shore, then leap from the water to snap them up in a frenzy of splashing.

The Charleston area is believed to have 350 “resident dolphins” that linger in its river systems, including Floppy and her calf, Rust told McClatchy news group.

“Floppy has had that fin as long as she’s been monitored. Dolphins can live 25 to 40 years,” she said.

“Our resident dolphins live longer than offshore, migratory dolphins because they have an easier life. Good food, less traveling. At one time in Charleston, we had a dolphin on record at 41 years old. If it’s still alive, it would be 42-43 by now.”

Marine biologists must often rely on unique marks in a dolphin’s dorsal fin, including scratches and nicks, to tell them apart from a distance, the network says. Using those marks, experts have been able to create a “sighting history” for many of the dolphins near Charleston, says the network’s website.

This story was originally published September 26, 2019 at 3:12 PM with the headline "Dolphin’s peculiar fin is proof it has been living off Charleston, SC, for 23 years."