February 29, 2008—A three-year-old green sea turtle with only one flipper may be the first sea turtle to be fitted with a prosthetic appendage.
The turtle was found in 2005 with fresh predator wounds, probably from a shark, said Jeff George, a curator at Sea Turtle, Inc., a South Padre Island, Texas-based turtle rescue organization.
Now the University of Texas Dental Branch in Houston is molding the artificial flipper, experimenting with different types of silicon to determine which has the most appropriate density, George said.
The flipper may have to be replaced every five or ten years, depending on how it is attached to the growing turtle, he said.
Some green sea turtles are believed to live well over a hundred years in the wild, and they grow slowly.
Named Allison, the turtle currently weighs 18 pounds (8 kilograms), and she could grow to 550 pounds (250 kilograms), George said. Her keepers will be able to control her growth rate, to some extent, by limiting or increasing her food.
Green sea turtles can live in captivity with two flippers and are routinely released into the wild if they have three of their original four flippers, George said. But those with one flipper can't swim properly and don't usually survive.
"We're not even thinking of releasing this turtle," George said.
Other marine animals have worn prostheses successfully. For example, a dolphin in Japan was outfitted with an artificial tailfin, according to scientists at Okinawa Churaumi Aquarium who have made improvements to the fin since the first model was attached in 2003.
George said a mold will be taken of Allison's stub in the next few weeks, and he expects the prosthetic flipper will be attached by spring or summer.
"We have absolutely no documentation of a prosthetic flipper for a sea turtle before," he said.
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