Dolphin kicks

A quite wonderful story at CNN on the development of a prosthesis to aid a dolphin known as Winter who lost her tail:

Recreating one of the most powerful swimming mechanisms in nature turned out to be a lot tougher than expected. But after months of experimenting, Carroll and a unique team of experts are well on their way to, as one of them puts it, "MacGyvering" a tail for Winter.
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She was a frail, dehydrated 3-month-old when she came to the hospital in December 2005. A fisherman found her tangled in the buoy line of a crab trap in Indian River Lagoon near Cape Canaveral. The line cut off the blood supply to her tail and it slowly fell off like shreds of paper as the aquarium team worked to save her life.

Winter learned how to swim without her tail, which is used for propulsion -- amazing her handlers with a unique combination of moves that resemble an alligator's undulating swimming style and a shark's side-to-side tail swipes. Winter uses her flippers, normally employed for steering and braking, to get moving.

But her unique swimming style is sure to lead to spinal problems. She already sometimes bends her spine in an unnatural curve. Trainers work with Winter, now 6-feet-long and a healthy 180 pounds on an extensive physical therapy regimen, bending the tail up and down, to keep the right muscles strong.

Walsh said allowing Winter to work out daily with a prosthetic tail may keep her from deteriorating. It is unlikely she will wear the tail full-time.

It's uncharted territory. Fuji, an elderly dolphin that lives at an aquarium in Japan, has a prosthesis, but it is attached to the remaining part of his tail. Both of Winter's tail flukes and peduncle, a wrist-like joint that allows a dolphin tail to move up and down, were lost.

Winter's team also has to figure out how to keep the prosthesis from sliding off as the tail creates enough force to propel a 400-pound dolphin out of the water and 10 feet into the air.

(Thanks to Atticus for the link.)