Captive Whale sharks get health check

Scientists yesterday got a unique opportunity to examine the world's largest fish species, when one of the Georgia Aquarium's Whale sharks had a medical examination.

Ralph, one of the Georgia Aquarium's four captive Whale sharks, underwent the latest in a series of health checks - with the help of 600 gallons of anaesthetic and 50 staff.

According to various reports, a team of 20 divers used nets to guide the 6.7m/22' shark into a giant stretcher that hung from a gantry near the water surface.

A hose was then used to pump hundred of gallons of anaesthetic into the water around the shark's head to keep the fish subdued during two hours of tests.

The Aquarium's Whale sharks have been subject to a series of examinations which started last month.

During the latest procedure the fish was measured and had blood and DNA samples taken so scientists could monitor hormone levels and check that the fish is growing heathily.

An ultrasound machine was also used to examine the health of the shark's internal organs.

The aquarium's first two male Whale sharks, called Ralph and Norton, arrived from Taiwan before the facility officially opened in November 2005. They were joined by a pair of female Whale sharks, named Trixie and Alice, in June this year.

Experts hope that they will be able to learn more about the behaviour, courtship and reproduction of the shark, which is the world's largest fish species.