Scientists Spot A Way To Put Bite On Sharks' Extinction

October 10, 2005

Release from: Andrea Mayes
The Australian

A new method of identifying and recording individual whale sharks could help save the giant fish from extinction.

Scientists have discovered that the sharks -- considered a threatened species internationally -- can be tracked by the unique patterns of spots on their skin.

The new technique involves photographing an area of their skin behind their gill slits and feeding the images into a special computer program that can distinguish the subtle differences between them and identify in dividual sharks using pattern-recognition tools.

Developed by Australian marine biologist Brad Norman, together with NASA astronomer Zaven Arzoumanian and US software expert Jason Holmberg, the program is based on the software used by NASA in the Hubble space telescope to map the stars in the galaxies.

"The white spots and markings on the dark skin are like constellations of stars, and the Hubble's program has been adapted to deal with photos of these markings on whale sharks," Mr Norman said.

It was hoped the program would prove to be a valuable conservation tool, allowing researchers to track whale sharks and help understand their migratory patterns.

"We hope it's going to help us get an understanding of their numbers, " Mr Norman said.

Until about 10 years ago, very little was known about whale sharks, and it was not until 1996 that researchers discovered they gave birth to live babies instead of laying eggs.

"There has been a greater awareness of whale sharks over the past few years, and we've started to see an eco-tourism industry built around them in some parts of the world," Mr Norman said.

"We are trying to encourage countries like Taiwan to go down the route of eco-tourism instead of hunting them for food."

In an effort to build up a global database, Mr Norman is encouraging snorkellers and divers to send in photos of the harmless sharks to his online library.

"We're trying to get people to become research assistants, which helps create a sense of community involvement and an awareness of the need for conservation," he said.

The whale shark data library can be found at the website www.whaleshark.org