US tracked the travelling path of a great white shark

US researchers have made a remarkable discovery about the behaviour of great white sharks that could hold valuable lessons for how humans deal with them.They've tracked a female shark from Australia to South Africa and back again, changing some previous conceptions of how far and how fast the creatures can travel.The research is to be published in tomorrow's edition of Science magazine.

Karen Percy reports.

KAREN PERCY: "Have tracking device, will travel". That might well be the mantra for Nicole the great white shark, who's managed to impress scientists the world over with her long distance journeying.From Australia to South Africa and back again, Nicole undertook a trip of more than 20,000 kilometres, over a period of nine months.

RAMON BONFIL: This is the first ever recorded transoceanic movement of a great white shark anywhere in the world.

KAREN PERCY: Ramon Bonfil is from the Wildlife Conservation Society, based at the Bronx Zoo in New York City.The Mexican-born researcher has been studying sharks for two decades. He's led this research and is excited about these latest findings.RAMON BONFIL: For years we believed that white sharks were mostly coastal. A few years ago - maybe five, four years ago - some scientists in California discovered that they could move between California and Hawaii. But this is the first totally transoceanic, from one side of the ocean to the other, from coast to coast and then back.

KAREN PERCY: How do you know that this is indicative of all sharks' behaviour though? Because as I understand it, Nicole was only one of a number of sharks you've been tracking.RAMON BONFIL: Yeah, definitely. We, we don't know at this stage how common this behaviour is. This is the only shark that we were able to record going from South Africa to Australia. But we suspect, based on the numbers of sharks that we tried - which was only 32 in this study - one out of 32 crossed the Indian Ocean, that indicates to us that this is fairly common, or relatively common behaviour.

KAREN PERCY: The study will assist Australian researchers as well. Barry Bruce is with the CSIRO in Hobart.

BARRY BRUCE: We've started to unravel other areas of their lives, and that at least some of them spend some time out in the open ocean, sometimes crossing ocean basins. Now we have no idea why they do this and we have no idea how they do it, because they don't do it in a random way. They seem to know where they're going, and they certainly know how to go back to where they came from.

KAREN PERCY: Her extraordinary travels aren't Nicole's only down under connection, she's named after a certain Australian movie star.And her behaviour has particular relevance in Australia, where shark attacks are common.US-based researcher, Ramon Bonfil, says the study dispels the belief by some that great white sharks thought to be responsible for attacks on humans can be tracked, hunted and removed.

RAMON BONFIL: It is impossible because these sharks are so mobile and they can be here one day and they can be hundreds of kilometres tomorrow, and in a couple of months they could be across the entire ocean in a different country.KAREN PERCY: And the CSIRO's Barry Bruce, agrees.

BARRY BRUCE: The fact is that that shark might visit there, and it might go there the same time each year, but at other times it's thousands of kilometres away, and it's the same after a shark attack. Sharks generally leave the area after an attack, and if you catch one, it's probably not the same one, it's another one.

KAREN PERCY: The study is expected to go some way to devising a plan to manage the interaction between sharks and humans.