Peek at shark's private life

Scientists have gained a glimpse of the private life of one of nature's most feared creatures - the great white shark, writes Harriet Swain.

A 3 metre female was fitted with a computerised tag that recorded swimming depth and water temperature every four minutes and gave her position every 24 hours.

Her movements were logged from the moment she was caught and released off the Neptune Islands, southern Australia, in August, up to her accidental death at the hands of commercial fishermen in November.

By the time she was captured she had travelled close to the head of the Great Australian Bight, a distance of about 600km and farther than has been recorded for any other tagged white shark in Australian waters.

The tag and its data provided experts with the Commonwealth Scientific and Industrial Research Organisation Marine Research with 26,000 records of the shark during the two-month period. It is the first time an archival tag, originally developed to study the migration patterns of tuna, has been successfully recovered from a white shark.

"Most of the tagging data we have to date tells us only where a shark is tagged and where it is caught but tells us nothing of what the shark does in between," said John Stevens, a shark researcher with CSIRO and co-leader of the project.

"The depth track opens a window into the private life of the shark, which would otherwise be impossible to understand." It shows that the shark moved extensively between the surface and depth, some days spending long periods at the surface.

The project, funded by the Australian federal government's natural heritage trust and supported by state fisheries authorities, the commercial fishing industry and marine recreational groups, will help towards a national recovery plan for the white shark.