Australian scientists are collecting DNA samples from whale sharks at Ningaloo Reef in Western Australia to unlock the mystery of where they travel to and how deep they go.

The CSIRO researchers will also use satellite tags to try to build a picture of the life of the largest fish in the sea whose behaviour is still unknown.

“Taking genetic samples from whale sharks will provide a critical piece of data on their age to help us estimate the population on the western coast of Australia and the eastern Indian Ocean,” says CSIRO Senior Scientist Dr Richard Pillans.

“We will also be using satellite tags to track where the whale sharks go to gain insight into their behaviour.”

Previous tagging has revealed whale sharks travelling south to Perth and others have been located as far as the Gulf of Carpentaria, 3,500 km away. Some whale sharks have been clocked diving as deep as 1.8 kilometres.

The whale shark work is part of a five-year, $5.4 million research partnership with BHP which includes turtle tagging, coral reef surveys in deep and shallow water and marine debris assessment.

“There’s still a lot to learn about whale sharks and the potential impacts of a changing marine environment but with more research we hope to find out more, including where whale sharks mate and where they go to give birth to their live young,” says Dr Pillans.

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