Rarely seen shark ritual spotted by news crew off WA coast

The 17 sharks, some up to 4m long, were filmed from a Channel Nine helicopter this morning and the vision will be aired on Nine News at 6pm tonight.

Shark expert Mr Hugh Edwards said the ritual had only been filmed twice before, once off Mexico and once near the Rowley Shoals off WA’s North-West coast.

“It’s exciting, it’s mind-blowing, this is some of the best shark vision I have seen.  It is a very, very unusual spectacle,” Mr Edwards said.

Hammerhead sharks are usually solitary animals and not seen in big groups.

"They were swimming in circles which we assume is a mating ritual. They certainly weren't hunting anything," Mr Edwards said.

"It's very unusual to see hammerhead sharks in a group and when they are it is regarded as a world-wide phenomenon.

"There are very few places in the world where it happens and nobody has ever heard of it happening off Perth before."

The mating behaviour of the hammerhead shark can be violent and recently scientists discovered the sharks can reproduce asexually as well.

Hammerheads are mostly found in tropical waters and there has never been a recorded attack on a human by this species of shark.

The news team was flying over the coast looking for a 4m shark which was reported to be just 50m from Sorrento beach this morning.