Scientists from the West Australian Department of Fisheries are looking into the odds that the rising high temperature of the sea waters in the state are what caused sharks to swim near the shore and eventually attack humans.

Scientists led by Dr Rick Fletcher, the department's research director, said the record heatwave that occurred between 2010 and 2011 off the WA coast could have been the reason for the increased shark activity on the premise that the predator animal was forced to come near the shore in search of food due to declining fish stocks.

A marine heatwave, according to the organisation, occurs when areas of ocean water hit 30 degrees Celsius, which in turn forces fish stocks to disappear and relocate to cooler sea waters. Without food, predators like sharks will then go closer in to shore because fish collect in cooler waters.

"It may be the sharks are coming in with the colder water or it may be that the things they're feeding on are coming in with the colder water and the sharks are following them," Stuart Smith, Fisheries director general, was quoted by the West Australian newspaper.

"If there is a relatively smaller area of cooler water inshore, then the sharks could be concentrated in that smaller area," Mr Fletcher said.

"If we actually understand a little bit more about what conditions are more or less likely to have concentrations of White Sharks or Tiger Sharks, than we can inform the public about what the conditions are likely to be," he said.

"Two years past that initial heatwave, what's happened both to the stocks but also what's happened to the oceanographic conditions, have they returned? Or has that change dissipated over the past two years."

Between 2010 and 2011, five people have been killed in shark attacks at WA beaches.

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