People have been warned to take extra care in the Coral Bay area.
"Adhere to beach closures advised by local government rangers, Parks and Wildlife Service officers or Surf Life Saving WA," the department said.
The most recent shark attack in Western Australia happened near Broome, also in the state's north, last month.
Brett Highlands, 48, was attacked off Quandong Beach by a suspected three-metre tiger shark.
He suffered bites to his forearm and hand.
"It was the chomping effect that I really felt," he told 7 News.
"Like a dog trying to get a grip of a bone. Just a wild animal attached to my arm."
In November last year, 59-year-old Charles Cernobori died after being attacked by a shark off Cable Beach at Broome.
Cernobori, a local hotel worker, was attacked about 9am when he was bodyboarding.
Emergency crews were called to the beach and CPR was carried out, but Cernobori died at the scene.
Mark Sanguinetti, 59, was surfing when he was killed by a 4.5m white shark at Tuncurry Beach, near Forster on the NSW mid-north coast, last month.
He saw the shark and tried to warn others before the animal turned on him, biting him on the upper right thigh.