A Sydney couple was playing fetch with their dog at an off-leash beach in Sydney's south when it was taken by a 3.5-metre shark, in what experts say is a relatively rare occurrence.
The American Staffordshire Terrier, believed to be a rescue dog named Molly, was pulled under while swimming at Bonna Point in Kurnell around 3pm on Sunday afternoon.
The Sutherland Shire Council on Monday issued a warning to swimmers and pet owners to stay away from waters near the area after Molly's owners alerted them to the attack.
The couple were "pretty traumatised" by the horrific incident, Fairfax Media reports.
"We were just throwing the stick in the water. The tide was really far out and there was a bit of a drop off (where the water became deeper)," Molly's owner Nigel said.
"It was very quick. It just took her under the water."
A Department of Primary Industries spokesperson said there had been other shark sightings in the Botany Bay and Brighton Le Sands area in recent weeks.
James Cook University shark scientist Colin Simpfendorfer said experts didn't keep figures on sharks attacking dogs. But he added: "I wouldn't say it's common."
"It's certainly not something we hear about very often," Professor Simpfendorfer told AAP.
A council spokeswoman said lifeguards patrolled Kurnell beaches on Monday to warn people to keep out of the water.
Signs have also been installed to alert the public to the shark sighting.
"NSW Department of Primary Industries advises people to avoid swimming or surfing when it is dark or during twilight hours and encourages the use of the SharkSmart app which has safety tips for swimmers, surfers, divers, snorkellers and spearfishers," the council said in a statement.
