South West Rocks was a hive of shark activity over the past week, with a tagged bull shark registered every day from May 8 to May 15.
Daniel Bucher, an associate professor of marine biology and fishery science at Southern Cross University in Lismore, said it was likely it was the same shark continually setting off the Department of Primary Industries receiver, which picks up signals from sharks that have been captured and tagged.
Reports of detected sharks are compiled on the Dorsal App, which shows the daily shark activity taking place in South West Rocks over May.
Although DPI Fisheries don’t provide information as to which individual shark has been pinged, Assoc Prof Bucher said it was “most likely” the same creature.
“In all probability, it's the same shark,” he said.
“There’s not that many bull sharks that are tagged compared to great white sharks."
The associate professor said bull sharks typically roam large areas and aren’t usually territorial, but would stay in the one place for a period of time if there was a plentiful food source.
“If it’s been raining and there's plenty of food coming out of the river, that’ll keep them around,” Assoc Prof Bucher said.
He said that at this time of year, bigger bull sharks had vacated river systems for the warmer temperatures of the ocean.
“We’d probably expect the bigger sharks to be out of the rivers by now,” he said.
“The smaller ones will spend their first few years up in the rivers, but by this time of year there’ll be fewer of the bigger ones in them.”
The Dorsal App crowd sources information about shark sightings, as well as receiving information from authorities such as the Department of Primary Industries.
According to the Dorsal App, a 2.92m female bull shark was caught, tagged and released at the South West Rocks breakwall on Monday, May 1.
The Dorsal App has recorded three sightings so far this month (as of May 15) at Crescent Head.
South West Rocks has one of 20 shark listening stations in the State, with nearby Port Macquarie and Crescent Head also having the shark detection equipment.
The listening stations were introduced in the 2015 Shark Management Program, which also included ongoing aerial surveillance of sections of the NSW coastline and shark barriers trialed at Ballina and Lennox Head.