The department of primary industries (DPI) is installing two ‘listening stations’ for tagged sharks in the ocean off Byron Bay’s Clarkes Beach and Ballina’s Sharpes Beach.
The beaches were chosen because they have both been associated with shark attacks in recent times.
The satellite-based system will track tagged sharks via a smartphone app called SharkSmart.
The app will provide a warning to users when tagged sharks approach the buoy carrying the receiver /transmitter.
A downside of the system is that it will only respond to tagged sharks and, despite a significant effort from DPI in the region, just 14 sharks have been tagged so far this year.
But a significant side benefit of the app is that it will also potentially minimise the number of protected sharks, such as grey nurse, accidentally caught on fishhooks.
A DPI map of the sharks tagged in north cost waters shows their significant movement, with some found as far afield as the west coast of Victoria and the south coast of Tasmania.
A DPI spokesperson said the north coast had been included in the program because of the two fatal attacks and other incidents in the region in the past 12 months.
They are being deployed in conjunction with so-called ‘smart’ drum lines, which will alert DPI when sharks are caught on them.
The animals are then tagged and released.
Wildlife groups have opposed the use of the drum lines, saying they will lead to unnecessary trauma and even death of the animals.
No Shark Cull chairperson Sharnie Connell said the survival rates of protected white sharks on the drum lines was ‘unknown’.
‘The stress the animals endure whilst they are attached to the hook awaiting the contractor to travel out to tag and release the animal is often lethal,’ she said.
‘There is also likely to be impacts on critically endangered grey nurse shark populations on smart drum lines,’ Ms Connell added
The group was particularly concerned that critical habitat for grey nurse sharks occurs in known aggregation sites at Byron Bay.
Once again you muddy the scientific waters by bringing the Grey Nurse into this story. It has been reported that these drumlines, if they are used, will be deployed during the day and retrieved at night. Because the Grey Nurse is essentially a nocturnal shark it is highly unlikely it would have any interaction with drumlines.