Did you know that shark mitigation technologies are being trialled along Randwick’s coastline? These technologies – SMART drumlines and shark listening stations – were rolled out in February this year, along with drones flying over NSW beaches, including Maroubra Beach.
Following Randwick Council’s decision in April 2021 approving the deployment of shark mitigation technologies in cooperation with the NSW Department of Primary Industries (DPI), SMART (Shark Management Alert in Real-Time) drumlines and listening stations were deployed along Randwick coastlines in February 2022.
These tools were put in place in at least 21 locations, 500 metres off the coastline to catch, tag, release and monitor dangerous sharks, and will complement the two shark nets already positioned in Maroubra and Coogee.
What exactly are SMART drumlines and listening stations?
A SMART drumline is a baited hook attached to two buoys and equipped with a GPS that can send alerts to contractors when an animal takes the bait. The contract boats then go to the site to tag the shark with an acoustic tag before taking it about one kilometre offshore and finally releasing the animal.
SMART drumlines are shown to be 15 times more efficient than nets in catching target sharks and are less likely to catch non-target animals. As a result, animals caught by these tools have 99 per cent of survival as compared to 40 per cent in nets.
Listening stations, on the other hand, are buoys that are capable of sending real-time alerts to the SharkSmart app, website and Twitter account whenever a tagged shark is detected to be within 500 metres. It provides the date and time, the location where it was previously detected and where it was tagged.
See the Shark Smart map here.
“They don’t often stick to one beach and ‘lurk’,” said Dr Paul Butcher, Principal Research Scientist with the DPI who has been tracking sharks since 2015.
“They move quite vast distances. We’ve seen one white shark travel to WA and back three times. It’s covered more than 40,000kms since it was first tagged in 2016.
“The benefit of this program is that we primarily catch the species that are responsible for most serious shark bites in NSW.”
Non-lethal alternatives
Along with these technologies, drones are also being used on 50 NSW beaches including Maroubra Beach. Dr Butcher is currently working on a program that would make autonomous, image recognition software-equipped drones that could fly over beaches and detect shark presence close to the beach and alert lifeguards who would usher beachgoers to safety.
Another research project aims to eliminate the need to capture sharks altogether. The project involves some environmental DNA sampling of water columns to “detect spikes or troughs that would indicate the presence or absence of white, tiger and bull sharks.” Dr Butcher said that a one-litre sample of water is enough to determine the presence of dangerous sharks in the region.
According to International Shark Attack File data, Australia ranks second in the world when it comes to the number of unprovoked shark bites in 2021. There have been just 12 unprovoked incidents recorded in 2021 which is lower than the region’s recent five-year annual average of 16 and significantly lower than the top ranked USA’s 47 incidents.
New South Wales recorded six incidents – two were fatal – whilst Western Australia had four and one of which was fatal. Queensland and Victoria have one incident each.