Shark-smart behaviour is one of the keys to sustainable fishing on the Great Barrier Reef with new research revealing the hidden financial cost of shark depredation.

Shark depredation - where sharks take hooked fish before they can be safely retrieved - is driven by the shark’s natural instincts.

But new research from the Queensland Department of Primary Industries shows that simple changes in fishing practices can significantly reduce interactions and help fishers keep more of their catch.

Senior DPI fisheries biologist, Dr Jonathan Mitchell, led the research and said the findings show the growing scale of the problem with an estimated 37 per cent of Spanish mackerel catch lost to sharks.

“We know now that depredation is translating directly into higher costs for fishers, from lost gear to increased fuel use,” Mitchell said.

“Moreover, depredation can also result in higher fish mortality and injuries to sharks, which at scale can have impacts on maintaining sustainable fish stocks across the Reef.

“Through our findings we know that there are steps that fishers can take to help mitigate the problem, and that is an area where we will continue to focus our research efforts.”

• These include:
• Turn your engine and echosounder off when you arrive at your fishing spot – this reduces noise and the chance of attracting sharks
• Fish in shallower depths
• Avoid cleaning your fish and dumping the waste where you are fishing
• Use handlines and/or electric reels – this may help you get your fish in the boat faster
• Consider using a shark deterrent device.

Chris Cochrane, the Reef Authority’s Director of Field Management Operations, said the findings reinforce the importance of the Reef Authority’s new Fish for the Future campaign.

“The Reef is home to around 135 species of shark,” Mr Cochrane said.

“When you’re fishing on the Reef, you’re in the shark’s backyard, so it makes sense to adjust what we’re doing to minimise any unwanted interactions. There’s no simple fix, but a few simple, shark-smart habits, and adapting how we fish, can go a long way in helping fishers avoid sharks and hold on to their catch.

“We want everyone to enjoy their time on the water and play their part to protect the Reef.”

Make sure you:

• Know where you can and can’t fish 
• Anchor in sand to avoid damaging coral
• Take only what you need for a feed, not to fill the esky

Click here for more information on how you can Fish for the Future.

For interviews, stills and vision, click here.

ENDS … 
Contact: Great Barrier Reef Marine Park Authority
Media Hotline: (07) 4750 0846 | media@gbrmpa.gov.au 

• Research by Queensland Department of Primary Industries (DPI) showed:
• Recent research on shark depredation in the Queensland Spanish mackerel fishery reported that 37% of catch is lost to shark depredation, on average, during recreational fishing trips, with 6% lost during commercial fishing trips (Mitchell et al. in review, Sumpter et al. 2025)
• Ten workshops were conducted with fishers across northern Australia to understand the impacts of depredation on fishing, what is causing it and which mitigation methods fishers are using to reduce it
• A national online survey was also conducted to collect information more broadly from fishers on their experiences with shark depredation and mitigation methods
• 2,599 fishers completed the online survey, including 1,473 fishers from Queensland
• Data from the survey indicated that shark depredation resulted in an average cost of $150 per trip in lost fishing gear and $100 extra fuel cost for recreational fishers

• Tips to reduce shark depredation:
• Move your fishing spot regularly - move on once you have caught a few fish and don't go back to the same fishing spot too often (sharks can learn that it's an easy source of food), If you start losing fish to sharks, move to another spot a good distance away.
• Fish in shallower depths and with lines close to the boat when trolling - fish can be retrieved quickly and sharks have less time to take them.
• Use handlines and/or electric reels - this may help you to get fish in the boat faster.
• Avoid using bait and burley (this attracts sharks), switch to using lures and jigs.
• Avoid cleaning your fish and dumping the waste where you are fishing (this attracts sharks), always discard fish waste far away from fishing and swimming areas.
• Switch the fish you target - if you find sharks are taking a particular species, try switching your target species.
• Turn your engine and echosounder off when you arrive at your fishing spot - this reduces noise and the chance of attracting sharks.
• The Qld Fishing 2.0 app is a simple, modern way for fishers to record and submit their catch information at anytime from anywhere.