Shark Nets: Balancing Safety and Conservation

How much do you really know about shark nets? Editorial Assistant Imogen Grebert takes us through the pros and cons of this invention.

Australia—a land of golden shores that meet city, rainforest and desert. Known for its remarkable beaches and people who just can’t seem to get enough of them. Fun fact: if you were to go to one new Australian beach every day, it would take you 32 years. However, despite all these things being said, beaches in Australia often encounter a problem. No, it is not the bluebottles, jellyfish or even crocodiles that get everyone's hearts racing, but rather the sharks—the creatures of people's nightmares, lurking in the depths of the ocean, waiting to take a bite out of unsuspecting beachgoers. This narrative is further reinforced by media influences such as Jaws and The Shallows.

The fear that people harbour towards sharks and our average of twenty shark attacks in Australia per year pushed the government to implement shark nets on our most populated and local beaches, including Bondi, Bronte, Newcastle, Central Coast beaches, and across the NSW coastline.

Shark nets were first implemented in Australia around 1937, and were considered a way to cull sharks to safeguard swimmers. Since then, our understanding of the importance of sharks for ocean environments has changed, with shark nets now only being used from 1 September to 31 March (known as Mesh season) and being taken out for the winter. Though in the last 10 years, we have seen discussions on whether we should be using them at all or finding alternative measures instead. 

What are shark nets?

Shark nets are nets made out of mesh that sit about 500 metres away from shore. They are between four to six metres in depth and span about 150 metres in length, with a mesh size of 60 centimetres. The nets do not go all the way to the bottom of the seabed to avoid disrupting any ecosystems that might be there. They also use buoys and kegs to alert boats and other water transportation to be there. 

What do Shark nets do? 

Shark nets are a passive method of minimising the risk of sharks; they are not a deterrent. Their purpose is to reduce the likelihood of human-shark interaction, but they do not prevent it. Instead, they are a safety measure that the NSW Government has put in place. Sharknets are not enclosed areas or barriers, but a form of interception. What happens is that when a shark swims too close to the nets, they will be caught or entangled in them, stopping the potential threat to swimmers and surfers—though these nets can also catch other marine life. Some nets that are put in the water do have dolphin pingers and whale alarms to try to deter these marine creatures away but it isn’t always successful in doing so. Ultimately, shark nets provide intervention for shark-related accidents but aren’t guaranteed to stop them. 

How do Shark nets impact our environment? 

Over the last 10 years, the NSW government has conducted an annual report on how effective shark nets are in stopping shark attacks. Though there has been a decrease in the attacks, the nets aren’t always productive in preserving the marine life around them. In the latest report of 2023-2024, it stated that during the Mesh season, there were 15 target sharks caught and 240 non-target animals caught, with 92 animals (36 per cent) being released alive. Animals that were caught included multiple species of dolphins, turtles, stingrays, finfish, non-target sharks, and a whale. Each animal has a role to play in preserving the marine ecosystem, so even these casualties can have an effect on our oceans. The environment itself, however, is still preserved because of where shark nets are situated in the water. They do not touch the seabed of the ocean, meaning that they can’t harm coral reefs, seagrass beds or kelp forests. 

What are alternative measures to put in place?

As technological advances have occurred, so have alternative methods to shark nets, which several beaches on the NSW coast have begun to implement in tandem with shark nets. These include drone surveillance, shark tagging and listening stations, the Shark SMART app and SMART drumlines. 

Drone Surveillance 

Drones are aerial vehicles fitted with cameras that can monitor beaches in case of sharks coming in too close. The drones are manned by Surf Life Saving patrollers and allow them to determine whether the beach needs to be evacuated or not. They are used during normal patrol hours and are flown twice an hour for up to 15 minutes. Drones have been effective in the detection of sharks to prevent human-shark interaction. 

Shark tagging and listening stations, and the Shark SMART app 

Shark tagging is the process of attaching a tracking device and a microchip to either the dorsal or pectoral fin of a shark. The trackers can detect their movements and patterns, and when sharks pass within 500 metres of the employed receivers, they send out notifications of shark activity to beach authorities to let them know. This notification can then be sent to the Shark SMART app, which lets people know if sharks are in proximity to their nearby beach. One issue that this method faces is that it only works for sharks that have been tagged; sharks that aren’t tagged and swim by, no one would know. So if sharks are caught alive in shark nets, they are always tagged. This is incredibly important for shark conservation and allows scientists to be able to study sharks better. 

SMART Drumlines 

SMART stands for Shark-Management-Alert-In-Real-Time, and is a newer alternative that is starting to be used. The drumlines consist of an anchor, two buoys and a satellite-linked GPS communication device attached to a baited hook with sea mullet. When a shark bites and puts pressure on the bait and line, a magnet is released, alerting scientists and the boat crew to the animal. The team goes out to either tag and release the shark or release other marine animals. The drumlines are set every morning, 500 metres away from shore and collected at the end of each day.  

The issues surrounding shark nets and how to handle human-shark interaction are not black and white, but are grey. There is no one perfect way to manage this situation; rather inform ourselves on the importance of sharks and new technology that preserves both human and shark life – working together to build a dependable future. 

References 

5 effective alternatives to shark nets, Aug. 2023, https://www.seashepherd.org.au/latest-news/5-effective-alternatives-to-shark-nets/. 

SharkSmart. Shark Net trial FAQs. NSW Department of Primary Industries, Nov. 2016, https://www.sharksmart.nsw.gov.au/shark-nets/north-coast-net-trial/publications/faq.

SharkSmart. SMART Drumlines. NSW Department of Primary Industries, Nov. 2018, https://www.sharksmart.nsw.gov.au/technology-trials-and-research/smart-drumlines.

Shark Meshing (Bather Protection) Program 2023/24 Annual Performance Report. Department of Primary Industries and Regional Development, NSW Government, 2024, https://www.sharksmart.nsw.gov.au/__data/assets/pdf_file/0010/1570987/Shark-Meshing-Bather-Protection-Program-2023-24-Annual-Performance-Report.pdf.