Do shark nets really protect us or are there better options?
Hitting the beach plays a huge role in the Aussie way of life.
But in some parts of the country, the danger of a shark attack is real.
Shark nets are the most common way to protect swimmers on busy beaches.
But are they really protecting us?
We looked at how shark management works.
What are shark nets and how do they work?
Shark nets are large mesh nets about 150 meters long and suspended about 6 meters into the ocean.
They are attached to floats and anchored to the seabed to ensure they stay in place.
The sharks get caught in the nets and if the contractors find out they’re on a target species list, they kill them.
Sharks can swim around the nets and are often only caught when they pass the nets a second time when returning to sea.
New South Wales uses nets on 51 beaches, removing them at the start of the whale migration season, from May to September, to protect the mammals.
queensland does not remove its shark nets for the whale migration.
It manages shark nets and drums on 86 beaches.
In Western Australiameasures that kill sharks are no longer used after thousands of people protested government shark culling programs in 2014.
WA authorities tag and track sharks, use drones, set up eco-barriers (a complete swim closure that keeps sharks out) and subsidize personal shark deterrent devices.
No other state or territory is trying to manage sharks.
Do shark nets help protect us from sharks?
Research suggests mosquito nets might help, but many scientists believe there are better alternatives.
Shark nets only cover part of a beach, so they don’t eliminate all risk of attack.
A 1997 research paper by shark scientist Sheldon Dudley found that shark netting programs on beaches in Queensland, New South Wales and South Africa were “impressive” in reducing the total number of shark attacks.
He found that attacks fell by about 90% on beaches after the introduction of programs that included mosquito nets.
But a report prepared by shark researcher Daryl McPhee in 2012 found that while the numbers suggested the nets were effective, there was more at stake.
“The fatality rate is highly unlikely to be the result of mesh activities, but is likely to be a function of improved beachfront response time and first aid procedures,” said his report for the Western Australian Department of Fisheries.
Why don’t people like them?
Simply put, shark nets kill sharks.
But they also kill many other sea creatures.
Australia is one of the only countries in the world to actively kill captured sharks in nets and on drums in an effort to protect people.
Australian Marine Conservation Society shark biologist Leonardo Guida says the Queensland government lists 19 target species that can be killed, including great whites, tiger sharks and gray reef sharks.
Sharks are not allowed to be killed on the Great Barrier Reef.
Queensland Department of Agriculture and Fisheries data shows its program caught 826 sharks last year using nets and drums.
But he also captured 21 dolphins, six humpback whales, 110 turtles and 90 “other” animals.
A report from the New South Wales Department of Primary Industries showed nets caught 40 target sharks there – white sharks, bull sharks and tiger sharks – during the 2021/2022 mesh season.
But they also captured 335 non-target animals, including turtles, rays, dolphins and fish.
This is lots of bycatch.
Contractors release non-target animals when found, but sometimes it’s too late.
Are SMART battery lines better than nets?
SMART drum lines are baited hooks that, when bitten, send a signal to authorities who will rush to tag and release the shark.
But running them is expensive because contractors have to be paid to be on call, waiting for a shark to bite.
In recent years, SMART battery line trials have been deployed on Australian beaches.
Dr Guida says they are a step in the right direction if used as a replacement for existing shark nets or traditional drum lines.
But he says the money could be better spent paying scientists to tag and track sharks without using the hooks.
Traditional drum lines, without the alarm technology, are still used in Queensland to catch sharks on the end of a baited hook suspended from a drum in the ocean.
Battery lines are checked regularly, but animals die if left there too long. All targeted sharks still alive when brought up are killed.
Surely there are better options?
Many alternatives are being considered in Australia to keep sharks off the beaches.
But testing is expensive and there is no single strategy that would work for different water conditions across the country.
There is also no quick fix.
A report from the Queensland Department of Agriculture and Fisheries in 2019 identified more than a dozen different systems that could be used.
They include CleverBuoys that send out sonar signals, human spotters, drones, anti-shark barriers and cables that emit low-frequency pulsed electronic signals to ward off sharks.
Dr Guida says using a combination of strategies could reduce the risk of attacks in Australia.
But he says education and awareness are fundamental.
How can I reduce my risk of being eaten?
The risk of being bitten by a shark is less than one in a million.
But if you still don’t like your odds, there are a few things to keep in mind to prevent yourself from being shark bait.
Seabirds diving in the ocean indicate a bait ball – where there is a bait ball, there will likely be sharks. Stay vigilant!
Another good tip for surfers and swimmers is to stay away from river mouths after heavy rains.
Nutrients flowing into the ocean can attract animals to feed, and reduced visibility after rain is ideal for ambush predators.
Anti-shark suits and repellent devices attached to boards and strips have also started to hit the market.
Studies have shown that the polymer fibers in shark proof suits reduce the size and depth of shark bites, and therefore reduce blood loss which can lead to death.
Several studies have proven that repellent devices reduce the risk of interaction with sharks.