Shark nets are not fit-for-purpose. They do not protect swimmers and kill hundreds of other marine animals, including threatened species. So why do we still deploy them in Australia, and what other technologies should we be using instead? Sarah Jacob asks the Australian Marine Conservation Society’s shark scientist, Leonardo Guida.
The statistics coming out of shark control programs are quite worrying from a conservation standpoint, with more than 60% of species caught in NSW being threatened species. How do the two main lethal techniques – shark nets and drumlines – compare, and what kinds of non-target animals are captured?
A drumline is a baited fishing hook. In Queensland the shark nets are about 186 metres wide and 4-6 metres in depth. So they don’t stretch to the length of the entire beach. Nets are essentially invisible in the water and will capture almost anything that hits it. There’s a greater degree of bycatch. What that means is that you’re not only catching sharks but you’re also catching turtles, dolphins, dugongs, and as we’ve seen in Queensland recently, whales as well. In NSW in particular, they are a [sting] ray killing machine. There are hundreds of rays that are caught every year, more so than other animal. Drumlines still catch turtles and dolphins that bite the bait, but generally the variety of animals is much less than for nets.
How do SMART drumlines work?
The Shark Management Alert in Real Time (SMART) drumline is a piece of technology that’s linked up to a satellite. If a shark or any other animal bites that hook it will pull a trigger, and that sends a signal to a satellite which is beamed back to Fisheries offices, then they head out to the drumline, and release the animal with a tag.
Why are tagging programs important?
The benefit of shark tagging programs is that we get this wealth of information that can tell us how sharks move, where they go, why they move. This translates into resources that not only help us manage our fisheries, and our interactions with sharks, but also to communicate to the public about certain conditions where the [likelihood of] presence of sharks might be higher than normal. Then people can make informed decisions about whether they want to go into the water at that time.
A 2017 study of public perceptions of shark nets at Sydney beaches found that there was strong support for shark nets but much less support for direct culling measures like hunting of sharks. It was suggested by the authors that the reason for this is that public education is lacking. How important is public education on this issue?
There seems to be this perception that shark nets are a barrier, and they’re not. There’s a perception that a shark net extends from surface to bottom, that it extends across the whole beach and no shark can get through. But sharks can swim around, under and over the net. One study that found that 40% of sharks caught in nets were actually on the shore side of the net.
Public education is fundamental for any strategy to improve bather safety. In NSW, as part of their Shark SMART strategy, they have huts on the beach where people can go and ask questions. Queensland does not [have a public education program]. The Australian Marine Conservation Society and Humane Society International are partners on a campaign called Shark Champions, which is an effort to educate people on how shark control works.
Why are shark nets still a major part of risk mitigation on Australian beaches, considering that they have been proven not to be effective in protecting swimmers?
Partly it’s because it’s entrenched in culture, and there’s a reluctance to change because [nets] have been around for so long with the perception that it “seems to work”. NSW is a bit more progressive, recently they announced greater investment in drones for use along the coast. Queensland is considerably further behind, they haven’t implemented any non-lethal technologies as yet. I think that there is perhaps a political disincentive to move towards [non-lethal] technologies, as no politician wants to be the one who takes out a drumline or a net and then someone gets bitten, because then that can be used politically against them.
Is there anything that swimmers can do to reduce their risk?
There is the Shark Shield device which has been shown to reduce the risk. In NSW the Shark SMART app gives you information on whether you should go into the water in the first place. There are environmental conditions that can help you judge the risk of going into the water. For example, at river mouths, particularly after a storm or heavy rainfall, you will see a spike in shark activity, especially bull sharks. That’s because conditions are favourable for them to hunt. Another thing is when you see a flock of seabirds congregated in one area, repeatedly diving into the water, that’s an indication of a high concentration of fish. If there are sharks nearby, it’s an easy feed for them, so they will probably be involved in the feeding as well.
The 2017 public perception survey found that most people interviewed considered that the media oversensationalised shark attacks. What can the media do better in this regard?
The media has an important role to play, given that it’s from the media that most people learn of shark bites – and you’ve probably noticed that I haven’t used the word “attack”. That’s a simple thing that the media can do, is to call them shark “bites”. The word “attack” is very inaccurate. The definition of that word is to consciously pursue someone with the intention of injuring or killing it. Sharks are very curious but they don’t have hands like we do, they have mouths full of razor blades – that’s all they have.
Photos: HSI/AMCS/N McLachlan