Moreton Bay charter boat deckhand Bryce Daly is starting to feel unsafe swimming the waters he’s grown up fishing.

“You’ve always got a shark in the back of your mind,” the 32-year-old Jimboomba man says.

Two shark encounters last month captured national attention and rocked coastal communities along the densely populated south-east Queensland coast. In early February, 17-year-old Charlize Zmuda died was killed while swimming at a Bribie Island beach. Three weeks later, a 29-year-old man was bitten at a popular snorkelling spot further out towards sea off Moreton Island. He survived after being airlifted to hospital.

On 7 March, a swimmer in her 50s was bitten by a suspected bull shark at Gunyah beach near Bundeena in Sydney’s south. And last week, with south-east Queensland and northern New South Wales still reeling from the wild weather generated by ex-Tropical Cyclone Alfred – which has gouged out beloved beaches – came the news that a surfer on the other side of the country was killed by a shark, at remote Wharton beach in Western Australia.

With such such tragedies making headlines, the sense of unease felt by ocean-goers such as Daly is understandable. But is widespread fear of sharks justified?

The University of Florida compiles data on the world’s unprovoked shark bites – which excludes bites sustained while people spearfish or release sharks from hooks or nets – in its International Shark Attack File.

It says Australia typically averages the second-highest annual number of reported bites and fatalities, behind the United States. But 2024, its researchers say, was an “exceptionally calm year for shark bites”, both here and abroad.

Of 47 unprovoked attacks, only nine were in Australia – and none of them fatal. Four fatal attacks were recorded around the world. In contrast, 300,000 people drown around the world every year.

The year prior, 2023, however, four of 10 fatal attacks were in Australian waters. And experts say that in Australia and around the world, shark bites on humans have increased steadily over the past few decades.

But, they add, so too have human populations and the number of people taking up water sports such as surfing.

James Cook University shark expert Dr Andrew Chin says a more useful metric than bites a year would be the number of bites per people entering the water.

“That’s the real statistic,” he says. “But we don’t count how many people are entering the water … we just don’t have that data.

“So the only thing we can say is that the risk is extremely low and it is very difficult to pick out any signal from the data, given how rare these events are.”

But it is not just traumatic and high-profile attacks that have Daly on edge. For years, he says, more sharks have been biting catch off fishers’ lines.

“I took a mob of people out on a charter boat the other day and everyone hooked up to a snapper,” Daly says. “Only one was landed.

“We all feel it, you know, as fishermen. It’s a massive issue.”

So Daly has decided to take matters into his own hands – he wants to organise a shark fishing competition in the bay. If he does, it won’t be the first.

Last May, the Moreton Bay Game Fish Club competition “fish of the month” was shark.

“With sharks in plague proportions everywhere you turn, it shouldn’t be too hard for those wanting to get on the board for this FotM comp,” organisers wrote.

And Daly believes the sharks that dog his catch have not only become more numerous – but cannier.

“They’re smart now,” he says. “They know to follow boats. They know if you’re fishing, that you’re dropping lines.”

Smart sharks may sound like the plot of a B-grade movie but, as it turns out, Daly is on to something. Scientists and authorities call the behaviour Daly describes as shark depredation – and most agree it appears to be on the rise.

A Queensland Department of Primary Industries spokesperson said shark depredation was “a key issue”, not only in that state’s fisheries, but across the country.

The nationwide, industry-backed Fisheries Research and Development Corporation was funding the DPI to run a two-year project to work out ways to mitigate depredation and would be holding workshops with fishers, the spokesperson said.

Griffith University shark management expert Dr Vincent Raoult agrees depredation is a “well-recognised issue”. But that doesn’t mean there are more sharks nor that the ocean has become any less safe for swimmers, Raoult says.

“There’s definitely an acknowledgement from the experts – and by experts, I mean the scientists in this case – that there’s more and more sharks being spotted, particularly bull sharks, by recreational and commercial fishers,” he says.

“Now, that is very different to whether shark populations are increasing or not.”

Raoult says there simply is no data to back up anecdotal reports of increasing shark numbers. The only hard evidence for changes in shark population comes from the state’s lethal shark control program in Queensland.

Over the last two years there have been more sharks caught in Queensland. But year on year catch rates always fluctuate, Raoult says.

“So what you have to look at to understand populations is long-term trends over decades, really,” he says.

“And there’s not really any evidence yet to suggest that there’s been a recent explosion in numbers of sharks.”

Instead, Raoult offers a number of alternative explanations for the growing concerns of encounters between anglers and the ocean’s apex predators. Australia’s population continues to grow, he says. More of those people, especially since the pandemic began, are game fishing. Prime fishing spots are attractive to both anglers and sharks. And, like Daly, Raoult says sharks are “intelligent predators”. This increased exposure might be teaching sharks to associate fishing boats with food.

Add to that, the scientist says, most fishers now carry phones capable of capturing and sharing their shark encounters.

“So we’re reporting and seeing those shark interactions more often than we have ever had before,” Raoult says. “But what fishers see is not necessarily representative of what happens if you just go for a swim on the beach.”

One expert who is trying to provide evidence that could either back up or sink the claims of anglers such as Daly is the University of the Sunshine Coast’s Dr Bonnie Holmes, who is midway through a three-year research project to tag and track bull sharks in the waters north of Brisbane.

Holmes says her team is “probably a couple of years away” from obtaining “hard data to support these anecdotal assumptions” about bull shark numbers. But she does describe many of the waterways she targets with drum and set lines baited with freshwater eel as “pretty healthy ecosystems” – by which she means home to plenty of sharks.

Unlike most shark species, bull sharks can survive in both fresh and saltwater and thrive in rivers and estuaries. In fact, researchers believe that if south east Queensland’s bull shark population is growing, it may partly be due to the canals built for housing along the coast that are prime bull shark habitat.

“For us fishing on the water, it’s very easy to catch bull shark in most places,” she says.

Already her team has tagged about 100 across three systems: the Noosa and Maroochy river systems and the Pumicestone Passage.

Those “sheer numbers” are probably one of the other most interesting things her team has found so far, Holmes says.

“But, the thing is, these animals are there and have been there for quite some time, and we have a lot of people that use our lower estuaries swimming, paddleboarding, kayaking, fishing,” she says.

“So we’re already, for the most part, comfortably sharing the waterways with these animals and probably have been for a really long time.

“There’s no reason that we can’t continue to do that.”

And anglers like Daly could yet prove crucial in finding ways to do just that. The deckhand says he would like to feed data from his proposed shark fishing competition directly to scientists.

“We could catch and tag sharks,” he says. “So that, actually, they can record all them numbers and see exactly where them sharks are going and what they’re doing.

“If we could give them that sort of data and knowledge about it that would be awesome – because, until that happens, you know, hands are tied.”