Australia's iconic beaches are experiencing an unexpected side effect of climate change that might make you think twice about your summer swim - but probably shouldn't. New research has revealed that bull sharks are lingering around Sydney's popular beaches for an extra 15 days each summer compared to 15 years ago, thanks to warming ocean temperatures.

While this news might sound alarming at first glance, the reality is far more nuanced than the headlines suggest, particularly for the millions of Australians over 60 who rely on beach activities for their physical and mental wellbeing.

The Science Behind the Extended Season

Bull sharks, which typically migrate between Queensland and New South Wales following warm water temperatures, are now spending an average of 15 days longer off Sydney's coast during summer than they did in 2009[1][2]. Climate analysis shows that average water temperatures during October-May have been increasing over the past 40 years, with Sydney's coastal waters warming by 0.67°C since the 1980s during bull shark season[3][4].

Dr Nicolas Lubitz from James Cook University, who led the 15-year tracking study, explains: "Once regular winter migrants to Queensland, these apex predators are now making themselves at home off local beaches as waters aren't cooling below their preferred 19°C as fast as they used to"[5].

The implications extend beyond just timing. Early evidence suggests juvenile sharks are already appearing in rivers further south than was historically the case, potentially leading to new breeding grounds and challenging existing ecological boundaries along Australia's east coast[6].

Putting the Risk in Perspective

Before you swear off beach visits entirely, consider this: Australia recorded just 9 unprovoked shark incidents in 2024, with zero fatalities - well below the five-year annual average of 15 incidents[7][8]. Globally, 2024 was described as "an exceptionally calm year for shark bites," with only 47 unprovoked attacks worldwide, down 22 from the previous year[9].

Australian waters witness an average of 2.7 fatal shark attacks annually (2014-2023), and this slight increase correlates with our growing coastal population and the rising popularity of ocean activities rather than indicating a significant change in shark behaviour[10].

Shark attacks remain rare in ocean-loving Australia, with most serious bites coming from three species: bull sharks, great whites, and tiger sharks. Not all shark attacks are fatal, with many incidents resulting in minor injuries, and some encounters resulting in no injuries at all[11][12].

Beach Safety Technology is Evolving

The good news is that beach safety measures are advancing faster than climate change can alter shark behaviour. NSW now operates 50 drone surveillance locations across the state, with every coastal council area having at least one drone patrol location during 2025/26, alongside 305 SMART drumlines and 37 tagged shark listening stations[13][14].

SMART (Shark-Management-Alert-In-Real Time) drumlines have proven to be the most effective tool for catching target sharks while minimising the catch of non-target animals and maximising the survival of all animals caught on the gear, with over 300 currently deployed daily from Tweed Heads to Pambula[15].

Perhaps most impressively, tagged sharks trigger alerts when they swim within range of listening stations, providing real-time warnings to beachgoers through mobile apps like SharkSmart[16][17][18]. Sharks that are tagged and relocated move away from the coast for an average of 74 days and travel an average of 165km away, providing confidence that SMART drumlines effectively remove immediate risk for several months[19].

The Changing Shark Net Landscape

Traditional shark netting is facing increased scrutiny and gradual phase-out. NSW is removing shark nets one month earlier in 2025 (on 31 March instead of 30 April) to respond to increased turtle activity, while increasing inspection frequency during February and March[20][21].

Between May 2023 and July 2024, listening stations picked up 497 individual target sharks - a staggering 33 times the amount caught by shark nets[22][23]. The NSW government has reportedly asked Waverley, Northern Beaches and Central Coast councils to each select a beach to trial the removal of shark nets this summer[24].

Why Beaches Remain Vital for Senior Health

Despite the extended shark season, beaches continue to offer irreplaceable health benefits for older Australians. Australian research on 1,700 men aged 70 and older found that those who swam were 33% less likely to fall compared to men who didn't swim.

Swimming and beach activities provide unique advantages for seniors that can't be replicated elsewhere. Around 90% of body weight is supported by water during swimming, making it essentially weightless exercise that won't put unnecessary strain on joints. A 2016 study found swimming helps relieve pain and improve quality of life among people with knee osteoarthritis and fibromyalgia.

The mental health benefits are equally important. Group exercise contributes to balanced health among older adults, providing community and social connectedness that can help reduce feelings of social isolation and depression. Swimming releases endorphins that help relieve stress and improve mood, with aquatic exercise showing promise as a treatment for managing depression.

Smart Beach Safety for Seniors

The key is not avoiding beaches but being smarter about when and how you use them. One of the simplest safety routines is to only swim at patrolled beaches and stay between the flags, where lifesavers and lifeguards monitor conditions and maximise safety for all beachgoers[25].

In NSW, white sharks are more commonly seen between May and November, bull sharks from October to May, and tiger sharks year-round. White sharks are more likely to be present within a kilometre of coast around 11am, while bull sharks are most active from midday through the night[26].

Avoiding dawn, dusk, and night swimming significantly reduces risk, as these are typically feeding times for sharks[27][28]. Beach safety experts recommend swimming with a buddy and avoiding swimming alone[29].

The Bigger Climate Picture

The extended shark season is just one symptom of much larger changes occurring in Australian waters. Waters around Australia are projected to warm by 1-2°C by the 2030s and 2-3°C by the 2070s, with the greatest warming off south-east Australia due to strengthening of the East Australian Current[30][31].

The increasing frequency of marine heatwaves has contributed to permanent impacts on marine ecosystem health, including depleting kelp forests and seagrasses, poleward shifts in marine species, and increased occurrence of disease[32][33].

Interestingly, there's evidence that great white shark summer habitats are decreasing in northern NSW and Queensland as they prefer colder waters, suggesting a complex reshuffling of marine predator distributions rather than simply more sharks everywhere.

Technology and Apps to Keep You Informed

Modern beach safety increasingly relies on smartphone technology that's particularly valuable for regular beach users. The SharkSmart WA app combines shark activity information with beach safety features, weather forecasts, and provides near real-time information on shark activity including current alerts and warnings[36][37].

Over the 2023-24 season, 400 drone pilots for Surf Life Saving NSW flew more than 36,000 flights across nearly 10,000 hours, observing 362 sharks during their patrols[38].

Western Australia has even pioneered financial incentives for personal protection: The WA government offers a $200 rebate to residents who purchase scientifically-proven personal shark deterrent devices, with the program proving so popular that funding has been extended beyond the original 1,000 devices[39].

Looking to the Future

Continued climate change could transform seasonal shark patterns, potentially leading to year-round bull shark presence in southern NSW in the future, with more tropical species becoming year-round residents in the Sydney area[40][41].

However, this doesn't spell doom for Australia's beach culture. Leading researcher Dr McPhee gave evidence suggesting it was "highly plausible" that removing lethal technologies like shark nets tomorrow would show no discernible change in unprovoked shark bites, including fatalities, with some reports showing more shark interactions at beaches with nets in Sydney's metro region[23].

A Balanced Approach to Beach Enjoyment

Climate change is indeed altering the timing and patterns of marine life around Australian beaches, including extending the bull shark season by a meaningful two weeks. But context matters enormously: we're talking about extending a season for encounters that remain extraordinarily rare, in an environment that's becoming safer through better technology and understanding.

For Australian seniors, the health benefits of beach activities - from the 33% reduction in fall risk associated with swimming to the crucial social connections formed through beach communities - far outweigh the marginally increased presence of bull sharks during what were already the months of highest activity.

The message isn't to avoid our beloved beaches, but to embrace them more intelligently. Download the SharkSmart app, swim at patrolled beaches between the flags, choose your timing wisely, and stay informed about conditions. The ocean that has shaped Australian culture for generations isn't becoming off-limits - it's simply asking us to be a bit more aware of the neighbours we're sharing it with.

Your regular beach walk, swim, or surf session remains one of the best things you can do for your physical and mental health. Just make sure you're doing it with the wisdom and awareness that comes with understanding our changing marine environment.