All of Sydney’s northern beaches have been closed and authorities have told people to stay out of the water. There have been four shark incidents in New South Wales in just three days following a period of intense rainfall over the weekend.
Two people are critical; one a 12-year-old boy injured in Sydney Harbour on Sunday 18th, and a surfer in Manly on Monday January 19th. An 11-year-old boy was extremely lucky when a shark took a chunk out of his surfboard on Monday afternoon and he escaped uninjured, but on Tuesday 20th another surfer was bitten near Port Macquarie, further north of Sydney.
It is believed that the murky waters along the coast, which extend into Sydney Harbour, are contributing to the issue after the torrential rains.
Sydney observations from the Bureau of Meteorology (BoM) reported 126.8mm (5”) of rain on Sunday 18th January, a phenomenal amount after a dry start to 2026. Nearby areas saw even more rain, as emergency services were inundated with calls as wild conditions and severe thunderstorms took hold. There were flash flood warnings with localised evacuation calls, power outages and closed roads. Changing conditions in the coastal waters and near to Sydney Harbour have resulted as the rain runoff from inland reaching the estuaries and coasts. There is poor visibility in the water for swimmers and surfers, but the murky conditions change animal behaviour too.
The overflow of freshwater (rich with nutrients from farms and waste treatment plants) attracts baitfish, larger fish and diving birds, which then draws bull sharks closer.
Bull sharks are a distinct species, not male sharks. Their numbers tend to peak in the Sydney region at this time of year before they move north to Queensland’s warmer waters. Bull sharks are present when water temperatures are at or above 20 degrees and are not put off by murky waters or low visibility. They will curiously bite something that they might bump into in the unclear waters. Surfers or swimmers, even splashing children, will attract attention and although sharks would usually attack human,s the murky conditions mean it is more likely that they could coincide.
NSW Premier Chris Minns
“We have incredible beaches and waterways in NSW, but sometimes we need to stay out of them for our own safety. Experts recommend waiting 72 hours after a storm to swim in the harbour (and rivers and estuaries) and be mindful of swimming or surfing at ocean beaches for 24 hours after a large downpour. It's the best way to avoid pollution washed in by the rain, and any sharks who might mistake you as a food source.”
The bull sharks can tolerate brackish (reduced salinity), even freshwater, rather than the salt water of the sea. After heavy rains, they will move closer to the coasts, into estuaries, looking for food but not able to see silhouettes of what is ahead. If they do bump into something or someone, they might give it a nibble to see what it has encountered in the unclear waters.
Open water swimmers are warned here in the UK against going into the sea after heavy rain due to pollution runoff. The Australian authorities are suggesting up to 72 hours after torrential rainfall, so that the waters settle and anything lurking has time to disappear. Many of the bull sharks are now tagged which allows their migration and movements to be monitored.
People thinking about entering the water are being told to be SharkSmart, a national campaign to hopefully stay safe in estuaries and along the coasts. "The NSW Government launched the Shark Management Strategy in an effort to minimise shark/human interactions - to help water users be as safe as possible and to learn more about the role and population of sharks in NSW waters". There is also increased monitoring by drones and first aid provision along the coasts this summer.
Thanks to Alison Murray for Australian beach photos
Loading recent activity...
