A Sydney vet credited with saving a young woman's life after a shark attack says coincidence, training and the assistance of neighbours helped prevent a fatal outcome.
Public servant Lauren O'Neill, 29, was badly wounded after being bitten on the leg while swimming near a jetty at Elizabeth Bay, in the city's eastern suburbs, at dusk on Monday.
Ms O'Neill was saved by multiple neighbours, including vet Fiona Crago, who rushed to her aid after hearing her calls for help.
"I just focused on what I had to do which was to stem the blood flow and bandage the leg as best I could with what I had," Ms Crago told Ten News.
"My neighbours were amazing, everyone just kept talking to her and reassuring her until the paramedics arrived."
By coincidence, Ms Crago's wife had purchased compression bandages earlier on Monday which she used to make a tourniquet.
"(Ms O'Neill) was so brave, she was so polite, she was saying 'thank you' to people," Ms Crago said.
"I'm in no way heroic, I just did my job and what I'm trained to do and everyone else rendered whatever assistance they could."
But neighbour Michael Porter, who also rushed to help, said it would have been a different outcome had Ms Crago not been there.
"Fiona is a hero and I believe she saved her life," he told Nine's Today Show.
"I'm not sure what would have happened (without her) but it wouldn't have been good."
Ms O'Neill was rushed to nearby St Vincent's Hospital for surgery and was in a stable condition in the intensive care ward on Tuesday afternoon.
The vet was also lauded by Deputy Premier Prue Car as a "legend".
Sydney University shark policy expert Christopher Pepin-Neff said humans were an unfamiliar sight for the predators and could provoke the animals' fight-or-flight response.
"Sharks do not know what humans are, we are a very large land animal swimming through the ocean," he said.
The main method of sharks engaging with their environment is using their teeth, which can lead them to bite unfamiliar creatures.
"Bull sharks are biters, if you get in the way of a bull shark and it doesn't know what you are, it is going to bite," Dr Pepin-Neff said.
The beach-focused SharkSmart alert system has detected and tagged eight bull sharks off Sydney's beaches in the past week.
"Our research has highlighted that individual bull sharks are constantly moving throughout the harbour and there is no evidence of any territorial behaviour by individuals," Agriculture Minister Tara Moriarty said.
"Research has also shown that bull sharks are especially numerous when water temperature is around 22C, which is close to the average water temperature across Sydney at the moment."
The sharks make the journey to Sydney from Queensland every summer to hunt for fish.
People should be extra wary of sharks when in murky, dirty water, such as after high rainfall or floods, where there is lots of baitfish and diving birds around and when within one kilometre of a river, the NSW government advises.
Dr Pepin-Neff said swimmers should be mindful in warm water and stick to fully enclosed harbour beaches when possible.
No shark-related deaths have occurred in Sydney Harbour since 1963 but a 35-year-old man was killed by a great white shark while swimming at Little Bay beach in Sydney's east in 2022.