Earlier this week, Chris Allchin and his friends embarked on a mission to catch “something big” while fishing near Clifton Gardens on the northern side of the harbour.

The team was fishing in waters about 20 meters deep, well away from swimming beaches, when they hooked a shark and managed to bring it onto their boat.

The shark, believed to be between 18 and 20 years old, has been handed over to fisheries authorities for research purposes.

Allchin described the experience of reeling in the shark as “a rush,” highlighting the presence of large sharks in the harbour.

“Sharks have always been part of the harbour ecosystem, which is why we have protected swimming areas that are monitored or netted,” Allchin told 9News.

“Many people, myself included, have casually jumped off a boat for a swim in the harbour, unaware of the potential risks lurking below,” he added.

“Hopefully seeing that 150kg bull shark has educated people to swim in designated areas and not in the middle of the harbour.”

They are not a protected species in Australia.

The recent attacks triggered some debate over the shark population, though no cull or other control measure has been ordered.

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