Grey nurse sharks ‘thriving’ at popular dive site but more research needed into critically endangered species

Craig Taylor is comfortable having a shark swim directly at him with its teeth showing.

The 62-year-old has been plunging into the turquoise waters off Shellharbour in the New South Wales Illawarra for decades.

The craggy coastline’s star attraction is the gray nurse shark, and in recent weeks, he has seen more of them than ever before.

“They’re very docile, they will swim up to you and past you.”

Craig stands in wetsuit and SCUBA gear on a rock shelf next to the ocean, holding flippers.
Shellharbour diver Craig Taylor says he has seen more gray nurse sharks than ever at Bass Point in recent weeks.(ABC Illawarra: Justin Huntsdale)

The sharks are listed as a critically endangered species along the east coast of Australia, with only about 2,000 estimated to remain in the wild.

Their numbers first started to dwindle in the 1960s and ’70s, in part due to a spear-fishing frenzy inspired by the blockbuster movie, Jaws.

But Mr Taylor believed their population was on the rise after counting dozens at Bass Point over the past 12 months.

“Even though they build this time of year before they leave for winter, to see this many sharks here is unusual.”

Adam Stow sits inside wearing a sleeveless puffer jacket and blue shirt with his dog sitting nearby.
Biologist Adam Stow says anecdotal reports of large numbers of gray nurse sharks does not necessarily mean an increase in population.(ABC News: Billy Cooper)

Still under threat

Conservation biologist Adam Stow, an associate professor in the school of natural sciences at Macquarie University in Sydney, has been studying the gray nurse shark for nearly 20 years.

He said the species remained under threat of extinction.

“What the gray nurse shark tends to do is move up and down the coast on a yearly basis and they stop at particular aggregation sites up and down the east coast,” he said.

“We need to keep a very close eye on the gray nurse shark because it’s very much at risk.”

Aggregation sites are known gathering points for sharks and are listed as “critical habitat” by the NSW Department of Primary Industries (DPI).

Bass Point was removed as a critical habitat site in 2013, but its rocky gutters and underwater caves continue to attract the shelter-seeking sharks.

An underwater photo of a gray nurse shark swimming past the camera.
Adam Stow says climate change could be influencing where gray nurse sharks gather before migrating to breed.(Supplied: Craig Taylor)

Climate change impacts

Mr Stow said it was important to continue to evaluate and monitor all the existing and potential aggregation sites to understand the recovery of the species.

He said there also needed to be more research into the impact of climate change on their movements.

“There are reasonably long-term shifts in climate, we’re seeing it at the moment, where we’re going through a La Nina phase.

Dissolvable hooks

Trevor Daly, senior fisheries manager for threatened species with the DPI, said a lot of work was being done to track the sharks, monitor their population conserve the species.

“One of the things we would like to look at is whether we can develop, through technology, a dissolvable hook,” he said.

“Quite often they ingest the hook accidentally, the line gets cut off and the shark swims away, but it has still got the hook inside it doing internal damage.

“So, if we can design a new hook, that would probably help the survivability of a lot of gray nurse sharks, and other big fish, that are accidentally caught.”

An overhead looking down photo of bright blue and green water next to a rocky coastline as seen from a drone.
Bushrangers Bay at Bass Point is one of several areas at Shellharbour that is home to gray nurse sharks.(ABC Illawarra: Justin Huntsdale)

‘They’re making a comeback’

The experts agree citizen scientists and divers play a key role in reporting gray nurse sightings.

Craig Taylor remained hopeful the population of the placid creature was stabilizing.

“I think they’re making a comeback – I think they’re thriving,” he said.

“From the mass slaughter days of the late ’60s, yeah, they’re well on their way back.”

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