The company announced on Tuesday afternoon that it had informed the NSW government – a partner in the project –that the trial would end three years early.

Two sea cages at the Marine Aquaculture Research Lease (MARL), seven kilometres off Hawks Nest, were badly damaged in heavy seas in January last year. 

One lost its entire population of 20,000 predatory yellowtail kingfish, sparking outrage from conservation groups and local tourism operators who called for the multi-million project to be shutdown.

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Up to 17,000 predatory yellowtail kingfish, used to being fed automatically, were left hunting in the marine park waters after about 3000 fish were recaptured.

News of the damaged farm made it around fishing circles at lightning speed with commercial and recreational fishers cashing in on the “kingy mayhem”. 

Huon’s chief executive Peter Bender described the trial on Tuesday as a “success”.

“We have learnt a lot about how to farm high-quality yellowtail kingfish in warm water as well as farming in a highly exposed site,” Mr Bender said.

“We are now in a position to pursue commercially farming kingfish off the Australian coastline, which is the very outcome that the trial set out to achieve – this result truly is a credit to everyone involved.”

Huon retains a commercial 62-hectare lease near the trial site but the company said it did not plan to farm it “for the foreseeable future”.

According to Huon, independent environmental sampling undertaken in the two years of trial found “no significant impact on seafloor ecology or water column chemistry”.

A spokeswoman said the moorings, marker buoys and all equipment would be removed from the trial site, disinfected and taken to Tasmania.

The Newcastle Herald revealed in October last year that the pen damage that resulted in the mass kingfish escape was caused by Huon’s failure to maintain and clean the fish-farm “fortress pens”.

An interim incident report, put together by an independent investigator in conjunction with Huon and the Department of Primary Industries, identified serious maintenance issues at the farm that led to the escape.

Predator nets on two of the pens had not been cleaned since they were installed, or more than a year, leading to a large buildup of barnacles and weed causing structural problems in heavy seas.

Net cleaning is meant to be carried out either weekly or every two weeks depending on the size of the mesh used.

Four bronze whaler sharks got trapped in one of the fully stocked sea cages. When efforts to remove two of the sharks failed, they were killed.

The interim investigation found that the design of the “fortress pen”, when correctly rigged and maintained, would have been able to withstand the weather conditions in January 2018 caused by two low pressure systems off the coast.

Vocal critics have long held the view that the farm should not have been approved in the marine park, which is a main thoroughfare for migrating humpback whales.

Marine Parks’ Association chairman and whale watching tour operator Frank Future said the decision to scrap the trial early was a “big win” for the marine park.

“I’ve been suspicious of the whole project since day one, the marine park environment is just too important to risk,” he said.

“There have been a few shots at fish farming in this area now, propped up by public funds, and they have all failed.

“We really hope they don’t try it again. The money should be invested in looking after our wild fish stocks, not aquaculture.”

Mr Bender said ongoing challenges with the trial included sourcing commercial quantities of yellowtail kingfish fingerlings and the lack of a suitable harvest site to ensure a stable market supply of fish.

He said Huon would continue to explore kingfish farming sites elsewhere in NSW. “We’d ultimately like to have kingfish farming sites on both the east and west coasts of Australia so that we can supply locally-grown kingfish to the domestic and export markets, as well as locals.”

The commercial-scale kingfish trial at Providence Bay included five pens, each about 60 metres across.

Last year was a difficult year for Huon. In May, storms caused a fish pen to break apart in Tasmania, releasing 120,000 Atlantic salmon into the wild.