Westpac Life Saver Helicopter's Lifesaver 3 at Seamen's Hut, as the search for Canadian bushwalker Prabhdeep Srawn continues (from @Lifesaverhelo on Twitter).

Westpac Life Saver Helicopter's Lifesaver 3 at Seamen's Hut, as the search for Canadian bushwalker Prabhdeep Srawn continues (from @Lifesaverhelo on Twitter).

A land and air search for missing Canadian bushwalker Prabhdeep Srawn will begin again on Thursday, a day after reports of voices or a dog's bark within the Kosciuszko National Park.

A NSW Police spokeswoman said crews would remain in the area overnight after the search was scaled back because of poor light on Wednesday.

The Westpac Life Saver and the Snowy Hydro SouthCare rescue helicopters joined police, State Emergency Service volunteers, National Parks and Wildlife Service officers and locals involved in the search, as hopes for the 25-year-old appeared to fade as fresh snow and freezing conditions were again expected.

Prabhdeep Srawn, 25, the Canadian bushwalker missing in the Kosciuskzo National Park

Prabhdeep Srawn, 25, the Canadian bushwalker missing in the Kosciuszko National Park Photo: Supplied

The Bond University law student

and Canadian Armed Forces master corporal parked a rental car in the Charlotte Pass Village on Monday, May 13.

The car was due to be returned on May 15; Mr Srawn was believed to be travelling to Melbourne.

On Wednesday afternoon, crews searched the remote areas around Lady Northcote Canyon and Etheridge Ridge, including the Opera House and Seamen's huts, following reports of noise in the area.

Crews used thermal camera technology but failed to find Mr Srawn.

His parents travelled from Ontario, Canada, to Jindabyne this week, waiting for news with their daughter and son-in-law as well as Australia-based relatives.

The family made no comment on Wednesday, while US-based relatives said they had declined contract offers from an Australian current affairs program for an exclusive television interview.

They continued to maintain an active social media presence calling for prayers and awareness.

Family member Tej Sahota, a doctor based in Ohio, said Mr Srawn had extensive cold-weather camping experience from the Canadian Army and may have taken shelter in areas of bush or a gully.

''He may not make it out tonight but we're hopeful food and medications can get to him,'' Dr Sahota said. ''From a physician's perspective, it will take a few days. He'll be malnourished, hypothermic and hypoxic.''

Dr Sahota said Mr Srawn would probably have suffered from frostbite.

Peter Hosking, of the Kosciuszko Huts Association, spent Wednesday with Mr Srawn's family and said they remained positive going into the 10th day of his disappearance. ''Coming from the perspective of a hiker who does a lot in the area, being lost in those conditions for so long is very extreme,'' Mr Hosking said.

''There is no way of being able to protect yourself from the elements. If he is above the snowline I would class it as around 5 or 10 per cent [chance of survival] and below the snowline at this point maybe 40 or 50 per cent.''

Mr Hosking said search efforts would continue in contours near the Opera House Hut and around the National Park.