KIM LANDERS: Experienced fire management staff who've been made redundant by the New South Wales Government say they're being asked to return to help fight fires - without pay.

As the bushfires continue to burn, the former staff are being used to help manage vast areas of national parks that have been affected by the blazes.

Isobel Roe reports

ISOBEL ROE: It's the toughest bushfire season many firefighters have seen.

Last week as several fires flared to emergency level for a second time, New South Wales Emergency Minister David Elliott wanted everyone available on the job.

DAVID ELLIOTT: It is very much, pardon the pun, all hands to the pump.

ISOBEL ROE: AM has learned even some of those who've been made redundant by the state's National Parks Department are back on the fire ground - working for free.

STEWART LITTLE: I think you have a great deal of irony there, isn't it, that people made redundant are now they are basically being asked to come back and work.

ISOBEL ROE: Stewart Little is the general secretary of the Public Service Association, and represents many former National Parks and Wildlife staff, who lost their jobs as a result of budget cuts.

STEWART LITTLE: A lot of senior rangers, area managers, people with remote area experience, these are highly trained people who are able to be winched into remote locations to put in hazard reductions and backburning during wildfires.

Certainly, I know of quite a few that have gone back.

ISOBEL ROE: AM has spoken to one former staffer made redundant last year, who didn't want to be identified.

He told the ABC he's doing a similar job but now he isn't being paid and he knows of at least a dozen others who are volunteering their time managing the fire response, through the Rural Fire Service.

Stewart Little says he's not surprised former staff want to help.

STEWART LITTLE: You know, people in those jobs, I mean, you don't become a park ranger because you are going to make heaps and heaps of money but it is vocation.

I mean these are people who are committed to the environment.

ISOBEL ROE: The New South Wales Government cut $121 million from national parks in the 2016-17 budget, resulting in the loss of about 100 ranger jobs

Another $80 million was cut in the latest budget.

In a statement to the ABC, the National Parks and Wildlife Service said:

STATEMENT FROM THE NATIONAL PARKS AND WILDLIFE SERVICE: We are aware of one former National Parks officer who volunteered for four days providing advice to the incident management team.

ISOBEL ROE: The statement went on to confirm that other former parks staff are volunteering to fight fires through the Rural Fire Service.

Gary Dunnett is the executive officer for the National Parks Association, a lobby group which aims to protect the state's vast network of conservation areas.

GARY DUNNETT: You know, it is about 35 square kilometres per officer. They're really thinly spread on the ground. Areas that really shouldn't be burned at all have gone up in flames.

ISOBEL ROE: Do you think that is something that management of the parks could have somehow prevented?

GARY DUNNETT: No, I think it is something that is an inevitable consequence of the level of drying that we've seen across the landscape.

ISOBEL ROE: The National Parks and Wildlife Department has told AM it'll review its deployment of resources as the season unfolds, taking into account the extent and nature of fires over the next couple of months.

KIM LANDERS: Isobel Roe reporting.