The Ruined Castle bushfire is burning between the Green Wattle Creek bushfire and the Gospers Mountain fire. Fires have burnt hectares of world heritage area having a major impact on flora and fauna.

The Blue Mountains World Heritage Area and the Kanangra-Boyd National Park are home to populations of threatened glider species.

"The more severe wildfires will kill a large population," Dr Smith said.

Scientists like Dr Smith have been working with the Kanangra 2 Wyangala (K2W) Glideways project to document the populations and habitats of glider species.

The project is across Wombeyan, Copperhania, Abercombie, Gillindich, Wyangala and Gillindich-Wyangala reserves. The areas are home to five of the six species of gliders including threatened species.

The Greater Glider and the Yellow-Belly Glider are both threatened, as is the smaller Squirrel Glider. There are also populations of Sugar Glider, as well as two different species of Feather Tail Gliders which could occur along the K2W corridor and world heritage area.

He said it's not looking good.

"If they aren't killed in the fire the larger gliders [Greater Glider and the Yellow-Belly Glider] which feed on eucalyptus foliage will find it tough after severe wildfires."

However, after the fires they will recolonise, he said.

"Little populations can survive the fires and will gradually recolonise from those areas.

"There are good populations out along the Kanangra-Boyd to Lake Wyangala and they could be quite important after the fires to recolonise in the world heritage areas.

"They are small populations, but it might be that these populations survive," said Dr Smith.

He said there is no contingency plan to remove the species which are difficult to catch.

He urged people to contact WIRES or wildlife care organisations if they find animals attempting to escape the fire or injured animals. He also suggested putting out water bowls for all native species.