The NSW Forestry Corporation failed to properly search a forest for endangered greater gliders before logging their den trees, a watchdog has alleged.
The Environment Protection Authority has issued successive stop-work orders against the state-owned corporation over its conduct in the Tallaganda State Forest, east of Canberra.
The latest came on Friday and extends a ban on harvesting in parts of the forest until December 20.
The orders follow the discovery of a dead glider in late August, about 50 metres from where trees were being felled.
The watchdog says it has reasonable cause to suspect the corporation did not conduct detailed and thorough searches to identify all greater gliders and den trees in logging compartments.
It also suspects den trees and the habitat around them were harvested in the compartments, resulting in damage to the habitat of the southern greater glider.
Concerns have been expressed about possible breaches of the Forestry Act and the Biodiversity Conservation Act and investigations are ongoing.
"Our glider surveys confirm that more can be done to protect and conserve this species by identifying and protecting glider den trees and these stop work orders are necessary to ensure that work is done," the EPA said on Friday.
The Forestry Corporation says it's continuing to work with the watchdog and will comply with ongoing directions to stop work.
The corporation recently revealed it conducted pre-harvest surveys for glider den trees in Tallaganda during the day, when the nocturnal animals would have been asleep.
Those efforts identified just one glider den tree.
The EPA later did its own work and easily identified 20 in areas earmarked for harvesting, saying at the time: "we are not confident that habitat surveys have been adequately conducted to ensure all den trees are identified".
The Forestry Corporation has since told AAP it had identified and marked for protection 5400 hollow-bearing trees in Tallaganda, even if no gliders were spotted using them.
During NSW budget estimates hearings last week, EPA chief executive Tony Chappel said he had serious concerns about compliance in Tallaganda.
"... they go to the rigour of surveys and other matters," he said.
He revealed the watchdog is revising protocols to ensure the forestry industry conducts searches in a competent way.
Conservation groups are paying close attention to what's happening in Tallaganda. It's one of the greater glider's last remaining strongholds, with the species losing much of its habitat in the Black Summer fires.