Department of Conservation staff have been forbidden from attending a Forest & Bird-initiated "bioblitz" on the Denniston Plateau.
The bioblitz will involve volunteers and scientists scouring the plateau to create a snapshot of its animal inhabitants and ideally discover new species, before a planned 200ha opencast coalmine goes ahead.
DoC staff had been advised by head office that it "would not be appropriate for them to attend the bioblitz", said Buller area manager Bob Dickson.
He had not received any negative feedback from staff about the directive.
DoC spokesman Rory Newsam said because one of the aims of the event was to encourage public pressure on DoC to decline Bathurst Resources' mining application, it was inappropriate for staff to attend, even in a private capacity.