"As public servants, it is inappropriate for DoC staff to be involved in an activity that forms part of a clearly stated campaign to change Government policy and we have simply reminded staff of this fact," said Mr Newsam.
"We follow the standards of the State Services Commission's (SSC) guidelines and we recommend our staff do that too," he said.
He believed DoC had issued the reminder only to its Buller staff.
Asked if they could lose their jobs by attending the bioblitz he said if staff breached the SSC guidelines then appropriate steps would follow.
If any new species were discovered on the bioblitz the discoveries would be treated like any other new scientific finding, regardless who made the discovery.
According to the Forest & Bird website, the event - in two weeks - is over-subscribed and registrations have closed.
Meanwhile, a DoC decision on whether the Denniston Escarpment Mine project can go ahead has been delayed.
The original hope was that a decision would be made early this year, but it is probably still some time off, said Mr Newsam.
Without a concession and an access agreement from DoC, Bathurst Resources will be unable to open a coalmine on public conservation land even if it wins an appeal against gaining resource consent.