The Department of Conservation is cutting 140 jobs in the latest round of restructuring.
DoC's 1800 staff were briefed at meetings around the country on Tuesday.
DoC director general Al Morrison says the department is being reorganised, with six new regions replacing the existing 11 regional conservancy boundaries.
This will result in the loss of about 118 regional management and administrative positions and 22 jobs in operational areas, including asset management and inspections.
Mr Morrison says the changes will ensure DoC meets its $8.7 million savings target but will not compromise its core work.
He says there are no plans for further major restructuring but is not ruling out future job cuts
He told Checkpoint the department is removing fragmented part-time management positions and replacing them with full-time staff.
Mr Morrison says the department needed a structure regardless but acknowledges it would not be cutting jobs if it was not under budget pressures.
He says it is confident the cuts will not affect DoC's conservation role.
Mr Morrison says staff are being consulted before final decisions are made and any changes will not take effect for some months.
Cuts budget driven, say Greens
The Green Party says the job losses are all about budget cuts.
Mr Morrison says DoC would go ahead with the new structure, even if its budget was doubled tomorrow.
But Greens' conservation spokesperson Eugenie Sage says there would be no need for job cuts if the department was funded adequately.
Figures obtained by Radio New Zealand show the department has been struggling to maintain its statutory role of protecting the environment since 96 jobs were cut last year.
The number of DoC submissions on resource consent applications fell from 98 in 2011 to 48 the following year.
Fish and Game director Bryce Johnson says DOC is doing less on these sorts of issues, leaving it to environmental groups to "carry the can" for advocacy on water quality issues.