National's erosion of Department of Conservation (DOC) funding has led to "major species decline" and a strain on facilities, the Green Party says.
The party claims 142 species have moved closer to extinction since National came to government, including the kea, antipodes wandering albatross and flesh-footed shearwater.
Green Party conservation spokesperson Kevin Hague says DOC has missed out on $336 million since John Key became Prime Minister.
"National's spending on conservation has been on average $56 million less per year than the last Labour government's.
"Under National, DOC has been increasingly reliant on the corporate sponsorship for key projects. Four birds -- whio, kakapo, takahe and kiwi -- have corporate sponsors to help with their recovery."
Mr Hague says the cuts also put strain on frontline staff, who are already under pressure from the "tourism boom".
"The Government cannot expect tourism to flourish if our facilities are not up to scratch. It's only a matter of time before something somewhere goes seriously wrong or becomes dangerous."