Forest and Bird say hundreds of areas of native habitat around the country are being unlawfully harmed with near impunity.
In a report released today, it said that dozens of local and regional councils were not doing the job they were tasked with, to protect the natural environment.
The environmental lobby group has documented hundreds of instances of what it says is deliberate damage to native habitat.
Data from regional and district councils received by Forest and Bird under the Official Information Act shows some councils lack the ability to even detect the problems.
Forest and Bird chief executive Kevin Hague said New Zealand was currently doing a terrible job of looking after nature.
"This report shows very clearly that nature is under attack on private and public land, and that public agencies are desperately failing in their responsibility to do anything about it."
He said in three years, there had been fewer than 10 prosecutions for native habitat destruction.
"Where councils are aware of large or important tracts of native habitat being illegally sprayed, burnt, cut down, or poisoned, very few of them are equipped to enforce the law to its full extent."
Hague said that meant there was often no meaningful consequence or deterrent for those committing significant environmental crimes.
"Equally concerning is that a third of New Zealand's councils have no records of any unauthorised vegetation clearance in three years.
"Because most councils aren't actively looking to protect vulnerable habitat, it isn't surprising that they would be completely oblivious when damage is caused."
Hague said when councils did become aware of deliberate harm to their natural environment, they were more often than not "toothless in their ability to protect it", either due to weak local rules, or desperately under-powered compliance teams.
"It is clear that in the absence of dedicated staff, resourcing, and consistent rules, New Zealand is losing significant places and species with little risk to the perpetrator," Hague said.
"There is easy money to be made in harming the natural environment and little meaningful deterrent. This is undoubtedly a calculation made by some land-owners and farmers around the country, as this report indicates."
A recently released study of sheep and beef farmers' attitudes to managing biodiversity on their farms showed more than 90 percent supported its merits.
The survey by AgResearch, AUT University, University of Canterbury, and the Catalyst Group, highlighted that many farmers associated a range of values and benefits with biodiversity on the farm, spanning social, environmental and economic themes.
As part of a study funded by the Biological Heritage National Science Challenge, 500 farmers around the country took part in the survey that was published in the New Zealand Journal of Ecology.
Auckland University School of Biological Sciences associate professor Bruce Burns said that while the results showed most wanted land protected for future generations, there were barriers to conservation efforts, such as the cost and time needed to do this.
Hague said there was no guarantee that important habitat would be protected, regardless of its size, importance, rarity, or classification.
RNZ