The loss of more than 100 jobs at the Department of Conservation is being seen as hampering efforts to protect threatened birds, animals and fish.
Massey University senior lecturer in ecology and environmental science Mike Joy says Government funding for proper monitoring keeps being stripped away.
Of the country's 10,000 species, 2,788 are listed as threatened, including all mammals, half the birds and 60% of freshwater fish.
Dr Joy says not enough is known about 4000 species, and if there was more time and money available to track them properly it is likely more of them would be found to be threatened.
"Because the Government keeps taking money out of science and out of DoC you don't have the work being done," he says.
DoC says the 102 job cuts being made before the end of the year will mainly be in office-based support roles in the national office in Wellington and the 11 regional conservancy offices.