Rats, stoats and possums kill millions of native birds every year.
For the Department of Conservation, it's a big and expensive problem, with management of just these three predators costing more than $70 million a year.
In its bid to solve this problem, the Government has set a target of pest free by 2050.
Nine-year-old Max Wilson and 13-year-old Callum Stewart have set themselves a similar target.
The enterprising young conservationists have made it their mission to clear their local Long Bay wetlands of pests.
Check out how they're doing it by watching the video above.