It will ensure funding levels are maintained at the same level as in 2017, when the then National Government announced a $21m one-off "Battle for our Birds" package because it was a mast year.
The Government spends about $70m a year on predator control but that has been boosted in "mast" years when trees produce a lot of seed, resulting in a population boom among rats, stoats and possums.
Sage said the funding would ensure that level of control could be maintained every year. That would help reduce predator numbers in non-mast years rather than trying to control it in mast years.
"For the first time, predator control funding will be locked in. Budget 2018 means DoC won't have to divert funding from other priorities or scramble to get one-off allocations from Government in order to do this essential work," Sage said.
Predators have been blamed for killing about 25 million birds each year as well as destroying habitat. It is controlled by 1080 drops and bait stations to traps.
Some of the funding would also be used to develop new methods of predator control, such as through technology.
Further conservation related announcements are expected in the Budget under the Green Party's support agreement with Labour.
Sage was sceptical when the former government announced the Predator Free by 2050 programme in 2016, saying it lacked a plan and funding commitments given it largely relied on funding from private sources.
That programme was to make one million hectares of land predator free by 2050. It included $28m to set up a joint venture to identify large scale eradication projects and attract private funding, which the Crown would match with $1 for every $2 put in by businesses, charities or community groups.
On the campaign trail, former National leader Bill English promised a further injection of $70m about $40m of which would go toward funding community groups to undertake pest control. The rest was to go to DoC and about $2m a year was to create a hit squad of Doc rangers to advise communities on pest control.
The current predator control programme places emphasis on the habitats of 10 birds that are considered threatened and highly vulnerable to predators. They are the kākā, kea, kōkako, tokoeka, brown kiwi, kākāriki karaka (orange-fronted parakeet), tuke (rock wren), whio (blue duck), mohua (yellowhead), and the weka. The habitats of Archey's frogs and the short-tailed bat are also targets.