Conservation Minister Maggie Barry is giving the credit to aerial use of 1080 and continuing trapping for a 1000-plus per cent increase in the kokako population in Kauri Coast forests.
"An aerial 1080 drop in 1990 is credited with saving the kokako from local extinction, and its continued use, along with trapping, has seen the population grow from a low of five pairs in 1990 to 60 pairs today, as well as 29 single birds," Ms Barry said.
"Without sustained predator control these birds wouldn't survive in the Waipoua, Waima and Mataraua forests, and the fact that they have become one of the most robust managed populations proves yet again the value of 1080 in knocking down rats and possums.
"The increase in kokako shows what's possible when you keep predators down, and proves how vital it is that we achieve the ultimate goal of Predator Free 2050."
Many kokako pairs had been seen with juvenile birds over the last breeding season, she said, adding that an 1100 per cent increase represented significant success. Rat and possum control included four aerial 1080 operations in Waipoua alone between 1990 and 2014, plus trapping.
The Department of Conservation had used a bait station network to control rats and possums, and a stoat trap line that had grown from 300ha to 913ha since 21003.
"No other bird evokes our ancient forest like the kokako. It has the most haunting birdsong in the New Zealand bush," Ms Barry said.
"Research during the 1990s identified key predators and how to manage them specifically for kokako, and that information is still in use at Waipoua, Mataraua and Puketi.
"We have the exciting and realistic opportunity to not only protect these kokako populations, but to grow them so that Northland is once again a national stronghold for this taonga of the forest."
Meanwhile Ms Barry, who met with local groups at Kerikeri's Aroha Island Ecological Centre on Saturday to discuss Predator Free 2050, declared herself ("with pride") to be Cabinet's biggest killer, given the number of death warrants she had signed for rodents, stoats and possums.
Ms Barry explained how PF2050 would work in Northland, through a range of community, corporate and government partnerships.
The Ministry of Conservation had funded the region an extra $300,000 this financial year, and would provide grants up to $10,000 for local strategies.
Improvements in and safer application of 1080 had led to wide acceptance of its use in areas where ground trapping was not practical, she added, but for her the goal included establishing a toxic-free environment as well.
As part of its commitment to the 2050 target, DoC had employed nine rangers to identify regional needs, help set up 'trap libraries' and other shared community resources, and liaise with iwi, community groups and agencies.
Northland Predator Free ranger Fleur Corbett spoke about work already being done in Northland, much of it through alliances between community groups.
"As a region we can be hugely proud of all this work. If we can get even more people involved we'll be well within range of being predator-free by 2050," she said.
Northland Forest & Bird advocate Dean Baigent-Mercer refused to attend Saturday's announcements, however, his organisation having highlighted "ongoing crises" such as the collapsing Russell State Forest in 2015.
"We pointed out clearly that Northland DoC alone needs an extra $10 million to $20m to turn around the collapse over the next decade," he said.
"I am not going to praise a minister for crumbs when DoC is actually doing so little, and the community and hapu are carrying the greatest extent of the work in Northland."