As the Department of Conservation gears up for another large pest-control operation Samantha Gee finds out if the last one worked and what the future of predator control looks like.
A small yellow insect-eating bird with a loud melodious call is what first drew Graeme Elliott into the world of New Zealand's native birds.
Elliott, a self-confessed "nerdy little birdy kid" was raised in Christchurch and spent family holidays in Nelson where he remembers climbing Mt Arthur to look across the huge expanse of Kahurangi National Park, and wonder what was out there.
"When I was a kid I suppose there probably was still a kakapo out there and I thought, there might be a kakapo, there might be a saddleback, there might be a kokako, they were kind of these rare and elusive creatures."
The Department of Conservation scientist says when he looks out across the second largest national park in the country now, he knows what isn't there.
Elliott paints a bleak picture of indigenous bird life in New Zealand. Without "intensive intervention" he says our native birds will continue to decline until they are extinct.
"I've always thought about the forest and the backcountry as the place where all our native animals lived and yet you realise now you go out into the Kahurangi National Park and you realise they don't live there any more, for the most part they have gone."
When he first began working with native birds in the 1980s, Elliott says there was a general acceptance that the species that were going to become extinct were already on their way out.