The group maintains 2040 traps in a 500ha area they hope to rid of pests so that kiwi can thrive.
"We all want to restore what we call the mauri, or the life force, back to the forest by trapping all these introduced mammals," Schmid said.
They've caught 7084 rats, 2367 possums, 114 stoats and 95 feral cats in about five years.
An average day involves heading into the bush to "scrape out maggoty rat after maggoty rat," Windust said.
It's hard slog and the family do it voluntarily.
"All of our efforts are done for aroha," said Schmid, who was raised in nearby Waitangi and helped her uncle, a forestry foreman, shoot possums as a child.
"The wildlife, they don't have a voice and I want to be their voice. Slowly they are being pushed out of their homes making way for big condos and big development schemes.
"It would really annoy me and make me feel embarrassed if people were to go 'oh are you a Kiwi' and I said 'yes but all the kiwi are now extinct'. How could you call yourself a Kiwi if there isn't any kiwi around?"
Windust, a beekeeper by trade, was inspired to get into conservation when he was fishing on the East Coast with a friend and realised hundreds of pohutakawa along the coast line had died.
"I couldn't believe it and I realised it was possums killing them and started trapping possums. Then I bought land in Paihia - 120acres of bush - and I realised that the northern rata were doing the same thing, they were all getting killed by possums," he said.
Windust started doing pest control on his own property, which backs on to the Opua State Forest, and noticed the "whole forest was collapsing, thousands of trees dying".
So he set up the Bay Bush Action charitable trust and got a management agreement with Doc to trap a 500ha area.
He was looking for a flatmate and when Schmid and then 2-year-old Miller came to live next door they started helping him.
Now Schmid lives in a cabin on her own patch of land in the bush gifted by Windust.
Their efforts are starting to deliver a return, with native birds beginning to thrive again.
"When we first moved here there was no dawn chorus and now there's so many tuis, way more moreporks and at night we're starting to here kiwi again. Not only that, all the forest that was just skeletons is now coming back to life," Windust said.
They hope to re-introduce an array of native wildlife to the area - kokako, kaka, giant kauri snails and saddlebacks - but will start with kiwi.
There's currently only a handful of pairs in the Opua State Forest, but the organisation Kiwis For Kiwi planned to bring in about 20 birds from other areas to improve genetic diversity, Windust said.
"We hope to have kiwis pecking around in people's compost bin in their back yard. We want so many that they're just everywhere.
"They breed as fast as possums and the forest should be absolutely full of them and that's what we want to see happen."
Windust said many of the coastal kauri forests up north had been cleared and Opua was one of the few intact.
"We've only got the scraps left and we need to protect them."
How you can help save the kiwi
• Set traps for rats, stoats and other pests in your own backyard
• Donate to charities involved in kiwi conservation
• Volunteer with a local group
• Get your dog "kiwi aversion" trained
• Buy a Kuwi the kiwi book by Kat Mereweather - a portion from each one sold goes toward kiwi conservation
