One such volunteer is Beachlands resident Kevin Sargent, a former building inspector, now semi-retired. Each Tuesday morning Kevin meets up with a team of 8-10 others, to get his pest lines for the day and fill his backpack with bait.
"I'm usually in the bush for around four hours, going at my own pace, enjoying the peace and seclusion you find only in the bush and seeing birds like kereru, kaka and kokako.
"I once sat down for lunch under a tree and there was a kokako right above me!
"I also like meeting other volunteers - we are all down to earth people who just like getting outside. I'm happy to say I get a great feeling of satisfaction driving home after a day's volunteering."
The efforts of Kevin and his fellow volunteers are having a significant impact. Surveys to see how many kokako pairs there are in the area consistently show that the population is increasing.
When pest control first started the population had fallen down to as low as one female and around 24 males.
With females doing most of the egg sitting, they are far more vulnerable to predation by rats, possums and stoats. By 2010 there were 25 pairs.
"It is ambitious to cover this kind of area, especially as we can only survey on sunny and still mornings, but we really need to find out where the birds are so that we can see how well the population is doing, says pest control expert Dave Bryden.
"To find the birds we walk tracks and every 200 metres play a tape recording of a kokako singing. We then wait 15 minutes to see if any birds in the area reply.
Bryden, who also runs the Kokako management area surveys, points out that the work is slow going, so volunteers don't need to be super fit.
"But they do need to be early risers, have good hearing and be confident in the bush. We do the surveys on week days and weekends, so this enables people who work during the week to get involved too."
If you like tramping in native bush with a satisfying blend of discovery and adventure, council needs your assistance in the Hunua Ranges.
Contact Mags Ramsey on 09 536 7012 or email mags.ramsey@aucklandcouncil.govt.nz to volunteer or to find out more information.