Improving the ecosystem for Kokako habitat

The Kaharoa Kokako Trust has been successfully working to save a population of kokako in 700 odd hectares of native forest since 1997. Pine plantations managed by PF Olsen are adjacent to the area so the Trust was delighted when contacted by Sally Haddon, Environmental forester at PF Olsen, with an offer of assistance.

After some discussion the assistance took the form of providing a thinning crew to help remove wilding pines over successive summers.

The history of the block includes some prior private ownership at which time a small block of Radiata pine was planted plus numerous scattered trees over a number of years. The main block was harvested for DOC by PF Olsen a few years back. They did a great job at limiting damage to the existing remnant regrowth bush in the block which is now successfully returning to native bush with a nice diversity of species.

But the remnant scattered pines, some over a metre in diameter, posed a problem as source trees for on going pine seedlings and some were overhanging bait line tracks and roads posing a potential safety/access issue.

For those who have been involved in trusts such as the Kaharoa Kokako Trust it will be no news that money is hard to come by so it is difficult for us to obtain funding for jobs that are not seen as 'essential' to the core objective of saving kokako despite the fact that the entire ecosystem has to be protected to effectively carry out that principle aim. It will also be no surprise that volunteers for conservation trusts typically have grey (or no) hair so the more physical tasks are well beyond them even where they have the experience. Volunteers had played at poisoning trees where they were not close to access ways but were really making little headway.

In two summers the crew has cleared well over 50% of the worst areas of standing trees. Many were felled but in some areas ring barking was undertaking to leave trees standing. There were two reasons for this. Firstly this reduces damage to surrounding vegetation. Secondly, in one large area there were no other tall trees so kokako were using the pines as 'call trees' where they sing in defense of their territory.

It takes a surprisingly long time for a large ring-barked Radiata pine tree to die (over 9 months in some cases, including a drought) but the results now are extremely satisfying.

The Trust is delighted with our relationship with PF Olsen both as a company and with individual staff. The company provides us with sponsorship on an ongoing basis and then comes up with a bonus Christmas present like this! Truly a great example of merging the corporate world with the community and the result is another step on the way to enhancing the home of New Zealand's fourth largest population of this iconic bird.

Ring-barking and poisoning unwanted pines growing in the native forest avoided damage that would have resulted from felling the trees and provided 'call tree' for the kokako.

Testament to the toughness of Radiata pine, the larger trees took a surprisingly long time to die.