Dogs pose threat to Tamahunga kiwi

Tamahunga Trapper chair Dave Wilson captures a kiwi for a transmitter change.

More than a decade of predator trapping efforts and years of negotiations with the Department of Conservation (DOC) will soon allow environmentalists to start translocating kiwi to Mt Tamahunga from next year.

But Tamahunga Trappers stress they will need the cooperation of local dog owners to make the introduction a success.

The group says the mountain and its 800ha of forested area as the most significant ecological site between Auckland and the Brynderwyn, and substantially larger than the Tawharanui Open Sanctuary.

Years of trapping efforts on the mountain have successfully seen the voluntary return of bellbird, kaka and tomtit.

Trappers first approached the DOC in 2015 to add kiwi to the list of native birds brought back to the mountain, but pulled the plug on their own application when they realised that more work needed to be done.

They re-applied in 2018 and have spent the last two-and-a-half years convincing DOC that they had appropriate measures in place to ensure the survival of translocated birds. They finally got the go-ahead last month.   

Those measures have been bolstered by the Forest Bridge Trust, which will extend trapping efforts in a 3km buffer zone that will ring the Tamahunga forest.

The resettlement of kiwi is due to start in April next year, but before then trappers will contact dog owners in Matakana, Pakiri, Leigh and the Whangaripo Valley. They will be alerting them to the dangers posed to kiwi by dogs and encouraging them allow their dog to undergo free kiwi aversion therapy.

Trapper community liaison officer Marguerite Vanderkolk says 60 per cent of adult kiwi deaths can be traced to dog attacks and all dogs – from poodles to hunting dogs – pose a threat.

She says dogs are attracted to kiwi by their strong smell and will snatch them and repeatedly shake them until they are dead.

In kiwi aversion therapy, a dog with a special collar around its neck is exposed to a kiwi. If the dog shows too much interest in the bird it receives an electric shock via the collar.      

Ms Vanderkolk says the shock is no worse than that of an electric boundary fence, and a typical aversion therapy session lasts no more than 10 minutes.

A kiwi aversion therapy information day for dog owners, featuring representatives from  DOC, Auckland Council and Ngati Manuhiri, is planned at Matakana Hall on October 10, from 1pm to 4pm.

Afterwards, aversion sessions are expected to take place at Matakana’s Jubilee Park in November.    

Ms Vanderkolk says there is bound to be some resistance from some dog owners but believes most would be horrified to find their dog had killed kiwi.

Translocation project lead Sue Cameron adds that dogs have been known to kill more than a dozen kiwi in one night, which could easily wipe out a population of resettled birds.

In addition to aversion therapy, trappers will be reminding owners that they should always know the whereabouts of their dog, they should not be allowed to roam freely at night and dogs need to be kept on a lead when they are anywhere near conservation land.    

Kiwi disappeared from Mount Tamahunga in the 1980s. Their demise followed the collapse of the ferret fur trade and the subsequent release of thousands of ferrets from farms into the wild. Ferrets that survived preyed on New Zealand’s ground-dwelling birds, which suffered steep population declines.

Translocated kiwi will be sourced from Tawharanui Open Sanctuary and Moturua Island. The first 10 will be transferred next year, 10 more in April 2023 and a further 20 in April 2024.

Birds will have radio transmitters attached to their legs so their movements can be monitored.

Tamahunga Trappers is eager to hear from fit volunteers keen to assist with trapping and those who would like to learn how to track birds via radio. Email tamahungatrappers@hotmail.co.nz.