Trapping ring key to increased kiwi numbers

Since April 2014 a chain of nearly 150 mustelid traps on properties surrounding Marunui Conservation in the Brynderwyns has provided a protective buffer to the 43 Northland brown kiwi released there between 2013-2015.

“This ‘Ring of Steel’ has been a huge success with hundreds of predators having been eliminated over the past three years,” says Marunui’s John Hawley. “These include ferrets, stoats, feral cats, weasels and rats. While we trap intensively within our 423 hectare property, these other traps expand the area under predator control to 1350 hectares. They help protect those kiwi that have established territories further afield and reduce predator invasion into Marunui.”

Mustelids are a major threat as ferrets can kill adult birds, while stoats are responsible for the death of most kiwi chicks in the wild. Feral cats also prey on chicks. In 2016 the combined catch of the two contract trappers was 25 stoats, 76 weasels, 357 rats and 5 feral cats. In addition Mangawhai Tracks Charitable Trust volunteers caught several stoats in the DOC Reserve.

Trapping has been fortnightly since December as the summer period is the time when stoat kits are dispersing and the protection of recently hatched kiwi chicks is paramount. In January this year ten stoats were caught in the Ring while two were caught in Marunui along with three feral cats.

“Every stoat caught increases the chances of chicks surviving to maturity,” says John Hawley. “Oscar and Tom are due to hatch any day and since August 2013 there have been 22 monitored nests, with generally two chicks hatched per nest. The trapping buffer has been vitally important to their protection and to unmonitored nests. There is no doubt that kiwi numbers are increasing as a result.”

The project has been made possible by funding received from the Biodiversity Condition Fund and Hancock Forest Management (NZ), traps supplied by the Department of Conservation and Hancocks, the cooperation of landowners, and support from local businesses. John says this combined effort demonstrates what can be achieved and notes it has encouraged other groups to start trapping, some as far away as McKenzie Cove near Langs Beach.

“The future for kiwi in the Brynderwyns and wider area looks very positive.”

DEADLY: Kiwi predators like stoats, weasels and rats are falling prey to a protective Ring of Steel.