Birdsong on speakers to help kokako breeding

Sound speakers playing birdsong are being used to try to re-establish one of New Zealand's most endangered birds in forest land west of Auckland.

A pair of kokako are being relocated to the Waitakere Ranges from the Pureora Forest in the central North Island following intensive pest control efforts by the Ark in the Park project.

They would be the first kokako in the Waitakere Ranges in more than 60 years, and it was planned to release up to 30 kokako into the ranges in the next two years.

The birds protected their territories of about 8ha by singing and chasing away invaders, Ark in the Park chairman John Sumich said.

They planned to use sound anchoring technology to encourage the birds to establish in the areas around the sound anchoring point, he said.

"Kokako from different areas have different dialects, so it's important to give them a feeling of familiarity by broadcasting their song at certain points in the forest," he said.

"Speakers will play songs from the two populations used for the Ark in the Park transfer and we will monitor the behaviour and dispersal of the birds in relation to this.

"Although kokako speak different dialects, from our understanding they're not fussy if their partner doesn't speak the same language, so we're anticipating there will be cross-breeding amongst the populations.

The technique had proved successful in the past, Mr Sumich said.

About 750 pairs of the blue-wattled kokako remained in the North Island, plus a few more on offshore islands.

The Department of Conservation aimed to have about 1000 breeding pairs established by 2020.

Kokako were already present in the Hunua Ranges southeast of Auckland city.

- NZPA