25 Nov 2021

Restoration - battling predators and planting trees

From Our Changing World, 5:00 am on 25 November 2021

Whistles, song, calls, booms, rustling in the undergrowth, hooting at night. How busy the bush of Aotearoa must have been, this land of birds, before human-introduced predators and tree clearance. Today, two stories of people committed to the restoration of our forests, taking steps towards returning some of this former glory.

A photo of Predator Free 2050's target pests: a stoat, a rat about to break into an egg and and a possum.

Predator Free 2050's target pests: a stoat a rat and a possum Photo: 123rf

Follow Our Changing World on Apple Podcasts, Spotify, Stitcher, iHeartRADIO, Google Podcasts, RadioPublic or wherever you listen to your podcasts.

New lure technology

A photo of Ben McEwen seated at a table with his audio lure system. It's about 30 centimetres high and consists of a thermal camera in a protective casing with a microphone mounted on top. Also pictured is a long reuseable battery that charges the device.

Ben McEwen with his audio lure system Photo: Katy Gosset/RNZ

The battle to save our native birds is heating up with Predator Free 2050 spending $2.4m to enlist fresh scientific talent to the cause.

Department of Conservation figures show 4000 native species are currently under threat, with about a quarter of them in serious danger of extinction.

Predator Free 2050 has now funded six young scientists to come up with new solutions to the problem.

Katy Gosset meets one University of Canterbury student whose intelligent lure system will make it easier to trap predators. Ben McEwen hopes his work will play a role in returning native bird song to the bush.

Planting the polje

Dramatic forest-clad limestone cliffs surround a flat expanse with snakes of gravel - a clue that sometimes water flows through there - the Bullock Creek area just north of Punakaiki is unique in Aotearoa.

This wetland valley of flat ground with steep walls is known as a polje, having formed when a giant cave of series of caverns collapsed. The soft, dissolvable limestone results in unusual hydrology - at times the Bullock flows underground, before resurfacing, and the area is subject to flash flooding. This makes it far from ideal for the farming purpose it was once cleared for.

Conservation Volunteers New Zealand began replanting some of this area in 2020 using Te Uru Rākau, One Billion Trees programme support and are continuing with funding from Jobs for Nature, Mahi mō te Taiao.

Claire Concannon visits the team on the West Coast to learn about this special landscape and find out how the restoration work is going.

The limestone in the Bullock Creek area results in unusual hydrology. Can see a large bush covered limestone cliff with gravel at the bottom.

The limestone in the Bullock Creek area results in unusual hydrology Photo: RNZ / Claire Concannon