Population boost for Bay of Islands

DoC rangers Ana Mules and Andrew Blanshard carry freshly delivered boxes of popokotea (whiteheads) to their new home on Motuarohia Island during last year's Project Island Song translocation. Photo / Peter de Graaf

The Bay of Islands' native bird population is about to receive a boost with another 80 popokotea (whiteheads) being released this month as part of Project Island Song.

The chirpy, sociable little birds will be caught on Tiritiri Matangi Island in the Hauraki Gulf starting this Sunday. The Project Island Song team will then transport the birds by helicopter to Moturua and Urupukapuka islands where they will be released on April 23.

A popokotea (whitehead) makes a break for freedom on Motuarohia Island (Roberton Island).

Project coordinator Richard Robbins said it was likely to take a week to catch all 80 using five-metre-long mist nets. The birds flew into the nets then dropped into pockets at the bottom where they could be carefully collected. The team hoped to catch a mix of male and female, juveniles and adults.

Popokotea are the most common bird on Tiritiri with a population of about 3000. The birds were expected to thrive on Urupukapuka, which was about the same size as Tiritiri. It was not clear why popokotea became extinct in Northland more than 100 years ago but it may have been a combination of pests and disease, Mr Robbins said.

Until recently the only surviving population north of Auckland was on Hauturu or Little Barrier. The first batch of popokotea were released on Motuarohia (Roberton) Island last May.

Another reason for wanting to bring back popokotea was that they were the only North Island hosts of the long-tailed cuckoo, a tropical visitor that laid its eggs in other bird's nests. If popokotea became established in Northland the long-tailed cuckoo would return of its own accord.

The team heading to Tiritiri will include translocation expert Kevin Parker, half a dozen volunteer bird handlers and kaimahi (workers) from Te Rawhiti hapu.

In May the volunteers hope to catch 40 toutouwai (North Island robins) in Pureora Forest, near Lake Taupo, then release them on Urupukapuka Island.

Mr Robbins said the toutouwai release was complicated by the birds' fiery, highly territorial nature. Unlike the popokotea they could not be transported five to a box; instead, they would have to be transported by camper van in individual boxes before being allowed to rest for a night and being taken to the island by boat.

Project Island Song started in earnest in 2009 with the eradication of pests on the Ipipiri islands of the eastern Bay of Islands. The long-term aim is to restore the islands' native wildlife and bring back the dawn chorus, hence the project's name. Species reintroduced so far include pateke (Urupukapuka, 2012); toutouwai (Moturua, 2014); popokotea (Motuarohia, 2015); and tieke/saddlebacks (Urupukapuka and Moturua, 2015).