The bellbird's return

Forest and Bird, Volume 22, Issue 2, 1 May 1991, Page 2

The bellbird's return

Mike Lee

HE BELLBIRD OR KORIMAKO is one of three New Zealand honeyeaters — the others being the tui and the rare stitchbird. It is one of our sweetest songbirds. The bellbird is also at the centre of one of our intriguing ecological mysteries: reported as common by early Pakeha observers, it suddenly and inexplicably disappeared from much of the country in the 1860s. In many areas it quickly recovered, but it has never re-colonised the North Island mainland north of the Waikato (with the exception of the Coromandel) or large offshore islands like Great Barrier. Various theories have been advanced to explain the loss of the bellbird from the north. Some suggest an introduced avian disease, others the impact of the tree-climbing ship rat or a combination of factors. Whatever the theories, moves are now afoot to reintroduce the bellbird to areas where it once flourished. Until now conservation managers have concentrated on saving or restoring endangered species in largely pristine ecosystems — usually remote islands. Project Bellbird, on the other hand, was set up to help restore the bellbird to the most densely populated region of the country — greater Auckland. As a first step to regional restoration, Project Bellbird and the Department of

Conservation with the support of Forest and Bird branches have translocated over 110 bellbirds to Waiheke Island since 1988. Waiheke (9,459 ha), 19 km from downtown Auckland, is one of the country’s largest pos-sum-free areas and has significant areas of coastal native forest cover. However, it is also a highly modified environment with an urbanised population of over 6000 and mainland predators like cats and ship rats. Twenty-one bellbirds have come from Kaingaroa in the central North Island with the balance from Cuvier Island. Cuvier or Repanga is a rugged and remote extinct volcano that lies north-east of the Coromandel near the edge of the Pacific continental shelf about 120 km from Waiheke. This former manned lighthouse station guarding the approaches to the Hauraki Gulf

is now a 175 ha nature reserve under the jurisdiction of the Department of Conservation’s Waikato conservancy. Cuvier has been described as a "giant outdoor aviary’. Birds such as the North Island saddleback, red-crowned kakariki and bellbird thrive there in large numbers, secure from predators. In February, Project Bellbird volunteers Dave Lee, Guy Warnam and myself along with Sandra Anderson of Auckland University Zoology department and Liz Humpheries, Rick Thorpe and Malcolm Goad from the Department of Conservation travelled together to Cuvier on the RNZNVR vessel Hinau. DoC’s objectives were to recover any tuatara left on the island for a controlled breeding recovery programme at Auckland Zoo. Auckland University required blood samples from saddlebacks for genetic research on isolated native bird populations. Everybody gave everyone else a hand. In their spare time Project Bellbird members expressed their appreciation to DoC (and Cuvier) by gathering copious quantities of Coprosma berries and sending them to the Tiritiri Matangi nursery for future revegetation of Cuvier’s open areas. Two tuatara were recovered, blood samples from 20 saddlebacks successfully obtained and 60 bellbirds mistnetted in four days. The bellbirds were whisked by an RNZAF Iroquois helicopter to holding aviaries at three locations on Waiheke (Te Matutu Bay, Onetangi and Omiha), where they were held for several days and gradually released into the surrounding bush. To obtain maximum public involvement, an open day was held at Onetangi where Forest and Bird and Kiwi Conservation Club members could quietly observe the birds in the aviary and at their release. In a quiet cere-

mony the birds were welcomed to the island and blessed by senior Maori elder Mr Kato Kauwhata. Ninety bellbirds have been released on Waiheke in the past six months. So far Project Bellbird is going to plan, but are the unknown factors which caused the mass extinction of the bellbird still present? Persistent bellbird sightings from all over Waiheke suggest they are not — but only time will tell. Meanwhile, we are confident that a university-based survey later this year will confirm our belief that the birds are breeding. If we are right, a significant step will have been taken to restore one of New Zealand's most loved native birds to the north. The forest hills and coastal valleys of Waiheke may once again ring to the song of the bellbird. ye