The North Island kokako (Callaeas wilsoni) is a threatened endemic passerine whose distribution has declined greatly on the New Zealand mainland due primarily to predation by ship rats (Rattus rattus) and brushtail possums (Trichosurus vulpecula). It persists in 21 populations, of which 10 (48%) have been established by translocation, and 1 has been supplemented by translocation. Of the 11 populations subject to translocation, 4 are on islands and the remainder are on the mainland; 7 translocations have resulted in successful new or supplemented populations and another 4 translocations are in progress. Translocations to another 5 sites did not establish breeding populations for various reasons. In total, there were 94 translocations of 286 kokako to the 16 sites, and the number released at a site averaged 18 (range 3-33) birds. Kokako were released at a site over an average period of 49 months (range 1-159 months) with a mean of 3 birds (maximum 10) released per day. The small numbers of kokako released and the long time required to complete a translocation were due to the difficulty and high expense of catching kokako. Translocations will continue to be important for the conservation of this species, to establish further new populations and to limit inbreeding depression and allele loss in existing populations.
The Maungatautari Ecological Island Trust (MEIT) was established in 2001. In 2006 the ~3,400 ha forested mountain of Maungatautari was protected by a ~47 km pest fence, and most introduced mammals within the fence have since been eradicated. Since then, 7 locally extinct indigenous bird species have been translocated to Maungatautari, one other has self-reintroduced, and many more avian translocations are planned. There are now 20 indigenous forest bird species present (from 12 at the project’s commencement) and the total is expected to eventually exceed 30 species, many of which will be threatened species. Those avian species will be part of a functioning ecosystem that is likely to include at least 50 indigenous vertebrate species (birds, bats, lizards, tuatara, frogs and fish). The avian translocations and the restoration outcome monitoring programmes are described, and some characteristics and values of the project are discussed.
Plumage states of the long-tailed cuckoo (Eudynamys taitensis) are reviewed and summarised from examination of museum study-skins. Besides the distinctive adult plumage (barred above, white background colour below) and immature plumage (spotted above, pale brown below), some birds (13% of those in the wintering grounds, plus 1 bird from New Zealand) show a “transitional” plumage presumed to be intermediate between the immature and adult condition. Also, some pale birds found in New Zealand may represent a hitherto-unrecognised juvenile plumage. A review of distribution records (museum specimens plus published sight-records) in both the summer and winter ranges of the cuckoo confirms a vast fan-shaped distribution extending 6,000 km north from New Zealand to the tropical Pacific, and 11,000 km from east to west in the tropics. Wake Island (19.3°N) in the north, Palau (134.5°E) in the west, Henderson Island (128.3°W) in the east and the Snares Islands (48.0°S) in the south are the extreme records in this range. Records of museum specimens reveal that almost all long-tailed cuckoos returning to New Zealand in October are in adult plumage. Autumn records show a gradual northward retreat of cuckoos within New Zealand, with a stronger-than-average bias in North Island records from March to May. There is no equivalent North Island bias for the spring influx in September and October. Museum specimens from eastern Polynesia exhibited an uneven sex ratio biased towards males (74%), whereas the sex ratio elsewhere was more even. Our study confirms the vast total range of the long-tailed cuckoo and provides age-specific details of the seasonal waxing and waning of the migratory patterns of the breeding population within New Zealand.
Translocation is an important tool for the conservation management of birds in New Zealand. Early translocations marooned endangered species in predator-free environments, typically remote islands. However, modern integrated pest control, coupled with a proliferation of community-based restoration projects, has led to increased opportunities for translocations, particularly to mainland sites. Effective post-release monitoring of bird translocations is vital for improving overall translocation success. Here, we discuss why post-release monitoring is important and how it can be achieved, and suggest methods for documenting and monitoring translocation projects for birds. Key suggestions include: specifying the characteristics of each translocation, including how many birds are released, demographic composition and transfer processes; conducting post-release monitoring using discreet surveys and consistent sensible methodologies; individually marking birds; distinguishing immediate post-release effects from long-term site-related effects; and documenting the results in an accessible format such as a web-based database or published paper. We advocate a strategic approach whereby the intensity of post-release monitoring is directly related to the need and subsequent use of the data collected.