A total of 730 variable oystercatchers (Haematopus unicolor) were recorded during a survey of the entire 1,500 km coastline of the Marlborough Sounds, New Zealand in spring 2006. This included 347 breeding pairs, 28 single birds and a non-breeding flock of 8 birds. The distribution of oystercatchers was influenced by habitat and human development, with fewer birds found in the inner sounds, where there is most development, and in the exposed outer coastline, where cliff or boulder habitat is limiting. Using similar methods of coastal surveys during the breeding season, the estimated national population of oystercatchers has increased from 2000 birds in 1970-71 to 7000 birds in 2006. This represents a population growth rate of 3.5% per annum. Winter flock counts give lower population estimates and coastal surveys are recommended for future monitoring of this species.
Radio transmitters were successfully attached to 7 male bellbirds (Anthornis melanura) in Kennedy’s Bush and Cass Peak Reserve, Port Hills, Christchurch, during the breeding season. A hand-held radio receiver was used to re-locate them. In addition, we used a grid of 4 remote continuously-operating proximity sensors (radio receivers connected to data loggers) to measure the home-range size of 1 bellbird (#7). Five of the bellbirds were detected regularly within 60 m of the site where they were captured. The other 2 were always detected at least 100 m away. Two of the 5 regularly detected near their capture location were occasionally detected 400–500 m away, in gullies with flowering flax (Phormium tenax) and kowhai (Sophora microphylla). The full home range (100% MCP) of bellbird #7 was at least 3.7 ha, and its core home range (90% MCP) was at least 0.2 ha. Its night-time roost was near the centre of its home range. First departure from the roost was before sunrise and last arrival about sunset. If used more extensively, radio telemetry would be useful for measuring home ranges and detecting long-range movements of bellbirds.
Pterodroma occulta was described by Imber and Tennyson in 2001 and tentatively named Vanuatu petrel. The first specimens of this bird were collected in Jan 1927, east of the island Mere Lava in Vanuatu (then New Hebrides), but their breeding grounds have remained unknown. After several exploratory visits to the Banks Islands I discovered a breeding colony of Vanuatu petrels on Vanua Lava in Feb 2009. Statements that this species breeds on Mere Lava were not substantiated.
A pair of barn owls (Tyto alba) was found breeding in Kaitaia farmland in Apr 2008, and observations on their nesting biology and behaviour were made over a period of 24 months. Another injured young barn owl, possibly from an earlier breeding attempt, was found with the pair at the time of their discovery, and brought into captivity. The nest tree was climbed and 2 dead owlets recovered, but the pair re-nested and 3 young successfully fledged. Pellets and prey remains were collected and their diet is described through pellet analysis. This is the 1st record of wild barn owls breeding in New Zealand.
A new subspecies of Coenocorypha snipe from Campbell I is described and named. This bird was discovered on rat-free 19 ha Jacquemart I in 1997, and had probably been confined there as a breeding species for about 170 years. Norway rats (Rattus norvegicus) were eradicated from 11,268 ha Campbell I in 2001, and snipe soon began to recolonise the main island from Jacquemart I 1 km offshore. Twelve adults and 5 chicks were caught on Campbell I in Jan 2006, and 1 nest was found. Genetic analysis of blood samples, and measurements and plumage descriptions from these birds revealed that they were best regarded as a subspecies of Coenocorypha aucklandica, a species here recognised as confined to the subantarctic Auckland, Antipodes and Campbell Is, and specifically distinct from the 2 other extant Coenocorypha snipes (Snares I snipe C. huegeli and Chatham I snipe C. pusilla).