Historical records of the Chatham Island oystercatcher (Haematopus chathamensis) suggested a sparse and small population. In 1970, there may have been as few as 52 birds, but this apparently increased to 112 in 1987 and 144 in 1998. Intensive predator control and nest and habitat management has since boosted productivity and recruitment of oystercatchers along the northern Chatham Island (Rekohu) coastline and resulted in a rapid increase in total numbers; by 2004 there were 316
Large albatrosses, subsequently identified as Antipodean wandering albatrosses (Diomedea antipodensis), began prospecting for nest sites inland from the south-western coast of Chatham Island about 1998. The 1st egg was laid about the end of Mar 2003. What is presumed to be the same female laid an egg nearby in Feb 2004 and 2005. Although the 2004 egg hatched, each of these 3 breeding attempts failed. A subadult male Antipodean wandering albatross was found in Waipaua Scenic Reserve on Pitt Island in May 2002, and what may have been the same bird was ashore at the same site in Jan 2004. An egg was found at this site in Apr 2004 and the resulting chick fledged in Jan 2005. What is presumed to have been a different pair was found with an egg on Mount Hakepa, Pitt I, in early Jan 2006; their egg hatched in Apr 2006, and the chick fledged about 7 Jan 2007. What is presumed to be the same pair also nested successfully at the Mount Hakepa site in 2008/2009, with the chick fledging on 6 Jan 2009. These 6 breeding attempts (3 successful) by perhaps 3 different pairs at widely spaced sites on the Chatham Islands are the 1st records of Antipodean wandering albatrosses breeding away from the Antipodes Is and Campbell I.
Introduced mallards (Anas platyrhynchos) occur on many islands of the South Pacific, where they hybridise with the resident grey duck (A. superciliosa). In October 2007, we conducted systematic surveys of Lord Howe Island to estimate the abundance and distribution of grey ducks, mallards, and their hybrids. Hybrids were common in areas of high public use, particularly where there was mown or grazed grass. Phenotypic characteristics suggest that mallards are now dominant and have supplanted the native grey duck, with 81% of birds classified as mallard or mallard-like hybrids, 17% as intermediate hybrids and only 2% as grey duck-like hybrids. No pure grey duck were observed. These hybrids pose direct and indirect economic, social and environmental impacts to Lord Howe Island. A management program to remove mallards using trapping, shooting and opportunistic capture by hand was conducted in October 2007. Standardised indices of duck abundance before and after management indicates that the total population was reduced by 71.7%. Eradication of mallard and hybrids from Lord Howe Island is considered achievable with a program of education, monitoring, and continued control to prevent re-establishment.
A small black-and-white storm petrel seen off Whitianga, New Zealand, in Jan 2003 was tentatively identified as a New Zealand storm petrel (Pealeornis maoriana). A further sighting in the Hauraki Gulf in Nov 2003 of multiple birds identified as New Zealand storm petrels led to the realisation that the species was both extant and apparently locally common. Prior to these sightings this enigmatic seabird was known only from 3 specimens collected in the 1800s, and unreported since. This paper reviews these 2 sightings that constitute the rediscovery of an
The nesting of variable oystercatchers (Haematopus unicolor) on the Kaikoura Peninsula was studied at 6 sites over 8 years. Only in 1 year were birds known to have laid eggs at all 6 sites and only at 2 sites was nesting observed every year. Loss of nests often resulted in re-nesting and at 1 site birds made 4 attempts in 1 season. Over the 8 years, 117 eggs were found in 53 nesting attempts between mid-Oct and late Jan. The average size of 114 eggs was 58.2 x 40.6 mm. Thirty of 53 nesting attempts were completed and averaged 2.4 eggs/clutch (range 1
Thirty-four species of birds are recorded from the isolated Pacific island of Nauru. Six are treated as hypothetical pending corroboration; 3 others are introductions. Eighteen of the 25 indigenous species are non-breeding visitors (mainly migrating seabirds and shorebirds). The 7 confirmed or probable resident breeders include only 2 land birds, the Micronesian pigeon (Ducula oceanica) and the endemic Nauru reed-warbler (Acrocephalus rehsei). The Australian pelican (Pelecanus conspicillatus) and white-winged tern (Chlidonias leucopterus) are reported as first records for Nauru. Hunting pressure and habitat degradation have contributed to reduced numbers of the Micronesian pigeon and the once abundant black noddy (Anous minutus), but the Nauru reed-warbler occurs commonly in degraded and modified habitats. Second-stage mining to recover phosphate deposits will likely reduce available habitat further for all resident breeding species, although land restoration is also planned. Bird band recoveries indicate that many seabirds, especially black noddies, reach Nauru thousands of kilometres from where they were fledged, but to what extent they are recruited into the local breeding population is unknown.
During 1971-75 and 1991-95, surveys of Caspian tern (Sterna caspia) colonies throughout New Zealand were carried out. The breeding population in 1971-75 was 1266 pairs, in 16 colonies, predominately in the northern North Is. In 1991-95, there were 1190 breeding pairs found in 17 mainly northern colonies, suggesting the population had been relatively stable over the 20-year period. As census methodology may under-record the breeding of isolated pairs, we included an estimate of the number of isolated pairs to give a total national population of 1300-1400 breeding pairs. This is less than 3% of the global population. Colony size and location showed some change between survey periods; 6 colonies disappeared and 8 new colonies were formed. Addition surveys in 2011-2015 are recommended to compare recent population trends.