The Auckland Islands are the largest island group in the New Zealand subantarctic region, and have the most diverse avifauna, including eight endemic taxa. We present the first comprehensive review of the avifauna of the Auckland Islands, based on a database of 23,028 unique bird records made between 1807 and 2019. At least 45 species breed (or bred) on the islands, with a further 77 species recorded as visiting the group as migrants, vagrants, or failed colonisers. Information on the occurrence of each species on the different islands in the group is presented, along with population estimates, a summary of breeding chronology and other reproductive parameters, and diet where known. The frequency at which 33 bird species were encountered during visits to the seven largest islands is compared graphically to facilitate comparison of each island’s bird fauna in relation to habitat differences and the history of introduced mammals. Disappointment Island (284 ha) is the least modified island in the group. However, it lacks forest, and so has a very restricted land bird fauna, lacking ten species that breed on other islands in the group. Auckland Island (45,889 ha) is the only major island in the group where introduced mammals are still present. As a result, it also has a depauperate bird fauna, with at least 11 species completely absent and a further seven species reported at lower frequencies than on the next largest islands (Adams and Enderby Islands).
Banded dotterels (tūturiwhatu, Charadrius bicinctus bicinctus) are small plovers inhabiting New Zealand’s braided rivers, estuaries, seashores, and open country. They are considered Nationally Vulnerable under national threat listing criteria, but with uncertainty around the trend estimation. We collated and reviewed counts of banded dotterels on their braided river breeding grounds from throughout the country, 1962–2017, to describe their distribution, assess population trends, estimate rates of population change, and assess the appropriateness of the threat status given to this species. We also used nationwide winter count data for banded dotterels from 1984 to 2018 as an independent measure to compare trends. Banded dotterel counts were recorded for 119 braided and shingle river reaches, mostly in the South Island (87%) with far fewer rivers in the North Island (13%). The sum of banded dotterel counts was 12,730 birds when tallying the most recent counts/river. Although they were most widespread in the South Island, particularly Canterbury, the majority (>50%) of dotterels counted on the most recent surveys were from just 10 (8%) rivers with the largest single concentrations on three Hawkes Bay rivers. Counts suitable for long-term trend analysis were only available for South Island sites. Widespread declines in banded dotterel count indices were recorded. The weighted mean annual rate of change across 33 South Island rivers was -3.7% p.a. (per annum), which equates to a 52.3% decline over 20 years (~3 generations). We also detected a negative trend in dotterel numbers based on national winter count data, but of a smaller magnitude (-1.4% p.a., equating to a 25% decline over 20 years). However, trends in Australia, where c. 60% of banded dotterels over-winter, are unknown. In contrast, a significant population increase was measured on the Hakatere Reach of the South Ashburton River, which has intensive, sustained predator control, and several predator trapping initiatives on other braided rivers and coastal areas indicate declines can be reversed with management if applied at an extensive landscape scale. Banded dotterels are subject to a wide range of threats including very high levels of predation by invasive predators, human disturbance on breeding grounds, and habitat loss and degradation. Using the precautionary principle, the rates of decline on South Island braided rivers confirm the classification of Nationally Vulnerable using the NZ Threat Classification system. However, results suggest that the IUCN threat status for banded dotterel should be reclassified from Least Concern to Endangered.
For 11 breeding seasons, a colony of little penguins (Eudyptula minor) was monitored at South Bay, Kaikōura. The 106 breeding attempts from 86 pairings consisted of 68 single clutches, eight attempts made up four replacement clutches (an unsuccessful original clutch followed by a second clutch by a pair in one season), 26 attempts consisting of 13 double broods (a successful original clutch followed by a second clutch by a pair in one season), and one complex triple brood (three successful attempts by a penguin in one season, the triple brood, plus another successful attempt by its first mate after separation). The earliest laying date was 18 April for multiple brooders and 12 August for single clutch pairs. Single clutch pairs raised a mean of 1.42 fledglings/clutch. Four pairs with first clutch failures laid replacement clutches; one was successful. Seven of the 13 pairs of double brooders successfully raised the second clutch; the productivity of the 13 pairs was 2.69 fledglings/pair. The first record of a successful triple brood by little penguins was complex in that the female separated from her mate after the first brood chicks fledged, and then completed her second and third broods with a different male. Her original mate also produced a further brood with another female to complete his double brood. These four clutches laid eight eggs of which seven hatched and six chicks fledged. This may also be the first reported multiple brood with a change of mate after a successful first brood. On a colony-wide basis productivity per season was 2.36 eggs/pair, 1.80 chicks/pair, and 1.66 fledglings/pair. Previous research indicated Kaikōura birds belonged to the New Zealand Only (NZO) clade of little penguins. As double brooding and rafting are traits of the Australia and south east New Zealand (ASENZ) clade only, this classification is now questionable suggesting a mix of both clades and/or hybrids.
Black-fronted terns (Chlidonias albostriatus) are globally endangered and are one of six endemic bird species that rely on New Zealand’s braided river ecosystems for breeding. Like other marsh tern species, black-fronted terns are predicted to have low breeding-site fidelity due to the instability of their breeding habitat, small colony sizes and high predation rates. We used breeding colony location data collected from nine South Island rivers for 3–12 years (2004–2015) to investigate the breeding-site fidelity in black-fronted terns. The distribution of breeding colony locations from seven of the nine rivers analysed were not significantly different to a simulated random distribution. The tendency of black-fronted terns to form breeding colonies near past breeding site compared to new sites was only significant for two of the nine rivers analysed. Overall, there was low breeding-site fidelity in black-fronted tern colonies from year to year across the rivers analysed.
Maungatautari is a 3,240 ha pest-fenced ecosanctuary free of virtually all mammalian predators in Waikato, New Zealand. We used triennial 5-minute counts within the ecosanctuary and biennial surveys of residents up to 20 km from the perimeter pest fence to measure spillover of tūī from Maungatautari into the surrounding area over a 9-year period (2006–2014) following pest eradication. Following pest eradication in the ecosanctuary, tūī relative abundance increased there and in the surrounding largely unmanaged area. The mean number of tūī per 5-minute count within the ecosanctuary was 2.23 (se = 0.163) in 2005 and increased following predator eradication in 2006 to 3.33 (se = 0.206) in 2008, 3.76 (se = 0.193) in 2011, and 2.68 (se = 0.279) in 2014. The mean maximum number of tūī at one time observed by residents in the largely unmanaged area increased from 4.4 (max = 47, n = 320) in 2006 to 15.6 (max = 300, n = 138) in 2014. Tūī numbers in both the ecosanctuary and the surrounding area were positively correlated with time since pest eradication. In the largely unmanaged area surrounding Maungatautari, tūī numbers were also positively correlated with provision of artificial food, and negatively correlated with distance from the ecosanctuary. Wind was negatively correlated with the number of tūī recorded in 5-minute counts at Maungatautari. Our findings show that pest-free ecosanctuaries can facilitate increased abundance of volant birds in surrounding landscapes if habitat is available.
We report Records Appraisal Committee (RAC) decisions regarding Unusual Bird Reports received between 1 January 2017 and 31 December 2018. Among the 160 submissions accepted by the RAC were the first New Zealand records of Macquarie Island shag (Leucocarbo purpurascens) and Cox’s sandpiper (Calidris x paramelanotus), and the first accepted at-sea sightings of blue petrel (Halobaena caerulea), Salvin’s prion (Pachyptila salvini), Antarctic prion (P. desolata), and thin-billed prion (P. belcheri) from New Zealand coastal waters. We also report the second accepted breeding record (and first successful breeding) for glossy ibis (Plegadis falcinellus), and the second accepted records of red-footed booby (Sula sula) and laughing gull (Leucophaeus atricilla). Other notable records included the first record of nankeen kestrel (Falco cenchroides) from Campbell Island, and at least 5 northern shovelers (Anas clypeata) simultaneously present in June 2018.
Rotuma, Fiji, is a small and isolated island in the Central Pacific, rarely visited by ornithologists. We present here our own observations on the avifauna, obtained in 1991 and in 2018, completed by previous records obtained since the 19th Century. The main changes on the species composition concern the extirpation of the white-throated pigeon and the settlement of the reef heron. The status of the four endemic landbirds (one species and three subspecies) is good, especially that of the Rotuma myzomela. However, the recent arrival of the common myna (2017–2018) represents a potential threat. We also observed that the Pacific sheath-tailed bat, which was abundant 30 years ago, has probably been extirpated from the island.
Little penguins (Eudyptula minor) readily breed and moult in nest boxes. The selective placement of nest boxes can enhance their use, improve breeding success and increase recruitment. I examined nest parameters for 171 nest boxes at Pilots Beach, southern New Zealand, in relation to their use for breeding and for moulting in the 2016 breeding season. Linear models to assess the relative importance of nest box parameters produced definitive results where a higher likelihood of use was interpreted to indicate a preference. The only preference for breeding or moulting was for shaded boxes that were free of vegetation at ground level. These trends were supported by comparisons of proportions of boxes used for breeding and moulting that indicated shaded boxes surrounded by bare ground were preferred to unshaded boxes surrounded by introduced grasses. Proportions also indicated that boxes on flat ground with a flat entrance were preferred to boxes on sloped ground or a sloped entrance for breeding and moulting. About half of the boxes between 61 and 90 m distance to the landing were used for breeding and moulting. Females nesting in shaded boxes had a higher breeding success than those in unshaded boxes but their chick masses were similar. To optimise nest box use by little penguins and encourage recruitment, nest boxes ideally should be placed under bushes or artificial structures on open ground up to 90 m from the landing.