Abstract: The current Buller’s albatross taxa (Thalassarche bulleri bulleri [southern] and T. b. platei [northern]) engage in transpacific migrations from breeding sites on New Zealand offshore islands to non-breeding areas in the south-eastern Pacific Ocean. Both taxa are identifiable from a combination of plumage colour features in the head and bill that are easy to detect at short distance (<15 m). There is also breeding allopatry between the taxa, with the onset of breeding 2.5 months earlier in the ‘northern taxon’. In this study, close-range sightings and captures of lured Buller ́s albatross individuals off southern Perú were carried out during two pelagic trips in May–July 2021 onboard a small- scale longline fishery wooden boat (12 m long), during their normal operations when targeting sharks. We report on the presence of 41 Buller ́s albatross, of which 40 were recognized as ‘northern taxon’ and one as ‘southern taxon’. The great majority of the ‘northern taxon’ were adults (92.5%), with the remaining identified as sub-adults (7.5%). Birds were sighted between 126 and 223 km offshore west-south-west from the port of Ilo, Perú (17°38.64 ́S, 71°20.77 ́W). Birds sighted were preferentially in oceanic areas above the abyssal plain (68% of sightings), with a mean depth of 4,537 m, demonstrating that the ‘northern taxon’ is a truly oceanic species. No birds were observed by us over the continental shelf. Discrimination of ‘northern taxon’ from ‘southern taxon’ is possible from a combination of the plumage colour features in the head and bill. However, identification and comparison of photographs for both taxa taken at sea can be problematic, due to varying light conditions, unless the birds can be drawn close to the photographer using attractants, such as offal discards.
Abstract: We report Records Appraisal Committee (RAC) decisions regarding Unusual Bird Reports received between 1 January 2021 and 31 December 2022. Among the 160 submissions accepted by the RAC were the first New Zealand records of black tern (Chlidonias niger), black-naped tern (Sterna sumatrana), and Matsudaira’s storm petrel (Hydrobates matsudairae). We also report the second accepted sightings of northern pintail (Anas acuta) and bridled tern (Onychoprion anaethetus), the third accepted sightings of long-toed stint (Calidris subminuta) and grey-backed tern (Onychoprion lunatus), and the third to fifth accepted records of Adelie penguin (Pygoscelis adeliae). Other notable records included the first record of long-tailed cuckoo (Eudynamys taitensis) from Campbell Island and of sooty tern (Onychoprion fuscatus) from the Chatham Islands.
Abstract: Wing areas and wing loadings of New Zealand land birds are poorly documented in the literature. I therefore report measured wing areas of 84 individual birds belonging to 27 species, with calculated wing loadings. Plotting the data graphically allows some ecological inferences. Heavier New Zealand land birds achieve greater wing loadings than lighter species, as is the case for birds generally. For flying birds, small passerines had the lowest wing loadings (0.12 g/cm2 for the New Zealand fantail) and heavier non-passerines the highest wing loadings (0.88 g/cm2 for the pukeko). I expected non-migratory, forest-dwelling, endemic song-birds with weak dispersal abilities to have very high wing loadings but this was not the case. Instead, native and introduced song-birds of similar size tended to have fairly similar wing loadings. Wing loading was slightly elevated in the North Island saddleback and North Island kokako but the whitehead was normal. The tui, a vigorous flier, had a much lower wing loading than expected for its mass. Data for three flightless species suggest that while high wing loading is an important correlate of flightlessness, it is not the only factor.
Abstract: Hutton’s shearwater (Puffinus huttoni) is a burrowing petrel endemic to the alpine zone of the Seaward Kaikōura Ranges, New Zealand. In November 2019, we accessed an understudied breeding colony at Shearwater Stream in the Puhi Peaks Nature Reserve for the first time since a Mw 7.8 earthquake struck the region in 2016. We measured population parameters and carried out a geomorphological assessment. We estimate that the Shearwater Stream colony supports approximately 3,000 breeding pairs. Ground deformation attributed to the 2016 earthquake did not explain the discrepancy between this estimate and the commonly cited (pre-quake) population estimate of ~8,000 pairs. We highlight the limitations of extrapolated population parameters and of using vegetation cover as a coarse proxy for colony area. We discuss how low burrow occupancy and long-term reductions in the availability of suitable habitat indicate a population at risk of decline. We highlight how stable long-term data for burrow density and breeding success may not be reliable indicators of population health at Shearwater Stream.