Four New Zealand pipit nesting attempts were monitored in an urban wasteland field in Onerahi, Whangarei.A female laid two clutches in dense kikuyu (Pennisetum clandestinum) in October and December 2015 and fledged young from both clutches. Pipits were then absent from the site from February until late August 2016. The male reappeared and used the exact same home range, with a new female. This female laid two nests in the more open low gorse (Ulex europaeus) and aristea (Aristea ecklonii) cover in September and October 2016 but both nests were depredated at 3–5 and seven days after hatching, respectively. All three chicks, the female, and possibly the male were killed during the latter predation event. There were differences in adult behaviour throughout the breeding cycle. The female constructed the nest and undertook all the incubation. During the incubation period the male was only present at the nest site in the early morning and did not roost at the site each evening. The pair was present throughout the day after the chicks hatched. Pipits used more frequent calling rates when there was a perceived threat, and when that threat was near a nest.
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.
A national census of breeding black-billed gulls (Larus bulleri) conducted across New Zealand in 1995‒98 estimated 48,000 nests, however the methodology used was unclear. In 2013, the New Zealand threat status for the endemic black-billed gulls was changed to Nationally Critical, based on estimates of recruitment failure causing population decline. To inform future threat classification, the breeding population was re-estimated using aerial surveys to locate, photograph, and count breeding black-billed gulls across New Zealand in 2014‒2016. Large spatial gaps in nest count data during 2014/15 and 2015/16 did not allow for annual variability to be taken into account across the 3 seasons, but the 2016/17 survey successfully covered the entire country. Ground counts of nests were conducted at 16 colonies to determine a correction factor of 0.90 to apply to aerial photograph counts of apparently occupied nests. A total of 60,256 nests were found, with 33,703 nests in Southland and 20,675 nests in Canterbury. The North Island was surveyed on the ground and had 992 nests. Historical survey methods were reviewed, highlighting the inaccuracies of using nest densities or applying factors of gulls/nest to total bird counts based on photographs, as well as only counting individual birds on aerial photographs. Historical data likely overestimated numbers of breeding birds, and the inconsistencies of previous surveys make trend analyses difficult. Key recommendations for future counts include: (i) carrying out ground surveys before flights to determine the breeding stage of birds and hence the optimal time to fly; (ii) taking high resolution and zoomed in photos; (iii) carrying out ground nest counts immediately after flights to determine a correction factor; and (iv) using the same observers for all counts to maintain consistency.
Observations of activities of Hutton’s shearwaters at a natural colony in the Kōwhai River and a new colony at Te Rae o Atiu, Kaikōura Peninsula established by translocations were made during the 2014-15 and 2015-16 seasons. Weights and wing lengths of chicks at the 2 colonies taken at comparable times were similar, as were the dates of first emergence and fledging. Thus, adults flying an additional 20 km each way and climbing over 1200 m had no noticeable effect on chick growth at the mountain colony compared to the sea-level colony. Pre-fledging chicks visited other burrows as did adults at both sites, especially at Te Rae o Atiu, where a greater amount of data showed they visited other burrows throughout the season. While some adults stopped visits before fledging, others were still present after chicks had gone. Seven birds that were translocated from the Kōwhai River colony as chicks to Te Rae o Atiu in 2012 and 2013 were recorded at the Kōwhai colony and 2 of these had previously spent 1 night at Te Rae o Atiu; 28 more from the same cohorts were active at Te Rae o Atiu.
Following an initial aerial census of breeding New Zealand king shags (Leucocarbo carunculatus) in 2015, 2 further aerial censuses were carried out in 2016 and 1 census in 2017. In 2016, birds were photographed on 2 separate dates using a hand-held camera from inside a fixed wing aircraft. In 2017 the birds were photographed from a fixed-wing plane equipped with an automated camera system mounted below the aircraft. Photographs were independently assessed by 3 observers in 2016 and 2 observers in 2017. Nesting pairs were identified and the figures were averaged per colony for a final estimate of the number of active nests. The first census for 2016 was completed on 6 June and 89 active nests were estimated, compared with 117 nests counted on 1 July. For some colonies, breeding appeared to have just started in June 2016, so an underestimate of active breeders during the first aerial census was the probable cause. The 2017 aerial census was completed on 21 June and we identified 153 active nests. All follow up aerial surveys in 2016 and 2017 were well below the 187 active nests recorded in the 2015 study but within the historic variation. The exception to this trend is Trio Island, where no breeding colony was observed in 2017, the first time this has been recorded at this site.
The tendency of various species, including many Procellariiformes, to breed in sub-terrestrial burrows, complicates breeding biology studies. Artificial nest boxes facilitate detailed data collection, but may alter the buffering capacity of natural burrows, especially when these nests are exposed to direct sunlight (e.g., in non-forested habitats). We tested the buffering capacity of artificial nest boxes, equipped with additional insulating features, ex-situ in a non-forested sand dune in New Zealand. Specifically, we compared daily temperature (°C) and relative humidity (%) means, minima, and maxima between artificial nest boxes, Procellariiform burrow replicas, and ambient conditions sourced further inland using linear mixed effects models (LMMs), followed by post-hoc tests. Differences between artificial nest boxes and replicas were non-significant (P > 0.05). Our results thus showed that the applied insulating features were sufficient to retain the buffering capacities expected in natural burrows, even in exposed habitats such as sand dunes. Hence, we encourage the use of insulated artificial nest boxes in breeding biology studies targeting burrowing Procellariiformes (and other sub-terrestrially breeding species) in non-forested areas.
To investigate factors that might influence calling rates of morepork (ruru, Ninox n. novaeseelandiae), Song Meter SM2+ acoustic recorders were deployed for 12 months recording every night at Hodges Bush (a remnant forest) and Trounson Kauri Park (TKP) in Northland, New Zealand. Three call types were recorded: the classic ‘morepork’ hoot, the ‘wheel’ and ‘wok’. There was no strong seasonal variation in ‘morepork’ hoots from Hodges Bush, although there were fewer hoots from February to March. At TKP, the number of hoots declined from June to August, but the number of ‘wheel’ and ‘wok’ calls remained constant. At dusk, ‘Morepork’ hoots gradually increased until they were at their greatest frequency 3 hours after sunset at both sites. Thereafter, the number of calls reduced through the night at TKP, but remain constant at Hodges Bush until a second peak 2 hours before dawn, after which numbers drop off markedly. The other two call types were constant throughout the night at both localities, but with a pre-dawn peak at Hodges Bush. There was no significant correlation between calls and moon phase at either site. We suggest that it is possible to use vocal activity as a means of monitoring morepork population changes, but more studies are needed to determine variations between sites and different population densities.
We describe the creation of a standardised set of data from the two national atlases of bird distribution compiled by the Ornithological Society of New Zealand. The data provide estimates of local occupancy probability for each of 64 taxa of native land birds, in each of 2,155 grid squares covering the North, South, and Stewart islands, in two measurement periods (September 1969 – December 1979, and December 1999 – November 2004). Because these local occupancy estimates were derived on an identical basis for each bird taxon and each time period, they enable unbiased comparisons between time periods and among species. Links to permanent data repositories of the original and standardised data are provided.