We analysed 17 years (2009–2025) of quarterly volunteer 5-minute bird counts (5MBCs) at 20 fixed sites within Brook Waimārama Sanctuary (690 ha), the only mainland mature beech forest enclosed by a predator-proof fence. The dataset documents bird community change following pest eradication in 2017, based on over 6,000 counts by 15 volunteers. Generalised additive models estimated trends for 18 species while adjusting for observer, site, season, weather, and time of day. Endemic species increased markedly relative to the pre-eradication baseline: bellbird (Anthornis melanura) 2.3×, tūī (Prosthemadera novaeseelandiae) 3.0×, South Island robin (Petroica australis) 17.2×, tomtit (Petroica macrocephala) 17.6×. Concurrent wasp (Vespula spp.) control may have contributed to honeyeater recovery. Grey warbler (Gerygone igata), silvereye (Zosterops lateralis), and introduced species declined, while the total number of species per count changed little, indicating community reshuffling rather than net change. Translocated orange-fronted parakeets (Cyanoramphus malherbi) increased steadily following release. Observer differences were among the largest sources of variation. We recommend design features for volunteer 5MBC programmes that would yield robust trend estimates to inform conservation management.
Collections of over 300 small bones and nearly 450 moa eggshell fragments from two Late Holocene eroding sand-dune sites at Herbertville, southern Hawke's Bay, give a snapshot of the pre-human avifauna of the North Island's south-eastern coastline. The remains represent at least 74 individual terrestrial vertebrates of 39 species, half the species being now extinct at Herbertville. In the absence of diagnostic moa bones, analysis of the thicknesses of moa eggshell fragments suggests that three species of moa were present. Identified bones represented 21 species of land birds (a kiwi, two ducks, a quail, a pigeon, five rails, three raptorial birds, four parrots and four song-birds) and 13 species of marine and coastal birds (two waders, two gulls or terns, a penguin, six petrels, and two shags). The commonest bird (by "minimum number of individuals") was weka (Gallirallus australis), followed by little penguin (Eudyptula minor), kaka (Nestor meridionalis), and New Zealand raven (Corvus moriorum). A perinatal New Zealand sea lion femur (Phocarctos hookeri) suggests that this species once bred in the Herbertville sand-dunes. The pre-human avifauna at Herbertville was similar to that described for terrestrial species at Lake Poukawa, 80 km to the north, and for dune forests at Cape Reinga and North Cape.
The Pitcairn Islands support regionally significant seabird assemblages, yet long gaps in monitoring limit understanding of seabird breeding phenology and basic biology. Observations from Oeno Atoll and Henderson Island in September 2025 reveal the importance of eradicating invasive Polynesian rats (Rattus exulans) in 1997 and habitat structure and highlight the potential for asynchronous breeding in many species. Oeno now supports high breeding activity across multiple trophic and nesting guilds, with widespread evidence of recruitment and large colony sizes relative to pre-eradication estimates. Breeding phenology was often protracted or shifted later than previously reported, highlighting substantial temporal variability both within and among islands. In contrast, ground-nesting species on Henderson continue to experience low reproductive success, consistent with ongoing predation pressure from Polynesian rats. Patterns of absence or low detectability in several taxa further emphasise the challenges of short-duration surveys in systems dominated by asynchronous or subannual breeders. Collectively, these findings underscore Oeno’s importance as a recovering seabird stronghold and highlight the need for repeated, seasonally explicit surveys to resolve phenology, population trends, and ecosystem responses to management interventions.
The timing and duration of primary moult in the endemic variable oystercatcher (Haematopus unicolor) are described from 204 records obtained during banding operations and from photographs of birds in flight or wing-stretching. All records were from adults and were collected between 36 degrees and 37 degrees S in northern New Zealand. Records were collected throughout the year, and were analysed using the R package 'moult', which implements the Underhill-Zucchini moult model. Primary moult was not synchronised; the average start date was 04 February, but the 95% confidence limits of start date extended from 12 December to 30 March. The average end date was 08 August (95% confidence limits 15 June to 1 October). Primary moult was therefore very protracted, lasting on average 185 days (6.1 months), and with the whole moult period (first birds to start moult through to the last birds to finish) occupying at least 9.6 months. Birds commonly moulted right through the coldest winter months. This extended moult period is consistent with the fact that adults of this species are non-migratory and highly sedentary. Primary moult also regularly overlapped with breeding. Birds in moult had on average 2.4 primaries active at any time (range = 1-5), with a higher number active while the smaller inner primaries were being re-grown. The gap in the wing caused by primary moult averaged 10% of the total primary feather mass, with a maximum of about 20%. Secondary moult typically began when the primary moult score was in the range 22-30.
Ahuahu / Great Mercury Island is the largest of the Mercury Islands which enables habitat diversity that supports a diverse avifauna. From a combination of quantitative surveys over the past 15 years and qualitative observations over the past 5 years by permanently resident rangers, we list and describe 62 non-vagrant bird species recorded recently on Ahuahu. Reference is made to change over the past 50 years since the last survey in 1975 and also in response to the eradication of introduced cats and rats in 2014. Exotic songbirds have remained relatively unchanged over the past 50 years, dominating open grassland and not responding to mammal eradication. Native forest birds, especially parrots and owls, benefitted from native and pine forest planting and then responded strongly to mammal eradication, particularly in reforested parts of the island. Shore, water and swamp birds also responded strongly to mammal eradication. Sea birds, especially burrowing seabirds, have not responded strongly to mammal eradication, possibly because not enough time has elapsed since eradication or due to factors external to the island. However, burrowing seabirds are abundant on the small islands offshore of Ahuahu where only rats were present, and there appears to have been an increase in adult recruitment of grey-faced petrel immediately following eradication. Eight species are culled as biodiversity and agricultural pests to prevent establishment or reduce numbers. North Island saddleback were successfully reintroduced in 2021 and are now widespread across the southern native and pine forested area of the island, and small rails have also naturally recolonised after mammal eradication. At least 21 bird and 7 reptile species have benefited from cat and rat eradication.
Breeding success can be challenging and labour-intensive to estimate, especially for birds that nest in subterranean burrows such as many smaller Procellariiformes. In burrowing seabirds, breeding success is often assessed using a burrowscope to inspect nests early in incubation and again shortly before fledging. Miniature temperature loggers that measure nest temperature throughout the nesting period may offer an alternative or supplementary method, allowing breeding success to be inferred without a time-sensitive visit just before fledging. Temperature loggers have given reliable estimates of breeding success in birds that nest above ground; however, their efficacy in large, subterranean burrows is uncertain. We tested whether temperature loggers (iButtons) deployed at early incubation stage in the nesting chambers of a burrow-nesting seabird (t & imacr;t & imacr; or sooty shearwater; Ardenna grisea) could be used to assess if a nesting attempt was ultimately successful (i.e., fledged a chick). We monitored the nest chamber temperatures of 96 known-fate nesting attempts, of which 73 (76%) successfully fledged a chick. Using functional data analysis, we show that the probability of correctly assessing a nest attempt's fate at a new site based on its nest chamber temperature data alone was 0.86 (95% CI: 0.79 to 0.93). Temperature loggers may therefore offer an alternative method of assessing nest fate in burrowing seabirds compared to periodic burrowscoping. However, the thermal buffering effects of the burrows suggest that temperature data may not be able to determine fine-scale nesting behaviour such as nest stage transitions.
Tara iti (New Zealand fairy tern, Sternula nereis davisae) are one of Aotearoa New Zealand's most endangered birds, with decades of conservation effort focused on population monitoring, predator control, and habitat protection. This study examined fish species available to and consumed by tara iti through seine-net surveys (2021-2024) at Waip & umacr; and Mangawhai estuaries, supported by direct feeding observations and photography of feeding events. Forty-three fish species were identified across the two sites. While fish community composition differed significantly between estuaries, most variation occurred within sites. Waip & umacr; supported a greater diversity of small-bodied indicator species and juveniles of diadromous or estuarine-dependent taxa, whereas Mangawhai was dominated by juvenile flounder and gurnard. All indicator species represent suitable prey for tara iti and their chicks, highlighting the role of estuaries during the breeding season. However, sampling effort remains biased toward east coast estuaries and summer months, underscoring the need for broader temporal and spatial surveys.
The use of defended feeding territories by New Zealand fairy terns (Sternula nereis davisae) during the breeding season was investigated using 11 years of observations of individually colour-banded birds on Mangawhai Harbour. Breeding birds occupied discrete, spatially fixed feeding territories that were actively defended and used exclusively. Birds without feeding territories did not breed. Territory establishment began about 4 months before laying and was closely integrated with courtship, extending the breeding season without increasing time available for nesting. Males often retained the same feeding territory from year to year, delaying the recruitment of younger males into the breeding population and slowing population growth despite high survival to adulthood. Fierce defence of feeding territories suggests that there is potential competition for food.
Understanding the progression to foraging independence in captive-reared tara iti (New Zealand fairy tern, Sternula nereis davisae) is vital for improving release strategies for this critically endangered taxon. We present the first detailed account of post-fledging foraging milestones for 12 captive-reared juveniles that were released during the 2023-24 and 2024-25 breeding seasons. Observations revealed a predictable sequence of behavioural development: fledging beyond the release pen occurred at an average of 26 days (range 25-28), first successful wild fish capture at 45 days (range 31-62), and juveniles began spending full days away from the release site at an average 51 days (range 41-58), with complete independence, defined as absence for more than five consecutive days and no reliance on supplementary feeding, achieved at approximately 62 days (range 46-80). These findings provide benchmarks for assessing post-release competence and highlight the importance of structured soft-release and supplementary feeding in supporting the transition to independent foraging.
