Publications Archive

Holdaway, R.N.; Allentoft, M. E. 2022. A basic statistical approach to determining adult sex ratios of moa (Aves: Dinornithiformes) from sample series, with potential regional and depositional biases. Notornis 69: 158-173.

Albatrosses and petrels are among the most endangered seabird species worldwide. They face threats such as plastic ingestion, bycatch in fisheries, invasive predators at breeding sites, light pollution, and climate change. Many seabird species from Aotearoa New Zealand migrate to the eastern Pacific waters during the non-breeding season, following the abundant food availability of the Humboldt current. In this article, we compile observations of Thalassarche and Procellaria petrels in Ecuadorian waters from five information sources such as incidental tourist vessel observations, incidental fishermen observations, beach patrols, seawatching and GLS loggers. We provide strong evidence of the presence of Salvin’s albatross and White-chinned petrel in Ecuador, two species previously considered hypothetical for the country’s official bird list. Additionally, we present photographic evidence of a live Southern Buller’s albatross in Ecuador and document further observations of the black petrel, including its interactions with local fisheries. These records emphasize the importance of enhancing monitoring efforts to gain a deeper understanding of the ecology and conservation of Ecuador’s seabirds. They also highlight the necessity and advantages of collaboration between New Zealand and Ecuador concerning highly mobile bird species.

Abstract: Coastal and nearshore habitats are important to all seabird species. Understanding the distribution of seabirds in these environments can aid in their conservation. Despite the importance of coastal habitat, data collection for seabird species at sea is often difficult and resource intensive. Here, we take advantage of an established marine mammal surveying programme to collect distribution data for seabird species encountered in nearshore habitat. We surveyed seabird communities over 76 days in four locations along the southeast coast of New Zealand’s South Island; Dunedin, Moeraki, Timaru, and Banks Peninsula. We present observations of seabird species presence in these locations, as well as, a brief assessment of the counting techniques used during the study. In addition, we summarise the seabird numbers in relation to the marine mammal surveys (i.e. the presence and absence of dolphins). We aim to show the value of opportunistic data collection, while contributing to baseline species distribution knowledge.

Kawau pāteketeke | New Zealand king shag (Leucocarbo carunculatus) nest occupancy, breeding, and offspring survival was studied for the first time at four colonies in 2018 and 2019, by analysing field camera still images. Nesting territories were retained year-round. Nest-building was underway by Mar and observed through much of the year. Successful pairs with stable nests were elevated and central to nest areas. Inter-colony asynchronous first clutches occurred over six months, with laying spanning 5–10+ weeks at single colonies (2019). Clutches of 2–3 eggs took ≤13 days to complete. Incubation commenced with first eggs; asynchronous hatching was 28–32 days later with brood reduction at early nestling stage and occasional replacement clutches observed. Chicks were unattended at 3–4 weeks, showing strong creche behaviour thereafter, and were fully feathered at 65 days, fledging soon after. Breeding outcome was most influenced by height above sea-level (waves), exposure (weather), and boat/landing disturbance. Most young disappeared from images at 4.5–5 months, their fate—dispersed or perished—unknown. Some resided at the colony into/ beyond the subsequent breeding season, sometimes interacting with presumed parents. Any predation (by gulls) was seen as opportunistic during disturbances, or of eggs not in nests.

Egg floatation is a technique which can be used to estimate egg age and hatching dates of New Zealand shorebird eggs. It can be used to improve the accuracy of nest survival models, help identify nest outcomes, assist with chick survival monitoring and to prioritise the capture of incubating birds. We used egg floatation to estimate the age and hatching dates of South Island pied oystercatcher (Haematopus finschi) (SIPO) eggs. We developed regression equations to estimate the age of SIPO eggs by modelling egg angle and egg float height against egg age using a sample of eggs with known hatch dates. For early incubation eggs, we used linear regression to model the relationship between egg age and egg angle only, whereas for late incubation eggs we used multiple regression to model the relationship between egg age and both egg angle and egg float height data. These equations allowed 90% of SIPO eggs to be aged to within five days of their actual age. We recommend that species-specific regression equations describing the relationship between egg float characteristics and egg age be developed for other New Zealand shorebird species, to aid future research, monitoring and conservation management actions on these species.

Abstract: Observations were made of the Nationally Vulnerable Hutton’s shearwater (Puffinus huttoni) breeding at Te Rae o Atiu, Kaikōura Peninsula (42.429°S, 173.703°E), New Zealand, a new colony established by translocations where birds breed in nestboxes. Over 12 seasons there were 245 eggs laid, including seven instances of two eggs laid as separate clutches in one nestbox during the same season. Nestbox inspections, usually undertaken weekly, provided evidence of egg laying date. Bird attendance at the nestboxes was also obtained from implanted passive integrated transponders that triggered a reader and datalogger. There is evidence for birds re-laying an egg after the first egg failed for three separate events, and a fourth was a possibility. In three other events, it appears more likely that two different birds laid the eggs, two as female-female pairings or simply egg dumping by an unpaired female; the third event was inconclusive. Only one of the 14 eggs from two-egg nests hatched, and the chick fledged successfully, about 10 days later than any other chick recorded at this colony. This fledging date was similar to the last date for fallout birds from the natural, mountain colonies, and suggests that re-laying may be a natural consequence of early egg failures in this species.

Since the publication of the fifth edition of the Checklist of the Birds of New Zealand in 2022, 3 new vagrant species (2 terns and a storm petrel) have been accepted as occurring in New Zealand as at 31 December 2023, and 11 species that became extinct more than c. 1 million years ago have been described. These comprised 3 waterfowl, 1 owlet-nightjar, 1 tropicbird, 3 penguins, 1 albatross, 1 petrel, and a ‘false-colie’ (the latter is considered unrelated to any known group of birds). These 11 new fossil species were found in deposits of the following epochs: Paleocene (3), Miocene (6), and Pliocene (2). The richest areas for discovering new species were Miocene lacustrine deposits of the St Bathans region of Central Otago (5 species), and Paleocene marine deposits from the eastern South Island (3 species). Two Pliocene seabirds were from marine sediments in south Taranaki, and a Miocene albatross was found in a limestone quarry in South Canterbury. Recent publications potentially affecting the taxonomy, nomenclature, classification and arrangement of New Zealand birds are assessed, and recommendations are made that affect 56 taxa. This includes splitting Tibetan sand plover Anarhynchus atrifrons from Siberian sand plover A. mongolus, and Pyramid prion Pachyptila pyramidalis from fulmar prion P. crassirostris, thereby adding a further two species to the New Zealand bird list. The total number of bird species, including fossil species, now accepted from the New Zealand region is 502.

The wrybill | ngutu pare (Anarhynchus frontalis) is a small plover endemic to New Zealand with a unique laterally curved bill. Apart from moult, much of its biology is well understood: adults breed from late August to January on the braided river systems in Canterbury and inland Otago on New Zealand’s South Island. From midsummer, late December and January, they migrate north to non-breeding areas in the northern part of the North Island, especially to the large tidal bays, east and west of Auckland, where they undergo primary moult from January to April. The Underhill- Zucchini moult model was used to estimate the mean start and completion dates of primary moult, which were 20 January and 3 April respectively. Adults thus commence primary moult soon after arrival on non-breeding grounds but complete moult around four months before southward migration to their breeding areas in August. They appear to avoid primary moult during winter. Second-year birds start primary moult in December, one month earlier than the adults, but finish at approximately the same time. Primary moult of the wrybill is compared with closely related species, and with other waders that breed on the South Island and migrate to North Island for the non-breeding season.