The hihi (Notiomystis cincta) is a small threatened passerine endemic to New Zealand, for which few methods are known for ageing and sexing wild unbanded individuals. We monitored hihi on Tiritiri Matangi Island over 3 years, studying moult and other sexing and ageing techniques. Juvenile hihi before their first partial moult can be sexed by the white bases of primary coverts on males, which appear brown in females. After juveniles undergo their first partial moult, they appear similar to adults; however juvenile males retain old feathers in their primary coverts, alulae, or sometimes greater coverts or inner primaries, while adults undergo a complete moult. These patterns can be difficult to see in juvenile females, but wear of juvenile tails is much greater than in adults at any given time of year, making ageing of females reliable. Moult in the outer primaries and secondaries in autumn also indicate adult birds. This information should help inform future translocations and attempts to monitor viability of wild populations. Finally, we also comment on alternative definitions for ageing criteria from Melville (2011), based not on suspected birth-dates, but on appearance of plumage in hand.
The foraging ecology of Pitt Island shag (Stictocarbo featherstoni) was studied using GPS archival and Time Depth Recorder devices deployed on incubating birds. Pitt Island shags foraged exclusively during daylight, with a tendency for males to forage mainly during mid-morning and late afternoon, and females in the early morning and around mid-day. Mean foraging distance from colonies was 5.2 km (range 0.4-18.2 km), with males (mean 9.7 km) foraging significantly further than females (3.7 km). Both sexes showed high foraging site fidelity. The depth of most (83%) dives > 5 m deep were similar to the depth of the preceding dive (within 30%), indicating that birds are almost exclusively benthic feeding with the small fluctuations in dive depth likely reflecting changes in seafloor topography. Mean dive depth was 6.6 m, with maximum depth 24.4 m, although 90% of all dives were shallower than 13 m deep. Mean dive duration was 22 s, with a maximum of 69 s, although over 90% of dives were shorter than 40 s. There was a positive relationship between dive duration and dive depth, where deeper dives had longer duration. Mean rest period was 19 s with a weak positive relationship between rest period and duration of the preceding dive. Mean percentage time underwater during each foraging trip was 50.1%, indicating relatively high foraging efficiency. Favoured foraging locations in shallow inshore waters is likely to be a response by birds selectively foraging in sheltered waters protected from oceanic swells. This may be a factor influencing population declines as it intensifies risk to birds as potential threats may be more concentrated in these areas.
Hutton’s shearwater (Puffinus huttoni) currently breeds only in 2 colonies in the Seaward Kaikoura mountains, South Island, New Zealand. Conservation measures now include re-locating young to establish a new low altitude colony. To assess the genetic similarity of birds breeding in the 2 colonies as a basis for decisions on sourcing recruits to the present and potentially other new colonies, we genotyped 9 microsatellite loci, with 3-13 alleles, in 30 birds from the Kowhai River catchment colony and 29 from Shearwater Stream. There was no significant population genetic differentiation between the 2 sampling locations. Our results suggest that there would be little genetic risk to mixing birds from both relict colonies in newly established colonies. Future analyses of the former distributions of Hutton’s shearwater, the fluttering shearwater (P. gavia), and the extinct Scarlett’s shearwater (P. spelaeus) will require an analysis of the levels of genetic similarity between birds from the relict colonies and those of former, widely separated colonies.
Alofi, Futuna and Uvea (also called Wallis), 3 islands situated north of Fiji and Tonga archipelagos, are rarely visited by ornithologists. We present new data on the avifauna obtained during surveys in 2014 and we compare them with previous surveys made in the 1920s, 1980s and 1990s. We recorded the extirpation of 1 species (friendly ground-dove, Alopecoenas stairi) probably related to predation, and the decline of another (lesser shrikebill, Clytorhynchus vitiensis) linked to deforestation. Although the recent arrival of the black rat (Rattus rattus) in Futuna is a potential threat for the blue-crowned lorikeet (Vini australis), no decline is apparent at the present time. In general, most landbirds seemed common despite loss of native habitats and hunting pressure; similarly, the seabird populations and number of species appeared stable, a situation probably linked with the general decrease of harvesting. Finally, 2 breeding species (spotless crake, Zapornia tabuensis, and tropical shearwater, Puffinus bailloni) and 3 vagrants (white-faced heron, Egretta novaehollandiae, masked lapwing, Vanellus miles, and pectoral sandpiper, Calidris melanotos) are added to the list.
The remnant wild populations of the critically endangered orange-fronted kākāriki (Cyanoramphus malherbi) are restricted to 3 North Canterbury valleys where they co-occur with the yellow-crowned kākāriki (C. auriceps). Mixed pairs of Cyanoramphus kākāriki species have been documented throughout the genus, but the extent to which orange-fronted and yellow-crowned kākāriki mate assortatively, particularly when one species outnumbers the other, remains unclear. Here, we investigate the level of assortative mating between orange-fronted and yellow-crowned kākāriki. Based on 355 confirmed nests during 1999-2011, 99% (n = 351) were pure pairings and 1% (n = 4) were mixed pairings. With one exception, the ratio of orange-fronted to yellow-crowned kākāriki encountered during annual surveys ranged between zero and 0.78. These results indicate that the 2 congeners exhibit assortative mating, even when the orange-fronted kākāriki is outnumbered by yellow-crowned kākāriki. The low levels of mixed pairing we observed suggests that the reintroduction of orange-fronted kākāriki should not be precluded to sites where yellow-crowned kākāriki already occur.
Monitoring of wetland birds was undertaken at Lake Ellesmere/Te Waihora during the post-breeding period in February 2006, 2007 & 2008. Census totals were 38,726, 39,917 and 39,175 individual birds over the 3 years, respectively, and 46 wetland bird species were recorded. Nine species had a maximum count exceeding 1000 individuals, including 11,245 grey teal (Anas gracilis), 10,651 black swan (Cygnus atratus), 5776 pied stilt (Himantopus himantopus), 4899 Canada goose (Branta canadensis), 3405 Australasian shoveler (Anas rhynchotis), 1873 banded dotterel (Charadrius bicinctus), 1640 paradise shelduck (Tadorna variegata), 1592 black-billed gull (Larus bulleri) and 1389 mallard/grey duck (A. platyrhynchus/A. superciliosa). Fourteen species were recorded in numbers that met or exceeded the 1% Ramsar international significance criterion: Australasian crested grebe (Podiceps cristatus), black cormorant (Phalacrocorax carbo), white heron (Ardea modesta), black swan, paradise shelduck, grey teal, Australasian shoveler, pied stilt, black stilt (Himantopus novaezelandiae), banded dotterel, wrybill (Anarhynchus frontalis), black-billed gull, black-fronted tern (Childonias albostriatus), and Caspian tern (Hydroprogne caspia). Lake Ellesmere also supported populations of migratory bird species that are uncommon in New Zealand including curlew sandpiper (Calidris ferruginea), sharp-tailed sandpiper (C. acuminata), red-necked stint (C. rufficolis), Pacific golden plover (Pluvailis fulva) and white-winged black tern (Childonias leucopterus). When compared to other coastal wetlands in terms of bird numbers, Lake Ellesmere ranked as the most important site in the Canterbury Region.
We used data from 3 sources to examine the population size and trend of Salvin’s albatrosses (Thalassarche salvini) breeding on Proclamation Island, Bounty Islands, New Zealand. Island-wide counts of breeding birds during incubation resulted in totals that declined 14%, from 3065 in 1997 to 2634 in 2004. A count of breeding albatrosses over part of the island in 2011 indicated a further decline of 13% between 2004 and 2011, and an overall decline of 30% between 1997 and 2011. Additional counts on part of Depot Island indicated a decline of 10% in the numbers of breeding pairs between 2004 and 2011. Daily observations of 70 nests showed that hatching spanned the period from 5 to 21 November 1997, with a median of 15 November, apart from 5 eggs that had not yet hatched by the end of the study period. Based on the banding and recapture of chicks banded in March 1985 annual survival was estimated at 0.926. The scale of the decline estimated in this population has resulted in the conservation status of Salvin’s albatross being upgraded from nationally vulnerable to nationally critical.
Discriminant function analysis (DFA) was used to determine gender and geographic variation in the morphometrics of white-chinned petrels (Procellaria aequinoctialis) measured from fisheries bycatch in New Zealand. Samples were divided into 5 clusters based on capture location. A DFA model was created using adult breeding birds presumed to be from the 2 main locations at the Auckland Islands and Antipodes Islands. Geographic variation in head and bill, skull width, culmen, culmen depth at base, culmen width at base, right and left mid-toe and claw, tail, and right and left wing was found between birds presumed to be from the ‘Auckland’ and ‘Antipodes’ clusters, with ‘Antipodes’ birds being generally larger than ‘Auckland’ birds. Gender variation in head and bill, skull width, culmen, culmen depth at base, culmen width at base, minimum bill depth, right and left mid-toe and claw, right wing, right and left tarsus existed for ‘Auckland’ birds. Gender variation in head and bill, skull width, culmen, culmen depth at base, culmen width at base, minimum bill depth, right and left mid-toe and claw, and tail existed for ‘Antipodes’ birds. Birds in the other 3 clusters were classified as originating from the Auckland Islands or Antipodes Islands. The clustering suggested that birds from the Auckland Islands tended to forage mostly north and west, whereas birds from the Antipodes Islands foraged mostly towards the north. There were large overlaps at Puysegur Point and particularly the Chatham Rise of birds from both breeding locations. This study shows the usefulness of bycatch necropsies, and emphasises the need for further studies in geographic variation and sexual dimorphism at all New Zealand breeding locations.
Weights and measurements of 120 male and 109 female adult and juvenile Australasian shovelers (Anas rhynchotis) were obtained from fresh specimens shot in May, mostly during 1976-1979, at 2 sites in North Island, New Zealand. Mean weights of adult males (634 g) and juvenile males (616 g) were significantly greater than those of adult (608 g) and juvenile (558 g) females. For both sexes, weight/tarsus length2 ratios of juveniles were significantly lower than adults but there was no difference between sexes within each age class. Measurements of bill length and width, tarsus and mid-toe-and-claw, and wing and tail lengths are presented for each sex and age class. All measured characters of juvenile males were significantly longer than juvenile females and adult males were significantly longer than adult females. Within each sex, only wing and tail lengths of adults were significantly longer than juveniles. These findings are typical of other shoveler species.
The field identification of the orange-fronted parakeet (Cyanoramphus malherbi) has been a problem since the species was first described in 1857. Separating this critically endangered species from its more common, but also declining sympatric relative, the yellow-crowned parakeet (C. auriceps), can be difficult, as both species are cryptic and phenotypically similar. To develop criteria for consistent identification, we assessed >2,700 field observations on the orange-fronted parakeet and >10,000 field observations for the yellow-crowned parakeet, where the phenotypes of each bird was compared to the traits of the genetically defined species and verified type specimens. Observations on 117 nests also allowed observations of young from nestling to independence. We concluded that only 2 field marks can be used to reliably separate the 2 species but a clear view of either the frons or rump patch must be seen. The orange-fronted parakeet has an obvious orange frons and rump patch while these areas on the yellow-crowned parakeet are crimson. No other field traits consistently separated the 2 species. Even then, identification can be unreliable when observing juveniles, when light conditions are poor, or if the bird is high in the canopy. We recommend that unless the observer sees a clear and obvious colour in the frons or rump patch, then that bird must remain as unidentified to species.
Over 100 Hutton’s shearwater (Puffinus huttoni) nestlings were translocated to the Te Rae o Atiu colony on the Kaikoura Peninsula in February and March 2013. Passive integrated transponder (PIT) tags were implanted in all translocated nestlings and their movements were monitored using both visual observations and recording devices at nest-box entrances. Once nest-box entrances were unblocked about 5 days after birds were translocated, 29 nestlings were resighted 81 times outside their home nest-boxes either in the open (14 nestlings) and/or other nest-boxes (29 nestlings). From the PIT tag records, 37 birds were observed visiting at least 49 nest-boxes on 109 occasions. The most mobile bird made 15 visits to 12 other nest-boxes over 9 nights; another bird visited 6 boxes in one night; and 1 box had 3 visitors in a single night. Nestlings moved within the colony in the period between 1 and 16 nights before fledging, with an average of 8 nights with movement before fledging. The PIT tag readers also showed that the use of pins outside nest-box entrances to determine movements can be misleading as pins were moved up to 13 nights before the nest-box occupant emerged, the pins being moved either by visitors to the nest-boxes or by nestlings wandering past the entrance.
The South Island kokako (Callaeas cinerea) was officially declared extinct in 2007, with the most recent report accepted by the Ornithological Society of New Zealand’s Rare Birds Committee, being in 1967. However reports of potential observations of South Island kokako continued to appear. We compiled a total of 241 reports between January 1990 and June 2012. These reports were categorised into 6 categories depending on the details provided by observers. The most highly ranked reports required identification of the wattles which are the most distinguishing feature of South Island kokako. The 13 reports from the highest category were submitted to the Bird Threat Ranking panel in June 2012 and, based on this evidence, the species was then reclassified from “extinct” to “data deficient”. The most compelling 11 reports were then submitted to the Ornithological Society of New Zealand’s Records Appraisal Committee (RAC). One report was accepted as a South Island kokako while 2 were deemed to be of North Island kokako. This paper reviews all available reports of the South Island kokako from 1990, the assessment process and a map of the distribution of reports. Our analysis of these reports suggests that the South Island kokako is extant.
The breeding ecology and reproductive traits of brown booby (Sula leucogaster etesiaca) were studied in Gorgona Natural National Park, Colombia. Adult morphometrics, egg dimensions, chick growth and nesting site characteristics, were examined at 3 locations in the park. As with other subspecies, brown boobies in Gorgona exhibit reversed sexual dimorphism. The female booby reaches about 80 cm in length, its wingspan measures up to 150 cm, and they can weigh up to 1,300 g. The male booby reaches about 75 cm in length, its wingspan measures up to 140 cm, and they can weigh up to 1,000 g. First-laid eggs were heavier and bigger than second- or third-laid eggs. Growth of brown booby chicks fit a natural log equation: body mass (g) = 0.8773 ln * days + 3.3895. A variety of nesting aggregations was found, and their relationship with the other marine birds nesting in the area is discussed.
I conducted observations on the diet of the Floreana mockingbird (Mimus trifasciatus) during its breeding season in February and March 2011. The Floreana mockingbird is a critically endangered species restricted to Gardner and Champion Islets off the coast of Floreana Island, in the Galápagos Islands, Ecuador. During 11 days, 172 feeding bouts of adult and nestling mockingbirds were observed. The majority of feeding bouts of adults (31%; 19 feeding bouts) involved the consumption of nectar and pollen of Opuntia megasperma. Another important food item consisted of Lepidopteran caterpillars (27%; 17 feeding bouts). The majority of food items fed to nestlings consisted of Lepidopteran caterpillars (26%; 29 observations), followed by adult spiders (19%; 21 observations). The reintroduction of the species to its historical range on Floreana Island is currently being planned with an emphasis on the control or eradication of invasive cats and rats. To identify key areas for reintroduction, a study on the year-round diet of the species as well as availability and variability of food items is recommended. Nectar and pollen of Opuntia megasperma was an important dietary item for the species during its breeding season. This slow-growing plant species was widespread on the lowlands of Floreana Island but introduced grazers removed Opuntia from most of its range. In the context of the potential reintroduction of this species to Floreana Island, it is important to establish if this high-energy resource is key for breeding, and consideration should be given to a supplementary food program as it has been successfully implemented for bird species elsewhere.
The monitoring of endemic birds during the control of introduced mammalian predators is a common practice at community-based conservation projects in New Zealand. We describe long-term trends of endemic passerines monitored using the presence-absence technique during the control of stoats (Mustela erminea) and brushtail possums (Trichosurus vulpecula) in the Flora Valley, near Nelson, New Zealand. Data collected over an 8 year period by Friends of Flora, a community-based organisation, suggests that bellbirds (Anthornis melanura) significantly increased, while South Island robin (Petroica australis), tomtit (P. macrocephala) and rifleman (Acanthisitta chloris) populations showed little or no change, and grey warblers (Gerygone igata) significantly decreased. All species showed a greater increase during the first 4 years of the survey compared to the second 4 years, which suggests that meso-predator release of rats may have occurred from ~4 years after the start of the surveys. The presence-absence technique is simpler to conduct than the more commonly used 5-minute bird count method, and thus may be better suited for use by the community sector in similar situations.
We present counts of white blood cells of wild and clinically normal red-crowned parakeets (Cyanoramphus novaezelandiae) from 2 island populations in New Zealand. Total white blood cell counts on slides prepared in the field and counts of relative proportion of basophils, eosinophils, heterophils, lymphocytes and monocytes were determined for 33 individuals caught on Little Barrier Island and 48 individuals caught on Raoul Island. Mean haematological parameters were: total white blood cells 6.85 cells x 109/L, lymphocytes 5.0 x109/L (74.0%), monocytes 3.5 x109/L (5.7%), eosinophils 4.6 x109/L (6.4%), basophils 1.9 x 109/L (3.1%), and heterophils 9.9 x109/L (14.7%). Raoul Island parakeets had significantly higher counts of white blood cells, lymphocytes, and heterophils than Little Barrier Island parakeets, possibly reflecting latitudinal differences. Males showed significantly higher counts of white blood cells and lymphocytes than females. White blood cell counts on slides prepared in the field represent an inexpensive and straightforward technique to determine variation in the levels of each cell type and to assess the physiological state of healthy and diseased individuals. This information is useful for veterinary clinicians, wildlife managers, and conservation biologists who increasingly require methods for health assessment, disease diagnosis, and screening for pathogenic microorganisms on species of conservation concern.