Sexual differences in vocalisations of the Vanuatu petrel (Pterodroma occulta) are described. Qualitative differences in burrow calls could be used to sex adults with 63-100% accuracy in listening experiments. Males sounded “clear” and females sounded “hoarse”. Higher accuracy is possible with the aid of spectrograms. Playback experiments demonstrated a male-bias in responses of incubating Vanuatu petrels to “war-whooping” and flight calls. Acoustic methods have practical and ethical advantages over handling breeding petrels and further studies of the vocal behaviour of gadfly-petrels are encouraged.
Edgar Stead (1881-1949) documented avian diversity on the islands around Stewart I during the 1930s and 1940s, and named 3 new passerine subspecies in 1936. Between 1912 and 1950, 6 other newly-recognised bird taxa were given the epithet ‘steadi’. Four of these were indisputably named after Edgar Stead: Stictocarbo steadi Oliver, 1930, Pseudoprion turtur steadi Mathews, 1932, Thalassarche cauta steadi Falla, 1933, and Petroica (Miro) australis steadi Fleming, 1950. Carbo carbo steadi Mathews & Iredale, 1913 was probably named after Edgar Stead. It is suggested that Procellaria aequinoctialis steadi Mathews, 1912 was most likely named after the Australian naturalist David Stead (1877-1957). Among the birds named by or for Edgar Stead, only Thalassarche cauta steadi Falla, 1933, Xenicus longipes variabilis Stead, 1936, and Bowdleria punctata wilsoni Stead, 1936 are recognised as valid taxa in the 2010 Checklist of the birds of New Zealand. Stictocarbo steadi Oliver, 1930 is permanently invalid. A list of type specimens collected by Stead is presented, representing 6 currently recognised taxa.
Food preferences of the bellbird (Anthornis melanura), an endemic honeyeater, were determined by comparing the proportional use of plant species for nectar, fruit, and invertebrate feeding with the proportional availability (foliar cover) of plant species in forest remnants on the Port Hills, near the city of Christchurch, New Zealand. Of 529 feeding observations throughout the year, 56% were on invertebrates, 29% on nectar, and 15% on fruit. Invertebrate feeding predominated in all months except August to November, when nectar feeding predominated. Kunzea ericoides, Fuchsia excorticata, and Hoheria angustifolia were used more than expected from their foliar cover for invertebrate feeding, while F. excorticata, Sophora microphylla, Pseudopanax arboreus, and Phormium tenax were used more than expected for nectar feeding, and Coprosma robusta and Myrsine australis more than expected for fruit feeding. Little nectar was available in winter, which may explain why some bellbirds moved from the hills to the city at the end of the breeding season. However, more research is needed on the influence of temperature on these movements and on the resources used by bellbirds in the city.
On 5 years between 1969 and 2006, counts were made of birds seen and heard along a 2.3 km transect through a central suburb of Wellington City. A total of 14,461 birds of 26 species were encountered, including 10 native and 16 introduced species. Silvereye (Zosterops lateralis), sacred kingfisher (Halcyon sancta) dunnock (Prunella modularis) and rock dove (Columba livia) numbers remained similar over the 5 counts. By contrast, counts of tui (Prosthemadera novaeseelandiae), fantail (Rhipidura fuliginosa) and grey warbler (Gerygone igata) rose between 1988-89 and 2005-06. New Zealand pigeons (Hemiphaga novaeseelandiae) and bellbirds (Anthornis melanura) were 1st detected in 2005. The number of mallard (Anas platyrhynchos), song thrush (Turdus philomelos), chaffinch (Fringilla coelebs), blackbird (Turdus merula), goldfinch (Carduelis carduelis) and greenfinch (Carduelis chloris) increased more than 3-fold between the earliest and latest counts. Increases in the numbers of most native and introduced species may have resulted from a possum control programme that began throughout the Wellington district in the 1990s and to the establishment of the nearby Karori Wildlife Sanctuary (‘Zealandia’). Common starling (Sturnus vulgaris) and black-backed gull (Larus dominicanus) counts fell after 1971 as did the number of Australian magpies (Gymnorhina tibicen) between 1989 and 2005. Between 1969-71 and 1981-2, house sparrow (Passer domesticus) counts fell 37%, the figure remaining low until 2006. The coincidence of this decline in house sparrows with similar declines in the northern hemisphere is discussed.
Kowhai Bush in the Kaikoura region represents an important wildlife reserve for some native forest bird species. It is home of 1 of the few populations of brown creepers (Mohua novaeseelandiae) and South Island robins (Petroica australis) in lowland forest in the Canterbury region. Here, I present results from 275 five-minute point counts that were conducted at Kowhai Bush from October until December from 1999 to 2001. I compare these data with those collected by Gill (1980) in the same months of 1976 at similar sites. These comparisons reveal that the observed abundance and composition of the species at Kowhai bush has changed between 1976 and 1999-2001. Overall, there was a decline in bird abundance between 1976 and 1999-2001 and there was a significant difference in bird abundance between the 2 habitats in which counts were undertaken at Kowhai Bush. At a species level, there were dramatic declines (>50%) in the observed abundances of brown creepers and South Island robins whilst blackbirds (Turdus merula), redpolls (Carduelis flamea), and European goldfinches (C. carduelis) had more modest, but still significant declines. These declines were offset somewhat by large increases (>50%) in the observed abundances of silvereyes (Zosterops lateralis), and song thrushes (Turdus philomelos) and significant increases in the observed abundances of bellbirds (Anthornis melanura) and chaffinches (Fringilla coelebs). I discuss a number of factors that might be responsible for these changes.
Mohua (Mohoua ochrocephala) are endemic to the South Island of New Zealand but they have declined in both range and abundance. The causes of decline include predation from introduced predators and forest clearance. Mohua have survived in reasonable numbers in the Dart Valley in west Otago. In this paper we describe the relationship between the presence of mohua breeding territories and vegetation at a 1 ha scale within low altitude, red beech-dominated forest. The extent of shrub or regeneration was found to have the strongest association with the presence/absence of breeding mohua. Other factors which increase leaf volume, such as forest-edge and broken canopy were also important in explaining the presence of mohua. Milling was found to have a long lasting negative impact (>70 years) on mohua presence. Management which reduces grazing and increases the shrub and regeneration forest component is likely to increase mohua carrying capacity.
An annotated checklist of birds recorded or reported on the Aleipata Is, Samoa is presented. Nu’utele and Nu’ulua Is were the focus of an attempt to eradicate Pacific rats (Rattus exulans) in 2009. The data presented are from bird surveys intended to provide baseline information to determine the effect of rodent eradication on the bird fauna. Fanuatapu or Namu’a Is were surveyed as experimental controls. A total of 42 species were recorded or reported, comprised of 24 species of land birds (including 3 introduced species) and 18 species of seabirds and shorebirds. Morphometric data are also presented from Friendly ground-doves (Gallicolumba stairi) that were removed from Nu’utele I and held in captivity during the rat eradication attempt.
Information on the relevant spatial scale for controlling pest birds causing significant crop damage is generally lacking. Here, we assess the potential of 2 radiotracking systems (hand-held vs. elevated twin-Yagi antennae) for monitoring pest bird ranging behaviour on and around an arable farm. Radio-transmitters were fitted to 19 European greenfinches (Carduelis chloris) in the summer and 25 house sparrows (Passer domesticus) in the winter. Greenfinches were most likely to be detected in or near Brassica seed crops, particularly on the study farm, but 12% travelled large distances (>3 km) between Brassica crops in the landscape. Even though house sparrow home ranges were widely dispersed across the landscape, most overlapped with the farm boundary and were positively associated with woody vegetation. Relative to hand-held antennae, the elevated twin-Yagi system increased the detection radius for tagged birds from 100 m to 2000 m and also the number of location data, albeit over a more restricted area.