We estimated apparent annual survival of adult and young grey-faced petrels (Pterodroma macroptera gouldi) and age of first return to the natal colony of young birds from 2 colonies in the Bay of Plenty, New Zealand, between 1991 and 2008. We analysed the capture histories of 5844 adult birds and 928 chicks in a mark-recapture framework. The apparent adult annual survival rate was 0.89 after accounting for transience effects, which were greater at the mainland site (Mauao, Mount Maunganui) than on the island colony (Motuotau, Rabbit Island). Annual survival of young birds between fledging and 2 years of age was 0.844 for Mauao and 0.865 for Motuotau. Around 50% of fledglings that returned to their natal colony did so by 4 years of age, and by age 6, the probability of a fledgling returning was approximately 1.0. These are the first reliable estimates of these parameters for grey-faced petrels and are vital for models aimed at predicting the effects of natural perturbations or management interventions on breeding populations.
We report Records Appraisal Committee (RAC) decisions regarding Unusual Bird Reports received between 1 Aug 2008 and 31 Dec 2010. Among the 58 submissions accepted by the RAC are the 1st New Zealand records of streaked shearwater (Calonectris leucomelas) and straw-necked ibis (Threskiornis spinicollis), 2nd records of great shearwater (Puffinus gravis), semipalmated plover (Charadrius semipalmatus) and Franklin’s gull (Larus pipixcan), and 3rd records of little stint (Calidris minuta) and black kite (Milvus migrans). Other notable records included the 1st oriental cuckoo (Cuculus optatus) from the Kermadec Islands, a New Zealand dabchick (Poliocephalus rufopectus) near Nelson, and 2 records of Stewart Island shag (Leucocarbo chalconotus) near Lake Ellesmere, Canterbury.
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.
We investigated the population size and annual survival of Salvin’s albatrosses (Thalassarche salvini) breeding at the Western Chain, The Snares, New Zealand. A count of breeding pairs during incubation resulted in totals of 1100-1200 breeding annually on Toru and Rima Islets in the 3 years 2008-2010; none was seen breeding on Tahi, Rua or Wha Islets.The majority of adults bred annually. Based on banding and recapture the annual survival probability of breeding birds was estimated to be 0.967 while that of known-age birds banded as chicks in Feb 1986 was estimated at 0.939. A bird banded as a chick on the Bounty Is in 1985 was found breeding on Toru Islet of the Western Chain in the 3 years 2008-2010. This is the first record of a banded Salvin’s albatross breeding away from its natal island.
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.
Home range size, travel distances, and population density of the great spotted kiwi (Apteryx haastii) were investigated in the North Branch of the Hurunui River. Radio tracking was conducted on 10 great spotted kiwi between Dec 2007 and Apr 2008. The estimated minimum home-range sizes were determined using the concave polygon method and ranged between 19.6 ha and 35.4 ha, with a mean of 29.3 ha (± 1.6 SEM). The observed nightly distances travelled per hour varied from 7 to 433 m (n = 569). Most estimates of travel distances (73%) were clustered in the classes from 0 – 150 m/hour, and distances over 200 m/hour were seldom achieved (only c. 7% of distances). The kiwi population in the Mainland Island site on the western North Branch of the Hurunui River was estimated to hold around 290 birds in total. Population density for the entire North Branch area was estimated to be 2 pairs/km² and when including subadults, 5 birds/km². Our estimate of home range size is larger but with more variation than found in other studies. Differences in population density estimates between our study and those in the Hurunui and Arthurs Pass district may be due to different objectives and methods.