Silvereyes (Zosterops lateralis) in an urban population in Marlborough, New Zealand showed considerable diurnal changes in body mass. At first light, average mass was 12.39 g, rising to 13.91 g by dusk. This represented a 12% average loss of mass overnight. The overall average mass was 13.22 g; birds were 6% below average at 0700 h, but increased rapidly to be near the average for most of the day, rising significantly in the 2 hours before dusk (1700 h). This pattern of diurnal mass change is consistent with theoretical models suggesting that birds should manipulate daily mass gain in order to trade-off starvation risk with mass-dependent predation risk.
We document hybridisation between South I pied oystercatcher (Haematopus finschi) and variable oystercatcher (H. unicolor) in Canterbury from 1989 to 2005. From 2 observations of hybridisation between South I pied oystercatcher x variable oystercatcher when first discovered, the hybrid swarm has increased to around 17 pairs, including South I pied oystercatcher pairs, variable oystercatcher pairs, hybrid pairs, and mixed pairs. We present data on the birds and their offspring and speculate on possible causes and implications of hybridisation for conservation of the taxa.
Evidence from Cook’s voyages supports the late prehistoric human introduction of the red shining-parrot (Prosopeia tabuensis tabuensis) from Fiji into the Tongatapu group, Kingdom of Tonga. It appears that a wild population of red shining-parrots was established on ’Eua by the time of Cook’s visits to the Tongatapu group in the 1770s. Latham used specimens obtained at ’Eua in 1777 for the 1st published description of the species. However, the correct type locality of the taxon is Fiji. A red shining-parrot specimen used by Latham is in the Naturhistorisches Museum in Vienna. It is 1 of the few bird specimens that survive from Cook’s voyages.
Prey remains and regurgitated pellets of New Zealand falcons Falco novaeseelandiae, from Adams I in the Auckland Is, were collected to determine the diet of this species in the subantarctic part of their range. Dissection of pellets revealed 1588 bones from 215 individuals of 18 species of birds preyed upon. Feathers associated with the remains supported the bone identifications. Rangle stones were also collected. The presence of procellariiform seabirds in the diet of falcons suggests some nocturnal hunting. While the single most frequent prey species was the bellbird (Anthornis melanura), Antarctic prion (Pachyptila desolata) and subantarctic diving petrel (Pelecanoides urinatrix exsul) were also common. When measured by prey weight, endemic land birds such as Auckland I rail (Lewinia muelleri), Auckland I snipe (Coenocorypha aucklandica aucklandica), and Auckland I teal (Anas aucklandica) constituted a third of the prey. Like many island birds, these ground-dwelling species cannot co-exist with introduced mammalian predators, but survive despite predation by native falcons.
The North Island robin (Petroica longipes) was introduced to the Zealandia – Karori Sanctuary in 2001. The sanctuary is a mainland island (225 ha) in Wellington that is free from all mammalian predators except mice (Mus musculus), and enclosed by a predator-proof fence. During 2001 and 2002 a total of 76 robins were translocated from Kapiti I to the sanctuary. To assess changes in this population since its introduction, I surveyed and mapped territories of robins in a 37 ha section of the sanctuary in 2008. Density has continued to increase, from 0.7 robins/ha in 2003 to 2.5 robins/ha in 2008. This density is higher than other mainland sites. Of 46 adult robins seen within the study area at the start of the 2004-05 breeding season, at least 17 remained within the area in 2008, close to their 2004 territories. These included 4 robins from the original transfer. In all cases where both partners from 2004 were seen in the study area in 2008, the pair bond remained intact. My survey confirms continued increase in this introduced population and high pair fidelity.
One significant late Holocene deposit of bird and other fossils was discovered during a brief survey of potential fossil sites on subantarctic Campbell I, New Zealand. The bones recovered included the first specimen of a Cyanoramphus parakeet from the island. Preliminary ancient DNA analysis of the parakeet bone confirmed its generic identification and may ultimately facilitate the re-introduction of a taxon that most closely resembles the genetic make-up of the extinct population. Some implications of the fossil record and value of the fossil sites are discussed.
The foraging behaviour and success of Australian white ibis (Threskiornis molucca) was investigated in a range of natural and artificial urban habitats in Queensland, Australia. Observations were made in tidal mudflat, freshwater wetland, rural grassland, urban park and landfill habitats. Australian white ibis exhibited a range of foraging behaviours, including both visual (fossicking, jabbing and pecking) and non-visual foraging behaviours (probing). The most common non-foraging behaviour was walking, followed by prey handling, pause and alert. Fighting was observed only in landfill habitats. Australian white ibis were able to capture food items in all habitats, although foraging success at landfills was more than twice as high as the other habitats. Food items captured at landfills required significantly more time to handle before swallowing. The ability of ibis to capture food items in all habitats indicates that they are effective habitat generalists.
An updated list of bird species identified at Washdyke Lagoon, Timaru, New Zealand is presented, along with the corresponding threat status and references relating to individual species. The information was based on a literature search of published or readily available information. Sixty-five species were identified (plus hybrids and unidentified species), which expands considerably on previous checklists from the lagoon. Eighteen species (nearly 28%) are threatened or at risk. The number and diversity of species identified emphasises the importance of the lagoon as a coastal wetland habitat on the central east coast of the South Island. The lagoon’s existence is under very serious threat from coastal erosion and a variety of human influences.
North Island kākā (Nestor meridionalis septentrionalis) often hold food in either their left or right foot when feeding. I observed kākā at Zealandia – Karori Sanctuary in Wellington in order to determine whether kākā show laterality (specifically footedness) when holding food. Laterality was seen at the individual level, i.e. individual kākā tended to consistently use the right foot or consistently use the left foot to hold food. However, there was no significant population level laterality, i.e. a similar proportion of the kākā showed bias towards using the left foot as the right foot. The kākā I studied were banded with a wide band on 1 foot and 2 narrow bands on the other foot. There did appear to be a population level bias towards holding food in the foot banded with the single wide band, but the reason for this was unknown and further study is needed.
An annotated checklist of the birds of Motu Kaikoura (Selwyn Island) in the Hauraki Gulf, New Zealand, is provided from surveys carried out between Dec 2006 and Jun 2008, supplemented by other recent observations. Thirty-seven species were recorded, including 25 species of land or wetland birds, and 12 species of seabirds and shorebirds. A total of 26 species were indigenous and 11 species were exotic. Motu Kaikoura was gazetted as a scenic reserve in 2004, with ecological restoration a key aim of its management. The 564 ha island has low vegetation diversity, reflecting a long history of anthropogenic degradation. Fallow deer (Dama dama), rats (Rattus spp.), mice (Mus musculus) and feral cats (Felis catus) were present on the island. Eradication of invasive mammals has been a management priority, with the bird surveys representing baseline data against which the progress of ecological restoration can be measured.
The distribution and habitat use of New Zealand pipits (Anthus n. novaeseelandiae) in Tongariro National Park on the volcanic plateau of the North I was assessed in Nov 1998 and Mar 1999. Pipits were found at 13 of 22 sites. Surveys between Nov 1998 and Oct 2009 found pipits present all year at Lake Te Whaiau, Mangatepopo Road and Waipakihi Road. Pipits were also seen along the road through the wetland at Erua in winter and summer. At Lake Te Whaiua, pipit presence and use of habitats differed seasonally. The average maximum flock size in summer was 9.7 (se = 1.05, n = 11). Maximum roadside counts outside of the flocking period were 1.13 pipits km-¹ (se = 0.17, n = 5) along Waipakihi Road and maximum summer flock sizes there averaged 6.0 (se = 1.05, range 2 – 18, n = 19) birds.
Here I report on a small scale study aimed at generating baseline information on the immune response of wild red-fronted parakeets, as assessed by blood cell counts, and subcutaneous challenge with phytohaemagglutinin (PHA), a mitogen that causes swelling at the point of injection. Eleven parakeets captured in mist-nets were injected into the right patagium with 0.5 mg PHA and the resulting swelling measured at 6 hours post-injection. Prior to PHA challenge, feather and blood samples were collected for detection of beak and feather disease virus and Plasmodium. Blood smears were also prepared for blood cell counts. Swelling occurred 6 hours post-injection in all but one individual, which tested positive for beak and feather disease virus. In this individual, no measurable swelling was detected. Estimated leucocyte counts, lymphocyte counts and heterophil counts of the same individual were similar to values of beak and feather disease virus negative individuals. Plasmodium DNA was detected in 2 individuals and their immune response was similar to that of parakeets testing negative for both beak and feather disease virus and Plasmodium. Estimated leucocyte counts, lymphocyte and heterophil counts did not differ between Plasmodium infected and non-infected individuals. The fact that the only individual testing positive for beak and feather disease virus showed no immune response to PHA challenge suggests increased susceptibility to other pathogenic infections. Although preliminary, this study highlights the potential damaging consequences of the accidental introduction of beak and feather disease virus in conservation programmes of threatened New Zealand parrots, some of which might already suffer from decreased immunocompetence resulting from reduced genetic diversity.