Public and our observations during 1999–2004 suggested that tūī (Prosthemadera novaeseelandiae) visited the city of Hamilton during March to October only, outside the nesting season. From 2004 onwards, we captured and banded 51 adult tūī and fitted radio transmitters to 41 in Waikato urban areas to locate nests. We directly observed 15 nests to determine nesting success and gather evidence of any predation events. Tūī moved 5–23 km from urban areas to surrounding native forests at the onset of nesting, but only four (29%) of 14 unmanaged nests fledged young, due mostly to predation by ship rats (Rattus rattus), swamp harriers (Circus approximans), and brushtail possums (Trichosurus vulpecula). Subsequent effective pest mammal control in forests around Hamilton was associated with greatly increased year-round tūī abundance and nesting in Hamilton. These results confirm previous findings that tūī move widely in winter; that they readily cross pasture in the absence of forest corridors, and that they will permanently inhabit urban areas. Provided adequate food is available, effective control of ship rats and possums can rapidly (1–4 years) increase tūī visits and nesting within 20 km of managed sites, enabling recolonisation of proximate urban habitats by this iconic endemic taxon, despite previous evidence for natal philopatry.
Abstract: We report Records Appraisal Committee (RAC) decisions regarding Unusual Bird Reports received between 1 January 2019 and 31 December 2020. Among the 149 submissions accepted by the RAC were the first New Zealand records of collared petrel (Pterodroma brevipes), South Polar skua (Catharacta maccormicki), and rose-crowned fruit dove (Ptilinopus regina). We also report the first accepted breeding record for gull-billed tern (Gelochelidon nilotica), and the sec- ond accepted sightings of Australian white-faced storm petrel (Pelagodroma marina dulciae) and buff-breasted sandpiper (Tryngites subruficollis). Other notable records included the first records of Atlantic yellow-nosed mollymawk (Thalassarche chlororhynchos) from the Snares Islands, nankeen kestrel (Falco cenchroides) from Antipodes Island, long-tailed skua (Stercorarius longicaudus) from the Chatham Islands, and Arctic tern (Sterna paradisaea) from the Bounty Islands.
Abstract: Birds were surveyed once per season over three years from 2015–2018 at Te Nohoaka o Tukiauau/Sinclair Wetlands, Otago. Eight species of waterfowl were observed, including four native species: New Zealand scaup (Aythya novaeseelandiae), Australasian shoveler (Anas rhynchotis), paradise shelduck (Tadorna variegata), and grey teal (Anas gracilis). Native species made up 68% of all waterbirds counted. New Zealand scaup dominated at 53%. The highest total number of birds counted was 1167 in winter 2015, and the lowest was 76 in spring 2016. The counts for some species varied greatly from year to year and each species showed some seasonal variation. It appears that more waterfowl are using the lagoons now than 15 years ago. Shag numbers were never greater than 8 individuals. The estimated density of fernbird (Bowdleria punctata) along a 750 m transect varied from 1.0/ha in winter to 2.7/ha in summer. This survey of waterfowl, shags and fernbird provides a reference against which future comparisons investigating long-term trends in bird populations at the Sinclair Wetlands can be made.
We found widespread nesting on the ground in a large population of feral rock pigeons (Columba livia) in an urban, but predator-free native forest reserve in Christchurch, New Zealand. Ninety-seven percent (n = 77) of rock pigeon nests were located on the ground, with most placed either at the bases of large kahikatea (Dacrycarpus dacrydioides) trees or under a tangle of vines on the forest floor. Clutch size was 2 eggs in all nests, with a hatching success of 93.9% in nests that survived to the hatch stage. Overall nest success was higher (60.0%) than in other populations of rock pigeons, with half of nest failures attributed to culling of the population that occurred during the course of our study. On average, rock pigeons fledged 1.60 chicks per successful nest. No ground nests were located outside the boundary of the predator- proof fence, suggesting pigeons were able to assess predation risk when selecting nest site location. Ground nesting by rock pigeons may be a way to avoid damage to nests in the canopy by strong winds or predation from aerial predators such as harrier (Circus approximans), which also occur in the reserve. Based on density of nests, we estimated a breeding population of 226 to 258 rock pigeons in the 7.8 ha reserve. The high number of pigeons in the reserve highlights the need for further studies on how populations of introduced species of birds in New Zealand respond to control of mammalian predators and the effect this may have on sympatric native species.