Three feeding methods are described for Fantails (Rhipidura fuliginosa): hawking, flushing, and feeding associations. Hawking Fantails cover large distances, use any available perch, and often feed above the forest canopy. Flushing Fantails cover small distances, perch on twigs and small branches, and feed mostly within the canopy or on the ground. Fantails in feeding associations feed where the species being followed feeds. Changes in the proportion of use of each feeding method in relation to breeding stage are described; the sexes did not differ
in feeding methods during breeding. By using several feeding methods, Fantails forage in a wider range of microhabitats and so may obtain a wider range of prey than they would by only one method.
In 1987, 3,776 kilometres of coast were patrolled and 4,124 dead seabirds were found, well below the average for the previous 17 years (10,624). Unusual finds were a White-bellied Storm Petrel (Fregetta grallaria), a Kermadec Petrel (Pterodroma neglecta) and a Red-tailed Tropicbird (Phaethon rubricauda). A summary is given of the coastal and monthly distributions for Procellaria species found during the 1960-1986 period. The most frequently recovered species was the Black Petrel (P. parkinsoni), the number found annually varying markedly.
The feeding behaviour of New Zealand Kingfishers (Halcyon sancta vagans) overwintering at Brooklands Lagoon, a coastal North Canterbury estuary, is described. Kingfishers watched for crabs from perches on or near the
mudflats and caught crabs on 96% of dives. Kingfishers then battered them against a perch; parts of the crabs such as the chelae were knocked off in the process. Fallen chelae (n = 225) provided information about species, size and sex of crabs taken. Crabs were collected in mud samples from 10 sites to compare the size, sex and species of crabs present on the mudflats with those taken by Kingfishers. Kingfishers fed only on the mud crab Helice crassa, which was the most abundant crab species on the mudflats. Male crabs and large crabs were taken more often proportionally than they were in the
mud samples.
The distribution of Banded Rails and Marsh Crakes in coastal Nelson, Buller and the Marlborough Sounds was surveyed between October 1980 and December 1982. Banded Rails and Marsh Crakes were found only in saltmarshes in Nelson and the Marlborough Sounds, though Marsh Crakes were difficult to detect and could have been more widespread. Banded Rails were found only in saltmarshes with a freshwater supply with stands of sea rush and mixed stands of jointed rush and marsh ribbonwood. The Nelson – Marlborough Banded Rail population consisted of about 100 breeding pairs and is isolated from the Banded Rail populations further north and south.
Birds in forest in the Orongorongo Valley near Wellington were caught over a 7-year period (1969-76) in mist-net rigs consisting of six nets one above another, forming a continuous curtain of nets from near ground level to the
forest canopy. We recorded which net in the rigs each bird was caught in, and described the vertical distribution of 14 species of bird. Hedgesparrows, Fantails, Tomtits and Blackbirds were caught more often in the lower nets,
Kingfishers, Silvereyes and Bellbirds were caught more often in the upper nets, and Moreporks, Riflemen, Whiteheads, Grey Warblers, Song Thrushes, Tuis and Chaffinches were caught more or less evenly at both levels. The vertical profiles differed between rigs. For the three species caught most commonly (Silvereye, Blackbird and Bellbird), the mean height of capture varied with time of day and with season. The vertical distribution is a useful characteristic in helping to define the niches of these birds.
Harrier diet and population dynamics were studied at Tekapo River in 1985 and 1986, and stomach contents were analysed from 239 specimens collected in the Cass Valley in 1983-85. Harriers in both study areas fed mainly on rabbits, including young live rabbits and carrion. Local changes in rabbit abundance led to changes in the distribution and numbers of harriers. Immature harriers were mainly transients and responded to changes in rabbit numbers more than adults did. When rabbits were scarce, the resident harriers fed more on alternative prey. such as skinks, but there was no corresponding increase in the numbers of birds eaten. Males fed on alternative prey more than females did. Males were outnumbered by females in the study area with lower prey diversity.
In 1986, 4,594 kilometres of coast were patrolled and 14,462 dead seabirds were found. Three new species for the Beach Patrol Scheme were the White-naped Petrel (Pterodroma cervicalis), the White-capped Noddy (Anous minutus) and the White Tern (Gygis alba). Four species found in greater numbers in 1986 than previously were the Yellow-nosed Mollymawk (Diomedea chlororhynchus), Narrow-billed Prion (Pachyptila belcheri), Short-tailed Shearwater (Puffinus tenuirostris) and Stewart Island Shag (Leucocarbo carunculatus chalconotus). A summary is given of the coastal and monthly distributions for each species of Pachyptila found between 1960 and 1986. The Fairy Prion (P. turtur), a New Zealand resident, was found most frequently mainly in February and between July and November. By comparison, the other five species, all migrants to New Zealand, were picked up mainly during July-August.
Since its recent arrival in New Zealand the Black-fronted Dotterel (Charadrius melanops) has begun winter flocking, and a newly observed feeding technique has become common. This new feeding behaviour is used mainly on hard substrate. The bird taps the substrate before pecking at prey, and on hard substrate the
capture rate is higher than by simple pecking. By imitating the tapping on soft, intermediate and hard surfaces, I found that vibrations from the tapping on hard substrate alone caused flies to jump, making them more visible.
In winter, birds were heard calling an hour before sunrise as they flew from sleeping sites scattered along the Manawatu River to the sludge ponds at the freezing works. The dotterels returned to the river after several hours of feeding but again visited the sludge ponds from mid-afternoon to almost an hour after sunset. At both the river and the sludge ponds most prey consisted of two species of fly. Daily time budgets showed that birds were feeding for 38% of the day while incubating, 69% while tending chicks and 86% during a winter’s day. It was estimated that during a winter’s day, one apparently normal bird caught 28,737 insects. To do this it pecked at 31,579 insects and caught one insect every 1.5 seconds.