Publications Archive

Observations of ducks on Macquarie Island in December 1985 and 1986 are summarised. Although the island has many wetlands, previous records suggest that ducks mainly use those within wet tussock grasslands in the lowland, coastal areas: recent observations confirm this. Reduced primary productivity on plateau wetlands may result in minimal secondary production of foods in a relatively harsh environment, one where nesting cover has been degraded by introduced rabbits and where predatory skuas are prevalent. Ducks, including hybrids between Grey Duck and the alien Mallard, used Square Lake and Duck Lagoon for feeding and resting, although their rate of feeding was higher at Square Lake. Broods were recorded only at Duck Lagoon, where Poa foliosa provides extensive cover. Introgression on Macquarie Island has occurred unsupported by local liberations, distant from human activity, and has implications for the gene pool of Grey Duck elsewhere.

Four surveys for Kokako were conducted in the Hunua Range between November 1986 and May 1988, by playing tapes of the local song dialect. Three of the four surveys were done in conjunction with the Auckland and South Auckland branches of the Ornithological Society of New Zealand. Forty Kokako were recorded, of which 12 were definitely in pairs, one was a definite juvenile and another a possible juvenile. Some of the remaining 26 were likely to have been paired. Thirty-eight birds were recorded in tawa-podocarp forest and two in adjacent second-growth scrub. The 40 birds ranged in altitude between 300 and 660 m ad. with an average of 490 m. They were distributed in the following catchments: Mangatangi (20 birds), Mangatawi (12), Orere (5), Tapapakanga (2) and Hauarahi (1). Most records were of birds heard rather than seen, and tape responses were low compared with those in surveys elsewhere. Comparisons are made with past surveys and survey techniques, and the discussion includes options for forest management in the Hunua Range.Ecology Division, DSZR, c/- Bulk Water Department, ARC, Private Bag, Auckland

The osteology of the New Zealand genera Mohoua and Finschia shows that they are definitely not referable to the Pachycephalinae or any other group within the corvine assemblage. This is in contrast to Sibley and Ahlquist’s original interpretation of their DNA-DNA hybridization studies and supports a recent reanalysis of that data by critics, who concluded that these genera belong among the “Passerida”. Within that group, the relationships of Finschia and Mohoua remain uncertain. No osteological basis could be found for continuing to separate the genus Finschia from Mohoua. The three species in the expanded genus Mohoua show increasing specialization for use of the hindlimb in foraging and in order of most primitive to most derived should be listed as M. novaeseelandiae, M. albicilla, and M. ochrocephala. The last two species are very distinct from one another osteologically and are not to be regarded as subspecies of a single species.

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.