Mixed-species flocks of insectivorous birds were investigated at Kowhai Bush, Kaikoura, in monthly transect counts between July 1986 and June 1988. Four native species (Brown Creeper, Silvereye, Greg Warbler and Fantail) and two introduced species (Chaffinch and Redpoll) foraged in mixed flocks. Brown Creepers and Silvereyes appeared to behave as nuclear species by determining the direction of movement of mixed flocks. Mixed flocks were found throughout the day. The mean number of species per flock was 2.5 and the mean number of birds in flocks was 8.5. Mixed flocks were seasonal with none encountered during the main breeding period (Sep-Dec).
We give weights and measurements of 16 species of birds mist-netted in forest on Little Barrier Island, including 67 Whiteheads (Mohoua albicilla) and 111 Stitchbirds (Notiomystis cincta). The following criteria for distinguishing sexes were established. Female Whiteheads weighed up to 15.9 g and males weighed 16.1 g or more. Most female Stitchbirds had wings up to 92 mm long and most males had wings 95 mm or longer. Incidental observations of moult, ectoparasites and movements are recorded.
The Adélie Penguin and Antarctic Skua breed at Cape Bird, and nine other species have been recorded as visitors (Emperor Penguin, Chinstrap Penguin, Southern Giant Petrel, Antarctic Fulmar, Antarctic Petrel, Snow Petrel, Wilson’s Storm Petrel, Southern Great Skua, and Southern Black-backed Gull). Fewer birds were recorded as visitors at Cape Bird than have been recorded at Capes Crozier and Royds, possibly because Cape Bird gets less wind.
Post-moult dispersal of Paradise Shelducks (Tadorna variegata) in the Wanganui district was examined during 1987 and 1988 from hunting season band recoveries. Birds were banded at five locations, two coastal (Lakes Waipu and Marahau) and three hill country (Kakatahi, Parihauhau, and Mangamahu). Birds banded at different sites dispersed differently, with birds banded at the two coastal sites and Parihauhau more dispersive than those banded at Kakatahi and Mangamahu. Males dispersed more widely than females. Band recoveries were clustered into two separate groups, those from Kakatahi and Mangamahu, and a group comprising birds banded at coastal moulting sites and at Parihauhau. Coastal areas accounted for more than 70% of the hunting effort in the 1987 and 1988 hunting seasons, and it is suggested that the two groups of moulting birds be managed as separate population units.
The results of monitoring changes in Cattle Egret numbers in New Zealand and eastern Australia, recovery records for long-distance movements of marked birds from colonies in eastern Australia, and records for wing-tagged and colour-banded birds in the Hunter Valley of NSW indicate that a pattern of movement from the colonies occurs in waves in a south to south-easterly direction to Victoria, Tasmania and New Zealand during autumn and a return in spring. This movement can be described as migration. Although there is some circumstantial evidence, there is no confirmation that the same birds travel the same routes to the same destination each year. In the wintering areas they tend to restrict their activities to well-defined local territories. Significant numbers of birds remain in their natal area, however, where they may move relatively little, restricting foraging to a very limited local area for long periods, or be somewhat nomadic within a restricted region.
Please note: This newsletter is a Supplement to Volume 37 (4) of Notornis, not a Supplement to Volume 37 (3) as shown on the cover page. We apologise for this error.
A subantarctic population of the Fairy Prion (Pachyptila turtur) was studied at South Georgia in 1982-83. Full measurements of breeding birds are given, together with details of breeding habitat, the timing of the main breeding cycle events, and chick growth (weight and wing, culmen and tarsus length). Regurgitated food samples showed the diet to be mainly Crustacea (96% by weight), fish and squid comprising the rest. Of crustaceans, Antarctic krill made up 38% of items and 80% by weight. Copepods (four species, mostly Rhincalanus gigas) made up 39% of items but only 4% by weight; amphipods [three species, principally Themisto gaudichaudii made up 22% of items and 16% by weight. Diet and frequency of chick feeding are compared with those of Antarctic Prions and Blue Petrels at the same site; Fairy Prions are essentially intermediate.