Publications Archive

From 13 to 21 August 1992, we surveyed Breaksea and adjacent islands, Chalky and Preservation Inlets, and some of the coastline north of Chalky Inlet, for Fiordland Crested Penguins. Minimum total counts were 215 nests and 425 birds on Breaksea and adjacent islands, and 59 nests and 108 birds in Chalky and Preservation Inlets. Most nests on Breaksea and adjacent islands were under vegetation. Further south, nests were both in caves and under vegetation. Many apparently suitable caves did not contain penguins. The total absence of penguins from the outer coast reinforces our belief that we are finding most of the colonies in the survey area.

The previous distribution of the Shore Plover (Thinornis novaeseelandiae) and the possible reasons for its decline are outlined. The species is now confined to one small population on South East Island (Rangatira) in the Chatham Islands. In January and February 1993, we captured and banded or re-banded about 95% of this population and determined its age structure. Excluding juveniles of the 1992-93 season, 55% of the population is aged 6 years or less, 31% is aged between 7 and 12 years, and 14% is aged 13 years or more. The oldest bird currently alive is 18 years old. Estimates of population size and productivity for the season are compared with previous (mostly unpublished) records. Morphometric data are presented; there are small but significant differences in total head length, bill and tarsus between adult males and females, and in weight, wing and mid-toe between adults and 1-year-olds. In January, primary moult was more advanced in 1-year-olds than in adults.

A Kea (Nestor notabilis) is recorded as a fossil from the late Pleistocene of the North Island of New Zealand. Morphological and morphometric differences in osteology between the Kea and the Kaka (Nestor meridionalis) are described and discussed. Fossil and recent osteological specimens of the Kea and South Island Kaka have been confused in the past, resulting in Kea being identified as Kaka in collections and published lists. A fossil recorded as Nestor n. sp. in the Canterbury Museum is shown to be a South Island Kaka.

In 1990, as part of the Beach Patrol Scheme, 4,145 km of coast of New Zealand were patrolled and 7,145 dead seabirds found. An unusual find was a White Tern (Gygis alba). A summary is given of the coastal and monthly distributions of the eight Phalacrocorax, Leucocarbo and Stictocarbo species found during the 1943-1990 period. The Spotted Shag (Stictocarbo punctatus) was the most frequently found, mainly during February to June on Canterbury and Otago beaches.

Feeding observations of four species of Chatham Island endemic forest birds, Chatham Island Red-crowned Parakeet, Chatham Island Warbler, Chatham Island Tit and Chatham Island Tui, were collected on South East (Rangatira) Island in March and April 1990. The autumn foraging patterns of the forest species were very different. Parakeets had a broad omnivorous diet, Warbler and Tit were entirely insectivorous, and Tui fed mainly on fruit and some invertebrates. Parakeets used the widest variety of food plant species, including those from both forest and saltmeadow habitats. the Tui was the most plant-specific forager, with over 60% of feeding in one forest tree species. Because food availability changes throughout the year, other plant species will probably be important at different times. All birds fed at relatively low levels in the forest, often on the ground. This behaviour would make them particularly vulnerable to predation and may explain why the birds have now almost gone from other islands of the Chathams group.

The migration pattern for Cattle Egret in south-eastern Australia and New Zealand (Maddock 1990) is further clarified as a result of intensified observations of patagial-tagged birds and reporting of arrivals and departures of flocks by the observation network of Project Egret Watch in Australia and OSNZ in New Zealand since 1989. Seasonal outward migration from colonies in New South Wales after the breeding season to winter feeding ranges elsewhere in NSW, in Victoria and Tasmania, with return to the breeding colonies has been confirmed. Marked birds have been located in the same winter ranges, after having been recorded in the breeding colony for up to four consecutive years. Two cases of birds migrating to different locations in consecutive years have been recorded. The main movement is southward, but some birds migrate northward. The mean distance for southward migration is greater than for northward migration. Staging along southerly and northerly migration routes has been identified. The pattern of arrivals and departures in New Zealand identified by Heather (1978, 1982,1986) has been maintained, with tagged birds from Australia found in 1990 and 1991, but to date no marked birds have been located back in Australia after being seen in New Zealand. Birds tend to be restricted to highly localised ranges at the winter destination, using pasture on a single property or adjoining or closely related properties. Australian winter locations are generally restricted to coastal plains. Movements from the colonies take place in waves over a period of three months after the breeding period, although variation in dates from season to season has been identified. Birds tend to return to their natal colonies but some degree of colony exchange has been identified, particularly between neighbouring sites.

Observations of seabirds during two visits in the yacht Towrore to the southern extremity of South America in the summer and autumn of 1984 and 1985 are summarised with comments on their status in South America. Rockhopper and Macaroni Penguins (Eudyptes chrysocome and E. chrysolophus) are commoner than in the past, but larger penguins were not found breeding and may be more vulnerable since penguins still appear to be taken for bait. Chile holds about a sixth of the world’s breeding Black-browed Mollymawks (Diomedea melanophrys), a tenth of the Grey-headed Mollymawks (D. chrysostoma), many Blue Petrels (Halobaena caerulea) and Narrow-billed Prions (Pachvptila belcheri), and some Southern Giant Petrels (Macronectes giganteus). The White-chinned Petrel (Procellaria aequinoctialis) probably breeds, and possibly the Fairy Prion (Pachyptila turtur), collected in the past, and Antarctic Cormorant (Leucocarbo bransfieldensis). The first Manx Shearwaters (Puffinus puffinus) for Chile were also seen in the Magellan Strait and near Cape Horn.

This paper presents bird records from the Kingdom of Tonga which do not fit into other publications about the extensive field work of the Brehm Fund South Seas Expedition. Results of the first ornithological survey of the small island of ‘Eua’iki are presented. Most remarkably, this island has small numbers of Vini australis and Clytorhynchus vitiensis, which became extinct on ‘Eua and Tongatapu at the end of the 19th century. Other new distribution records for C. vitiensis are presented, and the record of its distribution in Tonga is revised. Its absence from the larger islands in southern Tonga is a result of human disturbance, most likely the introduction of Rattus rattus, while in the Vava’u group, competitive exclusion by Pachycephala jacquinoti may be the reason. Hirundo tahitica is now known from many locations. Breeding colonies seem to exist on Tofua and Nomuka, and a breeding population is probably establishing on ‘Eua. A few new data are added to the sparse knowledge about Pachycephala jacquinoti. Ardea novaehollandiae was recorded again from Tongatapu and Circus approximans for the first time from Tongatapu and Niuafo’ou. Records of Prosopeia tabuensis from Tongatapu and two of its offshore islands are given, and some remarkable changes in behaviour of Porphyrio porphyrio on small islands are reported. The brown female morph of Gallicolumba stairii, which has been known from Fiji and Samoa, is also in Tonga. An unidentified storm petrel has been seen close to Tongatapu. Breeding has been confirmed for Pterodroma nigripennis and Sterna sumatrana on several islands in the Tongatapu group. Some new breeding records for noddies (Anous spp.) on islands off Tongatapu are presented. Observations of Procelsterna cerulea on ‘Eua suggest that the species breeds in the cliffs of the east coast. Sterna anaetheta certainly breeds in cliffs on the southern coast of Tongatapu. The discovery of new breeding colonies of Pterodroma nigripennis supports the hypothesis that the species is extending its range. Blue-crowned Lorikeets and Fiji Shrikebills have been isolated on ‘Eua’iki for more than a century. These populations, and others, are very small (fewer than 100 birds each). Their size and long isolation call into question the concept of Minimum Viable Populations.