Aquatic invertebrates were extracted and identified from seven blue duck faeces collected from the Tongariro River in December 1990. A total of 927 aquatic invertebrates representing 37 taxa was identified. Over all samples, 45% of the aquatic invertebrates extracted were Chironomidae (samples ranging from 19-76%), 28% Trichoptera (ranging 11-49%), and 16% Ephemeroptera (ranging 2-42%). The dominant chironomid was Eukiefferiella sp., although Cricotopus spp. were also relatively abundant in some samples. Cased caddisflies were the main Trichoptera in all samples, but no one taxon was consistently dominant. Plecoptera comprised 0-20% of invertebrates in the faeces. In most samples collected below Tree Trunk Gorge, chironomids comprised ~61% of individuals recorded in the faeces, whereas above the gorge they comprised ~40% in any sample. Overall, the diet of blue duck on the Tongariro River in December 1990 was variable in terms of the proportions of species and the number of invertebrates that were consumed. This has also been shown in studies of blue duck diet on other rivers.
Preserved material from two kakapo (Strigops habroptilus), two kea (Nestor notabilis) and two kaka (Nestor meridionalis) was dissected. A fledgling kakapo had short, stout mandibles, a wide, thick tongue and a thick pharyngeal pad. The lower mandible closed against both the rostral end of the hard palate and the underside of the free end of the tongue. The crop was well defined. In the fledgling and in the headless body of an adult kakapo a fusiform proventriculus was followed immediately by an approximately spherical, uniformly muscular gizzard. There were five main intestinal loops and no evidence of a vitelline diverticulum or of caeca. In kea and kaka the upper mandible was longer, the tongue (especially in kaka) was narrower and fimbriated, and the crop was similar to that of the kakapo. The mandibles, tongue and palate of the kakapo appear to be particularly well adapted for the grinding of fibrous plant tissues to extract soft portions and juices.
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.
In 1989, 4194 kilometres of coast of New Zealand were patrolled and 8221 dead seabirds were found as part of the Beach Patrol Scheme. Unusual finds were a Snares crested penguin (Eudyptes robustus), two white-capped noddies (Anous tenuirostris minutus) and a brown booby (Sula serrator leucogaster). A summary is given of the coastal and monthly distributions of Pelecanoides, Phaethon and Fregata species found during the 1943-1988 period. Overall, 11 472 Pelecanoides urinatrix were found, but 10 or fewer of the other three species were found.
We assessed the numbers, distribution, and habitat of bristle-thighed curlews (Numenius tahitiensis) on Rangiroa Atoll, Tuamotu Archipelago, during a visit in April 1988. We estimated a total of 250-350 curlews on the atoll. These birds were seen only on the southern and western rims, where they were most common on (1) saltpans within clusters of small islets and (2) narrow channels between islets that were bordered by shrubs and herb mats. The distribution of curlews on Rangiroa appeared to be determined by the distribution of humans and their commensal animals and by the availability of habitats. Given the species’ relatively low numbers, low reproductive rate, and prebasic moult which, for some adults, entails a flightless period, conservation and management efforts must begin on the non-breeding grounds. These efforts should focus on reducing or eliminating potential mortality factors such as subsistence harvest, introduced predators, and contaminants. Countries throughout the species’ non-breeding range are encouraged to be active in these efforts.
In a 20-year nest box study of starlings (Sturnus vulgaris) in New Zealand, intraspecific fighting was the main mortality factor recorded. All fights were between birds of the same sex, 24 male-male and 22 female-female, and most were in the breeding season. Fighting increased as the population rose from about 300 birds in 1969 to over 3000 after 1978. Because of the low annual mortality rate of starlings in New Zealand (330/0), the chances of ever breeding were small for many birds. Hence conditions were ideal for a high level of fatal fighting, which took the form of grasping the opponent round the head so that the claws penetrated the brain through the eye sockets.