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The relationships, adaptations, and habits of the extinct, endemic Finsch’s duck (Anas finschi Van Beneden, 1875) from New Zealand were determined from skeletal comparisons. Finsch’s duck, usually placed in the monotypic genus Euryanas Oliver (1930), was found to be most similar to the Australian wood duck (Chenonetta jubata). Because the differences are mainly those associated with loss of flight, Euryanas is synonymised with Chenonetta, and the species should now be known as Chenonetta finschi.

Breeding performance of brown teal (Anas chlorotis) nesting in a pastoral environment at Okiwi, Great Barrier Island, New Zealand was studied during 1997-99. Mean (SD) clutch size in 47 nests was 5.4 (0.9), eggs hatched in 74% of nests (n=50), and 66% of eggs (n=236) hatched. Of 31 females fitted with radio transmitters, the nesting attempt by 7 (23%) was not detected and the remainder fledged a total of 15 young, a mean (+SD) annual productivity of 0.5 (1.3) fledglings female-1. Most broods (72% n=32) became extinct within 10 days of hatching. Limited wetland habitat in the pastoral landscape concentrated nesting and brood rearing. Breeding statistics from this environment may not be representative of the wider population.

The importance of fisheries waste in the diet of Westland petrels (Procellaria westlandica) was assessed using 3 different techniques. Dietary studies showed that during the hoki (Macruronus novaezelandiae) fishing season (mid June – early September), fish waste formed c. 63% of the solid food brought back to the colony and fed to chicks. After the hoki season, fisheries waste contributed only c. 25% to the diet. A survey of Westland petrels at sea found that, although vessels fishing for hoki influence the petrels’ distribution, only a small proportion of the population appears to use this food resource at any one time. Satellite tracking showed that, on average, birds spent 1/3rd of each foraging trip near vessels, but they foraged over much wider areas than those occupied by the fishing fleets. Although fishery waste now forms a substantial component of the Westland petrel’s diet, the situation suggests opportunistic use of a readily available resource, rather than dependence.

Dispersal within New Zealand of Australasian shoveler (Anas rhynchotis), banded as duckhngs in Otago (n=489) and Southland (n=392) during 1971-1979, was determined from the locations at which 180 were shot by hunters. There were no statistically sigruficant differences in recovery distributions of Otago and Southland birds either when recovered in their year of banding (y-o-b) or in all subsequent years combined (later). About 50% of total recoveries were made in the y-o-b and 2-thirds of these from within 200 km of the banding site. Recoveries in later years were more widely distributed than those made in the y-o-b. North Island recoveries were 28% of total recoveries and were from most large coastal and lowland wetlands as far as Northland, 1400 km from the banding site. Recovery distributions of ducklings were not sigruficantly different from those previously determined for moulting adults banded in the same areas. However, ducklings in their 2nd year of life appear to be more distantly dispersed from their natal sites than during their 1st year or are adults from their moulting sites. We speculate that long distance dispersal may be undertaken mostly by birds that fail to breed in their natal regions in their 1st year of life, and that dispersing birds may become irregular breeders at varying distant locations.