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The distribution of Hutton’s Shearwater (Puffinus huttoni) in the Kaikoura ranges is restricted to the upper Kowhai River and Shearwater Stream catchments. Survey quadrats were established and colony boundaries mapped as baseline data for monitoring. The breeding population was estimated to be at most 134 400 pairs, less an unknown number of non-breeding pairs and unmated birds. Productivity in used burrows in the Kowhai River and Shearwater Stream catchments was estimated at 31% and 16% respectively. Numbers have declined since the 1880s. The species fits the IUCN category of ‘vulnerable’.

Early European naturalists and explorers, who of necessity spent much of their time near the coast, do not seem to have logged or noticed Caspian Terns. This notable species was not officially listed in New Zealand till about 1860. It was regarded as rather scarce throughout the 19th century and even well into the 20th century. Two possible explanations for this apparent scarcity are offered: (a) that, as it laid large palatable eggs in places that were usually accessible, it had become scarce after 800 years of hungry human (Polynesian) predation, and (b) that, like some other waterfowl, e.g. Pukeko, White-faced Heron, Royal Spoonbill, it is a comparative newcomer to New Zealand and has enjoyed a ‘boom period’ in the middle of the 20th century.

The Wellington branch of the Ornithological Society of New Zealand counted coastal birds along the shores of Wellington Harbour every month for two years in 1975-77 and again in 1986-88. Between the two surveys, giant petrels and Black-backed Gulls, which feed on offal, showed significant population declines; however, most other key species increased, particularly Little Shags, Little Black Shags and Mallards, presumably as the health of the harbour improved as discharges from abattoirs and sewer outfalls were reduced. The distribution of some species changed markedly between the surveys, away from Ngauranga and Pencarrow Head to Moa Point and Owhiro Bay, where raw sewage continued to be discharged into the sea.

The population dynamics of a local group of Kea (Nestor notabilis) was studied at a refuse dump in Arthur’s Pass National Park over the course of three successive summers. The mean number of birds that foraged at the dump during the summer was estimated as 20 juveniles, 10 subadults, and 36 adults. An average of 11% of these birds were females. The number of adults was quite stable across years. The total population of Kea in this area was estimated to be between 88 and 119, or in the order of 0.018 to 0.040 birds per hectare. Mortality did not exceed 16-20% per year for adult and subadult birds, but it was probably higher for younger birds. Male juveniles all appeared to disperse from the area within the first two years; female juveniles, on the other hand, were frequently resighted in subsequent seasons. This difference in behaviour was statistically significant. The abundance of fledglings suggested that as few as 10% of adult males may breed in any given year.