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The results of biannual national wader counts done during winter (June–July) and early summer (November– December) by the Ornithological Society of New Zealand (OSNZ)/Birds New Zealand from 2005 to 2019 are compared with similar counts done in 1983 to 1994. Although the national wader counts continued 1995–2004 the coverage was insufficient to enable comparable analyses; however, reference is made to some sites that were counted continuously since 1983. At least 1,567 counts at 74 sites nationally resulted in 3,977,228 waders of 39 species being counted. The numbers of most species have declined since the 1983–1994 surveys, particularly evident in the northern hemisphere migrants, with the numbers of some species down by 50% or more. Such changes in numbers are likely to be a true reflection of the declining populations rather than changes in the counting effort. Some native species are faring better, mostly as a result of numerous community-led wader protection projects for northern New Zealand dotterels (Charadrius obscurus aquilonius) and variable oystercatchers (Haematopus unicolor).

More than 3,500 Holocene bones, representing at least 853 individual birds, have been recovered on the uninhabited subantarctic Auckland Islands, south of New Zealand. Today this island group has a rich seabird and land-bird fauna, although there have been at least four bird extinctions (a duck, two petrels and a plover) due to predation by introduced mammals and hunting by humans. The Holocene bone fauna, overwhelmingly from sand dunes on Enderby Island, is dominated by seabirds still found at the island group (particularly diving petrels Pelecanoides spp., southern royal albatrosses Diomedea epomophora, and prions Pachyptila spp.). Remains of all endemic taxa (apart from the Auckland Island tomtit Petroica macrocephala marrineri) were recovered from the deposits. All the taxa known to have gone extinct at the island group have now been recovered in Holocene bone deposits, except for the shore plover (Thinornis novaeseelandiae). The deposits indicate also that the abundance of other species has changed. For example, both the eastern rockhopper penguin (Eudyptes filholi) and white-chinned petrel (Procellaria aequinoctialis) are common in the Enderby Island deposits but are rare on the island today, and the Auckland Island rail (Lewinia muelleri) is present as bones in these dunes but has no historical records from the island. This information on the prehistoric distributions of birds will assist the management of the avifauna of the Auckland Islands, which is currently the subject of a major ecological restoration programme.

Since the European discovery of the Auckland Islands, at least ten species of land mammals have been introduced there. Most arrived in the first half of the ninteenth century during periods of exploitation by sealers and whalers, followed by short-lived Māori and European settlements at Port Ross. Several species required multiple introductions before becoming established. For those populations that naturalised, cattle (Bos taurus) occupied Enderby Island and were eradicated by 1993, goats (Capra aegagrus hircus) remained restricted to the northern end of Auckland Island and were eradicated by 1991, while pigs (Sus scrofa) spread across the entire Auckland Island and remain there today. Rabbits (Oryctolagus cuniculus) established on Rose and Enderby Islands, and were eradicated in 1993. Cats (Felis catus) and mice (Mus musculus domesticus) were both first recorded in 1840 on Auckland Island and remain there today. Rats (Rattus spp.) have never established on the Auckland Islands. Collectively, cattle, goats, sheep (Ovis aries), pigs, and rabbits transformed habitats and altered ecosystem processes, and suppressed tussock, megaherbs, and woody vegetation on Auckland, Enderby, Rose, Ewing, and Ocean Islands. Cats and pigs are together responsible for the extirpation or major reduction of surface-nesting and burrowing seabird colonies, and ground-nesting land birds from Auckland Island. Before dying out on Enderby Island, pigs had similar impacts there. Mice have altered invertebrate community composition and are likely responsible for lower abundancies of wētā (Dendroplectron aucklandense) and large weevils (Curculionidae) on Auckland Island. Disappointment Island remained free of introduced mammals, while on Adams Island they had only fleeting and minimal impact. Humans also had direct impacts on birds through hunting for consumption, with large surface-nesting seabirds severely affected around Port Ross. The Auckland Island merganser (Mergus australis) was driven to extinction by presumed mammal predation and well-documented museum collecting. Eradication of pigs, cats, and mice from Auckland Island and Masked Island (Carnley Harbour) would remove the last introduced mammals from the New Zealand subantarctic region.