There are currently introduced pigs, cats and mice on Auckland Island. Auckland Island is the only island within the New Zealand Subantarctic Island Area with invasive mammalian pests. A project proposed by the Department of Conservation aims to remove these pests from the island, with feasibility trials started in 2018. DNA analysis suggests that mice—
Mus musculus—did not colonise Auckland Island from a New Zealand population but instead arrived with whalers or sealers from North America. They eat invertebrates, seeds, other plant material, native fish eggs and can eat bird eggs and chicks. They severely deplete invertebrate populations, reduce the seedbank, eat seedlings & plants and compete with birds for food resources. The impact of cats on the birds of Auckland Island was first noted by the Coastwatchers, who tamed some for company – the Ranui Station cats were recorded to kill 60 Antarctic prions over three months in 1942. Ornithologist Brian Bell found that prions were confined to cliff faces at Crozier Point in 1962 and noted "any bird landing...[fell] an immediate prey to the feral cats.". Gut content and scat analysis show that cats are feeding on small passerines and seabirds. A cat was seen feeding on a pre-fledging juvenile white-capped mollymawk at South West Cape. Goats were introduced to the Auckland Islands several times in the second half of the nineteenth century, to serve as a source of food for
castaway sailors, with at least one liberation in 1865 on the main Auckland Island. By the 1970s, only one population remained, a group of about 100 based on the northwest side of
Port Ross, in the north-east of the main island. Browsing by goats caused significant damage to lowland tussock
Chinochloa antarctica in particular. In 1986 and 1987, over 60 animals were removed from the island for captive breeding in New Zealand. A decision was made to eradicate the remaining animals, an operation which was completed by 1992. An investigation in 1999 into the fate of the translocated animals in New Zealand found that the breed had become extinct. Pigs—
Sus scrofa—were first introduced at Port Ross in the north of Auckland Island in 1807 by Captain Abraham Bristow and several further liberations occurred in the 19th century. The pigs were intended as a food source for shipwreck survivors and sealers.
Auckland Island pigs are a feral race of domestic pigs which are considered a distinct breed by the Rare Breeds Conservation Society of New Zealand. Pigs have had a severe impact on populations of
megaherbs, with populations of these plants on Auckland Island being almost totally depleted by the early 1900s.
Olearia lyalli is a tree
asterad native to New Zealand which may have arrived with humans in the 19th century. It is spreading from a historic settlement site at
Erebus Cove and covers neighbouring Ewing Island.
Harakeke, Phormium tenax, is found at Erebus Cove, Sealer's Creek, Ranui Cove and Tandy Inlet, and was introduced probably by the second wave of sealers to visit the island, to make rope, twine, baskets, mats etc.
Koromiko,
Veronica salicifolia, was first reported in 1975 around the Lindley Point farmhouse site at Deas Head, built in 1851. In February 2025, the Department of Conservation (DOC) announced a pest eradication project on the island. The project, part of the
Island-Ocean Connection Challenge (IOCC), targets three islands up to 15 times larger than any previously cleared of pests in New Zealand. The goal is to remove invasive species, restore ecosystems, and protect native wildlife, including
kākāpō, seabirds, and rare plants. The total project cost is estimated at $202 million, with $54 million from the government and $11.5 million raised through philanthropy, leaving $137 million still needed. == Human presence on the island ==