The Auckland Island’s distinct environments support a range of significant fauna, with rare and threatened animals nesting, breeding and taking refuge in the island group. The most imposing of these rare fauna, especially when landing at Sandy Bay on Enderby Island are the Hooker’s (or New Zealand) Sea Lions.
Sandy Bay is one of the most important breeding colonies for this rare pinniped, which numbers just 10,000 in the wild and is listed as ‘Nationally Critical’ by the NZ government. During summer the colony at Sandy Bay is filled with breeding and suckling females and their young pups, corralled by enormous beachmaster bulls. Females are a pale creamy grey or brown, and can weigh up to 160 kg. The big males dwarf them, weighing in at up to 400 kg and sporting thick dark brown or black fur that grows in luxurious manes down their powerful neck and shoulders. Males fight throughout the summer for supremacy on the beach, claiming their harems of females and young. Small young pups are at risk of being crushed by rampaging bulls, and their mothers often move them off the beach into the surrounding rata forest once they reach 6 weeks of age. Juvenile and sub-adult males hang around the edges of the colony, looking for an opportunity to start their own harem and begin breeding. This means fighting the dominant bulls, and many younger males move off like the females into the forest and heathlands to lick their wounds and avoid the fierce competition on the beach. Females begin breeding at around 3-4 years old, but males have to wait until they are big enough to claim their own territory and mates, at around 8 years old.
The rata forest and dracophyllum scrub provides shelter for another rare animal, the Yellow Eyed penguin. One of the world’s rarest penguins, this small sea bird nests on the Auckland Island group, Campbell Island and a few places on New Zealand’s South Island. The twisted, dense and complex understorey of the rata forest gives a safe and sheltered place for rearing chicks. Compared with other penguins, the Yellow Eyed penguin has one of the longest chick-rearing stages with chicks taking up to 120 days to fledge. Unlike the Snares Crested penguin or other Subantarctic species, the Yellow Eyed penguin is largely solitary and does not form breeding colonies. When going out to sea to forage they may move in small groups, but disperse once they’re in the water. Feeding on small fish found near the sea floor, Yellow Eyed penguins are very vulnerable to changes in the ocean ecosystem. The population is currently considered to be in decline due to disease outbreaks and predation, making habitat havens like the Auckland Islands, especially pest-free Enderby Island all the more critical to the Yellow Eyed penguin’s survival.
Beyond the rata forest lie alpine and sub-alpine heath, also known as fellfield. The fellfields of the Subantarctic support a huge range of plant species, from the golden Bulbinella rossi (or Ross’s Lily) to tiny orchids and endemic gentians dotting moss and lichen micro-gardens. On this windswept and tussock-studded landscape Gibson’s and Southern Royal Albatross breed. Both members of the Wandering tribe of Albatross in the genus Diomedea, the Southern Royal and Gibson’s Albatross have wingspans of up to 3 meters and spend most of the year gliding over the Southern Ocean in search of food. Like most albatross both these species have strong fidelity to their breeding sites and breeding partners, returning every 2nd year to renew their connection to their nest site and ‘spouse’. Gibson’s Albatross nests almost exclusively in the high tussocks of Adam’s Island in the Auckland Island group, where the island’s pest-free state protects their eggs form predation by pigs and mice. A small number of Southern Royal Albatross nest on the fellfields of Enderby Island, with an estimated population of 50 pairs. Both these species of Albatross spend a year raising a single chick, with both parents involved in feeding and nurturing the young.
Along the rocky and kelp hung coasts of the islands, Southern Rockhopper penguins form breeding colonies. The can be seen on the rocks in large groups, emerging from the vegetation and porpoising through the water. Giant Petrels and Skua gulls are abundant on the islands, scavenging prey and hatching chicks during summer.
The Auckland Islands support many more fascinating species, with a number of animals found nowhere else. Seven bird species are endemic to the Auckland Islands including the flightless teal, tomtit, shag, rail, banded dotterel and snipe. A race of the New Zealand Falcon inhabits the Auckland Islands, as does the red-crowned parakeet, a relative of the extinct Macquarie Island parakeet.
Smaller terrestrial birds like the tomtit and parakeet feed on the extensive invertebrate communities of the Auckland Islands. The islands have the largest invertebrate population of any of the New Zealand Subantarctic islands; 200 species have been identified including and endemic genus and species of Weta. Invertebrates are preyed on by mice on Auckland Island, and birds are impacted by feral pigs.