Little Barrier Island, or Hauturu in Māori lies off the northeastern coast of New Zealand's North Island. Located to the north of Auckland, the island is separated from the mainland to the west by the Jellicoe Channel, and from the larger Great Barrier Island to the east by the Cradock Channel. The two aptly named islands shelter the Hauraki Gulf from many of the storms of the Pacific Ocean.

thumb|Topographic map of Little Barrier Island

Settled by the Māori between 1350 and 1650, the island was occupied by them until the New Zealand government declared the island a wildlife sanctuary in 1897. Since the island came under control of the government, it has been under limited access, with only a few rangers living on the island. The Māori name of the island means "the resting place of lingering breezes". Along with its larger neighbour Great Barrier, it was given its English name by Captain James Cook in 1769.

The island is a nature sanctuary which has been described by the MBIE as "the most intact [native] ecosystem in New Zealand". However, several invasive species were introduced by both Maori and European settlers, including cats, which were destructive to local small bird and reptile species until they were eradicated between July 1977 and June 1980 in what was possibly New Zealand's costliest pest control programme. This was followed by a rat eradication programme from 2004. A cost benefit analysis has been published.

History

left|thumb|Rāhui Te Kiri, one who authorities evicted from the island in 1896

thumb|240px|The island (in the distance) from over [[Great Barrier Island]]

Māori occupied the island for centuries prior to the first European visits, probably first settling there between 1350 and 1650 CE. The Ngāti Wai still on the island, including the chiefs Wiremu Te Heru Tenetahi and Rāhui Te Kiri and their family, and a few Europeans living on the island, were forcibly removed from the island by a group of officials, police and soldiers in 1896. Since 1897, there has always been a caretaker or ranger resident on the island.

Stone rows and heaps can be found to from the mouths of Te Waikohare and Tirikawa Streams. The largest is high and wide. The most extensive stonework is located in the northwest of the island, near the ridge south of Te Hue Stream, where it is spread over several hectares. This site includes a number of terraces, which are stone-faced or have stone retaining walls. There are also numerous stone heaps and rows, and several free standing stone walls. Its earliest volcanic activity is estimated to have occurred 3 million years ago and the latest 1.2 million years ago. The volcano is most closely related to two volcanoes over northwest, near Whangārei. The volcanic activity on the island is associated with the Coromandel Volcanic Zone, which later moved southwards to form the modern Taupō Volcanic Zone. The island was one of the final volcanic events in the zone, as most volcanism in the zone occurred between 18 and 4 million years ago.

The island is steeply sloping, and deeply dissected by ravines radiating from a central range that peaks at Mount Hauturu, whose altitude is . Te Titoki Point is the only area of flat land on the island.

Approximately 18,000 years ago during the Last Glacial Maximum when sea levels were over 100 metres lower than present day levels, Little Barrier Island was landlocked to the North Island, surrounded by a vast coastal plain where the Hauraki Gulf / Tīkapa Moana exists today. Sea levels began to rise 7,000 years ago, after which Little Barrier became an island separated from the rest of New Zealand. During the glacial period, a river formed by the Mahurangi River and Waitematā Harbour river flowed between Little Barrier Island and Great Barrier Island. In February 2013, there were reports of the critically endangered New Zealand storm petrel (Oceanites maorianus) breeding on the island.

thumb|left|A [[North Island kōkako feeding in a coprosma tree on Little Barrier Island]]

When Māori occupied the island, as much as a third of the island was cleared of forest. However, since the acquisition of the land by the New Zealand government, all but 20 hectares of the island have been reforested. In 2012, there were reports that a southern right whale may have calved near the island.

The island was, until recently, the last refuge for two species: the stitchbird and the wētāpunga. By 1883, the stitchbird was confined to Little Barrier Island due to introduced species and deforestation on the mainland. Thanks to the actions of Department of Conservation, the species has been reintroduced to several other offshore islands as well as some mainland sanctuaries that have predator-proof fences, such as the Bushy Park forest reserve. The wētāpunga, on the other hand, has been confined to this island since its extinction in the Northland and Auckland regions sometime in the 19th century. The last population continued to decline until the removal of kiore in 2004. Since then, the population has made a rapid recovery, and the species has been reintroduced to numerous predator-free places and islands as well.

North Island brown kiwi (Apteryx mantelli) live on Little Barrier Island. They were reported from there over a number of decades in the 19th century, but with no tangible evidence for a long time. Then, the naturalist Andreas Reischek collected an Apteryx mantelli there in 1882. Many years later, examination of the feathers of the specimen, which was held in the Natural History Museum, Vienna, yielded the louse Rallicola rodericki, which is known only from Apteryx mantelli living on Little Barrier Island, providing supporting evidence for the provenance of that specimen kiwi. The island's native population was supplemented with additional Apteryx mantelli that were transferred from the North Island in the early 20th century.

There are several invertebrate species that are only known from this island, namely the ground beetle Mecodema haunoho and the spiders Migas insularis and Stanwellia hapua.

Kākāpō (night parrots), also critically endangered, were first translocated to the island in 1982. They successfully bred there in the 1980s and 1990s with the support of supplementary food. They were all removed in 1999 so that kiore (Polynesian rats) could be eradicated from the island using poison bait. They were reintroduced in 2012; as of July 2017, their population on the island stood at 14. Hauturu is a test site to see if the kākāpō can breed and raise their young successfully without human intervention.

Invasive species

The Polynesian rat or kiore (Rattus exulans) was likely introduced as invasive species during the initial settlement of the island by Māori. As in other places where predatory species were introduced, small animals not accustomed to predation likely experienced a decline in population, being pushed towards endangerment or extinction. German wasps had been reported on the island by the 1980s. A potential relationship between rat eradication and decline in Vespula species has been reported,

See also

  • List of volcanoes in New Zealand
  • List of islands of New Zealand

References

  • Te Hauturu-o-Toi / Little Barrier Island Nature Reserve, Department of Conservation
  • Cultural Heritage of the Gulf (brief history on page 5)