Rangitoto Island

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Location of Rangitoto island (marked in red).

Rangitoto Island as viewed from North Head.

Rangitoto Island is a volcanic island in the Hauraki Gulf near Auckland, New Zealand. It is separated from the mainland of Auckland's North Shore by the Rangitoto Channel. Rangitoto is an iconic landmark of Auckland as its distinctive symmetrical 260 metre (850 feet) high shield volcano cone is visible from much of the city. It is the most recent and the largest (2311 hectares) of the approximately 48 volcanoes of the Auckland Volcanic Field.

Rangitoto is Māori for 'Bloody Sky',^[1] with the name coming from the full phrase Nga Rangi-i-totongia-a Tama-te-kapua ('The days of the bleeding of Tama-te-kapua'). Tama-te-kapua was the captain of the Arawa waka (canoe) and was badly wounded on the island, at a (lost) battle with the Tainui iwi at Islington Bay.^[2]^[3]

1 Geology
2 History
- 2.1 Māori
- 2.2 European
3 Nature
4 See also
5 References
6 External links

[edit] Geology

Rangitoto was formed by a series of eruptions between 600-700 years ago. Scientists are in dispute about the length of the eruptions, which are thought to have lasted (with interruptions) for 10 to 200 years. In any case, the amount of mass that erupted from the volcano was about equal to the combined mass of all other eruptions in the Auckland Volcanic Field before.^[2]^[4]

The volcano is not expected to become active again, although future eruptions are likely (spoken in geological timespans) elsewhere in the wider area of the field. Subsiding matter during the cooling process has left a moat-like ring around the crater summit, which may be viewed from a path which goes right round the rim and up to the highest point.^[2]^[3]

The island is considered especially significant because all stages from raw lava fields to scrub establishment and sparse forests are visible. In some parts of the island, fields of lightweight, clinker-like black lava stones are still exposed, appearing very recent to a casual eye. Visitors walk through the lava fields and may also walk through some of about seven known lava caves - tubes left behind after the passage of liquid lava. The more accessible of the caves are signposted.^[2]

[edit] History

Rangitoto Island from One Tree Hill.

Bracken fern, Pteridium esculentum, Rangitoto Island.

Lava field with path and encroaching vegetation.

[edit] Māori

The relatively recent eruption of the island from the gulf depths means its creation is within historical memory of the local Māori iwi (tribes).^[2]^[4] The island is linked by a natural causeway to the much older, non-volcanic island of Motutapu, where it is possible to view the remains of Māori habitation caught in Rangitoto's eruption paths.^[4] Ngāi Tai were the iwi living on Motutapu, and consider both islands their ancestral home. Ngāti Paoa also has links with Rangitoto.^[5]

A number of Māori myths exist surrounding the island, including that of a Tupua couple, children of the Fire Gods. After quarreling and cursing Mahuika, the fire-goddess, their home on the mainland was destroyed by Mataoho, god of earthquakes and eruptions on Mahuika's behalf. Lake Pupuke in North Shore City was created in the destruction, while Rangitoto rose from the sea. The mists surrounding Rangitoto at certain times are considered the tears of the Tupua couple for their former home.^[2]

[edit] European

The island was purchased by the Crown in 1854, a very early date in New Zealand's colonisation by Europeans, and set aside as a recreation reserve in 1890. Nonetheless, for over 30 years, scoria was quarried from the volcano as building material for Auckland as well. During 1925-1936, prison labour built roads on the island as well as a track to the summit.^[3]

There are also some remains of WW II installations which supported the Auckland harbour defenses and were to house U.S. troops or store mines. The most visited installation is the old observation post on the summit. The shoreline on the north side of the island was used as a wrecking ground for unwanted ships, and remains of several of the wrecks are still visible at low tide today.^[6]

Starting in the first half of the 20th century, small holiday houses began being built around the island's edge. However, most have been removed since the legality of their existence was doubtful right from their start in the 1930s (the building of additional houses was stopped in 1937), and because the island has now become a scenic reserve. Some of the 140 of these baches are being preserved to show how the island used to be, once boasting a permanent community of several hundred people, including a good number of children. The buildings included some more permanent structures like a seawater pool built of quarried stones by convict labour, located close to the current ferry quay.^[7]

There are now daily ferry trips to the island from Auckland but overnight stays are not generally possible, though a campsite exists.^[3] A day trip allows plenty of time for the fit to walk to the summit and back, with stunning views of the harbour and city. An alternative to walking, a land train, co-ordinated with the ferry sailings, takes visitors to a short way below the summit.^[8]

[edit] Nature

There are virtually no streams on the island so plants rely on rainfall for moisture. It has the largest forest of pōhutukawa trees in the world,^[3] as well as many Northern rātā trees. In total, more than 200 species of trees and flowers thrive on the island, including several species of orchid, as well as more than 40 types of fern.^[2]

As lava fields contain no soil of the typical kind, windblown matter and slow breaking-down processes of the native flora are still in the process of transforming the island into a more habitable area for most plants, which is one of the reasons why the local forests are relatively young and do not yet support a large bird population. However, the kākā, a New Zealand-endemic parrot, is thought to have lived on the island in pre-European times.^[2]

Goats were present on Rangitoto in large numbers in the mid 19th century, but were eradicated in the 1880s. Fallow deer were introduced to Motutapu in 1862 and spread to Rangitoto, but disappeared by the 1980s. The brush-tailed rock-wallaby was introduced to Motutapu in 1873, and was common on Rangitoto by 1912, and the brushtail possum was introduced in 1931 and again in 1946. Both were eradicated in a campaign from 1990-96 using 1080 and cyanide poison and dogs. Stoats, rabbits, mice, rats, cats and hedgehogs remain a problem.^[9] As the area is a DOC-administered reserve (in partnership with the Tangata Whenua Ngāi Tai and Ngāti Paoa)^[1], visitors may not take dogs or other animals onto the islands.^[8]