Rangiroa ( Tuamotuan for 'vast sky') or Te Kokōta ( Cook Islands Māori for 'the

Hyades star cluster The Hyades (; Greek Ὑάδες, also known as Caldwell 41, Collinder 50, or Melotte 25) is the nearest open cluster and one of the best-studied star clusters. Located about away from the Sun, it consists of a roughly spherical group of hundreds ...

') is the largest atoll in the

Tuamotus The Tuamotu Archipelago or the Tuamotu Islands (french: Îles Tuamotu, officially ) are a French Polynesian chain of just under 80 islands and atolls in the southern Pacific Ocean. They constitute the largest chain of atolls in the world, extendin ...

and one of the largest in the world (smaller than Kwajalein in the Marshall Islands and Huvadhu in the

Maldives Maldives (, ; dv, ދިވެހިރާއްޖެ, translit=Dhivehi Raajje, ), officially the Republic of Maldives ( dv, ދިވެހިރާއްޖޭގެ ޖުމްހޫރިއްޔާ, translit=Dhivehi Raajjeyge Jumhooriyyaa, label=none, ), is an archipelag ...

). It is in French Polynesia and is part of the Palliser group. The nearest atoll is Tikehau, to the west. It is about northeast of

Tahiti Tahiti (; Tahitian ; ; previously also known as Otaheite) is the largest island of the Windward group of the Society Islands in French Polynesia. It is located in the central part of the Pacific Ocean and the nearest major landmass is Austra ...

. Rangiroa is home to about 2,500 people on almost . The chief town is Avatoru, in the atoll's northwest.

Geography and environment

The atoll consists of about 415 motus, islets and sandbars comprising a total land area of about . There are approximately one hundred narrow passages (

straits A strait is an oceanic landform connecting two seas or two other large areas of water. The surface water generally flows at the same elevation on both sides and through the strait in either direction. Most commonly, it is a narrow ocean chan ...

or passes), called ''hoa'', in the fringing reef. The atoll has a flattened elliptic shape, with in length and a width ranging from . The width of land reaches wide and its circumference totals up to . The

lagoon A lagoon is a shallow body of water separated from a larger body of water by a narrow landform, such as reefs, barrier islands, barrier peninsulas, or isthmuses. Lagoons are commonly divided into ''coastal lagoons'' (or ''barrier lagoons'') ...

has a maximum depth of and its surface is . It is so large that it has its own horizon.Rangiroa
Publisher: Centre d'Océanologie de Marseille. Accessed 14 February 2010 Due to its shallow depth, the currents that come in and out through the passes, together with the winds, can sometimes create interior storms. Because of their large size, and the existence of only two passes, each

high tide Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables c ...

creates a strong incoming current, while each low tide creates a strong outgoing current within the two passes. While flowing inward through Tiputa Pass, nearly 200 individual sharks will gather at the entrance to the pass, at a depth of . Led by the strong current, sharks can remain motionless. Divers are able to observe them without difficulty. Large manta ray, green sea turtle, and

humphead wrasse The humphead wrasse (''Cheilinus undulatus'') is a large species of wrasse mainly found on coral reefs in the Indo-Pacific region. It is also known as the Māori wrasse, Napoleon wrasse, Napoleon fish, Napoleonfish, ''so mei'' 蘇眉 (Cantonese), ...

are also seen. During summer (December-March), tiger and

hammerhead shark The hammerhead sharks are a group of sharks that form the family Sphyrnidae, so named for the unusual and distinctive structure of their heads, which are flattened and laterally extended into a "hammer" shape called a cephalofoil. Most hammerhe ...

are present. In January, large numbers of stingray gather in the Tiputa Pass, as do the hammerheads that feed on them.

Water and ecological problems

Like many atolls, Rangiroa has no permanent fresh waterbodies, and therefore no central water distribution system. Each household must collect and store rainwater in cisterns. As a result of excessive pumping, the freshwater lenses that form on the

coral reef A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups. C ...

s are now mostly

brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...

, leading to

saltwater intrusion Saltwater intrusion is the movement of saline water into freshwater aquifers, which can lead to groundwater quality degradation, including drinking water sources, and other consequences. Saltwater intrusion can naturally occur in coastal aquifers, ...

.The Ghyben-Herzberg Model
Accessed February 16, 2010 Some are additionally polluted by landfill. As atolls form on the surface of the ocean, freshwater supplies are contaminated by the burial of waste, often accumulated in unregulated dumps or buried only a few meters deep. Such problems of water supply and

waste management Waste management or waste disposal includes the processes and actions required to manage waste from its inception to its final disposal. This includes the collection, transport, treatment and disposal of waste, together with monitorin ...

are common on atolls with the adoption of contemporary living conditions, and are therefore structural, as in the case of Rangiroa. In addition to this inherent problem, the progress of

global warming In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...

and the consequent rise in sea levels threaten the island. In common with other atolls, Rangiroa's

ecology Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overl ...

and its viability as a permanent habitation for

humans Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, culture, ...

are based on a highly vulnerable ecosystem that is delicately balanced, so requiring careful resource management.

History

It is believed the first settlers arrived on Rangiroa around the 10th century AD. The first recorded Europeans to arrive on Rangiroa were Dutch explorers

Jacob le Maire Jacob Le Maire (c. 1585 – 22 December 1616) was a Dutch mariner who circumnavigated the earth in 1615 and 1616. The strait between Tierra del Fuego and Isla de los Estados was named the Le Maire Strait in his honour, though not without controver ...

and Willem Schouten during their 1615-1616 Pacific journey. They called this atoll, , or 'Island of Flies', because their landing party returned to the ship covered in black flies. Rangiroa appears in some maps as ''Nairsa'' or as ''Dean’s island''. John Byron, passing the atoll during his circumnavigation in 1765, named it for the Prince of Wales. This atoll was visited by the

Charles Wilkes Charles Wilkes (April 3, 1798 – February 8, 1877) was an American naval officer, ship's captain, and explorer. He led the United States Exploring Expedition (1838–1842). During the American Civil War (1861–1865), he commanded ' during the ...

expedition on 7 September 1839. During the 1950s, the economy of Rangiroa was driven by fishing and the production of copra. The inauguration of the

Rangiroa Airport Rangiroa Airport is an airport on the island of Rangiroa, French Polynesia . The airport is located on the northwestern edge of the atoll, 5.5 km southeast of Avatoru. The airport was built in 1965.

in 1965 allowed rapid development of the tourism industry as underwater diving facilities and hotels were built. Rangiroa Church

Administration

The atoll of Rangiroa is the chef-lieu of the

commune A commune is an alternative term for an intentional community. Commune or comună or comune or other derivations may also refer to: Administrative-territorial entities * Commune (administrative division), a municipality or township ** Communes of ...

of Rangiroa, which consists of two other atolls ( Tikehau and Mataiva) and a separate non-atoll island (

Makatea Makatea, or Mangaia-te-vai-tamae, is a raised coral atoll in the northwestern part of the Tuamotus, which is a part of the French overseas collectivity of French Polynesia. It is located southwest from Rangiroa to the west of the Palliser gro ...

Demography

Only two islands, at the northern end of the atoll, are permanently inhabited. , the total population on the atoll of Rangiroa was 2,473 inhabitants. The main villages are Avatoru (pop. 817), Tiputa (pop. 971), Ohutu (pop. 546), Taeo'o, Fenuaroa, Otepipi and Tevaro. Both Avatoru and Tiputa were built on neighboring islands, in length respectively. They are separated by the major Tiputa Pass. The other major pass of the atoll is Avatoru Pass, immediately to the west of the island of Avatoru.

Religion

As in the rest of the Tuamotu Islands, the majority of the inhabitants are

Christians Christians () are people who follow or adhere to Christianity, a monotheistic Abrahamic religion based on the life and teachings of Jesus Christ. The words '' Christ'' and ''Christian'' derive from the Koine Greek title ''Christós'' (Χρ ...

, as a consequence of missionary activity by both Catholic and

Protestant Protestantism is a branch of Christianity that follows the theological tenets of the Protestant Reformation, a movement that began seeking to reform the Catholic Church from within in the 16th century against what its followers perceived to b ...

groups. The

Catholic Church The Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with 1.3 billion baptized Catholics worldwide . It is among the world's oldest and largest international institutions, and has played a ...

administers 3 religious buildings on the atoll: the Church of St. Michael in Avatoru (''Église de Saint-Michel''), the Chapel of St. Anne in Otepipi (''Chapelle de Sainte-Anne''), and the Church of Our Lady of Peace in Tiputa (''Église de Notre-Dame-de-Paix''), all under the Archdiocese of Papeete based on the Island of

Economy

Pearls

The breeding of pearl oysters in the lagoon can produce black pearls. Black pearls (meaning the marine cultured pearls produced from the black lip pearl oyster shell, ''Pinctada margaritifera'') are abundant in the atolls of French Polynesia. These pearls, which have a wide range of natural colours, from white to dark and all shades of grey, are the only cultured pearls in the world with so many different natural colours as the famous green rose peacock. The technique to produce marine cultured pearls was developed in Japan and, except some minor details, is similar in French Polynesia. A mother of pearl bead is inserted in the animal together with a piece of tissue (mantle) taken from another pearl oyster. The piece of tissue, as a graft tissue, will develop quickly and will form a skin around the bead and then will deposit mother of pearl on the surface of the bead. Bead rejection is important and concern about 30 percent of the seeded shells, mainly because the graft tissue is not close enough to the bead. Even with perfectly round beads, only 20 percent of the pearls will be perfectly round at the harvest, about two years after the seeding. Pearl farming is done in more than 30 atolls of French Polynesia and is the main activity for numerous families in the Tuamotu archipelago. In Rangiroa, a few farms exploited about of water surface in the lagoon loaned by the Tahitian government. The biggest farm, Gauguin's PearlGauguin's Pearl
/ref> employed more than 50 local workers, with a strong impact on the economy of this 2,000 person atoll. A school dedicated to the pearl farming techniques and a research centre on pearl oysters are also implanted on the atoll of Rangiroa, which make it a kind of pearl centre for this industry.

Fishing

Essentially a part of food production, however, it is also exported to the island of Tahiti.

Viticulture

The atoll of Rangiroa is also known for its vineyards, which are unique in the world. The vines grow on the edge of a lagoon beside coconuts, and produce two harvests per year. The winery is in the heart of the village of Avatoru. The grapes are brought to the winery by boat. The creation of this vineyard came after much prior analysis, to find the best site capable of hosting the vines. The first vines were imported in 1992 and underwent tests for acclimatization and selection in the main islands of Polynesia, with the uncertainty of their adaptation to climate. Thirty varieties were imported from various parts of Europe. The vineyard is Domaine Dominique Auroy. The tests took place in: * The Austral Islands on the high Rurutu and

Tubuai Tubuai or Tupuai is the main island of the Austral Island group, located south of Tahiti. In addition to Tubuai, the group of islands include Rimatara, Rurutu, Raivavae, Rapa and the uninhabited Îles Maria. They are part of the Austral Isla ...

, *

Nuku Hiva Nuku Hiva (sometimes spelled Nukahiva or Nukuhiva) is the largest of the Marquesas Islands in French Polynesia, an overseas country of France in the Pacific Ocean. It was formerly also known as ''Île Marchand'' and ''Madison Island''. Herman ...

(

Marquesas The Marquesas Islands (; french: Îles Marquises or ' or '; Marquesan: ' (North Marquesan) and ' (South Marquesan), both meaning "the land of men") are a group of volcanic islands in French Polynesia, an overseas collectivity of France in t ...

archipelago), * Rangiroa (Tuamotu archipelago), * The plains and mountains of

. The atoll of Rangiroa was selected for the following reasons: absence of grapevine pest such as defoliating insects (e.g., Grape Phylloxera) and its proximity to Tahiti. The

varietal A varietal wine is a wine made primarily from a single named grape variety, and which typically displays the name of that variety on the wine label.The American Heritage Dictionary of the English Language, Fourth Edition, 2000.winepros.com.au. ...

s grown on the atoll include Carignan, Italia and

Black Muscat Black Muscat (or Muscat Hamburg) is a red ''Vitis vinifera'' grape variety derived from the crossing of the Schiava Grossa and Muscat of Alexandria by Seward Snow, Head Gardener to Earl de Grey at Wrest Park, Bedfordshire UK in 1850, according ...

Tourism

Tourism is a major economic activity of the island: daily connections with Tahiti, an exceptional lagoon and passes which are good sites for scuba diving attract a steady number of tourists. These are accommodated in hotels and family-run guesthouses, a small number of which exist on the island.

Scuba diving

Rangiroa is a major

underwater diving Underwater diving, as a human activity, is the practice of descending below the water's surface to interact with the environment. It is also often referred to as diving, an ambiguous term with several possible meanings, depending on contex ...

destination because of the lagoon's clear waters and diverse marine fauna. There are several highly-regarded and popular diving sites, particularly in and around the Tiputa Pass, which runs to the Avatoru Pass. Sedentary common bottlenose dolphins (''Tursiops truncatus'') are regularly seen at group play in the pass. Many forms of marine life are present in the atoll's waters, providing opportunities for observation to divers and snorkellers. Rangiroa-W

Popular diving sites are the Blue Lagoon, Avatoru Pass, Tiputa Pass, and ('the pink sands'). A notable site in the atoll is the Blue Lagoon, which is a smaller lagoon formed on the southwestern edge of Rangiroa. Its shallow waters accentuate the bright blue color of the water. are sandbars of pink sand located on the southeastern portion of Rangiroa.

Transportation

Air transportation is available from and to

, located on the Avatoru Island. There are flights to Tahiti and other atolls of the French Polynesia. A small road made of tarmac and coral chips circles the island of Avatoru.

Notes

References

External links

*
Island names

Official website of the Tourism Committee of Rangiroa

le Maire & Schouten

{{Authority control Atolls of the Tuamotus