Mentawai Islands
Mentawai may refer to:
* Mentawai Islands, Indonesia
** Mentawai Strait
** Mentawai people, ethnic group of Indonesia
** Mentawai language, their Austronesian language
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Language and nationality disambiguation pages ...
, located 150 kilometres west of
Sumatra
Sumatra () is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the list of islands by area, sixth-largest island in the world at 482,286.55 km2 (182,812 mi. ...
in the
Indian Ocean
The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...
. It covers an area of 3,838.25 km2 including smaller offshore islands, and had a population of 35,091 at the 2010 Census and 40,220 at the 2020 Census; the official estimate as at mid 2023 was 41,899.Badan Pusat Statistik, Jakarta, 28 February 2024, ''Kabupaten Kepulauan Mentawai Dalam Angka 2024'' (Katalog-BPS 1102001.1301) A part of
Indonesia
Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania, between the Indian Ocean, Indian and Pacific Ocean, Pacific oceans. Comprising over List of islands of Indonesia, 17,000 islands, including Sumatra, ...
, the island is the most important home for the
Mentawai people
Mentawai (also known as Mentawei and Mentawi) people are the Austronesian people of the Mentawai Islands (principally Siberut, Sipura, North Pagai and South Pagai) about 100 miles from West Sumatra province, Indonesia. They live a semi-nomadic hu ...
. The western half of the island was set aside as the Siberut National Park in 1993. Much of the island is covered with
rainforest
Rainforests are forests characterized by a closed and continuous tree Canopy (biology), canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforests can be generally classified as tropi ...
, but is subject to commercial
logging
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucksKaramajet and Masokut which lie in the Bungalaut Strait to the south of the island.
The island is known for its range of
primate
Primates is an order (biology), order of mammals, which is further divided into the Strepsirrhini, strepsirrhines, which include lemurs, galagos, and Lorisidae, lorisids; and the Haplorhini, haplorhines, which include Tarsiiformes, tarsiers a ...
s, including the Kloss gibbon (''Hylobates klossii''),
pig-tailed langur
The pig-tailed langur (''Simias concolor''), monotypic in genus ''Simias'', is a large Old World monkey, endemic to several small islands off the coast of Sumatra in Indonesia. Its face is black, its fur is black-brown and it has a relatively sho ...
(''Simias concolor''), Siberut langur (''Presbytis siberu'') and Mentawai macaque (''Macaca pagensis'').
Siberut was affected by the
2004 Indian Ocean earthquake
On 26 December 2004, at 07:58:53 local time (UTC+07:00, UTC+7), a major earthquake with a magnitude of 9.2–9.3 struck with an epicenter, epicentre off the west coast of Aceh in northern Sumatra, Indonesia. The Submarine earthquake, undersea ...
tsunami
A tsunami ( ; from , ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and underwater explosions (including detonations, ...
, but without any known loss of human life. One report stated that the island may have been raised up to two metres by the earthquake.
Geography
Siberut Island has a hot and humid
tropical rainforest climate
A tropical rainforest climate or equatorial climate is a tropical climate sub-type usually found within 10 to 15 degrees latitude of the equator. There are some other areas at higher latitudes, such as the coast of southeast Florida, United States ...
, with an annual
rainfall
Rain is a form of precipitation where water droplets that have condensed from atmospheric water vapor fall under gravity. Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth. ...
of . Temperatures range from , and humidity averages 81–85%. The east coast has many
islet
An islet ( ) is generally a small island. Definitions vary, and are not precise, but some suggest that an islet is a very small, often unnamed, island with little or no vegetation to support human habitation. It may be made of rock, sand and/ ...
s,
bay
A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a ''gulf'', ''sea'', ''sound'', or ''bight''. A ''cove'' is a small, ci ...
s and
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 group ...
s, and is covered with
mangrove
A mangrove is a shrub or tree that grows mainly in coastal saline water, saline or brackish water. Mangroves grow in an equatorial climate, typically along coastlines and tidal rivers. They have particular adaptations to take in extra oxygen a ...
forest extending up to wide before giving way to nipah forest. The west coast features mainly ''
Barringtonia
''Barringtonia'' is a genus of flowering plants in the family Lecythidaceae first described as a genus with this name in 1775. It is native to Africa, southern Asia, Australia, and various islands of the Pacific and Indian Oceans. The genus name ...
'' forests and is difficult to get to because of rough seas and steep cliffs. The hilly interior elevates to , with many streams eventually forming rivers in the
sago
Sago () is a starch extracted from the pith, or spongy core tissue, of various tropical palm stems, especially those of ''Metroxylon sagu''. It is a major staple food for the lowland peoples of New Guinea and the Maluku Islands, where it is c ...
-grove lowlands and swamp forests. There are also areas of
dipterocarp
Dipterocarpaceae is a family of flowering plants with 22 genera and about 695 known species of mainly lowland tropical forest trees. Their distribution is pantropical, from northern South America to Africa, the Seychelles, India, Indochina, Indo ...
primary forest
An old-growth forest or primary forest is a forest that has developed over a long period of time without Disturbance (ecology), disturbance. Due to this, old-growth forests exhibit unique ecological features. The Food and Agriculture Organizati ...
.
Biodiversity
Siberut has been isolated from the mainland Sunda shelf since the
Middle Pleistocene
The Chibanian, more widely known as the Middle Pleistocene (its previous informal name), is an Age (geology), age in the international geologic timescale or a Stage (stratigraphy), stage in chronostratigraphy, being a division of the Pleistocen ...
. This isolation has led to a much biodiversity, with about 900 species of
vascular plant
Vascular plants (), also called tracheophytes (, ) or collectively tracheophyta (; ), are plants that have lignin, lignified tissues (the xylem) for conducting water and minerals throughout the plant. They also have a specialized non-lignified Ti ...
s and 31 mammal species. Sixty-five percent of mammals and fifteen percent of other animals are
endemic
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...
at some taxonomic level, making Siberut unique. Of the 134 bird species found on Siberut, 19 are endemic at some taxonomic level.
There are four endemic primates: the bokkoi ('' Macaca pagensis''), lutung Mentawai/joja ('' Presbytis potenziani siberu''), bilou ('' Hylobates klossii'') and simakobu ('' Simias concolor siberu'').
Environment
Siberut was recognized as a
biosphere reserve
A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, funga, or features of geologic ...
in 1981. In 1993, the western part of the island was designated as a national park, covering an area of .
About 70% of the remaining forest outside the reserve is subject to logging concessions, some operative and others pending.
In 2001,
UNESCO
The United Nations Educational, Scientific and Cultural Organization (UNESCO ) is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) with the aim of promoting world peace and International secur ...
brought in a new phase of its Siberut Programme, with the intention of protecting the ecosystem through local development. This phase involves creating a partnership of local communities, conservation groups and local government, an approach which appears to be popular locally. However, poor governance and corruption has led to substantial
illegal logging
Illegal logging is the harvest, transportation, purchase, or sale of timber in violation of laws. The harvesting procedure itself may be illegal, including using corrupt means to gain access to forests; extraction without permission, or from a p ...
Some anthropologists believe that several thousand years ago, the Bataks of
North Sumatra
North Sumatra () is a Provinces of Indonesia, province of Indonesia located in the northern part of the island of Sumatra. Its capital and largest city is Medan on the east coast of the island. It borders Aceh to the northwest, Riau to the sou ...
may have been the first to settle here. However, there are now substantial differences in culture and language among the inhabitants. The Swiss anthropologist, Reimar Schefold spent years among the Siberut groups, the Sakuddei.
On the western parts of the island, there is a tradition of communal long houses known as '' uma''.