By Jeremy Hance


Land Areas: 174,600 square kilometers, making it the world’s 11th largest island (67, 413 square miles, 17.4 million hectares, or 43 million acres)
Human Population: 16 million (2005)
Country: Indonesia
Biodiversity: 1450 birds, 127 mammals, 5,972 vascular plants (2,225 of which are endemic)
Percent Forest Cover: Around 20%
Deforestation Rate: 2.35 percent annually between 1985-1997)
Causes of Deforestation: Agriculture, logging, and mining


Shaped like a lower-case 'k', the Indonesian island of Sulawesi is the world’s eleventh largest island. A treasure-trove of biodiversity with a startling number of endemic species (species that are found no-where else in the world), Sulawesi—formerly known as Celebes—has only recently become a target of conservationists. While much of the island remains unstudied by researchers much of its forest habitat has already been lost.

The tropical forests—which once covered the whole island—have been broadly deforested by agriculture, logging, and mining. The process accelerated in the late 20th Century when the government began supporting commercial logging and large agriculture projects. Locals also began converting forests into cash crops.

A study in 2007 found that 80 percent of Sulawesi's forest is gone or degraded, including almost the entirety of Sulawesi’s rich lowland rainforest and mangroves. The study further speculated that little deforestation in the future is possible since most of forest land that was useful for cultivation and logging is already gone. With few attractive commercial trees, Sulawesi’s highland forests have fared better, though many have suffered from degradation.


At 174,600 square kilometers, Sulawesi is the world's eleventh largest island just after Ellesmere Island in Canada. It is famously described as a big island with no interior, given that the island consists almost entirely of four interconnecting peninsulas.

Its large and winding coastline measures 6,000 kilometers. The island is surrounded on all sides by other big islands: Borneo to the west, Philippines to the north, the Maluku islands to the east, and Flores and Timor to the south.

Politically, Sulawesi is split into six Indonesian provinces: Mamuju (West Sulawesi), Manado (North Sulawesi), Palu (Central Sulawesi), Makassar (South Sulawesi), Kendari (Southeast Sulawesi), and Gorontalo. With 1.25 million people, Makassar is the largest city on the island; it rests on the southwestern peninsula.

The strange shape of Sulawesi—five connected peninsulas with little to hold them together—was created by a collision of multiple plates originating from Asia, Australia, and the Pacific islands.

The island contains thirteen freshwater lakes including the deepest lake, Matano, in Southeast Asia.


Sulawesi is largely dependent on crops and seafood for its economy: in 2004 agriculture made up 34 percent of Sulawesi's economy. Crops important to Sulawesi's economy include coconuts, nutmeg, soy, coffee, and rice. The island is one of the world's largest producers of cacao. It also produces a lot of cloves for kretek cigarettes.

Fishing, and increasingly aquaculture, has become important to Sulawesi's economy. Fish ponds and shrimp aquaculture has replaced much of the island's mangroves.

Other economic industries include commercial timber such as teak and rattan and tourism, which is seen as increasingly important by the government.

In 2004, 16.7 percent of Sulawesi's population were considered to be living in poverty. Most of the poor live in rural areas.


Sulawesi has a remarkable diversity of terrestrial flora and fauna and rich coastal marine life. Since the unique island sits on Wallace's Line it harbors species of both Asian and Australasian ancestors, though the majority are Australasian in origin.

On land, the percentage of endemic species is particularly noteworthy. Of 127 known mammals, 72 are endemic, making for one of the highest rates of endemic mammals in the world (62 percent). When bats are excluded—since they have better potential for migration—the percentage leaps to an astounding 98 percent. In addition, 34 percent of Sulawesi’s nearly 1500 birds are endemic.

Other fauna are unfortunately little studied. Twenty-five species of amphibian are known, forty lizards, and at least 52 terrestrial snakes. In addition, there are 38 species of large swallow-tailed butterfly, which so entranced Alfred Russell Wallace on his visit to the island. Researchers have also found 67 endemic species of fish in Sulawesi's dwindling mangrove forests.

Some standouts include:

  • Two wild cattle species, the Lowland anoa and the Mountain anoa. Both are listed as Endangered by the IUCN, little is known about these animals but they are heavily hunted for food and their horns.
  • The babirusa, also known as 'pig-deer, comprises three species of pig. Each male babirusa sports a set of four tusks, two of which stick through their snout. All three species are threatened with extinction.
  • The mysterious and little-studied Sulawesi palm civet which is classified as Vulnerable. This predator lives and hunts in a wide-variety of habitats.
  • The Crested black macaque is called the most threatened primate on Sulawesi. It is killed for bushmeat and caught for the pet trade. In addition, deforestation and mining have taken a large toll on its habitat. They used to occur in groups of over 100, but no longer. The species is considered Critically Endangered.
  • The maleo is an Endangered chicken-sized bird. They nest in traditional sites, over a third of which have been abandoned recently due to human impact. They lay one massive egg in meter-deep pits, which humans sometimes poach for food.
Newly discovered species include the Togian White-eye, a small olive black and white passerine, which is likely endangered; the Togian hawk-owl in 2004; a rediscovered species of pygmy tarsier in 2000; and fifteen new species of beetles in 2005.

The island's biodiversity is ripe for more discovery and study.


According to Middleton et al 2019, Sulawesi has 5,972 described species of vascular plants, of which 2,225 are endemic.


Sulawesi is surrounded by rich seas with large habitats of seagrass and coral reefs. These habitats are home to leatherback, hawksbill, and green sea turtles, as well as dugongs and six of the world's seven giant clam species. Whales that use the waters as a by-way include sperm whales, pygmy sperm whales, and killer whales.

One of the marine biodiversity standouts is the Sulawesi coelacanth. This is the second species of the prehistoric survivor and is classified as Vulnerable by the IUCN Red List because it is threatened as bycatch. The coelacanth is not a target for fishermen.


Sulawesi has a startling diversity of forest types: fourteen different forest ecosystems have been identified. The wide diversity of forests is part of the reason for the islands high rate of endemism and biodiversity.

Mangrove forests: found in estuaries and along Sulawesi's large coastline. At one time mangroves covered much of the coastlines, but most of these have been lost.

Montane forests: rising above 1,000 meters these forests are some of the most intact forests in Sulawesi. Lower montane forests are primarily made up of oak and chestnut species, while upper montane forests support a variety of conifers.

Monsoon forests: this unique forest type is little-studied. It receives the lowest amount of rain in all Indonesia and is able to survive long droughts. However, much of this forest type has been lost to grazing land.

Ultrabasic forests: a unique forest type that grows on nutrient-poor ultrabasic soil with little plant diversity, but high endemism since unique plants—like pitcher plants—have evolved to fill this niche. Ultrabasic forests are made up of short twisted trees. Few fauna live here.

Limestone forests: shallow soil and steep slopes make these forests low both in abundance and diversity. They are home to some endemic species like snails.

Peat swamp forest: though Sulawesi only has small areas of peat swamp forests they contain high biodiversity, especially of birds.

Freshwater swamp forests: like peat swamp forests, freshwater forests only cover a small area of Sulawesi. They are made up of palms, pandanus, and pitcher plants.


Approximately 80 percent of Sulawesi's forests are either gone or degraded to some degree. Over 50 percent are considered in poor condition, while 30 percent—mostly in the highlands (above 1500 meters)—are classified as in good condition.

Over 95 percent of Sulawesi's mangrove forests and lowland forests are disturbed. In less than a decade—between the mid 1980s and 1993—Sulawesi mangroves have been decreased by over 60 percent in part due to aquaculture for seafood such as shrimp.

Wetlands have suffered even worse: 99 percent of the island's wetlands are either gone or damaged.

Current rates of forest loss are lower than much of Indonesia, but this is primarily because much of the island's lowland forest was already gone by as early as 1985.

Forest loss is due primarily to logging and conversion. Beginning in the 1970s the government began supporting large-scale logging and vast agricultural projects. Since then migrants from urban areas to the countryside have converted large tracks of forest into cash crops such as coffee and cacao.

Million hectares200120102020Loss 2002-19% loss of 2001 cover
Primary forest area 9.8 9.5 9.0 0.8 8.2%
Tree cover area 15.6 15.5 14.3 1.3 8.3%



Large-scale loss of forest is not as big of a threat in Sulawesi as other islands in Indonesia, simply because there is relatively little forest left. However, deforestation of remaining forest would be catastrophic for the island's unique biodiversity, much of which are already threatened.

Since montane forests contain very few commercial species, they are relatively safe from loggers, but hunting, fires, and erosion due to cleared areas remain major threats.

Pollution and habitat destruction from mining poses a threat to biodiversity and ecosystem health. Mining is even reported to occur within the boundaries of protected areas.

Bushmeat hunting and poaching is a large issue for a number of endangered species, including anoa, babirusa, black crested macaques, and the maleo since its eggs are poached.

South Sulawesi, as opposed to north and central, is serviced by few parks and protected areas, leaving species and forests there particularly vulnerable.


Sulawesi has six national parks and nineteen nature reserves.

Central Sulawesi contains the most well-known park on the island, Lore Lindu National Park spanning 229,000 hectares. It is a UNESCO Biosphere Reserve.

On the northern peninsula, Bogani Nani Wartabone National Park protects 300,000 square hectares, while Rawa Aopa Watmohai National Park protects 105,194 hectares in southeast Sulawesi.

Most of the parks, however, suffer frequent encroachment for illegal logging, mining, and even conversion into crops. Thousands of illegal gold miners have been found plying their trade in Bogani Nani Wartabone National Park.

Sulawesi also has three national marine parks: Bunaken, Wakatobi, and Take Bonerate.

Bunaken National Park includes islands, mangroves, seagrasses, and coral reefs. Taka Bonerate National Park protects the Taka Bonerate atoll (and surrounding coral reefs), the world's third largest atoll and the largest in Southeast Asia. Last but not least, Wakatobi National Park is made up of island chains and 25 coral reefs.


Forest and coconut plantation in North Sulawesi


Crested black macaque

Crested black macaque

Flying dragon


Indonesian rainforest in Sulawesi

Indonesian rainforest in Sulawesi

Indonesian rainforest in Sulawesi

Indonesian rainforest in Sulawesi

Green Vine Snake

Male and Female Knobbed Hornbill

Strangler fig

Mother tarsier and baby


More images at the Sulawesi slideshow



  • Charles H. Cannon, Marcy Summers, John R. Harting, and Paul J.A. Kessler (2007). "Developing Conservation Priorities Based on Forest Type, Condition, and Threats in a Poorly Known Ecoregion: Sulawesi, Indonesia". Biotropica online 25 May to June 25, 2007.
  • Daws, Gavan and Marty Fujita. Archipelago: the Islands of Indonesia. University of California Press, Berkeley and Los Angeles. 1999.
  • Erdmann, M. 2008. Latimeria menadoensis. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.2.
  • Indonesian Biodiversity Strategy and Action Plan, 2003.
  • Indonesia National Socioeconomic Survey (SUSENAS), 2004.
  • Report on Biodiversity and Tropical Forests in Indonesia, USAID/Indonesia, 2004. Prepared by : (1) Steve Rhee, M.E.Sc. (2) Darrell Kitchener, Ph.D. (3) Tim Brown, Ph.D. (4) Reed Merrill, M.Sc. (5) Russ Dilts, Ph.D. (6) Stacey Tighe, Ph.D.
  • Ruud de Lang, Gernot Vogel. The Snakes of Sulawesi. Herpetologia Bonnensis II. Proceedings of the 13th Congress of the Societas Europaea Herpetologica. pp. 35-38. (2006)
  • Semiadi, G., Mannullang, B., Burton, J., Schreiber, A., Mustari, A.H. & the IUCN SSC Asian Wild Cattle Specialist Group 2008. Bubalus depressicornis. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.2.
  • Supriatna, J. & Andayani, N. 2008. Macaca nigra. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.2.

    Sulawesi conservation news

    Deforestation threatens to wipe out a primate melting pot in Indonesia (19 Oct 2020 08:39:00 +0000)
    - Unique primate habitats on the Indonesian island of Sulawesi are under threat from rising deforestation, according to a new study.
    - The island’s isolation has allowed macaques and tarsiers there to evolve in unique ways, leading to an “explosion” of biodiversity found nowhere else across Southeast Asia.
    - But logging, expansion of farmland, and infrastructure projects are driving a growing rate of forest loss, including in the “hybridization zones” that are a key factor in the island’s rich variety of primate life.
    - While protected areas exist on Sulawesi, they’re concentrated located at higher elevations, while most of the primates occur in lowland forests that can be more easily cleared and farmed.

    In Indonesia’s coastal villages, the plastic crisis is both homegrown and invasive (09 Sep 2020 01:24:53 +0000)
    - Proper management of plastic waste is lacking in Indonesia’s coastal communities, where the use of plastics is outpacing mitigation efforts, according to a newly published study.
    - The paper found that nearly 6,700 households in the Selayar and Wakatobi island chains had relatively low knowledge about plastic and how to manage it properly, while their use of it, particularly, single-use plastic packaging, was growing.
    - The researchers have called for producers to take greater responsibility for managing the waste generated by their products, and for a transition to a circular economy.
    - Indonesia is the second-biggest contributor of the plastic waste in the world’s oceans, behind only China.

    Indonesian fishers opposed to dredging project hit by ‘criminalization’ bid (28 Aug 2020 09:45:39 +0000)
    - Police have arrested four fishermen and charged them with defacing the Indonesian currency, following their protests against dredging for a new port in Makassar, eastern Indonesia.
    - Environmental activists and supporters of the fishing community say the charge, for which the fishermen could face up to five years in prison, is a spurious one meant to silence opposition to the $6.2 billion project.
    - The fishing community says the dredging activity has disrupted their traditional fishing areas, leading to catches dropping by up to two-thirds since dredging began in February this year.
    - The four fishermen arrested on Aug. 14 were charged after one of them, out of protest, tore a money-filled envelope given to them by the dredging company.

    Indonesian fishers face livelihood threat from ‘beautiful’ tourism project (27 Jul 2020 01:13:37 +0000)
    - The coastal district of Majene on the Indonesian island of Sulawesi is being developed to attract tourists.
    - Local fishers, however, have opposed the Waterfront City development project, saying it will damage the ecosystem that they depend on as their main source of livelihood.
    - Environmentalists also allege maladministration by the district government in allowing the project based on an environmental impact analysis that doesn’t square with the real impact on the ground.
    - The Majene government says it will continue with the project, calling the opposition one-sided.

    Indonesian miners eyeing EV nickel boom seek to dump waste into the sea (18 May 2020 00:15:53 +0000)
    - Nickel-mining companies in Indonesia have pitched the government to allow them to dump their waste, or tailings, into the sea.
    - The country is the world’s biggest producer of nickel, one of the key elements in the rechargeable batteries that power electric vehicles and energy storage systems.
    - Indonesia already has a copper and gold mine that practices deep-sea tailings disposal, or DSTD, with devastating impacts on the local ecosystem, activists say.
    - Indonesia and neighboring Papua New Guinea are home to four of the 16 mines around the world that practice DSTD, but account for 91% of the estimated 227 million tons of tailings dumped into the ocean.

    Indonesian anti-graft enforcers set their sights on a new target: corporations (31 Mar 2020 00:06:01 +0000)
    - Indonesia’s anti-graft agency, the KPK, is widely recognized for its prowess at catching corrupt government officials.
    - The agency has been less successful, however, at prosecuting companies on the other side of that corruption.
    - Recently, the KPK has begun to rethink its approach, with potential implications for natural resource firms that pay bribes in exchange for permits.

    Indonesia’s Lake Poso, an evolutionary ‘gem,’ threatened by dam (12 Mar 2020 08:59:11 +0000)
    - Around the turn of the century, the area around Lake Poso in Indonesia was wracked with communal conflict that left hundreds of people dead and thousands displaced. In the wake of this violence, local leaders embraced a hydroelectric project they hoped would help unite vying religious communities for a brighter future.
    - Fifteen years later, construction on the 515-megawatt dam is only half complete, and the company has informed the community it will need to reshape the mouth of the lake and dredge the river it feeds.
    - Local fishers fear changes to the lake and river will bring an end to traditional fishing practices that sustain thousands of families, while conservationists fear disruption to a unique and ancient ecosystem brimming with endemic species.
    - Activists have tried to mount a legal challenge to halt the project, but have been told by local authorities that they must first present scientific proof that the project will harm the ecosystem.

    One six-week expedition discovered ten new songbird species and subspecies in Indonesia (13 Jan 2020 17:33:37 +0000)
    - A six-week expedition to three small island groups near Sulawesi, Indonesia has yielded five new songbird species and five new subspecies.
    - The new species and subspecies were described in a paper published in Science last week. Frank Rheindt, a professor at the National University of Singapore, led the research team that made the discoveries using geological history and the notes of historical explorers as a guide in their search for new avian species.
    - While locals knew of some of the species already, it’s possible some of the birds had gone unnoticed because they sound more like insects.

    In Indonesia’s provinces, ditching coal for renewables would cut carbon and costs: study (24 Dec 2019 08:10:13 +0000)
    - Contrary to often-used arguments that fossil fuels are cheaper than renewable energy in Indonesia, a recent analysis found that shifting to renewables could actually cut both emissions and costs.
    - The analysis, part of a joint Indonesian-Danish energy program, was conducted in four Indonesian provinces. It found that if those provinces fully developed their potential renewable energy sources, they could save up to 11.5 million tons of CO2 by 2030 and nearly 40 trillion rupiah (US$2.8 billion) each year.
    - Each of the four provinces — North Sulawesi, Gorontalo, South Kalimantan and Riau — has significant potential for renewable energy generation, but local governments currently plan to rely on fossil fuels like coal to meet long-term energy demand.

    In Indonesia, a tourism village holds off a nickel mine — for now (08 Dec 2019 21:59:34 +0000)
    - Residents of the island of Kabaena in Indonesia registered their home as a “tourism village” seven years ago in a bid to ward off a planned nickel mine.
    - They say they fear that mining activity will disrupt their water sources and despoil the forests that they hold sacred.
    - Mining activities have proliferated in other districts in the province, driven by a boom for the nickel used in rechargeable batteries and stainless steel.
    - While the notion of being a tourism village has meant mining can’t proceed here, the villagers say they’re not getting the full support they expected to boost their economy this way.

    In Indonesia, a project meant to boost livelihoods has left locals behind (27 Nov 2019 08:31:49 +0000)
    - In Indonesia’s North Sulawesi province, work is underway to develop a special economic zone (SEZ) that will connect this remote region to the global economy.
    - Plans for the SEZ include a highway linking the port of Bitung to the provincial capital, Manado; a seaport expansion to rival Jakarta’s; an industrial zone; and an airport.
    - The development risks fragmenting the habitat of endangered and endemic species like the black macaque. Hundreds of families have also been relocated without compensation to make way for the project.

    Watchdog denounces arrests of four anti-mining activists in Indonesia (26 Nov 2019 10:20:31 +0000)
    - Police in South Sulawesi province have arrested a resident of the island of Wawonii in connection to his opposition to plans to mine the island for nickel.
    - The arrest comes just over a week after police detained and charged three university students over a protest against iron ore mining operations in Bima district, West Nusa Tenggara province.
    - Environmental activists have called the recent arrests part of a pattern of systematic efforts to silence community-led opposition to destructive mining activities.
    - Activists have called on the government and police to release the four protesters and investigate their allegations of violations by the mining companies in question.

    Indonesia protests: Land bill at center of unrest (03 Nov 2019 18:10:46 +0000)
    - In recent weeks, Indonesia has seen its largest mass protests since the “people power” movement that forced President Suharto to step down in 1998.
    - Among a variety of pro-democracy demands, the protesters want lawmakers to scrap a controversial bill governing land use in the country.
    - The bill defines new crimes critics say could be used to imprison indigenous and other rural citizens for defending their lands against incursions by private companies.
    - It also sets a two-year deadline by which citizens must register their lands with the government, or else watch them pass into state control. Activists say the provision would deal a “knockout blow” to the nation’s indigenous rights movement.

    For one Indonesian fisher, saving caught turtles is a moral challenge (23 Oct 2019 12:15:53 +0000)
    - Sea turtles are protected species under Indonesian law, but continue to be caught and killed for food and ornaments in many parts of the country.
    - Official wildlife conservation agencies are typically underfunded, and large-scale conservation programs run by NGOs are far from effective, a conservationist says.
    - But in a fishing village on the island of Sulawesi, a lone fisherman is playing his part by buying live turtles accidentally caught by other fishers and usually injured, and caring for them until they heal and can be released back into the ocean.
    - Conservationists have welcomed his initiative and intent, but raised questions about his expertise, with some of the more than 20 turtles he has cared for so far dying.

    Indonesian villagers fighting planned mine garner national support (22 Oct 2019 16:07:44 +0000)
    - Indonesia’s national human rights commission and the national ombudsman have weighed in on a dispute over plans to mine nickel on the remote island of Wawonii.
    - Residents have protested over the plans, which they say threaten their fishing grounds and freshwater sources.
    - Local authorities have sent out mixed messages on whether the project will proceed, while the company involved has continued clearing villagers’ land.
    - The rights commission has called for a halt to criminal investigations of the land defenders, while the ombudsman has called for all the permits to be scrapped.