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

    Community conservation benefits Sulawesi flying foxes, but more is needed, experts say (11 Apr 2023 02:38:18 +0000)
    - Flying foxes play a vital role in maintaining forest health. As pollinators and seed dispersers they are also invaluable to the economic and social well-being of communities.
    - In Indonesia’s Sulawesi, conservation groups are working to protect flying foxes, which face threats including hunting for food and habitat loss.
    - Community-led approaches are showing success, but conservationists say greater protection and an expansion of projects is needed to protect more bat roosts.

    Study: Women, youths can be more effective at driving sustainable farming changes (07 Apr 2023 07:51:15 +0000)
    - A study in a farming community on Indonesia’s Sulawesi Island shows that women and younger farmers can be more influential than older men in persuading peers to adopt new technologies and practices.
    - The findings could have significant implications for conservation organizations trying to implement sustainable agriculture programs within communities.
    - The study looked at two groups — one made up of older men perceived as “opinion leaders,” and the other of mostly women and younger men — and how effective they were at convincing fellow farmers to try out a new pair of cacao pruning scissors.
    - Experts say the findings don’t mean older men no longer carry any weight when it comes to influencing community members, and that they should still be consulted and engaged with when introducing development initiatives.

    FOIA lawsuit suggests Indonesian nickel miners lack environmental licenses (24 Jan 2023 12:10:45 +0000)
    - A freedom-of-information ruling in Indonesia has indicated that two nickel miners suspected of polluting a river on the island of Sulawesi may not have all the required permits.
    - The ruling, in a case filed by environmental journalists, ordered authorities in East Luwu district to publish the licensing documents for the two companies, but the authorities said some of the papers were still being processed.
    - A lawyer for the environmental journalists points out that the companies should have already secured the licenses prior to operating, and that this revelation strongly points to them not having the licenses.
    - The Indonesian government is pushing a massive expansion of the nickel mining and processing industries to feed the demand for electric vehicle batteries, but nickel mining in the country has long been associated with pollution and community conflicts.

    From bombs to seasonal closure, Indonesian fishers move toward sustainability (21 Dec 2022 08:10:54 +0000)
    - Kahu-Kahu village on Sulawesi’s Selayar Island is implementing its first season- and location-based fishery closure.
    - The three-month closure of a 6-hectare (15-acre) stretch of coastal water is intended to replenish local octopus populations by reducing fishing pressure.
    - Local fishers will install and plant artificial reefs in the area during the closure.

    Sulawesi hydropower dam could flood important archaeological sites (14 Dec 2022 08:17:05 +0000)
    - A Jakarta-based hydropower company aims to dam the Karama River in western Sulawesi as part of a clean energy project to help wean the country off of coal.
    - An inundation map shows that the dam could raise the river’s water level to 62 meters (203 feet) above sea level, potentially damaging important archaeological sites in the Karama valley.
    - In 2020, archaeologists announced they had found Indonesia’s oldest-known rice strain in the Karama valley, an important region in the Austronesian expansion, thought to be one of the most expansive prehistoric human migrations.

    Fishers in Flores Sea opt to limit harvest of overexploited sea cucumbers (28 Nov 2022 12:24:16 +0000)
    - Fishers on Indonesia’s Sapuka island have decided to regulate their sea cucumber harvests.
    - Since the 1960s, sea cucumber has been an important commodity for the island, but heavy harvest pressure has pushed the fishery to overexploited status.
    - Sea cucumbers play a crucial role in the marine ecosystem by providing food to other species and adding nutrients and pH balance in waters around coral reefs and other shallow-water ecosystems.

    Sulawesi nickel plant coats nearby homes in toxic dust (17 Nov 2022 05:05:42 +0000)
    - The Bantaeng Industrial Estate is a 3,000-hectare ore processing zone in Indonesia’s South Sulawesi province.
    - President Joko Widodo has banned exports of raw mineral ores to compel companies to construct smelters to produce value-added nickel.
    - But South Sulawesi communities living alongside the smelters report health impacts from pollution generated on site. Relocation plans have yet to be enacted.

    Here come the sunbirds: New species from Indonesia’s Wakatobi Islands (09 Nov 2022 02:55:37 +0000)
    - A group of researchers have identified several new species of sunbirds whose range spans from Africa to Australia and the tropical Wakatobi Islands in central Indonesia.
    - They also found evidence that could divide the more widespread species of the olive-backed and black sunbirds, Cinnyris jugularis and Leptocoma aspasia.
    - The researchers said their findings reiterated recommendations to protect the Wakatobi Islands as an endemic bird area, especially as so much remains unknown to the scientific community.
    - The tiny archipelago is also part of the Wallacea region that many scientists consider “a living laboratory” for the study of evolution with endemic species being newly identified to science in recent years.

    Indonesian program pays fishers to collect plastic trash at sea (06 Oct 2022 10:57:41 +0000)
    - The Indonesian fisheries ministry has launched a four-week program to pay fishers to collect plastic trash from the sea.
    - The initiative is part of wider efforts to reduce Indonesia’s marine plastic pollution by 70% by 2025.
    - The country is a top contributor to the plastic trash crisis in the ocean.
    - Each of the 1,721 participating fishers will receive the equivalent of $10 a week for collecting up to 4 kg (9 lbs) of plastic waste from the sea daily.

    Sulawesi islanders grieve land lost to nickel mine (06 Oct 2022 02:03:53 +0000)
    - The Harita Group holds a nickel mining concession covering about 1,000 hectares (2,500 acres) on Wawonii Island.
    - The arrival of the mine has divided the community between those who support the development and farmers hoping to retain their fruit and nut trees.
    - One man described his grief as the grave of his son was exhumed and moved as a result of the mine.

    Faced with grouper, snapper decline, Indonesia adopts harvest strategy (23 Sep 2022 06:52:42 +0000)
    - Indonesia is adopting a harvest strategy for grouper and snapper in the east of the country, where catch volume and average fish landed are down.
    - The areas targeted are a major global supplier of the fish, given that Indonesia is responsible for 45% of global snapper and grouper sales.
    - The new regulations on gear and total boats targets restoration of fish stocks for seven species.

    Indonesia to update conservation efforts for aquarium favorite cardinalfish (21 Sep 2022 16:00:21 +0000)
    - Indonesia’s fisheries ministry says it is working on a new conservation road map for Banggai cardinalfish (Pterapogon kauderni), a popular species in the aquarium trade globally that is found only in the waters around the country’s Banggai Archipelago.
    - The fish is caught in large numbers — an estimated 500,000 to 900,000 individuals annually — and is exported mainly to the United States and Europe.
    - The updated conservation plan will evaluate the previous five-year plan for the cardinalfish, and use this to inform the national strategy for the next five years, the ministry said.
    - The cardinalfish’s habitat, the Banggai Archipelago, is considered to be in the heart of the Pacific Coral Triangle, which is home to the highest diversity of corals and reef fishes anywhere on the planet.

    Pioneer agroforester Ermi, 73, rolls back the years in Indonesia’s Gorontalo (15 Sep 2022 01:52:26 +0000)
    - Ermi Mauke, 73, has spent the past 40 years planting a mix of trees on the fringe of Bogani Nani Wartabone National Park in eastern Indonesia’s Gorontalo province.
    - Small farmers here have produced palm sugar for centuries using traditional techniques, but their labor-intensive methods face challenges.
    - Ermi’s self-taught agroforestry system yields varied food commodities that help meet her family’s daily needs while safeguarding the landscape.

    Scientists develop AI that can listen to the pulse of a reef being restored (25 Aug 2022 12:23:01 +0000)
    - Scientists have developed a machine-learning algorithm that can distinguish healthy coral reefs from less healthy ones by the soundscape in the ecosystem.
    - Previous studies had established that the sounds of life in a successfully recovered reef are similar to those from a healthy reef, but parsing all the acoustic data was slow and labor-intensive.
    - The new algorithm has been hailed as “an important milestone” for efficiently processing acoustic data to answer the basic question of how to determine the progress of a reef restoration program.
    - Researchers say follow-up work is still needed, including to check whether the algorithm, tested in the Pacific Coral Triangle, also works in reefs in other parts of the world.

    Aziil Anwar, Indonesian coral-based mangrove grower, dies at 64 (16 Aug 2022 07:52:31 +0000)
    - Aziil Anwar, a civil servant turned award-winning mangrove restorer, has died from diabetes-related complications.
    - Aziil gained prominence in the 1990s by pioneering a way to boost the success of mangrove planting in coral damaged by blast fishing on the island of Baluno in Indonesia’s West Sulawesi province.
    - With the help of local children, he managed to plant some 100 hectares (nearly 250 acres), fully covering the island and extending the mangrove forest out toward the mainland.