The Celebes Sea lies in the western Pacific Ocean and is bordered by many island groups. From the north, it is surrounded by the Sulu Sea, Mindanao island and the Sulu archipelago. Towards the east, it is bordered by the Sangihe islands, from the south by Sulawesi and on the west by Kalimantan, Indonesia.
The Celebes Sea is situated within a tectonically active area of Southeast Asia. It is located on an oceanic plate north of Indonesia’s Sulawesi, towards the south of the Philippine islands and east of Borneo. The Makassar Strait opens the Celebes Sea to the Java Sea.
Now that we have talked about its location let us move on to some interesting facts about the Celebes Sea.
1. Celebes Sea stretches for 110,000 square miles
The Celebes Sea stretches for 675 kilometres from north to south and 840 kilometres from east to west. It covers an area of 280,000 square kilometres or 110 square miles and has a maximum depth of 6220 m or about 20,406.82 ft.
However, the seawater fills up a smooth basin with a steep side created by the downfaulting of a tectonic plate. Hence, more than half of the sea bed is over 13,000 ft or 4000 metres deep.
The EEZs of the Philippines and Indonesia pass through the Celebes Sea and Mindanao Sea, which is situated on the southern side of the Philippine Sea. Also, since the EEZs of these nations overlap, they negotiated an agreement about sharing the border or boundary line.
2. Formed Approximately 42 million years ago
The Celebes Sea was a part of an ocean basin that took shape around 42 million years ago. About 20 million years ago, the movement of the earth’s crust shifted this ancient basin close to the volcanoes of Indonesia and the Phillippines. Hence, the basin got the debris which was emitted by these volcanoes.
Around 10 million years ago, the Celebes was flooded with debris shed by these active volcanoes, and also coal. The latter was removed from a nearby mountain in Borneo, and the basin finally came to rest against Eurasia.
3. Captured by colonial powers in the 19th century
At the beginning of the 17th century, some regions of the Celebes Sea were considered quite strategic from the viewpoint of their location and availability of resources. Hence these were eyed by different groups. Ultimately, the Dutch and the Sang group established control over these areas.
Still, pirates were always a threat in the sea, especially in the 17th-18th century. Also, other traders, mainly from Borneo and closeby islands and coastal settlements, conducted trade through the Celebes Sea.
By the end of the 19th century, the Celebes Sea came under the purview of colonial powers.
This was because it was a strategic water body and played a crucial role in the regional maritime trade. It was also connected to nearby seas; establishing control over it was vital for conducting profitable business in Southeast Asia.
The Makassar Strait offered access to the Java Sea and Flores. The Celebes Sea area has been divided among the Philippines, the Republics of Indonesia and Malaysia. However, it was a centre of regional cultural and economic activities in ancient times.
4. Five Islands surround the Celebes Sea
Borneo, Sangihe, Sulu islands, Mindanao and Sulawesi, surround the Celebes Sea.
Borneo is the biggest island in Asia and the third largest in the world. It is administered by the government of three nations- Malaysia, Brunei and Indonesia. Locally, the island is called by many names; however, internationally, it is called Borneo.
It has been called Borneo since the 16th century after the Europeans encountered the Brunei Kingdom. Interestingly, it is also home to the world’s oldest rainforests.
Mindanao is the second biggest island in the Philippines and one of the most populous in the world. It is popularly known as the breadbasket of the Philippines. It has a stable economy supported by flourishing agricultural, fishing and forestry sectors.
Sangihe islands are found amidst the Celebes Sea and the Molucca sea. The group’s biggest island is Sangir Besar which also has an active volcano. Other islands include Siau, Tahulandang, and Biaro.
The Sulu archipelago is a chain of islands in the southwestern Philippines. There are three provinces, namely Tawi-Tawi, Sulu and Basilan.
Another famous island in the Celebes Sea is Sulawesi island, also known as Celebes island. It is one of the four Great Sunda Islands governed by Indonesia. It is the seventh biggest island in the world, covering 180,680 square kilometres approximately.
5. Sea Tang, a kind of seaweed is obtained from the Celebes Sea
The Celebes Sea houses a variety of marine mammals and plants. The tropical, warm and clear waters are the ideal habitat for many fish, which are economically significant.
Additionally, the sea also has 580 species of reef-building corals. They are some of the most diverse and support small fish and other marine creatures.
The waters also have whales and sea turtles, dolphins, manta and eagle rays, barracudas, pelagic species, marlins etc.
Tuna and Yellowfish tuna are caught from the Celebes Sea. It is also the source of another famous aquatic product called sea tang, a type of seaweed enjoyed by many, especially in Asian nations.
6. One of the most famous scuba diving sites in the world
The Celebes Sea is one of the world’s most popular and much-visited diving destinations. This is because of its diverse underwater topography and many coral reefs which support rare marine life.
It is mainly known for muck diving. The clear waters, breathtaking drop-offs and fast currents provide a perfect diving experience.
Many factors make it worth a visit. Firstly, the region lies amidst the Pacific and Indian oceans, inside the Coral Triangle. Secondly, you can find sandy regions, underwater walls, and cliffs with sharks and turtles.
Many diving areas in the sea have not yet been fully explored. This is because the island of Sulawesi is larger than Florida! Hence, only a part of its coastline has been explored.
There are very few diving areas, such as the Lembeh strait, Wakatobi National Park, Bunaken National Park and another one close to Derawan islands.
These sites offer a variety of diving experiences and opportunities, from drift dives to muck dives.
7. Has complicated oceanographic characteristics
The Sibutu-Basilian ridge forms the underwater boundary between the Sulu and the Celebes Seas. The latter has a rim that prevents cold currents from circulating in deep waters of the sea.
The Celebes Sea is one of the unique water bodies since its deep waters are warm. This is due to many factors like active volcanic islands, deep sea trenches, strong ocean currents, etc.
The Indonesian Through Flow enters from the Pacific to the Indian Ocean through the Celebes Sea.
Per scientists, the Celebes Sea has undergone little change, given the warm waters in its depths. Most oceans on the earth were similar to the Celebes Sea about 25 million years ago. They have called the sea waters’ an ancient, biological time capsule’.
Many studies are underway to understand the Celebes Sea since its depths have not been completely studied or explored.
8. Celebes Sea is prone to Piracy, armed robbery and other illegal activities
The Celebes Sea has been known for Piracy since pre-colonial times. Today, the area is also known for other illegal activities and poses a threat to nearby nations. The pirates not only loot fishing vessels but also eye huge container vessels.
They have sophisticated weapons, marine equipment, and high-speed crafts to chase ships. Although piracy incidents have declined considerably, the Celebes Sea is the second water body threatened by Piracy after Somalia’s Gulf of Aden.
Kidnappings, human trafficking, and dealings in arms and drugs have also made it a dangerous water body to tread on.
Since 2016, the abduction of ship crew has increased in the Celebes Sea. More than 80 such incidents have been reported in Asian waters. Hence, ships passing through these areas are issued warnings by the authorities.
9. Essential for maritime trade and commerce
The Celebes Sea coastline has around 24 ports. These ports belong to the Philippines, Indonesia and Malaysia.
The port of Kunak lies on the eastern coast of Sabah, Malaysia. It handles general cargo and palm oil exports. It has a jetty for loading and unloading essential commodities. It also ships timber, hemp and tobacco.
Manado is situated on the northwest coast of Sulawesi, Indonesia. It is a centre of trade and a significant port in the region. It handles local ships carrying general cargo. It exports ebony nutmeg, sugar, coffee, copra etc. It also operates ferry services to and from ports in the Philippines.
Port of General Santos, also called Makar, is situated on the northern shores of Sarangani Bay, south of Mindanao island. It is said to be the first modern and well-equipped port in the Philippines.
It can accommodate general cargo and bulk cargo carriers, breakbulk ships, RORO and even container vessels. The port exports fruit and juices, copra, coconut oil, tuna, veggies, flowers and livestock.
10. There are about ten settlements on the Celebes Sea
Some prominent settlements on the Celebes sea include the City of Cotabato, Manado, Tahuna, Pagadian, General Santos, Sandakan, Zamboanga etc. These are visited by travellers all year round as the Celebes sea has a tropical monsoon climate, with rainy summers and dry winters.
Cotabato is situated in the Philippines and is one of the most lively cities in the region. It has a stable and steadily growing economy with a strong banking sector. General Santos is quite urban and has modern facilities. It is also a trade and commerce hub.
Manado is one of Sulawesi’s biggest cities and a famous tourist destination. It is known for its picturesque landscape, lush green mountains and rich history.
Tarakan was a strategic town and a large oil producer during colonial times. It has grown substantially. Sandakan, previously called Iopura, was once the capital of British-controlled North Borneo. It is famous for its cultural heritage and natural beauty.
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Zahra is an alumna of Miranda House, University of Delhi. She is an avid writer, possessing immaculate research and editing skills. Author of several academic papers, she has also worked as a freelance writer, producing many technical, creative and marketing pieces. A true aesthete at heart, she loves books a little more than anything else.