DIVING IN NORTH SULAWEST BUNAKEN ISLAND AND THE LEMBEH STRAIT

BUNAKEN ISLAND: DIVING SITE RIGHT OFF MANADO

Bunaken Island (half hour boat ride from Manado) is a veritable paradise for snorkelers and divers. The coral is excellent, the water is balmy and the visibility is often over 30 meters. Divers describe the drop off at Liang Cove as spectacular with caves, gullies and caverns harboring an immense wealth of marine life, including many beautifully colored feather stars. Another group of islands a short boat away from Manado are the Manado Tua Islands which have fine diving and snorkeling and nice views from the mountains on the islands. There are about 20 dive spots to choose from. The best season is May to August.

Bunaken Manado Tua Marine Park embraces 75,265 hectares, including 808-hectare Bunaken and Manado Tua. Mando Tua is a dormant volcano outside of Manado that can be climbed in about for hours. On Bunaken there is large village with a number of boat builders. A number of resorts are strung along the coast the island. A number of the best dive sites are reached from the coast. Other can be reached in a short boat journey.

Bunaken is most famous for it spectacular drop offs, which occur on the perimeters of all the islands. Turtles, lion fish, moray eels and sharks are regularly seen. Sometimes whale sharks and dugongs show up.The Lembeh Straits on the other side of the peninsula is famous for its unusual sea creatures that are found nowhere else in the world, including the mimic octopus.

Bunaken is an 8.08 square kilometers island in the Bay of Manado, situated in the north of the island of Sulawesi, Indonesia. Bunaken forms part of the administrative city of Manado, capital of North Sulawesi. The marine Park around Bunaken is part of the National Park that also includes the ocean around the island of Manado Tua — or Old Manado, Siladen and Mantehage. Entrance fee is 25,000 rupiahs per person per visit.

There are 13 types of coral reefs in this park, dominated by edge ridges and block ridges of rocks. The most attractive view is the steep vertical drops that plunges down as deep as 25 to 50 meters. The 91 species of fish found in the Bunaken National Park include the locally known gusimi horse fish (Hippocampus), the white oci (Seriola rivoliana), yellow-tailed lolosi (Lutjanus kasmira), goropa (Ephinephelus spilotoceps and Pseudanthias hypselosoma) and ila gasi (Scolopsis bilineatus), Divers also regularly see mollusks such as the giant kima (Tridacna gigas), goat head (Cassis cornuta), nautilus (Nautilus pompillius) and tunikates/ascidian.

Bunaken-Manado Tua Marine National Park

Bunaken-Manado Tua Marine National Park covers a total of 89,065 hectares and was nominated to become a UNESCO World Heritage Site in 2005. The islands are close to Manado, a city of 420,000 people, but are separated from the mainland by a submarine trench that reaches a depth of 1,200 meters, and keeps these waters relatively free from city garbage and silt. The reserve is protected by law from spearfishing and coral or fish-collecting, as well as from dynamite fishing.

According to a report submitted to UNESCO: “This part of North Sulawesi was undergone multiple geologic stages. It is considered to be a ‘young’ continent of 5-24 million years of age which has undergone explosive volcanism more recently (1.5 to 5 million years ago) which resulted in the volcanic tuff that characterizes the existing topography. Manado Tua is an inactive volcano formed in a classical cone shape with a 27-45' slope. The island rises over 600 m above sea level, the highest elevation in the park. [Source: Ministry of Environment]

“Bunaken Island has volcanic origins with a significant amount of uplifted fossil coral. At the west and central part of Bunaken Island (71m high) there is a flat plateau about 5Om above mean sea level (msl). Nain Island is also a dome-shaped island, 139m in height and with a slope of 20-40". Mantehage Island is relatively flat and seems to be sinking into the sea. The island has extensive mangrove forest flats, partially separated by saltwater channels. Siladen is a low-lying coral sand island with no significant topography. Arakan-Wawontulap and Molas-Wori on the mainland of North Sulawesi are relatively flat areas at the base of volcanic hills. The park has unique bathymetry which is an attraction for divers. The absence of a continental shelf in the northern part of North Sulawesi allows the coastal area of the park to drop directly down the continental slope. The sea depth between the islands of the park is 200-1,840m deep.

“In the coral ecosystem alone, Bunaken National Park covers an area of 89,095 hectares. The larger North Sulawesi area (also possessing potential for future inclusion in this WH site) contains approximately 280,000 ha. The marine national park area is home to thousands of different species of fish, coral, endangered marine mammals and reptiles, birds, molluscs and mangrove species. The Sanghie-Talaud island chain immediately to the north of the national park area is equally diverse (440 species from 52 sites in 2.3 million hectares). The uniqueness of Bunaken and the wider North Sulawesi area is its density of diversity in close proximity to a growing and populous part of Indonesia.”

Dive Sites Around Bunaken Island

The following are representative of dive spots around Bunaken Island : 1) Lekuan Walls (I, II, III): This long wall at Bunaken is divided into three sites: the Lekuan I, II and III. Together they are the park's best. Steep walls are marked with deep crevices, sea fans and giant sponges. The shallows are filled with fishes. The wall, often protected from stronger currents, is frequented by bumphead parrotfish, turtles, and Napoleon wrasses.

2) Mandolin has a knockout reef crest and a wall that attracts thousands of fishes like schooling fusiliers, surgeonfish, unicornfish, and bannerfish. They are used to divers and are easily approachable. 3) Bunaken Timor: There are strong currents and lots of fish on this long wall. The shallow reef isn't as spectacular as some but there are turtles, sharks, eagle rays, and other big fish in the blue. Overhangs and small caves mark the wall.

4) Tanjung Kopi is a nice wall with a small school of barracuda and lots of sweetlips. Visibility in the shallows is not terrific but the numbers of fishes make up for it. Nudibranches and fire gobies are easy to spot here. 5) Siladen Island has a beautiful wall of soft corals that bloom when the current is running. The shallows are nice with lots of fishes and schooling snappers. 6) Muka Gereja is a pretty site with thousands of fishes in the shallows and deeper canyons that lead to the wall. 7) Barracuda Point, on northwest Montehage, is one of the furthest sites. A school of giant barracuda are regulars along with jacks and tuna.

8) Manado Wreck: This 60m (200ft) long German merchant ship sank near Molas Beach in 1942. It sits upright with the bow at 23m (78ft). The ship is split near amidships back to the stern, exposing the wheelhouse and cargo holds. Dives finish up on a nearby shallow reef. Expect 10-15m (30-50ft) visibility. 9) Other than diving-enthusiasts, ornithologists and amateur bird-watchers might find visiting Tangkoko Dua Sudara Nature Reserve entertaining.

Visiting Bunaken Island

Accommodation: On the island you have a choice amongst a number of homestays, with rates starting at Rp40,000 for one person a day, including full board. Some of the dive operators on Bunaken are offering more upmarket accommodation that has running water. You can also stay in the hotels in Manado and then book a daily package to Bunaken, usually leaving in the morning and returning in the late afternoon.

Tips: 1) Entrance tags and tickets can be purchased through marine tourism operators based in Manado and in the Bunaken National Park, or can be purchased from one of three ticket counters in Bunaken and Liang villages on the islands of Bunaken and Siladen. 2) You should be aware that during the absolute peak season months of July and August it usually gets VERY crowded. Many of the better resorts and dive operators will not be able to accept walk-ins during that time since they are already fully booked. Better make a reservation beforehand. 4) Try to hire equipment from larger firms as these are more reliable, but remember: the responsibility of checking the equipment is ultimately with yourself. 5) Most people eat meals prepared at the place they are staying. There are couple restaurants on the island and many places to eat in Manado. Try seafood, bubur manado and food made of coconuts/

Getting There: The island of Bunaken is easily reached from Manado by motorized boat, departing from Manado harbor, Molas, Kalasey and Tasik Ria beach. Most people take a boat arranged by their hotel. Ferries from Manado to Bunaken leave daily around 2 p.m (depending on the tide), except on Sundays, when they leave from Pasar Jengki near the Manado harbor. The return journey from Bunaken to Manado usually leaves early in the morning, at around 7-8 a.mThere are also charter boats that depart in the morning and return in the late afternoon. These are usually reserved for travel packages organized by agents or hotels. You can also explore the island on foot or you can take a boat to move from one dive site to the other

Manado Tua

Manado Tua (one by boat from Manado, near Bunaken) is an island distinguished by the majestic perfect cone of the extinct volcano that formed the island, which is capped with a rainforest on its summit. Around the island are underwater plateaus sloping from five meters to 30 meters, fringed by vertical coral walls plunging 25 to 50 meters down, and large caves with hanging coral reefs. Next to Manado Tua is the more well-known island of Bunaken.

Manado Tua— or Old Manado — together with the islands of Bunaken, Siladen, Mantehage and Nain form the Bunaken-Manado Tua Marine National Park. The Park lies just off shore from the city of Manado but is not as easy to get to as Bunaken. From Manado there are cabin cruises available to the Park or motorboats for hire. Most people visit the dive sites as part of a diving package. To enter the Park contact the Bunaken National Park Office at: Jalan Raya Molas, PO Box 1202, Manado, 95242, North Sulawesi Tel: 62-431-859022, E-mail: tnb@manado.wasantara.net.id

At Manado Tua you can find many big fish such as the napoleon wrasse, giant trevally, eaglerays, snappers, groupers, and--occasionally--a hammerhead shark. But as currents here can be strong, only advanced divers should venture in these waters and best be accompanied by a diver experienced to these surroundings. In 1997, coelacanth — the amazing fossil fish that lived 360 million years ago and was thought to have died out 66 million years ago — was discovered living within the Laval tubes in Manado Tua. Dugongs like to feed on seagrass towards the south of the park.

On the east coast of Manado Tua, at Tanjung Kopi, or Coffee Point on the reef underwater plateau there are blacktail barracuda and large schools of fish. Tanjung Kopi is also where hundreds of turtles lay their eggs at full moon. For those who do not dive, one can go snorkeling or watch the underwater sea life from glass-bottom boats. There are also jogging tracks and facilities for mountain biking and camping.

The island has some 3,200 inhabitants forming a tight-knit community of farmers and fishermen from the Sangir region. This community has been actively restoring damaged reefs with the assistance of Seacology. Here EcoReef--snowflake-shaped ceramic modules--have been placed as shelter for fish and to build new reef.

The Ministry of the Environment informs that credit for the preservation of the Bunaken-Manado Tua reserve is due to the Nusantara Diving Club which in 1985 urged the government to protect these amazing waters from pollution and damage from shipping, and to move Manado’s harbor to Bitung, on the east side of the peninsula.

Diving in the Park can be done year round, yet currents and waves can be rough between January through March. During the peak season in the months of July and August dive operators are busy, therefore it is best to book way in advance. Best dives are in August and September when one has a better chance to watch whales and dolphins glide by.

Lembeh Strait

The Lembeh Straits (on the other side of the northern Sulawesi peninsula from Manado) is famous for its unusual sea creatures that are found nowhere else in the world, including the mimic octopus. The underwater landscape is brown, mucky and sandy with lots of pebbles and rocks and often cloudy water, not colorful reefs and clear water you normally associate with diving. The main attraction is the strange sea life. David Doubilet wrote in National Geographic: “Think of a coral reef as Las Vegas: a glowing city of sexy fish flitting down boulevards of neon corals. Then imagine an undersea neighborhood that's more like the gritty desert beyond Vegas, where you run into quirky characters like the guy running the one-pump gas station, or the bar where people wait for aliens. That's Indonesia's Lembeh Strait. [Source: David Doubilet, National Geographic, November 2005]

“Lying off the northeast tip of the island of Sulawesi,sheltered from the open ocean, the strait is at first glance an unwelcoming moonscape—plains of silt and black and gray volcanic sands stretching into murky gloom. Some divers call it the muck. There are no grand vistas, no teeming corals. But any place you put your hand, there is life, veiled in the sand or hiding in plain sight. You have to look closely, for many things are not what they seem. I stared for minutes at a sea fan before finding pygmy seahorses the size of my thumbnail clinging to the branches, their skin matching the color and texture of the sea fan's polyps. Another night a rare visitor drifted into the cove of Kungkungan Bay, camouflaged in a floating mass of sargassum weed. As the seaweed slowly broke apart, a golden sargassum frogfish emerged in mirror image under the lights of a pier.

“At dusk the Lembeh Strait seems lit by fireflies as fishermen in outriggers use kerosene lanterns to attract baitfish for the tuna fishery far offshore. Sulawesi sits in the middle of the greatest concentration of coral reefs on the planet—a virtual coral Eden—so diving in Lembeh Strait can seem an ironic contrast. But this little-studied world between the reefs and the rain forests is also a rich environment. A deepwater upwelling in the Molucca Sea pushes a vital plankton broth south into the ten-mile-long (16.1 kilometers) strait, and rivers running down through Sulawesi's forests also add nutrients. Whale sharks and manta rays once cruised here, but they were fished out. With those attractions gone, divers and then scientists turned their attention to the bottom, and were astounded by the profusion of life. Yet the strait can't be called pristine. The port of Bitung has nearly 145,000 people, and the heavily traveled waters gather trash. Paradoxically, this has benefits: On the strait's otherwise featureless bottom, tires, bottles, cans, and old shoes all become some creature's habitat.”

Strange Creatures of the Lembeh Strait

According to Lembeh Resort: “The Lembeh Strait is home to a host of critters which live on it’s black sand slopes and are often found hiding in plain sight. Diving in Lembeh is a muck diving bonanza with abundant species on every single dive. [Source: Lembeh Resort, lembehresort.com November 5, 2018]

“Demon Stinger (Imicus didactylus): This spooky looking critter is known by several common names including the Demon Stinger, Indian Walkman, Devil Stinger Fish and the Bearded Ghoul. The Demon Stinger is a member of the Imicus genus of venomous fishes, closely related to the true stonefishes. It is irregularly surfaced with a knobby appearance and it has numerous venomous spines to ward off enemies. This species grows up to 26cm and is red or sandy yellow with light blotches, and very similar to that of the surrounding sandy or coral seabed in which they are found. This coloration acts as a camouflage which renders them extremely difficult to detect in their natural habitat. The skin is without scales except along the lateral line, and is covered with venomous spines and wart-like glands which give it a knobby appearance. The head is flattened, depressed and concave. The eyes, mouth and nostrils project upwards and outwards from the dorsal aspect of the head.

The Demon Stinger is nocturnal and typically lies partially buried on the sea floor or on a coral head during the day, covering itself with sand and other debris to further camouflage itself. Due to the fact that this species lives a fairly sedentary life, mostly buried in sand it will often become riddled with parasites, algae and crustaceans due to the amount of time spent motionless waiting for prey. Fortunately for the Demon Stinger this isn’t much of a problem as it has the ability to shed its outer layer, effectively getting rid of any unwanted passengers! When disturbed by a diver or a potential predator, the Demon Stinger fans out its brilliantly colored pectoral and caudal fins as a warning. Once dug in, it is very reluctant to leave its hiding place. When it does move, it displays an unusual way of moving, it crawls slowly along the seabed, employing the four lower rays (two on each side) of its pectoral fins as legs. When disturbed they raise the spines along their backs and will usually move off out of harms way, however, if cornered they are able to charge at considerable speed.

“Stargazer (Uranoscopidae) are one of our favorite species to see on night dives. These are one of the most unique (and ugly) looking inhabitants of the Lembeh Strait. Stargazers are found hiding in the sand in which they are partially covered. They have top mounted eyes which peer out at you and they have a large, upward-facing mouth in a large head. Their usual habit is to bury themselves in sand, and leap upwards to ambush prey that pass overhead. Stargazers are venomous; they have two large venomous spines situated behind their opercles and above their pectoral fins. Did you know that stargazers are a delicacy in some cultures (the venom is not poisonous when eaten)? Because stargazers are ambush predators which camouflage themselves and some can deliver both venom and electric shocks, they have been called “the meanest things in creation”. In North Sulawesi the fish is often locally known as the mother-in-law fish.

“Bobbit Worm (Eunice aphroditois) is one of our most formidable critters – this nocturnal species is one of Lembeh’s highlights. The Bobbit worm buries its body into the black sand where it lays in wait for prey. Armed with sharp teeth, it is known to attack with such speed and ferocity that its prey is sometimes sliced in half. Eunicids inject a toxin into their prey, which stuns or kills it, such that prey much larger than the worm itself can be eaten and digested. The “Coral Reefs” episode of Blue Planet II shows that the Bobbit worm is capable of killing fish that are formidable predators in their own right, such as lionfish.

“ Peacock flounder (Bothus mancus), also known as the flowery flounder, this is a species of fish in the family Bothidae (lefteye flounders). The species is found widely in relatively shallow waters in the Indo–Pacific, also ranging into warmer parts of the east Pacific. The peacock flounder is also called flowery flounder because it is covered in superficially flower-like bluish spots. As suggested by the family name, lefteye flounders have both eyes on top of the left hand side of their heads. The eyes are raised up on short stumps like radar dishes, and can move in any direction independent of each other. That feature provides flounders with a wide range of view. One eye can look forward while the other looks backward at the same time. The baby flounders have one eye on each side of their bodies like ordinary fish, and swim like other fishes do, but later on, as they are becoming adult, the right eye moves to the left side, and flounders start to swim sideways, which gives them the ability to settle down flat on the bottom. The maximum length of this flounder is about 45 centimeters (18 in).

“Ribbon eel (Rhinomuraena quaesita) is also known as the leaf-nosed moray eel or bernis eel, and is a species of moray eel, the only member of the genus Rhinomuraena. What is now known as R. quaesita also includes the former R. amboinensis. R. quaesita was used for blue ribbon eels and R. amboinensis for black ribbon eels, but these are now recognized as the same species. The ribbon eel is found all around Lembeh including our House Reef. The ribbon eel is a creature bearing a resemblance to a mythical Chinese dragon with a long, thin body and high dorsal fins. The ribbon eel can easily be recognised by its expanded anterior nostrils. Based on observed colour changes, it is generally considered a protandric hermaphrodite (first male, then changing sex to female). The ribbon eel starts out at non-sexual and all black before changing to blue and yellow and becoming male. It later changes to all yellow and female. Spooky? Yes!”

Mimic Octopus

The mimic octopus is a Lembeh Strait creatures that can mimics variety of sea creatures to escape creatures that hunt it. According to marinebio.org: “This fascinating creature was discovered in 1998 off the coast of Sulawesi in Indonesia on the bottom of a muddy river mouth. For the next 2 years, scientists filmed nine different mimic octopuses, Thaumoctopus mimicus (Norman & Hochberg, 2005), impersonating sea snakes, lionfish, and flatfish—a strategy used to avoid predators. Mimic octopuses reach about 60 centimeters in length and are typically brown and white striped. [Source: marinebio.org]

“Mimic octopuses have been observed shifting between impersonations as it crosses the ocean floor to return to its burrow. Scientists speculate that additional mimic species will be found in muddy river and estuary bottoms in the tropics as these areas are typically unexplored. All octopus species are highly intelligent and change the color and texture of their skin for camouflage to avoid predators. Until the mimic octopus was discovered, however, the remarkable ability to impersonate another animal had never been observed. Norman and fellow researchers, Julian Finn of the University of Tasmania in Australia and Tom Tregenza of the University of Leeds in England, describe the mimic octopus in of the Proceedings of the Royal Society of London.

“Although mimicry is a common survival strategy in nature, certain flies assume the black and yellow stripes of bees as a warning to potential predators, the mimic octopus is the first known species to take on the characteristics of multiple species. The creatures they mimic include: 1) Sole fish: This flat, poisonous fish is imitated by the mimic octopus by building up speed through jet propulsion as it draws all of its arms together into a leaf-shaped wedge as it undulates in the manner of a swimming flat fish. 2) Lion fish: To mimic the lion fish, the octopus hovers above the ocean floor with its arms spread wide, trailing from its body to take on the appearance of the lion fish's poisonous fins. 3) Sea snakes: The mimic octopus changes color taking on the yellow and black bands of the toxic sea snake as it waves 2 arms in opposite directions in the motion of two sea snakes. Scientists believe this creature may also impersonate sand anemones, stingrays, mantis shrimp and even jellyfish.

“This animal is so intelligent that it is able to discern which dangerous sea creature to impersonate that will present the greatest threat to its current possible predator. For example, scientists observed that when the octopus was attacked by territorial damselfishes, it mimicked the banded sea snake, a known predator of damselfishes.’

Image Sources: Wikimedia Commons

Text Sources: Indonesia Tourism website ( indonesia.travel ), Indonesia government websites, UNESCO, Wikipedia, Lonely Planet guides, New York Times, Washington Post, Los Angeles Times, National Geographic, The New Yorker, Bloomberg, Reuters, Associated Press, AFP, Japan News, Yomiuri Shimbun, Compton's Encyclopedia and various books and other publications.

Updated in August 2020

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