The best diving in the world.

the best diving in the world

Indonesia by numbers… A vast country of some 17,000+ islands, strewn along 5.000kms of the equator in South-East Asia and home to more than 260 million people with about 300 distinct native ethnic groups.

A true melting pot with many unique cultures but just two seasons – warm and dry or warm and wet! The Indonesian archipelago is incredibly biodiverse and above water it is second only to Australia in the total number of endemic species that call it home.

Under the water Indonesia is considered by many to have some of the very best scuba diving in the world and diving tourism has grown rapidly over the last 20 or so years, as word spread about what there is to see. 

When Jacques-Ives Cousteau came to the region in 1989 on board his research vessel the Calypso, just one year after Gunung Api had its last eruption, he was impressed to see how hard corals had repopulated the bare seascape left after the lava flows covered a healthy coral reef. It was back then that he made the statement that “this is probabaly the best diving in the world”. 

But less well known is why the archipelago has such amazing marine biodiversity, with scientific studies identifying over 4000 fish species, compared to around 1000 in the Red Sea and 400 in the Caribbean!

The basic answer to that question is really quite simple… the eastern half of the Indonesian archipelago sits at the very epicenter of what marine biologists call the “Coral Triangle” – the region of the world with the greatest recorded marine biodiversity.

Image courtesy of Conservation International.

The Coral Triangle

Its name comes from the roughly triangular area that covers the tropical waters of the eastern parts of Indonesia and Malaysia, plus Papua New Guinea, the Philippines, the Solomon Islands and Timor-Leste.

Because of the huge area it covers, the overall biodiversity of the Coral Triangle will take marine biologists many years to fully quantify and, to date, they have concentrated on the known hotspots – but the results have been staggering!

For many years the Red Sea was considered as probably the single most biodiverse marine environment in the world, however scientific studies by both

Conservation International and The Nature Conservancy indicate that the Coral Triangle has at least four times the number of species!

But… you may be wondering quite why this fairly remote part of the world is so incredibly biodiverse and the answer is something called the Indonesian Throughflow.

Image courtesy of Journal of Geophysical Research.

The Indonesian Throughflow

Simply stated, the Indonesian Throughflow is the largest volume of flowing water in the world… So large infact that a special measurement had to be created to allow it to be quantified in a way that makes some degree of sense to non-scientists!

That measurement is called a “Sverdrup” after the Norwegian oceanographer who invented it. One Sverdrup is one million cubic meters per second – which is a lot of water in anybody’s book.

The Indonesian Throughflow is said to transport 15 Sverdrups (or 15 million cubic meters of seawater) every second – but it’s not so much the amount of seawater that holds the key to the biodiversity of the Coral Triangle, it’s what is in that water.

The Throughflow is the basic mechanism by which the eggs and larvae of the Indo-Pacific region marine life are distributed. Plus, as it passes over the deep-water basins of the region it sweeps up the nutrient rich detritus of the sea becoming the veritable life force of the Coral Triangle! 

Points of Contact

Originating in the Pacific Ocean to the north-east of the Coral Triangle, the Indonesian Throughflow is created by the Earth’s rotation and complex equatorial currents.  

It flows south-west, past the southern Philippines, towards the huge island of New Guinea where it splits, with the major portion entering the eastern half of the Indonesian archipelago. While the rest flows down the north-east coast of Papua New Guinea and on to the Solomon Islands

Where those fertile and nutrient rich waters touch land they create biodiversity hotspots. In Indonesia’s north that means Raja Ampat, Halmahera and North Sulawesi, while in the south it is Bali, the Lesser Sunda and “Forgotten” islands.

The Nymph of the Deep Seas

Enrique Rubio, the founder of our parent company is no stranger to Indonesia and has been exploring far and wide across the archipelago for many years seeing first-hand the wonderful diversity of its ecosystems.

In the late 1990’s Enrique was among the very first to recognize the potential of the traditional Indonesian Pinisi sailing ship as a motorized liveaboard dive vessel that could truly explore the waters of the archipelago.

His dream was to build a custom designed Pinisi that could take divers deep into those biodiversity hotspots to see the underwater wonders of the vast Indonesia archipelago.


In the next issue of our newsletter we will tell the full story of how SMY Ondina, the nymph of the deep seas, was built by hand in the land of the Bugis in South Sulawesi!

Want to know more about the Coral Triangle – check out this link to the dedicated site established in conjunction with Conservation International and the WWF. 

(Link: http://thecoraltriangle.com/)

Want to know more about the Indonesian Throughflow and diving in Indonesia then check out this link to the dedicated page on Don Silcock’s website  www.indopacificimages.com. Don is an Australian underwater photojournalist based in Bali and regular visitor to both our boats.

(Link: https://indopacificimages.com/indonesia/indonesian-throughflow/)