Coral re-planting project – Doberai Private island, Raja Ampat

Coral re-planting project in Raja Ampat

Have you ever thought of the importance of corals or coral reefs affection to humanity? Has the coral reef, as a word, been just a distant thing that your neighbor has been telling you excitedly about after his trip to Thailand? Although most of the world’s coral reefs are located near equator, their well-being have an impact to all people in the world. In addition to the fact that more than 500 million people around the world are dependent on coral reefs for either food or livelihood, reef organisms have also provided cures to treat asthma, arthritis and certain cancers. So welcome to a little exploration of the most interesting place in our seas and to see how our coral re-planting project here at Raja Ampat actually went.

Coral re-planting project

As I told you in the beginning, it is probably obvious why we feel that the well-being of coral reefs around the equator is important to us. In fact, the well-being of coral reefs is so important to us here in West Papua, that as soon as we heard the coronavirus will shut down the resort for months, we decided to start our own coral reef recovery project. We got inspired by one of our diving instructors who did a similar project in Java, Indonesia. It should be noted that there are many ways to grow corals. Different technigues are constantly being developed to help with coral planting and it has been great to get to know different ways to do this. This method of ours is very traditional and does not involve any kind of new innovations, microfragmenting or electronic radiation.

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What is coral and coral reef?
There are many types of corals and they belong to the animal kingdom, more specifically to the cnidarians. Rock corals and soft corals differ in appearance but also in structure. In this story we take a look more closely to rock corals as they largely form coral reefs. Rock corals are made up of lime frame bodies, polyps that are attached to them and zooxanthellaes which are living in them symbiotically. Most corals are communities of thousands of polyps, and the coral polyps that make up the reef survive by forming a symbiotic relationship with zooxanthellae algae. Corals provide algae protection as well as nutrients, while zooxanthellae provides coral energy, oxygen and food in exchange.


koralliprojekti7Like other amphibians, coral polyps are made of two cell layers: the outer shell (the ectoderm), and the inner layer (the entoderm).
They are surrounded by the sac-like hollow belly. Between the two cell layers there is a mesoglea called medium, which in loose cells drift and the outer
edge of the oral cavity which is bordered by a mouthpiece.


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Rock corals mouth is surrounded with trapping tentacles. A coral polyp animal catches plankton from the water with its tentacles and feeds coral animals mainly with plankton. However, some corals prey on invertebrates and small fish with gill cells. Many rock corals defend their habitat aggressively and when another species gets too close, they can grow combat tentacles that are up to five times longer than normal trapping tentacles.
The growth of corals which are the same species, may accelerate when pieces taken from the same family are planted close together. Microfragmenting is one of the latest innovations in coral cultivation, where the idea is to break up one piece of coral into the smallest possible pieces. The pieces are then placed close together to grow, allowing them to gain strength from each other and grow faster.


Rock corals can reproduce either by asexual division by cloning themselves or by sexually releasing their eggs into the water once a year. A coral reef is formed when several rock corals split on the seabed, building a cohesive structure. This is how the new coral reef in Doberai will be created artificially.

koralliprojekti4Coral re-planting project


The importance of corals to the world
Coral reefs are often compared to ocean rainforests and lungs. Corals absorb carbon dioxide from the atmosphere and convert it into respirable oxygen. In this way, they regulate the air and water temperature for all of us. Coral reefs are vital to marine biodiversity and are spread to 250,000 square kilometer area. Although they cover only 0.1% of the world’s seas, they still provide a home for up to 4,000 fish species, 800 coral species and thousands of other plant and animal forms.
In addition to all this, corals protect the coasts from elapse and erosion. They also reduce the damage caused by hurricanes and tsunamis.

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What threatens coral reefs?
One of the biggest threats to corals is certainly climate change. As a result of climate change, sea levels are rising and waters are warming. When the water overheats, the corals become stressed and expel the zooxanthellae algae that live in symbiosis. And because corals get most of the nutrients they need from algaes, over time without them, corals will wither and fade. In many countries corals are threatened for example by overfishing or fishing with dynamite. Indonesia is one of those infamous countrys that has used very questionable fishing methods for years. The next threat of course, will be non-biodegradable waste, chemical waste, and in some cases tourism. It has been predicted that if the world continues in the same pattern, by 2050 all the corals in the world would be dead.

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With small daily things during our holidays we can contribute to the well-being of the seas during our holidays. Among of other things, the sunscreens we use should also be ecological just to protect corals.
Now that we’ve iterate a little bit of general thing about the world’s corals, their biology and talked about the threats, we can move on to the real thing, our coral re-planting project.

Coral re-plantating projectCoral re-planting project

Starting a project and its early days
Because the coronavirus was already spreading around the world and there was no way to order anything, the first part of the project was to find out the available materials needed for the project. Would we have any material from our own to build the base to the reef, what we could use for attaching it and what else would the project require? Because of the unstable situation in the world, it was out of the question to even try to order any materials for the project from anywhere. We had to get along with the materials that were available from the nearby village of Waisai. It was sad to notice afterwards, that by ordering for example ecological glue, we would have been able to make this project much more environmentally friendly. While doing this project i learned from Finnish-owned Fast Manta diving company in Thailand that they did a similar project in Ao Nang by using wound care glue to attach corals. Well maybe next we can also try that!

In addition to the materials, we also had to think carefully about a suitable location for the coral reef. Where around the island would be the best, brightest and most sheltered place for a new reef? So we spent a few days in the ocean just observing the currents, tides and other corals around. To survive, the coral needs a shallow place at a depth of about 2-3 meters, sunlight, clean / clear water, a temperature of 20-32 ° and of course salt water.

RajaAmpat_lockdown (2)Corals grow best in shallow water, allowing sunlight to reach the corals. Different coral species living in different areas can withstand different temperature changes,
but in general corals live in an environment of 20–32 °. Clean water is also absolutely essential for the reef,
and for example wastewater discharged too close, may contain too many nutrients that cause seaweed.

We found quite easily few good places in front of Doberai Island where we could build a new coral reef. The place we found perfect to our new coral reef had have a few unfortunate things which led to the partial destruction. In addition to boat traffic and local fishing, one of the most effective destroyers here has been the Crown of thorns starfish. The crowned crown is a large, toxic starfish species found in Indopacific marine areas. It eats live coral and spreads really fast. During the corona, we have collected several dozen of them from the sea and we inspect the reefs evenly for them.

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koralliprojekti16Crown of thorns starfishes are collected from the corals with a long stick and slipped into a bag. The Crown of thorns starfishes can be disposed of either by burning or just by burying to the ground.

toinenviikko_2 (1 of 1)For the reef base structure, we wanted to use cages found on the other side of the island that had once been abandoned by pearl farmers.


koralliprojekti14Cages have been lying on the seabed for ten years. Cleaning them from algae is a time consuming work.

Once the cages had been collected as well as cleaned, it was time to take them back to the sea in new places. In order for the coral reef structure to be stable in the seabed, we had to fill the cages with dozens of rocks.


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The cages quickly found their new places on the seabed and loose stones found on the bottom were used to stabilize them.

RajaAmpat_2020 (5)The first cages were randomly placed on the bottom. 62 corals were placed in these cages.

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At a later stage, we got so excited about this project that we decided to do the whole project again. The next location was selected to be a slightly flatter terrain from the seabed and resort name DOBERAI was written from the cages to the bottom.

At the same time, on the surface, some of us made the cement substrates of suitable size and shape for the coral pieces. After a few days of drying, the substrates were immersed in the sea to collect plankton as well as bacteria. This will make it easier for corals to adapt to their new growth base.

Coral re-plantating project

Coral re-planting projectAriep made a small hollow for corals to each substrate and holes in the sides for attachment to the cages.

Next, it was our turn to find suitable corals. The rock coral we set out to find and grow is called Acropora branching. Acropora branching is a rock coral specie that is one of the most common coral on coral reefs. The corals to be replanted can be either living pieces that have already detached from the coral reef or small pieces carefully removed from the larger coral. It has been studied that cuttings taken from large colonies are not detrimental to the parent colony. It has been noticed that just in few weeks, the surgical site begins to grow new fresh tissue to replace the cut one. We collected loose pieces as well as cuttings from our home reef and a little bit further away from next island called Gam.


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We attached the corals piece by piece to the substrate with cement. Live coral should only be on the surface for a short time, so this operation had to be done quickly. We stored the coral pieces in a container filled with seawater and quickly attached coral into the substrate. One of us made a small mound of cement to the platform, one attached the coral and third was ready to take them back into the ocean.

Coral re-planting project

Coral re-planting project

Once each coral was successfully planted in the substrate we left them in a sheltered location next to our pier for quarantine. Quarantine and observation time is an important part of the project, because during that time we can first see whether each coral survives and whether new corals carry any diseases. Our first batch was quarantined for less than a week, but the next batch we kept in isolation for 10 days. After quarantine time, both coral batches were alive and ready to take deeper into the ocean.

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After this, the corals were ready for the next stage, to move to their new home. We first transferred the corals in water containers to the ship, from where they were carefully lowered to the ocean by using cages. Three of us were waiting at the seabed for newcomers and ready to attach them to the platforms. If the intention is to plant corals from different families, then it is very important to remember to set proper safety distances for them. As I mentioned at the beginning of the text, some coral species defend their living space aggressively, and when an individual of another species gets too close they can grow their combat tentacles and attack.

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RajaAmpat_2020 (2)Coral re-planting project



_korallinkiinnitus2We tie the coral bases to the cages with cable ties that we cut as small as possible. Glue could also be used very well at this point if it were available.

RajaAmpat_6viikko (15)Coral re-planting project


Coral re-planting projectCoral re-planting project


Coral re-planting projectCoral re-planting project


koralliprojekti2Word DOBERAI written down!

Then begins the hardest part of the project, waiting! Coral grows about 2 to 10 cm per year, depending of the coral. Ariep said that in a project in Java, their Acropora Branching corals grew up to 13cm a year! In order for us to have a completely new, whole and big coral reef here, it will take several years. Even if the growth is small, the rock corals are still able to spread quickly and grow the reef efficiently. As I mentioned at the beginning, rock corals can multiply by cloning as well as spreading eggs.

Coral re-planting projectWaiting and observing the environment.

One nasty guest on the coral reefs is a parrotfish that uses its teeth to bite corals. Parrotfish got its name for its colorful appearance but also because of the mouth that resembles a bird’s beak, which it uses to access the inside of the coral it has eaten. Some species beat their heads on the reef until large lumps come out of it.

Coral re-plantating project

Raja Ampat
Although Raja Ampat region is still one of the richest coral regions in the world, that still does not mean that it is not worth to put an effort to the reefs right here. Hidden from mass tourism, Raja Ampat is one of the most beautiful and unique travel destinations in Indonesia. Among divers, Raja Ampat is considered one of the best dive sites and travelers should not miss underwater life.
Raja Ampat is one of the richest coral areas in the world, with over 500 species of different corals in the area. More than 1,300 species of fish swim in the waters of Raja Ampat and the most majestic are wobbegongs, devil rays and dugongs.



Project progress
Below this I will update the pictures of the progress of the project and the growth of the corals.

APRIL 2020
The first batch of 62 corals
– 6th of april 2020 Planting on the seabed.
– 16th of april 2020 16 dead from either parrot attack or currents.
– 30th of april 2020 no new dead corals. 10 new corals will be planted to replace those that have already died.

Another batch of 100 corals
– 30th of april 2020 Planting on the seabed.

Coral re-plantating project
APRIL 2021

Checking after one year our Coral Garden the results are amazing! There has been few losses during this pandemic, since there has not been anyone to look after coral baby’s. But still happily I can say that from 162 re-plantation corals there has been only around 50 dead ones.




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