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Giant Clams of Sabah

giant clam

Out of 9 species of giant clams (Kima Gergasi) in the world, Sabah has 7. Namely (number in bracket is the adult size of each species):-
1. Tridacna gigas (1.5M)
2. Tridacna derasa (40cm)
3. Tridacna squamosa (30cm)
4. Tridacna maxima (20cm)
5. Tridacna crocea (15cm)
6. Hipoppus porcelanus (40cm)
7. Hipoppus hipoppus (30cm)

Don’t be so happy yet. Due to overfishing, the two largest species, Tridacna gigas and Tridacna derasa, are now considered critically endangered in Sabah (some say they are locally extinct). All species of giant clams are listed in “Convention on International Trade in Endangered Species of Wild Fauna and Flora” (CITES), which means they are endangered and should be protected.

Tridacna gigas
Above: Tridacna gigas, the largest species of giant clam, can reach 2 M in length, weigh over 200 KG, and live to more than 100 years old! But sorry, locally extinct already.

Tridacna derasa
Above: Tridacna derasa, also a locally extinct species. Very rare in the wild.

Tridacna squamosa
Above: Tridacna squamosa species

Tridacna maxima
Above: Tridacna maxima species

Hipoppus porcelanus
Above: Tridacna squamosa species

Giant clams live like a plant, as their main diet is organic nutrients which come from the photosynthesis of millions of symbiotic algae (zooxanthellae) that live inside their mantle. In return, giant clams offer the algae a safe home.

Harvesting, trading and buying of giant clams are prohibited under the Malaysian Law. However, enforcement is different story. Just went to tamu (native market) in Kota Belud and see it yourselves. The hawkers sell and slaughter the giant clams openly. They don’t feel anything wrong about it, and didn’t even bother when I was photographing them.

Giant clams for sale

Above: see the yellow and red boxes and two big white sacks behind the seller? They are all giant claim shells! There were many happy buyers and many giant clams were sold in just a few minutes.

Giant clams for sale
Poor giant clams. They may have taken more than 3 years to grow to these sizes. They are eaten before they are mature enough to breed.

Giant clams for sale
Giant clams live in shallow lagoons, reef flats, and the sandy and rubbly substrate of coral reefs in the tropical Indo West Pacific.

Giant clams for sale
Giant clams were once everywhere. Now they are getting rare because human eats their meat. Humans are the worst predators of giant clams.

Giant clams for sale
Giant clams do not get enough attention like sharks and turtles, though they are one of the most fascinating marine creatures.

Giant clams for sale
Giant clams also uses a siphon to draw in water to filter and consume plankton. By absorbing and filtering nitrates, ammonia and other organics that are harmful to coral reefs, giant clams help to clean the water in marine ecosystems.

Giant clams for sale
These giant clams were slaughtered for their meat and sold for RM5 (small) or RM8 (big) each.

Giant clams for sale
Above: giant clams waited to be slaughtered alive. Business was good and they were unlikely to survive until sunset.

I also went to Gaya Street Sunday Market on the same day. More than 100 giant clam shells were sold as handicraft items such as soap dishes, ash trays, shell lamps and ornaments.
Giant clams in Gaya Street

There were tourists buying giant clams. Under the regulations of CITES, giant clams, whether dead or alive, cannot be carried out of our country. I don’t blame the tourists don’t know they are sponsoring an illegal trade. But what the heck is happening to our authorities (Fishery and Wildlife Departments)? Are they blind?

Tourist buying Giant clam

Below: a big giant clam shell is sold for RM25 (about USD7.50).

Giant clam for RM25

More photos of giant clams sales in Gaya Street… It seems like giant clam trade has become an “industry”. It is very hard to find the whole complete set of giant clam shells on the beach, so very likely these shells were taken from live giant clams.

Giant clams in Gaya Street

Giant clams in Gaya Street

Giant clams in Gaya Street

Giant clams in Gaya Street

So you think that the problem is not serious enough? Just take a walk in dried seafood market nearby. You will see giant clams (as dried seafood) everywhere.

Giant clams as scallop
The most valuable part of giant clam is its adductor muscle, which is commonly sold as scallops, which cost over RM100 for a small pack in dried seafood markets.

Giant clams as scallop
Overfishing of giant clams is a serious problem, as they are considered as a delicacy and profitable seafood. Besides overharvesting, climate change and pollution are also factors that speed up the extinction of giant clams. Excessive CO2 from atmosphere makes the sea water more acidic and lessens the ability of giant clams to grow their shells. The rise in sea temperature will also disturb the symbiotic relationship between the clams and the zooxanthellae that nourishes them. The introduction of a coal power plant in Darvel Bay, which is located inside the Coral Triangle, would pose a threat to giant clams.

More giant clam handicraft items sold in handicraft market… My heart is broken.. FYI, giant clam in movies is always portrayed as a man-eater because it snaps swimmers’ legs by surprise and drowns them. Actually this is impossible. First, you have to find a really huge giant clam, which is extremely rare. Second, giant clams close very slowly and most do not close completely. They do not snap. They are not monsters ok.

Giant clams in Handicraft Market

Giant clams in Handicraft Market

Giant clams handicraft

Currently Sabah has two places that spawn and propagate giant clams and you can see all 7 species of giant clams in their sites. The first one is Marine & Ecology Research Centre (MERC) in Gayana Eco Resort of Gaya Island, and another one is Sabah Parks Hatchery at Bohey Dulang Island (see photo below) in Tun Sakaran Marine Park off Semporna. This hatchery was built in year 2004 and fully operational with a completed laboratory in 2009.

Bohey Dulang Hatchery

To start, the giant clams will be induced (by temperature or injection of chemical) to release their eggs and sperms for fertilisation. The eggs will be collected. A week later, the larva of giant clams will settle and find a spot to grow, then they are moved to settlement tanks.

Settlemnt tank in Bohey Dulang Hatchery

The giant clam larva will spend half a year to grow up to 3 cm. Then they will be released to the sea inside a cage (to protect them from predators), until they grow to 9cm or more after a few months. At last, they will be released independently to the ocean bottom without a cage. Less than 10% of the eggs will survive at the end.

Baby giant clams

T. gigas and T. derasa have the fastest growth rate. They may reach up to 9-12cm after a year. The suitable release spot will be clean and well-illuminated sea about 10 feet in depth or less with mild water current. Giant clams reach maturity very late, at about 7 to 8 years old.

Bohey Dulang Hatchery

Bohey Dulang Hatchery Station has a mini exhibition hall and a settlement tank area, which are open for public to visit. You can see at least 5 species of big giant clams in their display tank, great for an education tour. To visit the islands of Tun Sakaran Marine Park, you need to get a permit from Sabah Parks first.

Beautiful giant clams in fish tank

However, no matter how hard and how long these two centres try, they are only able to increase the population of giant clams in limited scale, not the whole ocean around Sabah. The conservation has to be started from you, the consumers. Just don’t eat and buy any giant clam product and the killing will stop. Eating giant clams is as bad as eating shark fin and turtle eggs. The key obstacle of all conservation efforts in Malaysia is the mentality of “if I don’t kill them, others will”, a selfish excuse for greedy mouth of Malaysians. Well, that’s why our country is so dirty, as everyone thinks, “if I don’t throw rubbish, others will.” Anyway, if I can make only one of you to stop consuming giant clam, this blog already worths my time and efforts.

Photos taken in Kota Kinabalu & Semporna, Sabah Malaysia

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Marine Ecology Research Centre (Gayana Resort)

Many years ago, I went to “pulau” (island) a lot with my father who owned a boat that time. I can tell you that Sapi and Manukan Islands today are NOTHING compared to their past. There were so many (and dense) beautiful corals that I could even see them from the beach. After more and more tourists flow in, now the corals don’t stand a chance to grow near the shore when so many people step on them every day.

Gayana Resort

That’s why I like what Gayana Resort (of Gaya Island) is doing now. Not only their restaurant has removed shark fin from their seafood menu, they also put a lot of efforts on conservation and being environmental friendly, so their business won’t impact the surrounding environment negatively. When they take, they also give – what we call responsible tourism. Besides recycling the waste, this eco-resort also replants the corals at Gaya Island.

Gayana Resort

Their Marine Ecology Research Centre (MERC) is an education and aquarium centre worth checking out. It has some display of live hard and soft corals and giant clams, which they also try to cultivate and release to the sea. Their staffs are also very knowledgeable and introduce us the cuttlefish that can change colors, pretty bamboo sharks and other interesting sea life.

Giant Clam

The centre claims to have 7 out of 8 species of giant clams in the world. Giant clam is very sensitive to pollution and grows very slow. Even after 10 years, its size still can be smaller than a fist. Their population is declining fast and listed as protected species, though many fishermen don’t care and still eating them.

Giant Clam

They label each coral and clam with number, for their coral and clam restoration programme, so the tourists, who release them, can come back and visit their “baby” years later. Last time I had very bad impression about MERC coz the previous management seemed like never cleaned the fish tanks. They improve a lot after the new management took over.

Marine Ecology Research Centre

There is a tank with two turtles. They were excited to see people and came to us. I am not sure if they want to play with me or bite me. Below is a photo of hawsbill turtle at the front and green turtle behind, both are endangered species. This hawksbill turtle was sick and was rescued from the hands of children who played with it on the beach. It is doing well and looks healthy after treatment by UMS (University Malaysia Sabah).

Hawsbill and Green Turtles

Below is a photo of green turtle that “smiled” at my camera. Many of them are killed by swallowing plastic bags that look like tasty jelly fish to them. And also a lot of them are trapped and died inside the net of fishing boats every day.

The government sector needs to work harder. Fish bombing still happens even in marine park as close as Sapi. Many scuba divers will tell you that they hear it and there are less and less fish species in Tunku Abdul Rahman Park. I also hear a lot of stories about the corrupted marine police (at east coast) who disregard fish bombing and more interested in constantly harassing the fishermen by taking away their caught. Turtle eggs are still readily available at the market if you know how to signal that you want to buy.

Green Turtle

Sorry that I don’t have a lot of photos to show coz I stayed there only for a short while. BTW, Gayana Resort has RM68++ dim sum buffet promotion (include transfer to/from Gaya Island and free visit to MERC) during Chinese New Year (Jan 26,27 and 31 if I am not mistaken). FYI only, I don’t work for them. I let you know coz I think it is better than buying the RM100 BBQ lunch package of other island trip (I read the reviews that their food taste like sh*t for that price).

Photos taken in Gaya Island, Sabah, Malaysia Borneo

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