Why (the heck) did I study giant clams?

Happy Lunar New Year everyone! In the spirit of this festive season, the young ones in the family often get asked/questioned about their life stage (or some may say crisis!), such as ‘are you still studying’, ‘are you seeing anyone’, ‘when are you getting married’, and (hopefully finally!) ‘when are you going to start a family’. 😛


On a similar note but on my career path, I noticed that the questions I get these days have somewhat ‘transformed’ over the years. I remembered in the earlier years of my career, I typically talked about my scientific research, but nowadays people are curious about my life choices. So here are some examples of questions I get from all walks of life…

“What drew you to marine biology?”

“Who or what motivated you to go into your field of study?”

“How did you become passionate about marine biology, in particular getting fascinated with the giant clams?”

“What led you to study giant clams? What is it about them that fascinates you?”

“What is your motivation behind saving these gentle beasts?”

“So why giant clams?”

“Do you often get asked about why you’re doing this?”

Yes, (very) often, I get asked about what motivates me to choose this path, and how did I arrive at where I am today. Even until today, my family and friends still wonder why I chose to work in the area of marine research and conservation, although my choice of work is not surprising for me. So I decided to pen my personal story here to serve as both a reminder and resource for anyone who is interested to become a marine biologist in Singapore! I’m geographically limited because most of my educational background is from Singapore. So here we go!

My youth fascination with the natural world…

As a young child growing up in urban Singapore, I have always been fascinated and curious about the natural world. My parents would take my sibling and I to various outdoor places during the weekends, exploring every nook and cranny of Singapore. My most fond memories of my childhood included taking my plant book on car rides and pointing out the trees I see along the roadside. Yes, I used to love plants! 🙂

I never thought about becoming a marine biologist as a child, but the chance had only came through when I was older and curious…

Marine biology research and the marine station in Singapore…

This was taken when I was starting out as a student researcher in 2007/2008.

As to how I chose marine biology, it was when I first visited our marine station based on St John’s Island. [Note: The facility is now known as the St John’s Island National Marine Laboratory.] For a city girl, it was a first for me to physically interact with actual living marine life in the lab and meeting local marine biologists working on them. When I was shown the outdoor aquarium tanks, my first thought was “Wow, we have marine life right here in Singapore!” For the very first time, I saw live hard corals, baby giant clams, seaweeds, and everything marine – amazing! Not forgetting meeting up with the REAL marine biologists working at the laboratory, who shared with me their research, as well as their love for the marine world.

TMSI Colleagues
My fellow colleagues working at the Tropical Marine Science Institute.

That first-hand experience became a life-decision to pursue marine science research. I had eventually overcame my mild claustrophobia, and took up diving lessons so that I can be closer to marine biodiversity. The more I had explored this amazing marine environment, the more committed I am to studying and protecting these fragile ecosystems. Eventually, the years of researching on the giant clams had paved my dedication to conserving the endangered giant clams from extinction in Singapore.

Sandy the cat
The friendly neighbourhood cat, Sandy on St John’s Island.

[Quick note: I studied my Bachelor’s degree in Life Sciences (NUS) and focused on Biology. We do not have a degree for marine biology, and it’s through a few module courses that I got to learn about the fundamentals of the subject. I continued to do my PhD degree in Science (NUS), although I would include a description that I focused on Marine Ecology.]

Giant clams were my only option then… (hehe!)

I always giggle to myself when I get the question on ‘How did you choose the giant clams?’ and ‘Why them and not others?’ The backstory to how I ‘chose’ to work on the giant clams was not typical or ‘love at first sight’. My interest with the giant clams did not begin immediately, but developed over time during my university days. I had wanted to find out what biodiversity research was about, and the giant clam project was the only project available for sign-up! Lucky for me, even though I was neither a diver nor had any marine biology field experience, I was fortunate that my supervisor still took me in as his student.

When I first started out, I got hooked on experimental marine science research – I had so much fun setting up my experiments (and being obsessive about how I arranged my beakers, tanks, and rulers in neat rows and columns). My experiential learning through failures had not only motivated me to persevere and see through my projects, I had learnt to appreciate that I cannot control my animals’ behaviour! They simply do anything they want! For one of my experiments, I had to think of a contraption that prevents the baby clams from walking out of the beakers and out of my treatments!

Giant clam
Illustration of my model species, the fluted giant clam, Tridacna squamosa. By Loy X. from Wild Drawings.

With the giant clams, it’s very hard to not like them! Giant clams have to be one of the most fascinating groups of marine creatures. They are the world’s largest shellfish, where the biggest ones can grow to measure a meter long and weigh over 300 kilos – heavier than a baby elephant! They’re so big that people used to believe they were man-eaters! Some studies thought that giant clams could live to be 100 years old. These colourful clams are also ecologically essential to coral reefs.

Legends tell of a man whose legs were lost to a giant clam! (By Kenneth CHIN)

Their biology and behaviour absolutely (and continues to) fascinate me – from how some of them can bear large pearls to how they can ‘see’ us, and the adorable baby clams that we culture at our marine facility! And as my research on giant clams progresses (and this is mainly from reading more of the literature and going for field trips), I saw how conservation efforts often need to be supported by sound scientific research. Since then, I have used different avenues to share our research and communicate scientific knowledge to public masses via blogging platforms and volunteering stints.

I want to make a difference for the environment…

For as long as I can remember my love for the environment, I have a life motto: “I believe in making a contribution, no matter how small it may be, as that small effort will help make a big difference to the environment.

10-year road map
In my early days of career, I started to mapping my research roadmap for the next 10 years, and 4 years has since passed…

Before I knew I was going to be a scientist, I understood the problems of pollution and deforestation. I started with just using less paper, recycling my completed homework, and generally try to be ‘environmentally-friendly’. Although I must say that I may not have been aware if I am being friendly to the environment or not!

After I became a scientist/marine biologist, my goals have shifted towards contributing scientific knowledge that I hope will be helpful – in my case, towards species conservation. More recently, I am focused on using science communication to engage with the public.

Generally, I know that I am a highly-driven, independent, and hardworking person. When I set out to do something, I will somehow see through it, regardless if the impact may be big or small. I do agree that it would require a certain tenacity and the ‘never say die’ attitude to get past the many challenges and obstacles in front of me. Plus, I had a wonderful support network of friends, colleagues, and eventually, my family behind me all these while… If one component was missing or lacking, my career path would surely have been even tougher!


If you had asked me these same question 5 years ago, my response would be ‘Aiya, my story isn’t that interesting. Why do you want to know?’ In my later years of career, as paiseh (embarrassed) as I am to talk about my career journey, I am heartened to hear that my stories have resonated with people and that my stories have made them feel ‘better about themselves’. Personal journeys and stories are what make us more human and down-to-earth, relatable and less intimidating. Like others, I have my fair share of struggles before reaping the fruits of success. Like others, I cry, whine, and get angry, but I’ve learnt to embrace my faults and become a (slightly) better person.

Through my sharing, I hope that you can relate to my journey on achieving my dreams.


Publication Alert! – Managing giant clams in the South China Sea

I am so proud to see this work finally published and in-print! This is one of my first few research collaborations when I was starting out my post-doc career in 2014. It is also a meaningful paper (and I hope it won’t be my last!) that merges the brains of environmental lawyers and a marine biologist to synergise on the information we have from our respective work and put it to good use by making arguments for using existing ocean laws to protect endangered species in the South China Sea. This is also how I got interested in understanding the various ocean laws that govern the boundaries of the open seas, and how scientific research and baselines can be used to support the application of marine environmental laws! 🙂

You can read the Abstract of our new paper below:

Lyons et al. 2018-01

What is the premise of the paper?

It is stemmed from the widespread harvesting of fossilised giant clam shells in the South China Sea. You can read more about it at The Story of Shells Part 1 and 2.

What did we suggest?

Okay, this may get a little technical, but here’s the gist: we made recommendations based on scientific evidence such as life history of the giant clams, reproductive strategy, and the vulnerability of populations in the South China Sea. On the basis that all of the scientific evidence points to the species being endangered, we highlighted numerous Obligations that nations should adopt as they are all Parties to the United Nations Convention on the Law of the Sea (UNCLOS). These Obligations are already listed in UNCLOS, and the paper highlights how each Obligation is relevant to the case study based on science! Here are the four main Obligations:

  1. Obligation to protect and preserve the marine environment
  2. Obligation to protect threatened and endangered species and their habitats
  3. Obligation to consult and cooperate
  4. Obligation to protect and preserve species under CITES

Another motivation that we had wanted to address in this paper is that the South China Sea is a geopolitically sensitive region, and recommendations such as demarcation of boundaries would not work so easily due to conflict of interests from neighbouring countries. Instead, we proposed alternative application of UNCLOS to get the States to cooperate through their Obligations to the Convention as Parties.

What is next?

So, publishing our argument is one thing, but how can we actually apply this? First, we need to disseminate the paper and information to the relevant people and authorities. So yes, accessibility to the paper is my first step! I will think about the rest when the time comes… 😉

If you would like a copy of this paper, please let me know and I am happy to send it to you. 🙂

Tanmen - 21
Tridacna gigas shells found in a factory located in Tanmen Village, Hainan Island, China.

What’s in the Lab?

From casual conversations, I get the impression that people’s perceptions of becoming marine biologist are that you need to be passionate on a topic or an animal, or be very field-capable. Hmm – that’s not entirely true! When I first approached my supervisor to do a marine biology project, I was neither a SCUBA diver nor do I have any relevant experience and knowledge on marine biology! But I did know that I wanted to ‘try’ being a marine biologist for the duration of my project. And well, the rest is history… 🙂

My early research comprised mainly experiments in tanks and the other big component of my work is desk-based literature reviews. You may not realise now but literature review is a HUGE part of research. It is where you learn to glean information on the topics, animals, ecological processes, etc…, as well as ask questions and develop hypotheses. Literature reviews also appear in the Introductions of many publications to provide the basis of studies and surveys. In a sense, such reviews stimulate research questions and curiosity for marine science.

Just like Sherlock Holmes, the famous detective who solves murder mysteries, I too ‘hunt down’ clues to get answers. The main difference is that I use the information to help connect the dots to modern-day natural history. And the best parts about literature reviews are the (unforetold) stories that come out of it! 🙂

To give you an example, I was working on the stories of the giant clam shells in China over two parts: Part 1 and Part 2. In order to present a balanced view, I made sure to refer to both English-based and Chinese-based media reports to extract information to support my story-telling. This Chinese article (below) is one of those gems I found, but alas, I am blocked from re-entering the website – haha! Fortunately, I screen captured it and it is presented herein. The article mentions the historical background of giant clams in ancient China, and highlights the fluctuating value of this resource. See my brief translation after each section of the article.

Headline: One piece of giant clam in ancient China is actually equivalent to 10 plots of farm land? From shell currency to today’s giant clam. The original article was published on kknews.cn.
Everyone knows what is a giant clam, and its name was derived since the Han Dynasty. Because of its shell patterns (looking as though the wheels passes through drains, and similar to car tracks), hence they were named Che Qu. And because the shells are hard, the Chinese characters for Che Qu has the word stone in them. In the history, giant clam played many important roles, but they are best known for being most value for money.
In ancient China, giant clams are recognised as a priceless treasure. There was a story recorded in the Shang Shu Da Chuan, where the King Zhou Wen’s random was paid using giant clams. Also in the Qing Dynasty, the second grade officials wore beads made out of giant clams. In the Tibetan secret religion, the high priests Lama used prayer beads made with giant clam shells.
We know that neither transportation was convenient nor technology was advanced in ancient times, so seashells are a very precious resource, thus useful as a long-term currency. Towards the end of Xia Dynasty, shells became a currency exchange media. In businesses, a type of ‘toothed’ seashells were used in transactions and called Huo Bei. So, what is the value of the largest shell – giant clams – worth in ancient times? Below, we will share with everyone the validation. As the value and worth of seashells vary between different historical periods, we chose the more stable rates as the rough estimation of giant clams’ value.
In brief: Cowries were commonly used as currency media. It is said that 40-80 shell currency could buy one plot of farm land.
Note that the seashell currency in the image consist of smaller pieces, which are less valued compared to whole pieces of giant clam shells (almost 100-500x more, and because of the rarity of transporting whole shells). It was estimated that a single complete giant clam shell was worth 200-1000 shell currency, and could buy 5-10 plots of farmlands! In fact, giant clams came up as a shell currency but not well-established as a major currency yet. Its pricelessness was recounted in the stories of being used to pay the random to save King Zhou Wen.
By the Qin-Han Dynasty, modes of transportation improved and shell currency was slowly phased out, thus the value of giant clams and other seashells dropped. At the same time, the immersion of Buddhism quickly raised the value of giant clams again, as one of the 7 treasures of Buddhism, and it became popular amongst the Buddhist followers.
By the Qing Dynasty, the value of giant clams peaked once again. It was used to distinguish the ranks of their officials and used as one of the gems for their attires. It was assumed that the value of giant clams versus crystals were comparable then. Approximately 300 RMB could buy 2-5 g of crystals, which tells the similar value for giant clams.

Lastly, here are some examples of the literature reviews that I’m very proud of, and one of which took a grand total of 3 years to complete! These papers are all OpenAccess and that means you can download them for FREE at these links.

  • Neo, ML, CCC Wabnitz, RD Braley, GA Heslinga, C Fauvelot, S Van Wynsberge, S Andréfouët, C Waters, AS-H Tan, ED Gomez, MJ Costello & PA Todd (2017) Chapter 4. Giant clams (Bivalvia: Cardiidae: Tridacninae): A comprehensive update of species and their distribution, current threats and conservation status. Oceanography and Marine Biology: An Annual Review, Volume 55. Pp. 87-388.
  • Neo, ML, W Eckman, K Vicentuan-Cabaitan, SL-M Teo & PA Todd (2015) The ecological significance of giant clams in coral reef ecosystems. Biological Conservation181: 111–123.
  • Neo, ML (2012) A review of three alien parrots in Singapore. Nature in Singapore 5: 241–248.
  • Neo, ML & PA Todd (2012) Giant clams (Mollusca: Bivalvia: Tridacninae) in Singapore: History, Research and Conservation. Raffles Bulletin of Zoology 25: 67–78.

The Story of Shells – Part 2

Disclaimer: Opinions are mine.

Satellite imagery between 2012 and 2015 had led to the exposé of widespread dredging of fossilised giant clam shells in the South China Sea. The distinct arc shapes, visible from space, were the result of boats chopping along the reefs. What was even more surprising is that this was done to reveal the buried giant clam shells!


My curiosity brought me to Tanmen Village, and I shared my story through a photo-essay earlier this month, and published it here. Now that you have seen the industry through my eyes, I wanted to provide the contextual insights of the Chinese cultural history, industry and how businesses have bloomed since the introduction of giant clam shells as materials.

Advisory: This is a 15 min read.

1. Significance of Giant Clams (硨磲贝) in Chinese’s cultures

Culture or ‘the way of life’ usually plays a big role in influencing people’s habits and mindsets. Whether they are a fisherman, a craftsman, a farmer, or a religious priest, their actions are mostly driven by their cultural beliefs and hand-me-down stories. It was a similar situation for the giant clams and the Chinese’s lifestyle.

During my walkabouts in Tanmen Village, I’ve learnt several interesting details on what the Chinese thought of the giant clams:

  • Giant clams are one of  China’s treasures
  • Considered a rare organic gem (有机宝石) that is produced by animals – the purest of white ‘jade’
  • At times, they are referred to as the ‘jades of the sea’
  • Has been mentioned as one of the seven treasures in Buddhism
  • Believed that it can help ward off evil and protect the health of families based on its supposed healing properties
  • People are aware that giant clams are nationally protected species (国家一级保护动物), thus making them even more highly valuable!

Okay, so my initial conclusion was that this appears to be one of the typical beliefs that the animals had special properties to aid with health issues (something like the rhino’s horn, tiger’s penises, and seahorses). And the other facts were to stimulate the demands and sale of giant clams in China – a marketing strategy.

Or so, I thought! Later in my exploration of the shops, I found this book entitled “National Treasures – Giant Clams” by Li Heng, a Hainanese-based writer whose interests is to promote the cultural heritage of Hainan Island. On the front cover, it also says that this book is the first of its kind to discuss extensively on giant clams in China.

THIS WAS A TREASURE FOR ME! Imagine my excitement when I ‘accidentally’ came across this book! I was glad that I’ve left no stones unturned, and what I read what absolutely compelling. 😀


It seems like the giant clams go wayyyyyyy back in Ancient China (most conclusively present in the Qing Dynasty)! As a child, I loved watching the ancient Chinese dramas, where the court officials have their ‘furry hats’ on, beaded necklaces, and embellished overalls. NOW I know that the beaded ornaments were made from giant clam shells! It was also mentioned that because gold was common in ancient times, the giant clam shells cost a lot more than gold!

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2. Valuing Giant Clams

Shells from Scarborough Shoal were considered of highest grade

I was told by the shops that their shells came from three areas in the South China Sea, and the quality of shells decreases in the following order:

  • The Scarborough Shoal (黄岩岛): Considered the best shell grade because they are uniquely colourful (red, purple, brown, yellow, green, white), and their shells are dense and least brittle. Due to the rarity of shells from the geographic locality, they are highly prized.
  • Spratlys (南沙群岛): Ranks behind those found at Scarborough Shoal, but comes in fewer colours (mainly yellow, brown, white), moderately dense but brittle. Most carving products in the market are made from shells in the Spratlys.
  • Paracels (西沙群岛): The least favoured but abundance of materials. Few colours (mainly yellow, white), and tends to be most brittle of the three. Not suitable for large carvings, and generally mass produced as white beads.

Pricing the products based on colours, translucency, and perfect cuts

Tanmen 2
Table 1. Shell handicrafts were generally priced based on the rarity of colours, translucency, and lack of defects/cracks.

While the origins of shells matters to the craftsman (as it determines the type of handicrafts produced), the products across the various shops were priced quite similarly based on Table 1. For instance, the costs for the same 108-Buddhist beads made with the colourful Scarborough Shoal shells versus the plain-looking Spratlys shells could differ by 50 times (in the Chinese currency, Renminbi)!

Tanmen - 7Tanmen - 6

Giant clam-shell based products are hard to counterfeit

To understand why the locals treasured handicrafts made from giant clam shells, I found myself relating my observations to the biophysical properties of giant clam shells. Here are some reasons:

  • Good quality shells are hard to come by, and in this case, those found at Scarborough Shoal.
  • Every product made from the giant clam shells are unique and one of its kind.
  • They are difficult to counterfeit.

As a young tiny larvae, giant clams are builders. They build their own shells by making aragonite – an alternate form of calcium carbonate. This shell-making process may be affected by the reef environment they live in, for example, the availability of light, nitrogen, or carbon can determine how well they build their shells. To add on, each giant clam is distinctive with their own pace of constructing shells – some individuals may grow very fast, making thinner but bigger shells, while others grow slower, making thicker but smaller shells. Lastly, similar to tree rings, the shell growth pattern of giant clams resemble ‘rings’ – representing days, weeks, or years!

Watanabe et al., 2004
Figure from Watanabe et al. (2004) Palaeo 212: 343-354. (a) Tridacna gigas shell from Kume Island, Japan. (b) Optical transmitted-light photograph of the inner shell layer of T. gigas. Dashed lines represents sampling transect for isotopic measurements.

3. Businesses As Usual? (accurate as of 11-12 August 2016)

After my ground surveys, I mapped out my thoughts and this Figure 1 summarises the simplified version of the various businesses.

Tanmen 1
Figure 1. Mapping out the connections and activities of the giant clam shell business in Tanmen Village.

Business Players Big and Small

The major business players are those with processing factories and warehouses. When I spoke with the owners of these businesses, I found that they have been selling giant clam handicrafts for >10 years, and bought their shells from specialised giant clam fishing boats. By late 2016, where many clam fishing boats have ceased activities, one of the owner boasted to me that they have enough stocks of shells to last them another 10 years of business. She didn’t mention whether their warehouses were nearby, but I believed her words based on what I saw…

The small-time businesses, on the other hand, are not coping too well with their sales. They tend to buy the handicrafts from wholesale, but one man said that business was poor and prices were lower. He has tried his hand to sell online, but hard to compete with the cheaper fakes. They were also very nervous because authorities were beginning to confiscate the products.

Tanmen - 17

Humans of Giant Clams

I met an owner, who previously specialised in carving ornamental jade for almost 10 years. As the market for jade products became saturated causing their prices and popularity to drop, he was looking for alternative materials for handicrafts. Then in 2012, he began to use giant clam shells and have not looked back since. Clam shells became increasingly popular among craftsman, and many started to buy large quantities from the clam fishing boats. He even told me that several Singaporeans had visited him to buy his products in bulk! :O

Another person was a master craftsman with >20 years of carving experience. He had started with jade too, but decided to move his family from mainland China to Tanmen Village to start a wholesale business on the giant clam shell handicrafts – seizing onto the golden opportunities. As I browsed his humble workshop, his wife and himself were beaming with pride and excitement at the prospects of this new business. One that brings in more wealth to improve their living standards.

Tanmen - 19

4. My personal notes

I was sad.

I was sad to see the massive piles of giant clam shells in the backyards of factories, hidden from sight.

I was sad as I realised that giant clams used to be this plentiful in the South China Sea.

I was sad because I felt conflicted between my role to be an objective scientist and to feel emotionally connected with the locals’ livelihoods.

But I was also very glad to have gone through this investigation and seeing the trade unfold.

With such a long traditional history of using giant clam shells as ornaments in China, we risk the loss of an important part of human history. By encouraging the trade, we risk the loss of more giant clams, as well as the destruction of coral reefs in its path. I see the problem, and that is the demand for giant clam shells had led to widespread mining of the seabed for them, and in the process also led to massive destruction of coral reefs.

I don’t think I’ll know where to begin solving this complex problem, and I don’t have any answers for you. Maybe you’re thinking, “After reading your story, and you tell me there’s nothing we can do???” Wait a minute! Give me a chance to leave my alternate ending remarks! 😉

I do know (and hope that you feel the same way) that from experiences like this, I am learning to be more compassionate towards issues that science alone cannot solve the world’s problems. As a close friend told me, “If science had been the solution for all the world’s problems, why are we still having this conversation now?” I just laughed and nodded…


What’s in the Lab?

Not too long ago, I was studying shrimps. 🙂

No no, I did not forget my first love, the giant clams. It was purely coincidental when my colleagues and I came across a pair of shrimps latched onto the giant clam’s gills (or respiratory organs). Based on our earlier literature review on ‘The ecological significance of giant clams in coral reef ecosystems‘, we knew that giant clams hosted shrimps in a relationship known as commensalism.

Commensalism refers to the association between two organisms in which one benefits and the other derives neither benefit nor harm. In this case between the giant clams and shrimps, we think that the shrimps likely had more to gain from living inside the body of a big ‘bodyguard’ and pinching food off from the gills of the clams. Some scientists suggested that the shrimps may cause some harm to the clam host by nipping off tissues from its gills, but this is anecdotal.

Figure 1. A pair of Anchistus miersi shrimps collected from a fluted giant clam, Tridacna squamosa. a) Male shrimp and b) Female shrimp.

We consulted the experts and the shrimps were both identified as Anchistus miersi, and they were a male-female pairing (Fig. 1). The male (Fig. 1a) tends to be smaller than its female counterpart, and the female (Fig. 1b) was brooding eggs (in pale green).

The most interesting observation here was that the same species of shrimps exhibited different spot colours within a single population (found in a single giant clam)! Here, when alive, we observed that the male shrimp had red dots and the female shrimp had blue dots. Upon preservation in ethanol, both specimens revealed a mixture of red and blue pigments. We concluded that the species, Anchistus miersi exhibit dichromatism.

Dichromatism means the occurrence of two different colours in animals. So why do they exhibit dichromatism in the same species? We simply have no idea yet! There are no obvious advantage or disadvantage being colourful as they live inside the clam host for their entire lives. The simultaneous occurrence of red and blue pigments does suggest that the colour pattern is not fixed.

So can the shrimps change their spots? Even more questions!


  • Neo, ML, BY Lee, K Vicentuan & PA Todd (2015) Dichromatism in the commensal shrimp, Anchistus miersi (De Man, 1888). Marine Biodiversity 45: 877-878.


I just popped a GIANT paper!

After an incubation period of almost 3.5 years long, I’m a proud ‘mom’ of this new OpenAccess publication 🙂

Neo et al. (2017) Chapter 4. Giant Clams (Bivalvia: Cardiidae: Tridacninae): A Comprehensive Update of Species and Their Distribution, Current Threats and Conservation Status. Oceanography and Marine Biology – An Annual Review. Volume 55. Pp. 87-388.

What started out as a desire to produce an erratum for an earlier review paper has turned into a monster paper (301 pages)! Throughout the process, I felt like a detective – spending hours mulling over every piece of evidence, and snowballing my clues from paper to paper. I spoke to people via emails, and anyone who would give me an inkling of ‘where can I find giant clams?’ I trawled through thousands of photographs and identified each one of them to species. At the end of my compilation, I needed the other experts to verify my findings and I’m so very thankful for their utmost contribution and commitment. Without my precious collaborators, this work would not have been the most solid foundation for advancing knowledge on the giant clams.

From here on, I hope that our paper will serve its purpose and help many other scientists, managers, and public members to view these amazing animals through my lenses. 😀

9781138197862_oachapter4 1

The Story of Shells – Part 1

Disclaimer: Opinions are mine.

‘South China Sea’ and ‘Giant clams’ are possibly two key phrases that have been connected on many occasions in just 2016 alone. Some of you may have read how the widespread poaching of giant clam shells in the South China Sea caused the wipeout and massive destruction of reefs.

Almost exactly one year ago, on 30 November 2016, the Hainan Province had decided to amend their existing ‘Republic of China Marine Environment Protection Act’ and the ‘Republic of China Wild Animal Protection Act’ to include both coral reefs and giant clams. This also meant a province-wide ban on the sale of corals and giant clams beginning on 1 January 2017. Although ground observations pointed out that the sale of giant clams has always been illegal with weak enforcement.

Beyond the borders of Hainan Province, authorities on mainland China have intercepted a shipment of giant clam products, reported in September 2017. The brief article pointed out that ‘giant clams listed as a Class I state-protected animal in China’ – also learning that the pandas are listed on this same category! What a vast difference in ‘protection levels’ between them!

My interest in this subject matter began when my colleagues from the Centre for International Law (NUS) invited me to discuss about topographic features of South China Sea (i.e. mapping of reefs). I began to do some research on my own about the shells and industry, with the help of my senior mentors such as Professor Ed Gomez.

There were plenty of information from both the English- and Chinese-based media, and I saw a problem. I realised that the majority of readers have formed a (very) negative image of the Chinese and blamed them for what happened in the South China Sea and the giant clams. Lucky for me, I can read English and Chinese (yes, in Singapore, we learn two languages as kids!), my colleague and I read lengthy forum posts on how there were many Chinese people (and scientists) who were equally outraged by what was done in the South China Sea and the giant clams.

And so, I decided to make my way to see the famous ‘giant clam’ village for myself. This trip would not have been possible if it were not for my gung-ho collaborator and guide. What you will see here on is my photo-essay of the two-day trip in August 2016 to Tanmen Fishing Port on Hainan Island, just a few months before the announcement of the sale ban. [P.S: I did felt like a detective snooping around! 😛 ]

This is my story of the giant clams in the South China Sea…

Tanmen - 1
This simple monument marks the entrance to the Tanmen Centre Fishing Port.

The weather was dry and warm. Then again, Hainan’s weather does not get very cold even during winter season. My companion and I arrived in Boao (博鳌镇), which is approximately 10 km to our intended destination – Tanmen (谭门镇). I remembered feeling very nervous and jumpy because we met with difficulties in getting transport into the town, and we were constantly being ‘cheated’ of our fares. I remembered also feeling excited at the prospects of what I would see first-hand in this town.

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A traditional fishing town, this is the fishing vessel used for long-range fishing in the South China Sea. The light bulbs on the second deck are iconic features of these vessels. This vessel specifically flies the Chinese Flag State.

Tanmen fishing port is the largest fishing port on Hainan Island, as rated by China’s National Agriculture Bureau. It is also a distribution centre of marine products in Hainan. As we walked along the pavement next to the mouth of the sea, we saw the fishing boats lining the port – no signs of fishing. I later found out that there is a mandatory annual fishing ban between April/May to October in the South China Sea to allow for recovery of fish stocks. The fishermen would go fishing in the South China Sea, which is a very long way from home. Often, they would have to live on their boat for almost a month long before returning home with their catch.

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Photographs here depicting the old looks of Tanmen Bay, which includes fishing and aquaculture-like facilities.

Flabbergasted is a word that I would not use lightly but it is appropriate for what I am about to describe. We saw streets after streets of shops filled with nothing but handicrafts made of giant clam shells. It was said that the rise of the giant clam handicraft industry also saw the number of retailers increased from 15 in 2012 to a whooping 460 in 2015. By 2015, this industry was supporting nearly 100,000 people, according to estimates.

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Today, the town has transformed into a shopping district with consecutive shops selling giant clam shell handicrafts and jewelry.

We popped into a few retailers and began to converse with them about the industry – how and when they had started their businesses, and to hear pride in their voices when talking about these Hainan giant clams. It was like the ‘gold rush’, only that this was a ‘clam rush’. 🙂 As I was browsing their products, I was also admiring the craftsmanship that was put into each item. Many of these products reflect the strong and rich history of Chinese cultures, and are symbols of wealth, health, luck, and prosperity. They are also attractive as display ornaments.

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Retailers taking different marketing approach to attract clients. The text says, in brief, that giant clams, a precious organic gem, are considered one of the seven treasures in the Buddhist scriptures ‘Jin Gang Jing’. It has calming powers, and also used for praying purposes.
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Intricate carvings that still resemble the giant clam shells, portraying typical icons of religion (L) or scenes from ancient China (R).
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Giant clam shells are ‘graded’ based on its location, colours, and translucency. The ‘blood-red giant clam’ (top L) was most valuable, followed by purple, orange, dull green, yellow, and white. Buddhist prayer 108-beads (top R) and large carvings (bottom) are examples of handicrafts.
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Retailers also show their prized craftsmanship that are not for sale, but demonstrates the quality of their products. Here shows the Goddess of Mercy that won the Silver Prize for China’s Jade Stone Carving Award with certification.
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The 18 Arhats (十八罗汉) depicted in carvings on giant clam shells were intricate, exquisite and expensive. They are the original followers of Buddha, and are charged to protect the Buddhist faith. In China, the 18 arhats are a popular subject in Buddhist art.
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Various animal lucky charms, from Arowana fish and frogs to imitating elephant ivory tusks. All symbols are iconic to the Chinese culture and beliefs of affluence and luck.
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Top: Apart from the Tridacna species of giant clams, I also found Hippopus species on display. Bottom: The lowest grade and quality of giant clam shells (white and opaque) are rapidly transformed into beads for wholesale distribution. The room was filled to the brim with bags and bags of threaded beads waiting for buyers.
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Spying the cabinets, I found coral skeletons also being used to make pendants. It’s hard not to miss the unique corallite shape. Retailer says that they are not as popular as those made from giant clams.
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Business appeared slow. This shop was closed for holiday, and used cardboards to cover their products. I was unsure why the need to cover their products, but heard that authorities were slowly clamping down on businesses.
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Jack of all trades – these retailers selling bicycle parts and strings of beads made from giant clam shells.
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Like breadcrumbs, we followed the trail of broken beads along the beach. It was clear that these beads did not make the cut to be put on the shelves.

By the fourth retailer, I was already exhausted. The shops began to look very similar to each other. The shops were selling very similar items. My companion and I then wandered off the fancy streets and into the housing areas. There, something caught my eye – the trails of broken white beads. As I followed them like breadcrumbs, they led me to a huge puddle of them laying abandoned. Eventually, we were standing in front of a warehouse that was surrounded by piles of fossilised giant clam shells. They were covered with sheets, seemingly trying to hide from view. We were shortly ‘chased away’ by the foreman…

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The beads led us to this massive stockpile of yet-to-be processed giant clam shells that appear to stretch for forever.
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Capturing behind the scenes in a small processing factory.
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Given the hardness of these shells, I found an angle grinder used to cut them into smaller pieces for carving and moulding.

To have this opportunity to speak and meet the people driving the industry was insightful for me. Admittedly, the methods used to harvest these raw materials was harmful and destructive to the environment in the South China Sea, but the industry became an important element supporting the livelihoods of people living in Tanmen. This is a conservation dilemma…

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A crafts master shared with me that he only carves white cabbages (白菜), which symbolises wealth and prosperity.
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Not just hand-made, some of the items were created using computerised printing. It reminded me of the 3D printer.
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The living were not spared. I found the shells of freshly poached giant clams and hard corals hidden in a dark room. The clean inner surfaces of shells and lacking thickness suggest that they were recently dead. In most instances, the fossilised giant clam shells rarely come intact and with complete paired shell valves.

From a scientific point of view, it was a good opportunity to have been on the ground and surveying the industry. It was exciting to pose as a potential buyer and talk to the locals to find out more about the products and what made them so proud of their giant clams. It was sad to see the vast numbers of giant clam shells on the streets and in the factories. It was interesting to observe these raw materials first-hand and how they were transformed into beautiful pieces of articles.

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The limited source of ‘blood-red’ giant clam makes them highly sought-after and valuable to retailers and buyers. 
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Trapped Hippopus spp. shells in crates.
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We wandered into a medium-sized factory and stumbled upon even more piles of raw materials: fossilised giant clam shells. I can only imagine the sheer number of giant clams that once lived in the South China Sea that were first harvested as food and now for their shells.
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These shells were dredged up from the bottom of seabed and coral reefs in the South China Sea. In the process, this destroyed large areas of coral reefs.
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Semi-processed shells comprising at least four species of giant clams: Hippopus hippopus, Hippopus porcellanus, Tridacna derasa, and Tridacna gigas.
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Corals under cover.
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An advertisement board sharing the cultural value of giant clams. A unique aspect was the comparison with western culture using the Birth of Venus.
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The China’s president famous visit to Tanmen Port in 2013 that was said to have spurred the fishing exploits to the South China Sea.

This is the first part of my insights of the industry. Stay tune for Part 2 of my story that will elaborate why these giant clam shells are significant in the Chinese cultures, the value and quality of giant clam-based products, and interview bits and blobs with the local crafts masters and shop owners.

What’s in the Lab?

Some years ago *ahem 10 years*, my classmates and I had to produce a video to showcase animal behaviour for an undergraduate class assignment. Of course, we decided to do one on the giant clams! 🙂

Unknown to many, giant clams do exhibit a wide variety of behaviour as presented in this paper by Soo & Todd – The behaviour of giant clams. One of the most interesting behaviour for me is watching the little clams walk around! Yes, they can walk!

In order to find out how fast they walk, we set up an experiment in an aquarium tank. We laid grids to help us measure the distances moved by the clams at the end of experiment. We first arranged the baby clams neatly in rows and columns, and later remotely monitored their ‘movement’ using web-cam and infra-red cameras over 24 hours. These pictures showed the before and after of experiments, and we can see that the clams messed up our arrangement!

Soo & Todd 2012 Results
Extracted from Soo & Todd (2014).

If you like to read up more about how and why they are motivated to go walking around, I have an older post on “Why did the giant clam cross the road?” Also, do watch this video on how we conducted the experiment. We definitely had plenty of fun designing and setting up this experiment. Enjoy! 😀

TED Talk – The fascinating secret lives of giant clams


Again, I like to thank the many individuals mentioned here for making this dream happen. Now, giant clams – show the world what you got! 😉

You can watch it here:

For more information about the conservation work on giant clams, you may read them in the various posts titled “Conservation of giant clams – Parts 1, 2, 3, 4“.


Field work – Bachok Marine Research Station (11-16 June 2017)

First and foremost, thank you to my collaborators, Professor LIM Po Teen, Dr LEAW Chui Pin, and Professor Aileen TAN, as well as the Malaysia Marine Park for supporting our field research to survey the giant clam populations in the Perhentian Islands, Terengganu! Also, thanks to L’Oréal Singapore For Women in Science National Fellowship for supporting my research! 🙂

Field sampling for giant clam tissues to examine the population genetic structure in Perhentian Islands. Credits: Lim Zhen Fei.

Continue reading “Field work – Bachok Marine Research Station (11-16 June 2017)”