Crab Condominium Farming in Singapore and Vietnam

Crab Condominium Farming in Singapore and Vietnam

Published: 2024.03.01
Accepted: 2024.03.01
85
Associate/Lecturer
Singapore University of Social Sciences (SUSS)

ABSTRACT

Some Singaporean crab breeders specialized in boxed drawer crab rearing were trained in a workshop founded by a boxed crab-rearing hobbyist/enthusiast. They turned their interests into individual food self-reliance ventures while keeping in touch with a growing community of restaurants and enthusiasts with the eventual ambition of starting a hatchery. By comparison, an enterprising Vietnamese box crab farming family has also built up their own farm system. This crab-rearing family rely on locally-sourced ingredients like mussels to feed their crab fries and then rear them until they are of a saleable size. They find certain advantages with boxed crab-rearing such as a controlled environment, space-saving benefits, etc. although the feeding procedure required meticulous feeding schedules. Some Singaporean urban crab farmers aspire to apply the same methodology to rearing lobsters, crayfish and other crustaceans. Because market-originated crabs are often kept in storages for too long, they become skinny and needs to be fattened up. Therefore, rearing one's own crab can actually produce more desirable products for consumption although some precautions are in place when growing crabs, e.g. not giving affectionate names to living things that one would eventually consume as food. It is a good habit to track and maintain an optimal level of ammonia in the water. Finally, in the case of the Vietnamese crab farmers, if they succeed in boxed crab rearing, it may become a viable alternative to lagoon crab-farming which are prone to diseases, and this can win political support for the successful farming commune.

Keywords: crabs, Singapore, Vietnam, box, drawer

INTRODUCTION

Singaporean urban farmers are creating a new reality in crab-rearing in Singapore’s densely populated high-rise apartments, including the ubiquitous Housing Development Board (HDB) flats in which majority of Singaporeans resides in. Starting from 2016, Singaporean urban farmer Shannon Lim (aged 37) dabbled with the construction of crab condos when he was inspired by an online forum posting years back about rearing crayfish in plastic drawers and Lim decided that was just as suitable for rearing crabs (Ng, 2023).

While Lim may have started crab drawers cultivation as a hobby or side-interest, Vietnamese crab farmers started using the methodology for commercial purposes from 2023 after conducting research for 3 years. The concept itself reached Vietnam sometime in 2019, according to industry sources and it was first applied on mud crab (Vietnamese Fisheries Magazine, 2023). In 2020, after being acquainted with crab drawers rearing method by someone from his network, Tran Xuan Giang from Hoang Tan Commune [in Quang Yen town (Quang Ninh)] was convinced of the commercialization potential of the methodology and conducted his own research through various sources and hands-on experimentation (Bac Giang Newspaper, 2023). Giang came from a family of lagoon crab farming with more than a decade of experience and, while lagoon crab-rearing provides reasonable revenues, the crabs in the lagoon frequently get ill, reducing profits and value for the farmers (Bac Giang Newspaper, 2023). Giang also found that maritime sea crabs in plastic boxes can allow him to manage the volume of crabs, disease mitigation, well-being and efficiency of harvest (Bac Giang Newspaper, 2023). Box-rearing can also prevent cross-infection and minimize losses due to the natural phenomenon of crabs attacking and eating each other (Garran, 2023).

Unlike Giang, Lim mainly worked with crab enthusiasts and crab farmers. For educational purposes, Lim conducts lessons to teach Singapore residents methods in modifying standardized plastic storage drawers (affectionately known as ‘crab condos’) to farm their crabs. ‘Condos’ are Singaporean lingo for condominiums which conjures up the images of privately-owned apartments that are either leasehold for 99 years or, in the rare cases, 999 years or freehold and they are usually equipped with tennis courts, swimming pools, security posts and sometimes even saunas.

Lim, aged 37 years old, started teaching these lessons in 2016 and the crab drawer farming’s stakeholders floated the ambition of cooking seafood meals domestically without purchasing any from the marketplace (Ng, 2023). Along with this dream or vision, many can simply net one up from their own crab drawers. Contrasting his home-grown crabs with those from the market, Lim grumbled that he often purchased crabs from the open market that were left in commercial storage warehouse excessively long: “They get skinny and become water crabs – they’re called that because they’re mostly water and they’re less valuable. Then we just start fattening them up again.” (Ng, 2023)

BECOMING VALUE-ADDED PRODUCTS

However, the Vietnamese experience indicated that due care must also be paid to rearing boxed crabs as well. With regards to health and well-being of crabs, the Vietnamese boxed crab farmers discovered in their own research that it is mandatory to monitor water quality, temperature and the wellbeing/appetites of the crabs in order to optimize the system to maintain a good environment for the crabs (Bac Giang Newspaper, 2023). In the initial phase of experimentation, after more than 10 days of keeping more than 600 crabs in plastic boxes (the plan is to eventually expand to 3,000 crabs), the Giang family’s boxed crab survival rate is 93-95% at about 15-35 days before the molting day cycle when the crabs are suitable for harvesting, it is also the stage when the peeled crab are most nutritious and in demand by many crab traders and restaurant owners (Bac Giang Newspaper, 2023). The average selling price of peeled crabs are from VND650,000 to 700,000 or approximately US$26.63 to US$28.83 per kg (higher than commercial lagoon crabs raised in lagoons that are priced from VND200,000 to 250,000 per kg) (Bac Giang Newspaper, 2023).

Unlike the Giang family’s large-scale crab farming ambitions, Singapore’s Lim focuses on educational and instructional ventures. He is the progenitor of the OnHand Agrarian outfit that conducts workshops/lessons where he instructs participants how to build the "crab condos" and rear them properly. Lim’s fees for the course comes up to S$680 (US$510) for a 10-hour course segmented into 2 days, and the course fee includes payment for the use of equipment to construct the crab condo, tools needed and transportation back home after the lesson while fee payees can bring a guest to the class if it is not full capacity (Ng, 2023). For Lim, the so-called crab condo is a tower storage of plastic drawers that are seven "floors" tall housing one crab per floor and the compartments are inundated with freshwater and equipped with pumps, filters and an ammonia evaluation kit for determining safety for crab, along with an ultraviolet steriliser and algae that degenerates organic by-products to remove bad odour (Ng, 2023).

Their Vietnamese counterparts, the Giang family, relies on local crab species and river water for the boxed crab cultivation. The species of crabs grown in box drawers in Vietnam are acquired from domestic crab farmers and the individual healthy baby crab comes up to approximately 2-2.5 g, while the water source piped into the crab boxes is extracted from the Ben Giang River which has the same salinity used for the lagoon crab farming. The Giangs operate a family factory system of 648 individual crab-rearing plastic boxed drawers (measuring 30 by 40 cm) allow the crabs to age and size up in the enclosed environment (Bac Giang Newspaper, 2023).

Vietnamese crab drawer farmers like Giang noted the space-saving advantage in using such compartmentalized box technologies to rear crabs as opposed to the aquatic environment needed for rearing lagoon crabs (Ng, 2023). Giang is not the only one. Successful box crab farmer Nguyen Buu Loc in Phu Quoc City (Kien Giang Province, southern Vietnam) and his wife began rearing crabs in plastic boxes because of overharvested exhausted seafood resources in the maritime sea (Thanh, Ha and Chi Cong, 2023). Under such manmade condition, each crab can grow from a few hundred grams to almost 2 kgs or more and internet-based seafood retailers often offer live crabs between 300g and 1kg (Ng, 2023). In comparison, Vietnamese drawer-bred crabs that are commercially sold weigh approximately 3 to 4 crabs per kg, and are sold for VND650,000 to 700,000 per kg or approximately US$26.63 to US$28.83 per kg (Bac Giang Newspaper, 2023).

Similar to the Giangs, Vietnamese crab farmers Son and Ly (a husband-wife pair) acquired their baby crabs from the local community’s fisher-folks by local fishermen as they discovered that, by rearing from the stage of baby crabs caught from the wild, they are “generally healthy, not vulnerable to diseases, and grow fast” (VFM, 2023). These baby crabs are initially kept in large tanks till they reach an appropriate size before their release into plastic boxes where they are given fish seafood like herring, clam, mussels, and snails (VFM, 2023).

While the Vietnamese Giangs experiment with commercial sales, Singaporean Lim’s disciples is just glad to rear the crabs for his own culinary quests. One of Lim’s students, management consultant Lee Ray Sheng, aged 24 and a kayaking enthusiast and mussel picker off Singapore’s floating safety barriers, provides food for his crabs once every 2-3 days, remarking: “Crabs eat absolutely everything, so the easiest way is of course to go to a fish monger and ask them for fish gills. Normally when I go kayaking, I go with some friends, I just go to (Pulau) Ubin and try to spot animals. But now, going to Ubin has a very different purpose.” (Ng, 2023) Besides fish gills, the crabs in the condos are also given mussels; consequently, the flexibility in designing their diets makes them appropriate for urban farming in Singapore (Lee, 2024). Lee Ray Sheng’s crabs grew by 50% in size in only two months, simply by feeding them once every 2-3 days (Arain, 2023).

For professional boxed crab farmers in Vietnam, the dietary needs are more elaborate. Feeding Vietnamese box crabs is more tedious than lagoon crabs because their diet consists of fresh locally-caught seafood like oysters, fish and mussels (domestically-sourced instead of using imported feed lowers the feed costs) that has to be inserted into individual feeding box 2 times daily at the 7th and 17th hours of the day (Bac Giang Newspaper, 2023). The cost of these small fish, clams, mussels, and snails feed come up to approximately VND40,000-50,000 (US$1.7-2.1) per day (Nguyen, Khang and Le Minh, 2023).

While the Giangs have a backlog of experiences in crab-rearing and approach the tasks gingerly through experimentation, Singapore’s amateur boxed crab farmer Lee chanced upon the venture rather serendipitously. He said he first knew about vertical crab farming a few years back when he visited another farm before coming across OnHand Agrarian when he saw a Tik Tok video about Mr Lim’s crab condo classes, recalling: “First thing, I love to eat crab. Second thing, I’d definitely love to grow my crabs and eat them. So I signed up for the course … and I built my own crab condominium. [His crabs from the lessons were as big as the circumference of his palm, and he guesstimated that they expanded in size about 50% in two months].” (Ng, 2023)

Lee noted that prawns and cave-inhabiting fish can also be reared in the crab condo, something that Lee has implemented in addition to rearing crabs after gaining the knowledge from Lim: “If I could rear lobsters, I would gladly rear lobsters. [Lim] mentioned that that’s a lot harder, the environment needs to be more controlled. I was handling one of the crabs and the crab decided to cut off its own arm … and his pincer just dropped off [an action they do when they feel threatened]. It became an upgrade for my instant noodles. [If he decides to cook one of his crabs, he will make] Chilli crab.” (Ng, 2023) As to the last point, an advice that Lim provides to his students is not to give affectionate names to their crabs, especially if they want to consume them, to avoid forming an emotional attachment (Ng, 2023).

At a macro level, with food security in mind, before the COVID-19 coronavirus pandemic, Lim instructed approximately 50 students on how to construct crab condos and he wants to motivate more Singaporeans to be urban farmers and crab growers (Ng, 2023). Touching on overdependence on seafood imports, Lim argued “I’d like to see more Singaporeans growing their own food because we are ridiculously dependent on Malaysia. [Lim’s grandparents’ WWII deprivation stories inspired him to think about food security] It kind of affected my view of how we should be a bit more prepared for strange things to happen.” (Ng, 2023) Lim noted many Singaporeans are enjoying consuming crabs and that processing and preparing a crab for a meal is more basic than removing the scale, slicing, de-boning or filleting a fish (Ng, 2023).

Lim rears several fish species in his own indigenously made fish tank that double up as a regular-sized table, reared small flocks of ducks (pets that may double up as food), 200 crabs in Pasir Ris and his Simei home farm, and small-sized herbs like mint/stevia in his home farm’s aquaponics system made from recycled bottles (Ng, 2023). Lim accepted assignments from hotels, schools and individuals to establish farming systems while retailing seafood and veggies for signed-on customers who may be too busy or uninterested in growing and rearing their own foods, and even offer hatchery services to paying clients to rear crabs on their behalf (Ng, 2023). In this service, Lim’s OnHand Agrarian takes care of 200 crabs for paying customers (Session An, CNA and Temasek, 2024).

The deal that Lim provides for his customers who want him to rear their crab is detailed here. Lim receives a one-off payment of S$28-$37(approximately US$20.88 to US$27.59) for interested customers to buy a crab for a boarding period of two years in a drawer unit at the crab condo where they will be fed and cared for 2 years until it attains a weight of minimally 1.5 kg (Shout, 2023). If the crab turned out to be below 1.5 kg by the end of 2 years, the customer can select additional crabs to make up for the weight to take home to eat (Shout, 2023). Lim eventually hope to set up Singapore’s own professional dedicated hatchery because crabs cannot copulate and give birth in the condo set-up, so a hatchery can provide farmers with babies to rear (Ng, 2023).

If the Singaporean boxed crab farmers were to bring their activities up a notch to rear crabs commercially, Singaporean urban farmers (including crab farmers) must try to convince local consumers to go local because even more essential food products like leftover green vegetables supplied by domestic vegetable farms remains a problem (Ng, 2023). Given the young history of the crab condo methodology, it is unlikely to be a significant replacement in Singapore for market-sold crabs yet, but it is likely to contribute to less dependence on imports, something important should another crisis like a pandemic happen. 

CONCLUDING REMARKS: POLITICAL ATTENTION

As for the Vietnamese Giangs, boxed crab farming is more than a fad that appears to have autonomously popped up in various locations in Southeast Asia (SEA) or a hobby, their farms carry the potential to be a model farm should their production output improves and their attempts at commercialization succeed. On 7 July 2023, Hoang Tan commune’s Tran Xuan Giang spent more than VND2023 million (approximately US$83,000) to set up his crab farm using plastic boxes in Quang Yen town, becoming a local community aquaculture expert and a “new model” farming pioneer (Bac Giang Newspaper, 2023). He has gained local political support from the Party as well.

Dam Chi Thiet, Secretary of the Party Committee of Hoang Tan Commune (Quang Yen Town) praised the Giang family and provided political support: “Although the model of raising sea crabs in plastic boxes of Mr. Tran Xuan Giang's family is in the pilot stage of farming, it has attracted a lot of attention and interest of many farmers to visit and learn from his experience. Currently, Hoang Tan commune encourages households raising oysters, fish in cages, etc. to switch to developing new models, applying high technology to production. In the future, if the model of raising sea crabs in plastic boxes continues to be implemented with high efficiency, the commune will create favorable conditions for people to come to learn from the experience, apply and replicate this model, towards building a business. Hoang Tan crab brand becomes a local OCOP [One Commune One Product] product.” (Bac Giang Newspaper, 2023)

REFERENCES

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