11 December 2009

What goes on at Singapore's largest commercial fish farm?

Located south of Pulau Semakau, Barramundi Asia Farm and Nursery has a 2-hectare $3million fish farm using European and Japanese sea cage fish farming technology.
Photo of the fish farm taken on 3 Aug 08. The same area is also used to park huge oil rigs in Singapore for repairs or maintenance.


Where is the fish farm located?
This is probably the fish farm referred to in the location map in the MPA Port Marine Notice of May 08.

What happens at the fish farm?
The farm raises 'super fry' which are engineered by local marine scientists at AVA's Marine Aquaculture Centre. They are genetically selected seabass that grow 15% faster than average.

The 1cm fry spend two months in the Semakau nursery before being transferred to the sea cages. The farm has 14 steel cages and will eventually have 36. Each cage is 15m by 15m, able to contain 30,000 fish and located at a depth of about 10m.

Fed twice daily on imported dry pellets, the fish take 18 to 24 months to reach the desired weight of about 1kg. There is an automatic feeding system, instead of feeding by hand. As well as an automated vaccination system to individually vaccinate each fish.

The farm has a yield of 80% as some fish are lost to disease despite being vaccinated.

What happens to the fish from the farm?
The company started harvesting from the sea cages in October. 80tonnes have been harvested so far. 500tonnes will be harvested this year and the target is 3,000tonnes a year by 2012, which would represent 86% of Singapore's current local fish production and 3% of total fish consumption.

The harvest is sold to Jurong Fishery Port or to restaurants. The farm's harvest is also available at local supermarkets such as Sheng Siong.

What are the plans for fish farming in Singapore?
Granted a licence in May 2008 for the Semakau fish farm, the company aims to set up a second fish farm in the area to produce another 3,000 tonnes by 2020, and to look at supplying other varieties such as red snapper.

AVA said with an additional four similar farms, Singapore can meet 15% of its total fish consumption. Minister for National Development Mah Bow Tan said the Government wants to increase local fish production from 4% to 15% of consumption - about 15,000 tonnes of fish - and will require another four or five farms the size of Barramundi Asia.

Is Singapore a good place for fish farming?
Barramundi Asia said it prefers Singapore waters as these are sheltered from tsunamis, earthquakes and typhoons.

There are 106 licensed coastal floating netcage fish farms in Singapore's coastal waters. Last year, the marine aquaculture industry produced 3,235 tonnes of food fish at a value of $11.4million. Grouper, seabass and snapper are produced, as well as crabs, shrimp and mussels.

Full media reports on this on the wildsingapore news blog.

What is the impact of the Semakau fish farm on the surrounding marine life?

First of all, is there marine life nearby? Yes, the shores of Pulau Semakau and nearby submerged reefs are very much alive.

Unfortunately, the media reports did not address some of the potential impacts of aquaculture. These include:

What are the farmed fish fed with?
Although aquaculture is often touted as a solution to overfishing, ironically, fish and marinelife may continue to be overfished in order to feed the farmed fish.

What is the impact on surrounding marine life of massive fish populations confined in the cages?
Fish diseases can impact not only stock but also marine wildlife. Farms may use antibiotics and other chemicals on their fish stock. These together with wastes from the fish stock are also released to the surrounding marine ecosystems. Excess nutrients and wastes can cause ecological upsets such as algal blooms. Escaped farmed species may become invasive and disrupt our native marinelife.


Related posts
Related articles on Singapore aquaculture
Related articles on aquaculture in general

3 comments:

  1. What's the impact on the environment due to the discharge of veterinary medicine (vaccine, anitbiotics,etc) used in fish farming if any.

    How is the waste water treated before discharging to the sea.

    Rgds

    ReplyDelete
  2. Those are important issues indeed, Anonymous.

    ReplyDelete
  3. Addressing some issues are:

    Fish are often fed with fish meal. They are processed fish from what you call trash fish. Most fishes that are deemed undesirable or inedible may be bought by such companies, processed and converted into a brownish substance they call fish meal. Fish meal and oil forms a major component of aquaculture feeds. More research is on the way to reduce this component, substitutes often use hybrid plant and animal sources. Although it may be seem unsustainable to feed fishes caught from the wild to feed our farm fishes. The Food Conversion Ratio (FCR) remains the lowest compared to cattle, pigs, sheep and poultry.

    The next issue is environmental impact. Chemical wastes are not much of an issue. Vaccines can be administered internally or externally like bathing a fish. There is no impact if its the former, but the latter may be of concern, if vaccine treated baths are not disposed properly. Most farms would choose the former method as it provides a longer lasting protection. Antibiotics are a decreasing trend as more farms adopt vaccination. Still, antibiotics are used but not on a large scale (if the farms have to keep their accreditation). The issue regarding antibiotics being of concern only points to developing resistance in bacteria which could infect humans, humans who fall sick by these bacteria would die since the same antibiotics does not work. Chemicals are used to kill fish parasites, chemicals like cypermethrin, interestingly has a short half-life, meaning it degrades quickly and does not have a large impact on its flora and fauna.

    Fish wastes are an issue in fish farming (in regards to Singapore). There are two ways to handle fish wastes. The first is to practice fallowing, meaning allowing a piece of land (or sea/river) to "rest". Basically, fish farming operations simply stop and move to other locations to resume farming. Companies practice fallowing need to own multiple locations of sea area to make it feasible which of course land-scarce Singapore cannot afford to do so. The next option only applies to closed fish farming systems, where fish wastes like nitrates and phosphates are sequestered by micro/macro algae as well as bacteria to perform nitrification and de-nitrification.

    Fish escapes are another issue. Often, fish are selectively bred to optimize growth but the effects of genetic pollution are minimal. Logically speaking, a fish that is bred to just eat and grow big cannot survive in the wild, they are very likely to be eaten by predators and therefore pose little threat to genetic pollution. Of course, an increasing trend in research and development are to develop triploid fishes. While not many fish species are using triploid fishes, using triploid fishes eliminates genetic pollution because they are sterile. Lastly, choosing a fish to raise specifically often requires assessing its environmental impact in the event of fish escapes. Fishes like tilapia are raised but considered undesirable as they are an invasive species in countries like Australia and America.

    To sum it all up, there are actual issues to resolve such as compromising coral reef ecosystems, waste management in sea cages, whether if they practice fallowing in land scarce Singapore.

    ReplyDelete

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