27 June 2011

Thousands of fish escape AVA fish farm?

Word in the fishing community was that thousands of fish were on the loose from an Agri-Food and Veterinary Authority (AVA) farm at St. John's Island, said a recent Straits Times article. Fishermen flocked there and returned with "bags and bags of fish, and it was all sea bass".
Fish farm off Lazarus Island
Fish farm just off the natural shores of
Lazarus Island off St. John's Island, Jun 2009
AVA confirmed that sea bass had escaped from its farm earlier this month, in its first such incident in five years. It said fewer than 500 fish had escaped through a 10cm tear in the net-cage which when full can contain 10,000 to 20,000 fish.

The AVA spokesman did not say how the tear occurred at their fish farm at St. John's Island.

Do fish escapes happen often?
The Straits Times report quoted Mr Yeo King Kwee, who runs a farm off Lim Chu Kang, and said 5,000 sea bass fingerlings escaped last month, costing him $6,000. He said: "I went to feed the fish and no fish came to the surface. I knew there was something wrong, and when I pulled up the net I saw a huge hole in it."

What is the environmental impact of the escape?
According to the Straits Times report, Mr Joep Kleine Staarman, who runs a sea bass farm on Pulau Semakau, said the escape is unlikely to have any ecological impact on the area. He said: 'It's a local fish - there are wild sea bass all over the southern island waters. The number that escaped is quite small"

The report also said that the AVA farm at St. John's Island also conducts "growth trials of fish such as sea bass, cobia and pompano", in addition to "developing new cage designs to improve fish production".

According to the Guide to Common Marine Fishes of Singapore, the following are native fishes: Cobia (Rachycentron canadum), Barramundi/Sea Bass/Siakap (Lates calcarifer) and Pompano aka Snubnose Dart (Trachinotus blochii).

All these fishes are carnivorous.

According to a recent report by The WorldFish Center, with aquaculture on the rise, the question is how can we make sure that it doesn't put an undue burden on the environment, so that best practices are used and species groups are cultured that don't have excessive impact.

The report says fish farming can have environmental benefits if done sustainably. Fish process energy more efficiently than mammals such as cows and pigs because they are cold-blooded (so less calories are needed for warming themselves) and live in water (so relatively more of the body converts to muscle than bone). The authors say that for each kilogram of protein from beef, a cow needs to be fed the equivalent of 61kg of grain, for pork, a pig needs 38kg, but for fish it is just 13kg of grain. In addition, says the report, aquaculture emits less phosophorous, nitrogen and greenhouse gases than livestock farms.

However, it warns farming can have a greater negative impact if it focuses on carnivorous fish, which require food from outside the farm. There is a lower impact from herbivorous fish, or better still seaweed, mussels, oysters and molluscs.

In October 2010, US researchers released the first scientific index designed to measure the impact of fish farming on the environment. The "Global Aquaculture Performance Index" is intended for use by "industry, farmers, bureaucrats, government ministers and other decision makers." The tool is similar to the "ecological footprint" concept used around the world to assess the overall impact of humans on the environment.

The index measures the impact of fish farms according to 10 factors. These include the impact on the environment of capturing fish in the wild; the use of cleaning chemicals and antibiotics; the economic damage incurred when farmed fish escape into the wild; energy costs; and the impact on water oxygen levels.

The researchers noted that "The fastest growing sector is Asia, where we found a troubling combination of poor environmental performance and rapidly increasing production." They added that "nearly anything coming out of Asia is problematic," because of unregulated use of antibiotics, spread of parasites, and a greater use of wild species caught without regulations. "Some aquaculture production systems enable and facilitate unsustainable fisheries practices."

Are best practices in place for fish farms in Singapore?
In Jun 2009, I came across massive fish farm equipment 'parked' on the natural shores of Lazarus, just off the AVA fish farm at St. John's Island.
Fish farm equipment 'parked' on Lazarus Island?
In May 2011, we took a closer look at a huge contraption 'parked' on the natural shores of Pulau Semakau, just near the fish farm there.
A recent article in Channel NewsAsia reported that fish farmers in the North do not have proper facilities to unload their catch to the mainland.

Fish farmers who illegally load or unload their stocks by beaching their boats at Pasir Ris Beach Park have been fined. They have been asking for proper facilities for two years.

Climbing a ladder up to Changi Jetty is the only way for fish farmers in the eastern waters of Singapore to legally load and unload supplies and fish stocks that can sometimes weigh hundreds of kilograms. And the Manpower Ministry's Workplace Safety and Health has deemed this practice to be dangerous. This location is also double the distance from Pasir Ris Beach Park.

At the same time, according to media reports in March 2011 AVA is setting targets for the 95 coastal fish farms to yield a minimum of 17 tonnes of fish per half-hectare of space annually. That space is the average size of a fish farm here. Their licences may not be renewed if targets are not met within two or three years.

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