SINGAPORE - The Agri-Food and Veterinary Authority of Singapore (AVA) will help fish farmers affected by the recent fish deaths to recover and restart their farms, it said in a statement.

It is also working with external agencies and experts to explore solutions to minimise the impact of plankton bloom.

Late last month, many local fish farms in Changi near the East Johor Straits were affected by plankton bloom. The farms suffered massive fish deaths as a result.

Minister of State for National Development and Defence, Dr Maliki Osman, visited two of the affected fish farms on Thursday.

He said he sympathised with the fish farmers who are affected by the recent incident, but learnt that one farmer who took early action was able to save his fish and minimise losses significantly.

AVA said it sent out an alert to fish farmers in the area on Feb 16 and 17 to warn them about elevated plankton levels and to take the necessary precautions.

"Mr Gary Chang told me that he started preparing for a possible plankton bloom once he was alerted to elevated plankton levels. He lined his net-cages with canvas and installed a simple filtration system to maintain the water quality," Dr Maliki said.

"Other farmers also took measures, but unfortunately suffered severe losses as they may not have done so early enough."

Plankton found in seawater can multiply quickly in a very short period of time, and plankton bloom can be triggered by unpredictable weather, higher concentrations of nutrients in the sea water and poor water exchange during high and low tides.

Said Dr Maliki: "Plankton bloom occurrences are very difficult to prevent, but it is possible to reduce the impact. Whilst we provide assistance to help farmers tide over this difficult period, it is also important for farmers to do their part to take mitigating measures early."

AVA is also looking into how to build up farmers' resilience against such incidents. This includes putting in place robust contingency plans and conducting contingency exercises, he added. "We will also ask those who have taken early action to share their experience with other farmers."

Following a similar episode of plankton bloom last year, AVA started to work with the Tropical Marine Science Institute at the National University of Singapore to conduct studies on plankton bloom. The studies are still ongoing.

AVA also called for proposals for closed-containment aquaculture systems for coastal fish farming last year.

The agency recently awarded the tender to five companies to develop a more sustainable sea-based farming system that will minimise exposure to environmental changes, such as plankton bloom.

AVA CEO Tan Poh Hong said: "The proposals from the companies are promising... We hope that the projects can bring about significant improvements to boost the resilience of fish farming."