SINGAPORE — Scores of dead fish have been found again — this time at Sungei Buloh Wetland Reserve near the West Johor Straits.

The mysterious deaths come two months after 160 tonnes of fish from fish farms on both the East and West Johor Straits were found dead and washed up at parks and on beaches. Low levels of dissolved oxygen in the water, a plankton bloom or both, as well as the hot weather, had been fingered as the cause then.

A plankton bloom was, however, not detected yesterday, said a joint statement from the Agri-Food and Veterinary Authority (AVA) and the National Parks Board (NParks) in response to TODAY’s queries.

NParks staff noticed the dead fish in the morning. When AVA inspectors visited coastal fish farms in the West Johor Straits, none were found to have been affected. The inspectors also did not detect abnormalities there, such as mass mortalities.

The AVA said it is monitoring the situation closely, while NParks said it would be removing the dead fish at Sungei Buloh Wetland Reserve.

The authorities did not give an estimate of the number of dead fish in the area.

The AVA also said it conducts regular inspections of fish farms for compliance with licensing conditions, which include requiring the farms to ensure waste generated from farming operations is properly disposed in approved waste containers on land.

For the West Johor Straits, a skip tank and bins at Lim Chu Kang Jetty are designated as waste collection points.

“The AVA has been working closely with local farmers to encourage good farm practices, including proper waste management. In addition, we work with relevant agencies to detect illegal dumping of waste into the sea by fish farms. We will take enforcement action if farms are found to be disposing their farm waste into the water,” said the AVA. Kok Xing Hui