The national water agency Public Utilities Board shared in a Facebook post on Monday (7 January) that 140 stingrays were removed from the reservoirs waters with the assistance of NUS and NParks after sightings on 20 Dec last year.
The authority has also stated that the fishing grounds have re-opened at Lower Peirce Reservoir on the same day and urge the public to continue to exercise caution and not to enter the waters while fishing.
"As bottom dwellers, stingrays are able to camouflage well against the reservoirs beds, making them hard to spot," it noted.
According to the agency, these stingrays can also breed in large numbers, hence it is an ongoing process to remove them.
Earlier in December last year, the authority announced the removal of 75 stingrays from the reservoirs and waterways since 2015.
PUB then urges members of the public to call PUB at 1800-Call-PUB (1800 2255 782) if a stingray were seen for assistance.
PUB stressed that it will continue to monitor the situation and conduct regular checks along Lower Pierce Reservoir, noting that the fishing grounds at Upper Seletar Reservoir will remain closed until further notice.
It also remind everyone that it is an offence to release any animal or fish into the reservoirs and waterways, as it may impact the water quality of water sources, and pose a risk to users of waterbodies.
A man was fined S$2,600 after he released three Motoro stingrays into Lower Seletar Reservoir in 2017.
However, the agency did not mention the next step they do to the stingrays and some members of the public questioned this.
Yew Hui Poa wrote, "I hope they were sold. Such a waste of life and money if they were just killed and disposed of, as the government usually does."
Wesley Gu wrote, "What was done with the captured rays?"
Meanwhile Mr Raistlin Ong Chun Kiat advised the agency on what can be done.
He wrote, "Good effort PUB. But why not rope in fishermen to help control as well as do studies on the ecological state of the waters. Many well managed waterways around the world do that.
Proper training and licensing of volunteers would help. Not to mention there would be many that are willing to volunteer their time for fishing, tag and release studies or even capture exercises. That's a lot of savings on tax expenditure there."