SINGAPORE - Some 185 volunteers swept out across Singapore on Saturday morning, craning their necks for glimpses of egrets and herons, in the most comprehensive islandwide count of the birds here to date.
These long-necked, broad-winged birds can often be spotted pecking around in canals or flying overhead.
The National Parks Board (NParks) carried out Singapore's first heron count in a decade in an effort to get the public involved in monitoring nature's health here.
It roped in volunteer coordinator Wang Luan Keng, who has run similar surveys before.
Ms Wang, a trained ornithologist who runs nature education workshops, first started keeping tabs on the big birds in 2003 with the Nature Society, but the project fizzled out after a year.
At the time, she said, anecdotal sightings of birds and nests were in decline, and the situation today could be the same.
Herons are big and easy for beginners to identify. As winged predators that feed on fish, they are also good indicators of whether wetlands are healthy, she said.
Singapore has eight relatively common species, from the small squat Striated Heron to the kink-necked, yellow-beaked Cattle Egret.
Ms Wang added: "Nesting herons are sensitive to disturbance such as construction, fogging and any kind of habitat modifications.
"Constant harassing from fishermen, boats and sometimes photographers does not help. So there are fewer nesting colonies now."
It is not clear whether the perceived decline is due to habitat disturbance, or something in the water ruining their diet, she said. "We know too little about their ecology to make any conclusions."
The data from Saturday's count will tell NParks how big the populations are and where the different species live.
The survey will be repeated every few years to show how these patterns change over time.
Numbers from the count varied sharply.
Volunteer Kelvin Lee said he had "no luck" at Holland Woods along Clementi Road.
At Chek Jawa wetlands, there were just two herons, while at Sengkang Riverside Park, volunteers counted more than 200 - a surprise considering the amount of development in the area.
Ms Wang said: "With more watchful eyes, perhaps we will be able to locate more nesting colonies and hopefully provide some protection of the colonies before they are disturbed or destroyed."
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