During last Saturday's overcast morning, a group of Jurong residents walked around the Japanese Garden park, peering into bushes and around trees at the edge of ponds to look for herons.
They were among 200 volunteers who showed up at more than 70 spots around the island to track down the distinctive big birds as part of the National Parks Board's (NParks) ongoing Heron Watch project.
It asked members of the public to collect data on how many herons there are here and where they appear in a bid to help NParks design research projects and save habitats.
Such "citizen science" initiatives are gaining ground. NParks National Biodiversity Centre director Lena Chan said that beside Heron Watch, volunteers have also collected and photographed marine organisms for Singapore's first marine and shore life census.
Meanwhile, nature interest groups have been keeping track of birds, butterflies and seagrass - the only flowering plant to grow under water. Schools have also helped by counting plants and animals around their campuses.
Undergraduate David Tan, 25, who collects bird carcasses to build a genetic database of local species for the Avian Genetics Laboratory at the National University of Singapore, even counts on the public to call him when they spot a dead bird.
"The everyday layperson is a much better spotter of birds than I am because I'm always cooped up in the lab," he said.
The Internet has also opened up new ways to collect and analyse data. NParks is asking people to post their photos of flowering plants, along with their location, in a Facebook album called Singapore Blooms.
In February, a group of botanists and enthusiasts started a Singapore Flowering Facebook page to document the mass flowering triggered by the recent dry spell.
Botanical researcher Adrian Loo, 42, who started the page, said: "It was to get people excited about flowering and also to gather as much info as possible from different parts of Singapore."
Since 2005, NUS senior lecturer N. Sivasothi has gone online to solicit public sightings of animals such as rare moths, civet cats, otters and red junglefowl. To researchers' surprise, he said, public reports revealed that "red junglefowl must be all over the island".
In future, low-cost sensors or smartphone apps could be used by people to collect natural data around the world, the science journal Nature reported last month.
But ultimately, said Mr Sivasothi, researchers have to verify the sightings. And the locations of sightings are not published if researchers think people might poach or harm species, he added.
Still, with clear, detailed instructions, he said, "People can do pretty amazing things."
And get to experience something new.
Construction consultant Tai Yoon Cheng, 44, took his wife and young son to Saturday's Heron Watch session. "We've always joined the residents' committee activities, but this is our first time birdwatching."
This article was published on April 7 in The Straits Times.
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