Lasers may soon be used to combat the noise and nuisance caused by wild birds roosting, with one trial conducted by the Agri-Food and Veterinary Authority (AVA) recently, though pest control firms expressed doubts about their usefulness.
The use of such Class 3A handheld laser devices by AVA officers is not meant to kill or blind wild birds such as Javan mynahs, pigeons and house crows. Instead, the laser beams are aimed around the birds to scare them away.
AVA said the trial was one of various mitigation methods it is testing.
With a power output of up to five milliwatts, Class 3A lasers are the most powerful type that do not require a licence to use, possess or import, according to the National Environment Agency website.
AVA was responding to questions after The Straits Times discovered a flight notice issued by the Civil Aviation Authority of Singapore cautioning airmen of a bird control trial being conducted in the Potong Pasir area from Sept 28 to Oct 1.
Residents in the area, including the private Sennett Estate, have complained about the noise caused by roosting mynahs in the trees there. AVA said it had received more than 10 complaints so far this year.
Lasers were brought into the picture after other efforts, such as the selective pruning of trees or regular disposal of food waste that may attract birds, did not pay off.
AVA said the use of lasers is not new here - they have been used to scatter birds at Changi Airport, and as part of AVA's other bird management trials.
The method is non-lethal, humane and has zero noise emission, and studies have shown that its effectiveness differs across bird species. Some species may become accustomed to the lasers following repeated application, AVA added.
But bird control specialists expressed scepticism about using lasers as a passive bird control measure, citing their own trials.
PestBusters chief executive officer Thomas Fernandez said his firm tested and gave up on bird control "laser guns" around five years ago.
"We were very eager and excited when we had our laser guns, but they just didn't work for us. We were able to affect a few crows, but it was not enough to get rid of them all," said Mr Fernandez.
These lasers, he added, are effective only for a while and when light levels are low enough for the beam to stand out.
Ms Gloria Ngoi, business development manager at bird control firm Mastermark, said Singapore also has tight regulations against the use of high-powered lasers, which limit the range of such handheld laser devices.
But while the lasers' effectiveness may be limited, Ms Ngoi said the trial allows AVA to add "another toy into the tool chest of available methods" used to manage bird issues.