A new laser scarecrow system has undergone further testing and study by researchers from the University of Rhode Island (URI) in the Northeastern United States in 2022, designed to deter birds from open fields in farms.
The system can scare away birds by producing bright, constantly moving green lasers across cornfields and other crops using 50-milliwatt laser emitters inside a bucket attached to a pole to prevent crop damage. It exploits the birds’ strong sense of sight and sensitivity to green.
Alongside traditional, physical scarecrows, farmers have used visual methods such as propane cannons and shotguns but had little effect, and farmers still reported losing as much as 75 percent of their crops to birds.
Rebecca Nelson Brown, professor of plant sciences from the University of Rhode Island and lead researcher in developing the laser scarecrow, devised the system as an alternative to other visual methods of repelling birds.
“Laser light prevents birds from perching on tops of corn tassels before moving lower to feed. Stopping them from perching on the tassels will make birds watching for flock mates move and relocate the whole flock,” said Brown.
As shown in previous research, lasers work best against flocking birds. These include blackbirds, geese, and gulls, which are the most affected by the technology. Crows, the most notorious species of bird that have caused damage to cornfields, have not yet been extensively tested against in the URI’s test field.
On the other hand, lasers are not effective in deterring mammals, and Brown has added that studies have shown that deer do not respond to lasers. Mammals generally detect threats through scent and sound.