Laser scarecrows to prevent birds from eating crops have been developed by a researcher from the University of Rhode Island. The same researcher has already tested it in various cultivated fields of the state and has ascertained the good level of yield compared to the classic scarecrows and above all compared to the propane cannons.
The laser emits green light, a color for which the birds are very sensitive, which automatically moves back and forth across the field scaring the birds even before they can reach the plants. It is made with relatively inexpensive LED lights and can also work with batteries. The latter can also be charged by solar panels.
Propane guns are effective but noisy, which, when cultivated fields are close to homes, can create problems. The laser scarecrows are instead completely silent while the beam they emit is not visible to humans in the light of the sun, as specified by Rebecca Brown, professor of plant sciences at the aforementioned university that invented the device.
This is not an absolute novelty: it is already for several years that lasers are used precisely to scare the birds but they are hardly used in agriculture as they are considered unsuitable, at least until the presentation of this new device; they are for example used in closed or partially closed environments such as stadiums or warehouses.
According to the researcher, the success of the device lies in the fact that the birds perceive the laser beam as a solid object from which it is necessary to stay away even if it has noticed that if the laser is fixed and does not move constantly, the birds tend to ignore it in the end. There are evidently biological-cerebral mechanisms that the researcher has not however analyzed given the fact that the device seems to work.