Logging onto www. pigeonpatrol.ca you will find an assortment of Sonic and Ultrasonic Sound emitters selling or being released in January 2014:
Sonic sound emitters, are one of the most effective deterrents on the market. Consisting of a central unit together with a Tweeter, the system emits distress calls and calls of predators of the target species as well. Effective emitters randomize pitch, magnitude, time interval and other factors to prevent birds’ getting used to them.
Ultrasonic electronic devices produce high pitch emissions in ultrasound. The sound is designed to be too high pitched for people to hear, but audible to most birds. This has the advantage to preventing disturbance to neighboring households.
All of these units work well indoors and outdoors claims Pigeon Patrol
Products and Services, the Canadian leader in bird deterrent products and bird control. On their website www.pigeonpatrol.ca is loaded with vital information on how these units work. Areas of use would include hangars, warehouses, plants, tunnels, loading docks, boat houses, underpasses, storage sheds, barns, sports arenas, convention centers, parking garages and farmers fields.
Pigeon Patrol Products & Services sold hundreds of these units last year without a single unsatisfied customer or return.
The company also sells pigeon spikes or bird spikes, bird netting, bird lasers and a new gel called 4-S Gel.