Does anyone have any experience using Sonic Pest Chasers? They say they are safe around humans, cats and dogs, but no mention of birds. The only "don't" on the package is for use around any rodents, such as hamsters, guinea pigs, rabbits, etc. I'm wondering if they are safe for use around chickens, and also caged birds, as I have a Cockatiel in the house. It says they emit high-frequency sound to repel rodents - sound pulsing 68 to 80 times a second at 100 dB. Thanx!