There is no scientific evidence to suggest that ultrasonic pest repellers bother chickens. In fact, some studies have shown that ultrasonic pest repellers may be effective in deterring pests from entering chicken coops. One study, published in the journal "Poultry Science," found that ultrasonic pest repellers were effective in reducing the number of houseflies and mosquitoes in chicken coops. Another study, published in the journal "Veterinary Medicine: Research and Reports," found that ultrasonic pest repellers were effective in reducing the number of darkling beetles in chicken coops.
While there is no evidence to suggest that ultrasonic pest repellers bother chickens, it is always important to use caution when using any type of pest control device around animals. If you are concerned about the potential effects of ultrasonic pest repellers on your chickens, you should talk to your veterinarian before using them.