This device generates bird distress calls, digitally recorded calls of birds of prey and electronic harassment noises to keep the target birds away from crops, buildings and airports, … (everywhere where birds are a problem). Specifically designed to act against:

Laughing gull
Ring-billed gull
Herring gull
Iceland gull
Black-headed gull
Glaucous-winged gull
Double-crested cormorant
Hen harrier