Those noisy crested pigeons use their unique feathers to sound an alarm
FLIGHT AUTO PART silicon siren 12V DC -110 DB Police Siren Sound Plastic Security Alarm (Black Color, Medium) (Also for Bikes, Motorcycles and Cars) : Amazon.in: Car & Motorbike
Newbie question - unknown beeping/alarm in Airbus cockpit along with flashing letters on display (highlighted in pic) : r/flightsim