Towards the end of the 20th century, one of the most popular types of bird scarers used by farmers in Europe and America to protect their crops were the LPG powered gas guns, sometimes called also as bird bangers or bird scaring canons, which produced a periodic loud explosion.

These stationary guns utilize the explosive power of LPG / Propane gas ignition to create a loud shot-like sound to scare away the birds and predators. The volume of the noise depends on size of the canon and sometimes it is also adjustable. The interval between detonations can be adjusted from eg 40 seconds up to 30 minutes. 

The mechanism is simple. A carefully-controlled mixture of air and LPG / Propane or Butane is periodicall blown into a semi-open pot, which is the combustion chamber.

LPG powered scare guns can keep birds away from every kind of fruit and vegetable fields, in fish farms against herons, in airports with planes taking off and landing, from garbage disposal sites (for hygienic reasons), or from structures, buildings, roofs etc. where bird excrements can cause damage. In some parts of the world they can also be found employed as a scare to keep away elephants, monkeys, wild boars and other wild animals from destroying agriculture harvest and other vegetation.