Scare Guns

Background

The EPA provide the following information relating to scare guns.

Under the EPA's Noise Control Guidelines, scare guns are defined as devices for producing a loud explosive sound for the purpose of scaring away birds from crops and orchards. Scare guns, also known as gas guns or scatter guns, produce an explosive noise by the ignition of a charge of gas and air.  Some scare guns rotate after firing so that the next blast is emitted in a different direction, which is intended to increase the surprise effect on birds.

Scare guns, when used as the sole bird deterrent, are likely to become significantly less effective after a few days.  This is due to the birds becoming accustomed to the noise. For scareguns to remain effective it is necessary to vary and enforce the frightening effect. Methods which do this include the relocating of the scare gun every day or so and the use of ‘birdfright’ explosive cartridges.

The rate of firing the scare gun must be carefully considered. If the firing rate is set too high, the birds will very quickly become accustomed to the noise. However, if set too low, the birds will return from cover after being frightened away and will have time to feed.

For the guns to be most effective they should be used when the birds are most actively feeding. This will normally be in the early morning and late afternoon; but this could be dependent on the species. Most scare guns can be fitted with a timer that enables them to be automatically turned on and off. Scareguns are not the only method of bird control available. Where scare guns cannot be used, other bird controls should be considered by the producer.

These include:

• kites, shaped like birds of prey
• chemical sprays that are unpalatable to some species of small birds
• plastic strips that hum in the wind
• nets and plastic mesh
• noise generators such as ‘Av-alarm’, ‘Pestaway Agricultural Noise Generator’ or a ‘white noise’ generator. (The first two produce a high level of noise which may cause annoyance to residents if living nearby.  The last-mentioned device produces a cicada-like sound and has been found to be particularly effective with silvereyes).

Discussion

Birds that attack fruit and crops can cause significant losses to a producer.  A scare gun, if used correctly, does offer some protection against this problem. However, the noise that frightens the birds can also cause significant annoyance to neighbours living in the area.

As a consequence, when scare guns are used, there needs to be a balance set between the producer’s needs and the rights of residents. This guideline attempts to set this balance and should be seen as a reasonable compromise for both parties.

Guidelines for the control of noise from scareguns

• A scare gun must not be used if the distance between the scaregun and any complainant's house is less than 300 m (See Note 2).
• The scare gun must not emit more than 70 blasts/day.
• The scare gun must not be used earlier than 7am or later than sunset. Earlier starting times will be allowed if this is agreed to by the neighbours/local residents.
• The total time of operation of a scare gun must not exceed 12 hours in any one day. However, the time of operation may be divided into two separate periods, provided the interval between blasts is not less than six minutes.
• The scare gun must be located as far away as possible from any neighbouring houses.
• Wherever possible, the shielding effects of natural features, buildings and so on shall be used to reduce the level of the blasts at complainants’ houses.
• Wherever possible, the use of the scare gun shall be minimised.

Notes:

• These guidelines are based on an average maximum level of 100 dB LIN Peak of the loudest 20 per cent of blasts measured at the complainant’s home when the weather favours noise propagation. The dB LIN Peak is measured with the sound level meter set to linear (‘Z’) frequency-weighting and peak (‘P’) time weighting.
• Where the level of the blast from a scaregun can be adjusted, then the distance between the scaregun and any complainant’s house may be less than 300 m. In this case the adjusting mechanism must be permanently fixed such that the average maximum level of the blasts at the house does not exceed 100 dB LIN Peak.
• Weather conditions affect the propagation of noise. Received levels are loudest when the wind blows from the source to the receiver.  Temperature inversions, which often occur in the early mornings after a clear night, also increase noise propagation.

Under the Environment Protection Act 1970, the Environment Protection Authority (EPA) are able to investigate noise from commercial, industrial and agricultural businesses. Council's Community Rangers are able to in investigate noise from residential premises.

Contacts

For more information on the Noise Control Guidelines for scare guns, please contact the EPA via telephone on 1300 372 842 or visit the EPA website.