GB2531059A - Bird scaring apparatus - Google Patents

Abstract

A bird scaring apparatus 10 comprises a plurality of loudspeakers 17, and a signal controller 22 that is arranged to cause the loudspeakers to generate a bird scaring sound at intervals, and is arranged to vary the sound with time by: (a) varying the loudness of the bird-scaring sound; and also (b) generating the sound with only a selection of the loudspeakers rather than all the loudspeakers and changing the selection of loudspeakers during the generation of the bird-scaring sound. The bird-scaring sound may be a distress call of the bird species that is to be scared. Varying the loudness of the sound ensures that birds at a variety of different distances from the apparatus will hear the bird-scaring sound at an appropriate volume. Changing the selection of loudspeakers gives the birds the impression that a predator is moving around. The combination of these ways to vary sound is therefore beneficial in scaring and dispersing birds in a humane fashion.

Description

Bird Scaring Apparatus The present invention relates to a bird scaring apparatus that may be used to disperse birds that have landed in an area, or to prevent birds landing in an area.

There are many situations in which scaring or dispersing of birds is desirable. This may apply in agricultural or market-gardening situations, in which birds may be eating a crop; in urban environments in which birds cause fouling of buildings; in seaside environments in which birds may mob people to seize food, or cause fouling on boats; or at offshore oil rigs, where birds may be a hazard for incoming helicopters; or at airfields in which the impact of a bird with an aircraft, sometimes referred to as a bird strike" poses a risk to the aircraft and its passengers as it may for example disable an engine. A vahety of different approaches have been used to scare or disperse birds. In some cases a trained bird of prey such as a peregrine may be flown by a falconer to disperse birds, but this is not appropriate for continuous use. In an agricultural situation it is widely known to use a scarecrow, i.e. an imitation person, and in other contexts it is known to use a model of an owl or a bird of prey. In some agricultural contexts gas-powered guns are installed that generate intermittent explosive bangs, reminiscent of a shot gun. Another approach is to produce an electronically-generated or electronically-stored bird-scaring sound such as a distress call, the call of a predatory bird, or another bird-frightening noise (which may be audible, or may include frequencies outside the audible range).

It has been found that there can sometimes be problems with such bird-scaring devices, because birds may get used to the presence of static scaring devices, or may get used to the artificial noises particularly where a static device is used regularly.

According to the present invention there is provided a bird scaring apparatus that comprises a plurality of loudspeakers, and a signal controller, wherein the signal controller is arranged to cause the loudspeakers to generate a bird-scaring sound at intervals, and is arranged to vary the sound with time by: (a) varying the loudness of the bird-scaring sound; and also (b) generating the sound with only a selection of the loudspeakers rather than all the loudspeakers, and changing the selection of loudspeakers during the generation of the bird-scaring sound.

In one embodiment of the bird-scaring apparatus the bird-scaring sound is an electronically-generated or electronically-stored distress call of the bird species that is to be scared. Since this is the natural and usual distress call of the bird species, the birds do not become habituated to hearing it, and naturally associate it with the presence of a predator.

It will be appreciated that the distress call refers to a call made by that species of bird when it is in distress; it is to be distinguished from an alarm call, which is a more general warning that a threat such as a predator may be present. While the alarm call may represent "look out", the distress call represents "I am being attacked -escape if you can". As another option the bird-scaring sound is an electronically-generated or electronically-stored call of a predatory bird.

Varying the loudness of the sound ensures that birds at a variety of different distances from the loudspeakers will hear the bird-scaring sound at an appropriate volume.

Changing the selection of loudspeakers gives the birds the impression that the bird-scaring sound is coming from different places, implying that a predator is moving around. It is therefore beneficial to vary the sound in both of these ways.

In one embodiment the loudness of the bird-scaring sounds is arranged to vary continuously from a minimum to a maximum, and then back again. This gives the impression of the predator moving, and it ensures that at some stage, no matter where the bird is standing, the distress call will be at a natural level and apparently getting closer to the bird.

The loudspeakers may be mounted in a single housing, or in housings that are immediately adjacent to each other, for example a single housing may enclose loudspeakers facing in for example three different directions, or in six different directions.

Such a housing may also include the signal controller. The different directions may all be in a common plane, for example all being horizontal; and the angles between the directions of adjacent loudspeakers may for example be between 45° and 90°, for example 60°.

Alternatively the loudspeakers may be in separate and distinct housings which may be spaced apart from each other. For example there might be loudspeakers in 10, 20 or even separate housings, which may be spaced apart, and may communicate with the signal-controller wirelessly or with cables, or alternatively they may be a plurality of separate signal-generating sources actuating individual loudspeakers or groups of loudspeakers, the separate signal-generating sources communicating with a central signal controller wirelessly or with cables. Where wireless communication is used, this may be via Bluetooth, radio signal control, or using mobile phone technology, for example.

The duration of the sound is preferably less than two minutes, and may for example be 90s or 60 s. The intervals between successive sounds used to scare or disperse a particular species may be random, or regular, and the intervals may for example be between 30 minutes and 90 minutes. The intervals may be shorter, for example as short as minutes, if the species is particularly loath to disperse, but it is preferable not to use such short intervals for more than about a day or two, as the birds may become accustomed to frequent sounds.

Operation may be automated, so as to function either only during the day, including twilight, or only during the night, or continuously. For example the apparatus may incorporate a light sensor to detect dawn and dusk. The apparatus may also include a bird sensor, such as an infrared sensor, and be actuated when a bird is sensed in the vicinity.

The apparatus may also include the facility for actuation by an operator.

The apparatus may be powered by a battery or by mains electricity, or may be powered by a battery in conjunction with a solar panel so as to be self-contained. The apparatus may be freestanding, or may be mounted on a building, or mounted on a vehicle so it can be used in different places.

It will be appreciated that the apparatus of the invention is humane, and does not endanger the lives of the birds. Furthermore natural bird calls that are played back at a natural sound level are not intrusive, and may remain unnoticed in places where the public is present.

The invention will now be further and more particularly described, by way of example only, and with reference to the accompanying drawings in which: Figure 1 shows a perspective view of a bird scaring apparatus of the invention; Figure 2 shows a schematic circuit diagram for the bird-scaring apparatus of figure 1; Figure 3 shows a perspective view of an alternative bird scaring apparatus; and Figure 4 shows a perspective view of a modification to the apparatus of figure 3.

Referring to figure 1, a bird scaring apparatus 10 includes a base plate 12 supporting an upright pole 13. Mounted on the pole 13 at about 1 m above ground level is a housing 15 which contains electronic circuitry described below, and at the top of the pole 13 is mounted a solar panel 16 connected electrically to electronic circuitry 20 (see figure 2) in the housing 15. In this example the housing 15 is hexagonal in plan view, with six upright faces, and mounted in each upright face is a loudspeaker 17 (only three are shown). In addition a passive infrared (PIR) sensor 18 is also mounted each upright face of the housing 15, and a light sensor 19 is mounted on the top face of the housing 15.

Referring now to figure 2, this shows a schematic circuit diagram of the electronic circuitry 20 of the apparatus 10. The circuitry 20 includes a signal controller 22 powered by a battery 24 which is kept charged by the solar panel 16. The signal controller 22 is connected to each of the loudspeakers 17, and to each of the FIR sensors 18, and to the light sensor 19. In addition it is connected to a memory 26, and to a control panel 28. The control panel 28 may be mounted in one face of the housing 15, or it may be a separate item connectable to the housing 15 by a cable.

The memory 26 contains electronic recordings of distress calls for a selection of different species of birds. For example for use in Europe a suitable set might be herring gull, black headed gull, rook, crow, starling and feral pigeon, but other potential species include mallard, oystercatcher, lapwing, grey partridge, sand martin, house sparrow, blackbird, jackdaw and magpie; for use in North America a suitable set might include American kestrel, Canada goose, double-crested cormorant, arctic tern, bluejay, red-winged blackbird, great blue heron and killdeer; while in Australia additional appropriate species might include white ibis, silver gull and myna. The apparatus 10 has been found to be effective with all of these species, and with a number of other species also.

The apparatus 10 is set up in a location from which birds are to be dispersed, for example a farmer's field, a town square, a warehouse, or an offshore oil rig. The memory 26 would be set up to contain an appropriate selection of distress calls suited to the area where the apparatus 10 is to be used. The signal controller 22 is programmed by an operator, using the control panel 28, to indicate the species of birds that are to be dispersed, and the distance from the apparatus 10 over which the species are to be dispersed. The output audio power from the loudspeakers 17 may for example have a maximum of 25W, which may be suitable for dispersing birds over a distance of up to about 120 m; in practice the distance may be set to a maximum of for example 100 m or7O m. The signal controller 22 may be programmed to operate continuously, or to operate only when birds are detected by one of the PIR sensors 18; and may be programmed to operate continuously day and night, or only during daytime and twilight (say about one hour after sunset or before sunrise) in response to signals from the light sensor 19.

When operating, the signal controller 22 causes the loudspeakers 17 to produce a suitable sound at intervals, i.e. producing sound for a brief period and then ceasing for an interval typically between 30 mm and 90 mm, more preferably between 45 mm and 75 mm.

The interval may be selected randomly within such a range. If for example the signal controller 22 has been programmed to disperse a number of different species, for example lapwings, herring gulls and rooks, then the loudspeakers 17 would be arranged to produce the appropriate sounds in succession: to produce lapwing distress call for a brief period; and then after a gap of no more than 2 minutes, e.g. a gap of 60 s, produce a herring gull distress call for a brief period; and then after another gap of no more than 2 minutes, produce a rook distress call for a brief period. That is to say the appropriate sounds for dispersing the different species are produced in succession, with brief gaps between them.

After the succeeding quiet interval the appropriate sounds are then produced again, optionally in a different sequence. While each such sound is being produced, the volume is varied up to that corresponding to the previously set maximum distance and then varied down again. So for example the volume may be varied starting at that corresponding to say m, increasing to that corresponding to 70 m, and then decreasing back to that corresponding to 20 m.

At any one time only some of the loudspeakers 17 are energised, that is to say the loudspeakers 17 are not all energised at once. For example the six loudspeakers 17 may be connected to three output channels: A, B and C. Whilst producing the sound to disperse a particular species, the channels are varied. For example in the case described above, the lapwing distress call might be produced for a period in the range 30 s up to 60 s through the loudspeakers 17 connected to output channel A, and then for a period in the range 30 s up to 60s through the loudspeakers 17 connected to output channel B, and then for a period in the range 30 s up to 60 s through the loudspeakers 17 connected to output channel C. This gives the impression that the sound is coming from different places.

Alternatively, with the six loudspeakers 17 connected to the three output channels A, B and C as described above, the lapwing distress call might be produced for a short period in the range 30 s up to 60 s through the loudspeakers 17 connected to output channels A and B, and then produced for a short period in the range 30 s up to 60 5 through the loudspeakers 17 connected to output channels B and C. Thus during the period of time when a sound is being produced to scare a particular species of bird, the volume of the sound is varied, and the set of channels A, B and C through which the sound is produced, and so the selection of loudspeakers 17, is also varied. The effect of both of these variations is to confuse the bird as to where the apparent predator is located, and the birds typically then flee the area. It has been found that some species, e.g. lapwings and starlings, tend to disperse straightaway as a result of hearing their distress calls produced in this fashion. Other species, e.g. corvids, tend to fly initially towards the source of the sound, and then fly away.

It has been found that the distress calls for some species, e.g. crows, may also cause other species to disperse. Furthermore, where there is a mixed flock containing different species, then scaring and dispersing one of those species may well cause the other species to leave also. For example if feral doves are present with a flock of gulls, then a distress call that causes the gulls to leave will typically cause the feral doves to leave in response.

Although as described above the sound used to disperse a particular species is the distress call of that species, this is not always feasible. For example swallows do not appear to have an identifiable distress call. In such cases a different sound may be used, for example the call of a bird of prey. As described above, while producing this sound the volume would be varied, and the selection of loudspeakers 17 through which the sound is produced would also be varied.

It will be appreciated that the apparatus 10 described above may be modified in various ways. For example it might include only three loudspeakers 17, one for each channel A, B and C, which may be arranged to face to the left, to the right, and straight ahead, so the directions differ by 60° (as is the case in the hexagonal housing 15 described above); such a three-loudspeaker apparatus would be suitable for installing up against a wall.

Referring now to figure 3 there is shown an alternative bird-scaring apparatus 30 which has a number of features in common with the apparatus 10; identical features are referred to by the same reference numerals. The apparatus 30 comprises a base unit 32, and several separate loudspeaker modules 34 (six are shown) connected to the base unit 32 by cables 35, each loudspeaker module 34 including a loudspeaker 17. In this example the loudspeaker modules 34 are in the form of rectangular boxes, which may stand on the ground. Although all the loudspeaker modules 34 are shown as facing in the same direction, they may alternatively be arranged facing in different directions. The base unit 32 in this example is of a generally rectangular box shape. A passive infrared (PIR) sensor 18 is also mounted on each upright face of the base unit 32, and a light sensor 19 is mounted on the top face of the base unit 32. A control panel 28 is mounted in one face of the base unit 32.

The base unit 32 contains electronic circuitry substantially identical to the electronic circuitry 20 shown in figure 2, although the number of PIR sensors 18 is different. The apparatus 30 may include a solar panel 16 (not shown) or altematively it may be powered for example by mains electricity. The loudspeakers 17 are connected to three different channels A, B and C, as described above. The apparatus 30 operates in substantially the same way as described above. However, the much greater separation between the loudspeakers 17 that are associated with the different channels A, B and C provides a significantly greater stereo sound effect when the sound changes from channel to channel.

Thus, as described above, when operating, the signal controller 22 causes the loudspeakers 17 to produce a suitable sound at intervals, i.e. producing sound for a brief period and then ceasing for an interval typically between 30 mm and 90 mm, more preferably between 45 mm and 75 mm. When a sound is being produced to scare a particular species of bird, the volume of the sound is varied, and the set of channels A, B and C through which the sound is produced is also varied. The effect of both of these variations is to confuse the bird as to where the apparent predator is located, and the birds typically then flee the area.

It will be appreciated that the apparatus 30 may be modified by providing wireless communication between the base unit 32 and the separate loudspeaker modules 34, instead of the wires 35. Furthermore there may be a different number of loudspeaker modules 34, and a different number of loudspeakers 17, for example there may be as many as twenty or thirty loudspeakers 17. Furthermore, the number of channels may differ from that described above, for example there might be four or even five channels. For example there might be twenty loudspeakers 17 connected to four different audio channels, with five loudspeakers to each channel.

Referring now to figure 4 there is shown a bird-scaring apparatus 40 which is a modification to the apparatus 30; identical features are referred to by the same reference numerals. The apparatus 40 comprises a base unit 42, and several separate loudspeaker modules 44 (nine are shown) connected to the base unit 42 by cables 35, each loudspeaker module 44 including a loudspeaker 17. In this example each loudspeaker module 44 is horn-shaped. A light sensor 19 is mounted on the top face of the base unit 42. A control panel 28 is mounted in one face of the base unit 42. (The base unit 42 differs from the base unit 32 in that it does not include any passive infrared sensors 18.) The modules 44 may for example be supported on posts (not shown) or may rest on the ground.

The bird-scaring apparatus 40 operates in the same way as described above, except that each channel A, B and C is connected to three loudspeaker modules 44. The base unit 42 includes a signal controller 22 (not shown in figure 4), and during operation the signal controller 22 causes the loudspeakers 17 to produce predetermined sounds at intervals, such as a distress call of a particular species. While a sound is being produced to scare a particular species, the volume of the sound is varied, and the set of channels A, B and C through which the sound is produced is also varied, as described above. The effect is that the birds typically then flee the area.

The apparatus 10, 30 or 40 may include the facility for an operator to initiate the sound production, as may be advantageous for example during maintenance, rather than having to wait for the next automated sound production to occur. An operator may initiate sound production using the control panel 28. Alternatively the signal controller 22 may be connected to or may incorporate a sensor (not shown) so that an operator may use a remote trigger, for example using infrared or wireless technology, to initiate sound production. The remote trigger may provide multiple functions, and so may be able to take the place of the control panel 28. For example it may be possible to use the remote trigger to select bird species; to adjust the range of audio volumes (corresponding to the range of distances over which birds are to be scared); and to adjust the mean value of the intervals between successive productions of the sound.

The sound production process described above, in which the intervals between successive productions of sound are typically in the range between 30 minutes and 90 minutes, more preferably between 45 minutes and 75 minutes, and may be selected randomly within such a range, is suitable for normal operation. If the birds are proving particularly difficult to disperse it may be found beneficial to alter the mode of operation, so that the sound production occurs at briefer intervals, although preferably no shorter than 15 minutes. By way of example the apparatus 10, 30 or 40 may be operable in three different modes: normal operation; enhanced operation; and extreme operation. The operation in the latter two modes differs from that in normal operation only in the duration of the intervals, which are progressively shorter. For example in normal operation sound may be produced at a time interval selected randomly between 45 minutes and 75 minutes; in enhanced operation the time interval may be between 30 minutes and 50 minutes; and in extreme operation the time interval may be between 15 minutes and 25 minutes. Since sounds that are produced too frequently may become ignored, operation may automatically revert to normal operation after a pre-set period such as 4 hours, 8 hours or 24 hours. It will be appreciated that initiating operation in a mode other than normal operation (i.e. in enhanced operation or in extreme operation, in this example) may be done by an operator using the control panel 28, or may be initiated in a wireless fashion for example using a remote trigger as discussed above.

Other variations and modifications will be apparent to the skilled person. Such variations and modifications may involve equivalent and other features that are already known and which may be used instead of, or in addition to, features described herein.

Features that are described in the context of separate embodiments may be provided in combination in a single embodiment.

It should be noted that the term "comprising" does not exclude other elements or steps, the term "a" or "an" does not exclude a plurality, a single feature may fulfil the functions of several features recited in the claims. It should also be noted that the Figures are not necessarily to scale; emphasis instead generally being placed upon illustrating the principles of the present invention.

Claims (11)

1. Claims 1. A bird scaring apparatus that comprises a plurality of loudspeakers, and a signal controller, wherein the signal controller is arranged to cause the loudspeakers to generate a bird-scaring sound at intervals, and is arranged to vary the sound with time by (a) varying the loudness of the bird-scaring sound; and also (b) generating the sound with only a selection of the loudspeakers rather than all the loudspeakers, and changing the selection of loudspeakers during the generation of the bird-scaring sound.
2. 2. An apparatus as claimed in claim 1 wherein the bird-scaring sound is an electronically-generated or electronically-stored distress call of the bird species that is to be scared.
3. 3. An apparatus as claimed in claim 1 or claim 2 wherein the loudness of the bird-scaring sound is arranged to vary continuously from a minimum to a maximum, and then back again.
4. 4. An apparatus as claimed in any one of the preceding claims wherein the loudspeakers are mounted in a single housing, or in housings that are immediately adjacent to each other.
5. 5. An apparatus as claimed in claim 4 wherein the signal controller is within one such housing.
6. 6. An apparatus as claimed in any one of claims 1 to 3 wherein the loudspeakers are in separate and distinct housings which may be spaced apart from each other.
7. 7. An apparatus as claimed in any one of the preceding claims wherein the duration of the sound is less than two minutes.
8. 8. An apparatus as claimed in any one of the preceding claims wherein the intervals between successive sounds used to scare or disperse a particular species are between 30 minutes and 90 minutes.
9. 9. An apparatus as claimed in any one of the preceding claims that incorporates a light sensor to detect dawn and dusk.
10. 10. An apparatus as claimed in any one of the preceding claims that also includes an infrared sensor.
11. 11. A bird scaring apparatus substantially as hereinbefore described with reference to, and as shown in, figures 1 and 2, or figures 2 and 3, or figures 2, 3 and 4 of the accompanying drawings.