Communications – electrical: acoustic wave systems and devices – Transmitter systems – Animal control
Patent
1986-10-07
1988-09-06
Tarcza, Thomas H.
Communications, electrical: acoustic wave systems and devices
Transmitter systems
Animal control
H04B 102
Patent
active
047697946
DESCRIPTION:
BRIEF SUMMARY
DESCRIPTION
The invention relates to a method and a device for scaring birds by discontinuous emission of acoustic, frequency-modulated signals of limited duration.
An electronic device for simulating scaring, warning or mating calls of animals is known from the German Patent No. 12 60 855. According to this patent, the animal sounds are synthetically generated from the frequency spectrum of pulse-controlled audio generators. The frequency of repetition of these animal sounds is controlled by clock pulses. By electronic conception of the device, it is possible to program various animal sounds, so that habituation of the animals to the very same sounds is prevented. In addition, a method of scaring rats and mice is described in the German Patent Application (OS) No. 20 22 056. In this case, the place where the animals stay is irradiated with ultrasonic sound of a specific level, which is periodically frequency-modulated within a given ultrasonic frerquency range. None of the conventional methods, however, is suitable for the protection of farming areas, such as fruit plantations and cornfields, of fishfarming ponds or of waste dumps, for the purpose of scaring birds, in particular starlets, gulls and common herons. The birds get used to the conventionally frequency- and/or amplitude-modulated acoustic signals in the range of audibility within a relatively short period of time, so that effective application of such devices is no longer ensured. The devices generating ultrasonic signals do not have a permanent birdscaring effect.
The object of the present invention therefore is to develop a method which permits effective bird scaring for indefinitely long periods of time. The bird-scaring device to be implemented should operate off the line and be characterized by lower power consumption and simple and low-cost design. In addition, the device should be adaptable to various species of birds.
According to the invention, this object is reached by generating at least two signals whose frequencies are periodically modulated within a range from about 30 to 9000 Hz, the modulation period being between about 0.01 and 5 seconds, said two signals differing in the frequency modulation range, in the modulation period and/or in duration, the individual signals being emitted either in fixed or in arbitrary sequence. Advantageous embodiments of the method according to the invention are defined in Subclaims 2 to 7.
The bird-scaring device according to the invention is provided with a sequencing control which permits the duration and/or the sequence of signals to be emitted to be determined and which controls a signal generation unit with frequency modulation equipment. The Subclaims 9 to 12 describe preferred embodiments of the device according to the invention.
It was found that audible acoustic signals which are frequency-modulated in a known manner are not suitable for scaring birds, even if these are emitted as a sequence of differently modulated signals. The birds get used to these sounds or to the sequence of their emission within a relatively short period of time, so that a scaring effect can no longer be achieved. The method according to the invention, on the other hand, generates signals which are modulated within a specific frequency range and which show a specific modulation period. It appeared that, surprisingly, neither a fixed nor an arbitrary emission sequence of such signals leads to habituation. An essential feature is that more than two, e.g. 16 to 32 of such signals are generated, which differ in three of their parameters, i.e. in frequency modulation range, in modulation period and/or in duration. This permits a plurality of variations. In addition, it is possible arbitrarily to vary the interval between two successive signals. According to the invention, the interval between the individual signals can be between 20 seconds and 1 hour, preferably between 1 and 30 minutes, in particular between 5 and 20 minutes. Each of the signals should be frequency-modulated preferably between 100 and 7000 Hz, in parti
REFERENCES:
patent: 3683113 (1972-08-01), Stewart
patent: 4105992 (1978-08-01), Luciano
patent: 4219884 (1980-08-01), DeSantis
patent: 4284845 (1981-08-01), Belcher
Beuter Karl
Weiss Rainer
Battelle - Institut e.V.
Lobo Ian J.
Tarcza Thomas H.
LandOfFree
Bird-scaring method and device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Bird-scaring method and device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bird-scaring method and device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1611095