Some neighbours of ours tried them but the effect wasn't long lasting. The
many orchards in the area use cannons that give a boom at irregular times
but that isn't practical in an urban setting for obvious reasons.

There are many cats in the area but they have proven to be next to useless
in bird control as they must be well fed and therefore not interested in
birds.

Thank you

Ron

"Robert Olin" wrote in message
...
I've had good luck with Bird Wire - the shinny tape that you can get in
the garden store. It kept peacocks off my porch where they used to perch
and protected my cherry trees last year. I used to lose most of my
cherry, but not now. I was told years ago it was the sonic hum it made
when you stretched it. It might also be the reflection moving around in
the breeze. It's cheap too.

--
Robert Olin
Bob's Water & Septic LLC

http://soilsandseptic.com/bobs.html

"dpb" wrote in message
...
Worn Out Retread wrote:
Does anyone have experience in using ultrasonic bird repellers? Do they
work or are they just a fancy gadget that actually does very little or
nothing?
...

HIGH FREQUENCY SOUND DEVICES LACK EFFICACY IN REPELLING BIRDS

WILLIAM A. ERICKSON1 and REX E. MARSH, Wildlife and Fisheries Biology,
University of California, Davis,California 95616.

TERRELL P. SALMON, Division of Agriculture and Natural Resources,
University of California, Davis, California 95616.

ABSTRACT: Ultrasonic or high-frequency sound-producing devices are
marketed as a scaring or frightening method for bird control. Although
inaudible to humans, most birds also do not hear in the ultrasonic
frequency ranges of above 20,000 Hz, thus the credibility of advertised
claims raises questions. A review of efficacy studies conducted and
published by a number of researchers fails to demonstrate the usefulness
of such bird control devices.

Proc. 15th Vertebrate Pest Conf, (J. E. Borrecco & R. E. Marsh,
Editors) Published at University of Calif., Davis. 1992

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