On Sun, 22 Oct 2000, allan benson wrote:
> Does anybody have any suggestions on how to avoid road kills? I seem to
> remember something about a whistle that is attached to the bumper bar on
> birding -aus some time ago. Has any body any experience with with this
> device? Does it work or does the noise drive you crazy?
These devices are widely sold in the US as "deer whistles" and they must
be available in Australia because our car had one affixed when we bought
it second-hand.
Air flowing through these devices supposedly produce a loud ultrasonic
whistle which alerts/frightens animals which would otherwise collide
with your vehicle.
However, all the functional analyses and the experimental tests I've
seen reported (from the US) suggest these device do not work.
I've seen claims these devices prevent collisions with birds, but this is
very unlikely as physiological tests of bird hearing suggest few species
can hear ultrasound. The highest frequency most birds can hear seems
to be similar to or significantly less than humans.
On a similar topic, quite reputable companies (e.g Dick Smith) sell
devices in Australia for home power-points which supposedly deter pests
either with ultrasound or electromagnetism or both. I've never seen any
evidence that these are effective and its implausible that ultrasound
could deter, fleas, for example, let alone a wide range of insects.
Andrew Taylor
Birding-Aus is on the Web at
www.shc.melb.catholic.edu.au/home/birding/index.html
To unsubscribe from this mailing list, send the message
"unsubscribe birding-aus" (no quotes, no Subject line)
to
|
