Michael and Tweeters,

Some information on the frequency range of hearing in birds is given in "The
Life of Birds" by Welty (3rd ed., 1982). He lists 10 species, in 8 different
families, whose hearing has been tested. For these 10 species, the upper
limit of hearing varies from 7.5 to 18 kilohertz (all below the ultrasonic
range), except for the Chaffinch, which could apparently hear up to 29
kilohertz.

It's interesting if Turkeys can hear ultrasonic frequencies, because
Ring-necked Pheasants, with an upper limit of 10.5 kilohertz, apparently
can't. There is certainly a wide range in the upper frequency limit of
hearing in different bird species.

Wayne C. Weber
Delta, BC
contopus at telus.net





-----Original Message-----
From: tweeters-bounces at mailman1.u.washington.edu
[mailto:tweeters-bounces at mailman1.u.washington.edu] On Behalf Of Michael
Dossett
Sent: February-06-08 9:22 AM
To: Tweeters at u.washington.edu
Subject: [Tweeters] ultrasonic hearing in birds

I can't say I know whether most birds can or can't hear ultrasonic
frequencies. I was intrigued by Wayne's statement and am curious about
references to which birds have been tested. One bird that I do know can
hear ultrasonic frequencies are turkeys. Many turkey hunters use ultrasonic
dog whistles to make Wild Turkeys "shock gobble" (Male turkeys gobble in
response to just about any loud or startling noise during the spring
courtship), in part because it is so effective and also in part because it
is a quieter alternative to the owl and crow calls which are typically
marketed for that usage. As a young boy growing up in Missouri, I was an
avid turkey call collector (though never a hunter) and got one of these just
because I was intrigued about the claims. I can say from first hand
experience that it works. Every time that I've blown it and had a turkey in
sight, the immediate response of the bird has always been to lift its head
and look around if
it is feeding, or to gobble if it is strutting.

Bats too can definitely hear ultrasonic frequencies but how that might deter
them or mess up their navigation and feeding behaviors I'm not sure...

Michael

Michael Dossett
Corvallis, Oregon
www.Mdossettphoto.com
phainopepla at yahoo.com