Date: Mon, 23 Nov 1998 17:45:45 GMT
Reply-To: Jim Ferrari <email@example.com>
Sender: Georgia Birders Online <GABO-L@UGA.CC.UGA.EDU>
From: Jim Ferrari <jferrari@POST.WESLEYAN-COLLEGE.EDU>
Organization: Wesleyan College
Subject: predatory birds
The recent discussion of heat-seeking in barn owls reminds me of another
extraordinary (and well documented) case of the super-sharp senses of predatory
birds . . .
There was an article published in Nature (1995) about the ability of European
kestrels to see in the ultraviolet range, enabling them to detect the urine and
feces of the voles they prey upon. Kestrels can therefore assess the local
population density of voles without having to see a single one, enabling them
to focus their hunting efforts on only the most productive grounds. Pretty
amazing stuff to those of us still relying on just the usual, run-of-the-mill
wavelengths of light.
While the heat-seeking ability of barn owls has not apparently been
demonstrated (based on the recent discussion), at this point I wouldn't be
surprised to learn that they did a *DNA analysis* of their prey while perched
on a distant limb, the better to prepare themselves for a snack of vole, rat,
or mouse! Wonders never cease!