There is no evidence that I know of to suggest that birds are somehow
drawn to wind turbines, and plenty of evidence to the contrary.
Birds "can avoid large trees and other tall objects," but they don't.
See http://migratorybirds.fws.gov/issues/tower.html for a good
summary by the U.S. Fish and Wildlife Service of bird kills due to
collisions with a variety of structures. Many of these (buildings,
power plant smokestacks) have no associated magnetic fields.
Tom Gray
American Wind Energy Association
At 10:56 AM 12/27/2003 -0500, GJustice wrote:
I have been interested by the fact that these structures are presenting
such a great problem to avians. It seems counter intuitive that birds
would be challenged by structures like these, after all they can avoid
large trees and other tall objects. We know that most avians use
Magnetic field (as well as solar and geographic) orientation during
migration and are disrupted by minor fluctuations as low as those that
can be created by heavy deposits of Iron ore in a hillside or sunspots
(Gill, second ed. 1994). If we then think about the physics of turbine
generated energy and magnetic field dynamics associated with these huge
turbines mounted 100 / 200 feet in the air I think we can better
understand why birds fly into them. Although they may well be able to
avoid them during the day, on a dark night they could stand out like a
beacon. I haven't had much time to research this idea but I think I'm
going to spend some more time doing just that. If anyone else has any
references to papers published or studies done on artificial magnetic
field disruption and avian migration please let me know.
Good Birding
Greg Justice
gjustice@xxxxxxx
LeighTern@xxxxxxx wrote:
Why are windmills so hard on birds? I read the article in the post. Ididn't
find it very helpful. It didn't explain to me how or why windmills are moretowers ,
dangerous than any other tall structure ..........skyscrapper, radio
Cell phone facilitators etc etc.
W
William Leigh
Leightern@xxxxxxx
Winchester VA
