Ok, I promise this will be my only post on this... don't want you
bird-list-server types to get overly annoyed.

When we lived in Adelphi, MD (typical sloburbia, with houses spaced
very close together on small lots with *some* woodlands) we had
frequent bird strikes on our bay windows, sliding glass windows and
occasionally the back porch door.

Now we live on a fairly large lot (>4 acres) in rural Western Maryland
and I can honestly say that we have had no collisions with our glass
windows.  We *turn off* our lights or draw shades/curtains at night,
starting right at dusk.  The only collision in over 5 years was a
Coopers Hawk hitting our SCREEN on the back porch, causing no injury
to the Coopie but causing me to spill a large cuppa coffee all over
myself, as I was standing right next to the screen when he hit it
while chasing a goldfinch.  I now believe that if a bird has enough
"space" to recognize it's flight path, at least with low buildings
like residential structures, it will discern a fake reflection of
greenery from the real thing.  As Gail astutely noted, also, birds see
into the UV spectrum, and some species can even see towards the other
(infrared) end of the light spectrum.  Reflections in glass are not
"mirror images" of the green spaces they surround, as the UV
refractions alter the image, in a bird's eye view.  And, BTW, we have
approximately 25 bird feeders and six bird baths scattered about our
property.

Ignore all of this for those crazy Northern Cardinals during breeding
season.  They are just plain nuts.

Conclusion: for the most part, any efforts to find solutions for this
problem should start in urban areas.


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Frank Boyle
Rohrersville, MD

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