Come spring, the bluebird pair that nests near my barn starts attacking all
the car windows. They don't actually hit the windows, they flutter up and
down very close to the glass surface. If a new vehicle (with bigger, better
windows) parks in the barnyard, they will usually challenge those windows.
This behavior continues throughout the nesting season. I've even seen the
older fledglings attacking "the car window birds".

Last year, these bluebirds nested successfully  and fledged 3 broods/5
babies each (one of my most successful pairs). 

I was alarmed by this behavior last year, but now I don't worry about it.

Covering ALL the porch window surfaces with either screens or special bird
films might work. Here are two links:

http://www.flap.org/new/film.htm

http://www.birdscreen.com/

Good luck,

Felicia Lovelett
Sykesville, MD

-----Original Message-----
From: Maryland Birds & Birding [mailto:[log in to unmask]] On
Behalf Of 
Sent: Thursday, April 05, 2007 7:00 PM
To: 
Subject: [MDOSPREY] Bluebird behavioral challenge for homeowner

Here's something for you bird behaviorists to mull over.
My down the hill neighbor has of late been won over by our missionary zeal
for feeding -- and creating yards compatible for nesting -- birds.  They
have been filling a tubular feeder with appropriate seed and had recently
put up a Bluebird box.  
All of us were pleased to see that a pair of Bluebirds had been attracted to
their yard, and to their box this week.  However, their appearance has been
accompanied by a challenge, as of yet unmet and unsolved.
My neighbors have a virtual wall of glass overlooking their backyard from
their living and dining room areas.  This pair of bluebirds are continuously
attacking their reflections in the glass (mostly male, with occasional
female backup) during the morning and evening hours.  They consulted with
the staff at the Backyard Naturalist, in Olney, MD, who suggested they hang
a tarp over the glassed area they were attacking.  
They did that.  The Bluebirds simply moved to the uncovered glass area and
continued their aggressive behavior.
Aside from being concerned about how much time and energy the birds were
spending attacking their reflections, my neighbors are concerned that the
pair is speckling their glass with feather down and spittle and leaving
fecal material all over their deck.  The deck, incidentally, was recently
rebuilt and is the pride of the husband.....
My questions are these:  Are there any recommendations as to what additional
measures might resolve this situation, and am I correct in telling them that
the behavior will be self-limiting as the pair is distracted by nest
building and rearing of their brood?  Or, will they likely not select my
neighbor's  birdbox because they were discouraged by their "competitors"?
Answers and suggestions would be appreciated, off line if you prefer.
Thanks.
Jay and Diane Jones