Myrtle, we too have been seeing this "strange" behavior of the Mrs. Cardinal (not him)... we've fed and traveled far and wide to bird for 60+ years and have NEVER had her pecking away at the car mirrors beyond breeding season. It's the dead of winter (though we've had very little of it in actuality), cold at night, occasionally snowy, and def. NOT breeding season, yet if we don't turn the mirrors in on one car and bag the other she spends her day fighting them.... wish I had another solution for you. If it were me, I'd tape some pieces of cardboard on the outside of my windows, but then I'm a bit crazy anyway :-))))). I keep mylar and fabric streamers hanging outside all my windows... they flutter in the wind and along with a few silhouettes taped on the inside keep the window strikes to a minimum.

There are lots of suggestions on the web for trying to deter birds from window strikes but biology may trump human attempts to stop them under some conditions.

While searching for info on this I ran across something related to higher than normal light conditions during non-mating seasons that contribute to higher than normal testosterone levels which are largely responsible for territorial protective behavior. It's called "gonadal recrudescence" and in the simplest terms they get a second annual flush of the hormone that makes them behave in such a territorial fashion.

Maybe it's the weather pattern this year. Some scientists are even studying birds that nest on light poles and find they're nesting all year round and feeding young at night because they're reacting like chickens who get light 24/7 to increase egg production.

Some anecdotal evidence says some birds keep this up all year round for a few years in spite of attempts to reduce window reflections, move feeders and other human interventions.

We can try all the standard things like soaping the window, streamers, raptor decals and such. After you've done all you can do guess it's up to mother nature.

Put stuff on the outside of the window, to break up the reflection. Stuff on the inside, and closing curtains, only increases the reflection.

I have tried decals outside the windows. I think the problem is the window is about 5 ft high. When I put a decal on it that does not cover all 10 square feet the birds just find a spot where they see there reflection and figure the invader is hiding in that corner. I have not tried soap. Not crazy about soaping my own windows but maybe it will be the lessor of the evils.

Some people suggested putting things like Bon Ami paste on the outside and all sorts of things!

10 square feet is an awfully big space to actually cover with anything particularly if they'd just find another window to bash themselves against. Streamers or carboarding the whole window for a short time might break them of the habit if you can stand it.

National Enquirer Headline: "Woman trapped inside own home with darkened windows...held captive by hormonally imbalanced birds!"

I know it's not funny if birds get hurt but there's only so much you can do once you cover your whole window for a time.

Luckily our cardinals stuck to the car mirrors for their challenges and stopped after mating season. Have no idea where their nest was but they fledged one male. Guess I'd be turning in the mirrors too if they hadn't stopped.

A couple of robins took to knocking at a living room window that already had the cross wood for 12 panel windows. It was around the corner of the house from their nest in a big old pyracantha bush. Stuck some post-its in all 12 window frames but I think they stopped on their own after little ones fledged.

Good luck!

Oddly, it's the same two for a year. Maybe they have brain damage from so many head shots. I think they sit so close they don't have any speed when they hit the window. THey sort of lunge at it more than flying in to it.

Off topic... I'm curious. Is the window 10 square feet (roughly 5 feet by 2 feet which is not very large at aoo) or is it 10 feet square (10 feet by 10 feet)?

It's lucky the two cardinals that insist on attacking the window aren't hitting it very hard. Maybe all the other birds will just be content to sit by and watch their lunacy :-)

I think the problem is a lot different in your situation where the birds seem to think they are attacking their shadow selves in the window. Seems to make sense that none of the decals or anything will stop them, because putting decals up just makes birds aware that there is something more then empty space in the window opening so they can avoid flying into the glass thinking that they are just going from one place to another. The decals might make the window glass show up but they're not going to prevent the birds from seeing their own reflections. And as long as the reflections are there, they seem to want to fight and drive them off. I bet if you could find some sort of anti glare surface covering for the glass that would do the trick. They make it for eye glasses, but I've never heard of a treatment like that being used for any other purpose. I wonder if it's even available.

10 sq ft, apx 5or 6 by 2 glass area. We have 2 of these windows on that side of the room. They attack them both. You are right, I need to stop the reflection. I have used things I bought intended for that but they are just pieces of what I would call contact paper, hard to get on the outside and kind of ugly and did not cover enough of the window. I must think about something similar but bigger and easier.

I had a problem with goldfinches this past year hitting one particular large bay window. I replicated a solution I saw on Ebay. Vertical pieces of fishing line about 1 foot apart (on exterior of the window), secured top and bottom with a nail. Along the fishing line, I tied one bird feather every 6 inches, and hot glued it to the line, to be sure it would stay. When in place, the feathers move in the wind. The theory is that birds are afraid of single feathers strewn about, its supposed to remind them of danger... and it does break up reflections. I have had less strikes, but I put it up at the end of the goldfinch migration. You can look it up on Ebay under Feather Guard.

Thanks, I found it. I think I will try it.

We had the same problem with male and female cardinal, pecking very very hard at 6 of our windows, all day long. On these windows you can see the reflection of the sky and trees since we have a park after our backyard ends. Anyway we were almost to spend $500 to put sun screeners to these windows but somebody suggested to try the shiny windmills from wal-mart (99 cents each). The ones kids play with. So far these birds don't wake me and my baby up in the morning anymore:) So, they stay away! I hope this is gonna last. We put them up just a couple of days ago, and they were way cheaper than the sun screeners...:) Good luck!

I tried to do a search for shiny windmills on Wal-Mart website but no luck. Do you have more details/product information. I have 4 windows that I was looking to put sun screens but reading your post from April 09, 2008--I would rather go that avenue.

Thanks!
Bela