Why is this robin repeatedly flying into my window?

For the last few days, a robin has appeared outside my window and made repeated attempts to fly into it. He starts from a branch maybe a foot away, so he never builds up much speed and is apparently uninjured. But he (or maybe she) is doing it over and over again. He’ll bang against the window for several seconds, then take a break on that branch for a minute, and then try again. And the cycle repeats. Several times a day, several days now.

I’ve seen birds in the past apparently mistake a window for an opening they could fly through, and then fly into it at fatally high speed from a distance. But this seems different.

Any idea why a bird would do this?

Is it reflective? I’ve heard that birds will attack their reflection thinking it is an intruder in their territory.

Yes. He sees his reflection in the window and thinks it’s another male. He’s trying to chase it away and no doubt is quite puzzled that the other male is such a badass and refuses to be chased.

You’ll dissuade him if you can eliminate the reflectivity of the window, perhaps by soaping it temporarily. He’ll stop once his testosterone levels drop later in the breeding season, but that might take a while.

Mockingbirds and other birds sometimes glimpse their reflections in rear-view mirrors of parked cars and spend days battling the “other bird.”

Male birds would attack my car side mirrors indefatigably in the spring until I moved to a place with a garage. Same thing.

Last year I had a brownheaded cowbird doing a similar thing. I had a thread here about it and learned that birds can see reflections where we can’t and he was doing the aggressive territory thing. He kept at it for a long time.
Well, Kevin is back. (We named him Kevin, and we like to think it’s the same bird this season, though who knows.)
My son got tired of Kevin’s pecking at the window and put a Post-It note in the window that says “Kevin, go away!”
It seems to be working.

Over the last week, we have had three birds come down our wood-burning stove chimney, to end up flapping and fluttering and making a commotion. We have to come down, open the window, then open the stove and wait for the bird to leave.

It’s worse when they do it at night: they tend to fly towards the light, but at night it’s difficult to make the window any lighter than anything else they can see when they emerge from the stove, so they end up flying around the room haphazardly. (I finally figured out we could open the door to the attached garage, and the garage has bright fluorescents; it worked)

Are the birds pissed off at us or trying to warn us about something? Should we rent a copy of Hitchcock’s The Birds to add to our coronavirus quarantine viewing queue?

I’ve had many birds dive bomb the French doors, much to the cat’s delight.

There’s something about robins. When I lived in the Pacific Northwest, we had dozens of different species in our front yard but it was always dead robins we would find under our bay windows.

What you should do is get a bird guard screen mounted on top of your chimney. It’ll save you a lot of hassle, and probably save some birds’ lives. Here’s a sample (I know nothing about the particular company; it just came up on a google search. I recommend calling your local hardware store, if you’ve still got one.)

Been there, done that.

“Damn, that other bird has kicked my ass 200 times in a row! But now he’s starting to look kind of shaky. I can win this! Must… attack… again…!”

I had a female cardinal attacking my bedroom window because she could see her refection. Because there was a tree branch right next to the window to stand on when she got tired, she kept it up for hours at a time, for days. I finally got her to stop by taping white tissue paper to the entire inside of the window. It still let light in but she couldn’t see herself anymore. I took it down after a week and she didn’t start up again.

Occasionally a hoopoe bird will peck at the window adjacent to where I type at laptop. I think he/she is saying hello.

Two weeks ago our large window came under attack by two crows who repeatedly crashed into at high speed. (The crows normally stay in the orchard, but drought here is very severe: they came out of the orchard to access water in water lily bowls near our house.)