[mou] Strange robin behavior

[Jenn]

My mom just emailed me with this description of some
weird robin behavior. We were wondering if anyone has
any ideas why she is doing this?

"I heard a persistant pounding noise.  It sounded like
someone hitting on a board just outside my bedroome
window.  there was a robin trying to fly into the
window!  It flew up about 6 to 12 inches and then out
and back to the sill.  My moving the curtains did not
scare it.  I had to put my hand right up to its face
to scare it away!  I figured all that thumping wasn't
good for it.  I made coffee and there was the noise
again, but not in my bedroom, but in the guest room
window, doing the same thing.  I had to wave at it
again as just opening shades and curtains did not
startle it.  It was the same robin - one of its tail
feathers was turned up or out a bit and was white.
It's mate was close by in the tree but didn't do that.
It kept coming back to those windows at least a dozen
times, even when I was at the computer!!  What do you
think it was doing?"

We're both curious and I thought I'd see if anyone has
any ideas...

Jenn