Ask Ms. Nature Person: Why Is a Cardinal Tapping on My Window?

Ask Ms. Nature Person: Why Is a Cardinal Tapping on My Window?

We’re not sure if it was the [ expletive ] headline or the angry birds, but there was a remarkable following to last week’s article headlined, Why Are Those [ Expletive ] Birds Chirping at 3 in the Morning?

So much so, in fact, that Pam Otto, the nonpareil manager of nature programs and interpretive services at the Hickory Knolls Discovery Center, a facility of the St. Charles Park District, would be entirely justified by using a few expletives this week to describe Kane County Connects editor Rick Nagel.

That didn’t stop us, however, from forwarding this followup question from alert reader Barb Granatelli:

Q: I have been having a male cardinal bird pecking at my bedroom window and my patio door anywhere from 4:30 a.m. and on into the morning. I am assuming it might be reacting to a reflection in the window. I have been living here (DelWebb in Elgin) for over 10 years and have never had this happen before.

What’s going on?

Here’s the answer from Pam, who was in fact kind enough to respond. She can be reached, by the way, at 630-513-4346 or

A: Rick Nagel of Kane County Connects forwarded your email about the overzealous cardinal pecking at your window and door.

You are exactly right, he (Editor’s note: The pronoun is referring to the cardinal, not Rick Nagel) is reacting to his reflection in your windows. As for why, it all comes down to hormones.

This is the first of two breeding seasons this species experiences in our area. During this time, male cardinals will react to pretty much anything red. (I used to drive a red truck and got dive-bombed regularly at this time of year.) A reflection in a window is a clear target; plus, it moves!

The male is defending his breeding territory to the best of his ability. If you’d like to deter this behavior, what you need to do is block the reflection.

One effective method, though not terribly aesthetically pleasing, is to soap the window on the outside. Taping up paper, also on the outside, will work, too. The good news is, the behavior shouldn’t last too very long. Once the chicks are reared, he will calm down again.

As for why you’ve not witnessed this behavior before, I’m not exactly sure. Perhaps a tree or shrub was removed that would then cause the light to hit the window in a way that would increase the likelihood of reflection? Or maybe you had your windows washed recently? I guess the answer to that question is … anybody’s guess …

Thanks for asking, Barbara! If you have any further questions, don’t hesitate to let me know. Thanks!

If you have any further questions of a natural variety, please email, and I’ll see if Pam is kind enough to answer.