Marcophile: Warbler's window warpath

What do you do if a seasonal visitor shows up at your home, bangs on the window repeatedly and refuses to go away?

It's not a police matter; the visitor in question is a yellow-rumped warbler.

For hours at a time, the little birdie flies to the large window, its fluttering wings brushing against the glass. Or it sits on the sill, pecking and poking at the window.

We tried shooing it with wild arm movements. The "shoo shoo little birdie" effort failed and we felt silly doing it.

We then hung sheets of aluminum foil on the window, assuming that would change the image in the little bird's brains.

But the overwrought warbler just went to a different window and resumed its antics.

Did the bird want to come inside? Or did it want the bird it saw — its own reflection — to come out and play?

Experts agree that birds that fling themselves at our windows are seeing their reflections as a separate critter, possibly a rival or a mate. To quote Bird Notes from Sapsucker Woods, a publication of the Cornell Lab of Ornithology: "Passions run high in spring, when birds are hormonally primed for defending territories and mating. (When) flying at windows, car mirrors or hubcaps, these birds are fending off brazen intruders—-their own reflections.

"Because a reflection is a perfect match, returning blow for blow and tiring only when the bird tires, every encounter ends as a draw. Eventually, the bird turns its attention to mating."

So what to do when the aluminum foil fails and frantic human arm-waving is futile?

Again, we turn to Bird Notes: "To banish the phantom intruder, break up the reflection by rubbing a bar of soap on the window or covering it from the outside at times when the reflection is most problematic."

The bird's instinct to make baby birds overpowers its desire to destroy the identical bird it thinks lives in your bathroom or bedroom.

I also learned from the Cornell ornithologists some insights into the vocalizing of my favorite bird species, the mockingbird.

A bird lover asked the experts why a mockingbird in her yard imitates car alarms and subway train noises.

It turns out that mockingbirds continue to add to their mocking repertoires as they grow older, unlike most birds that learn a song and a chirp and stay with it for life.

"Some mockingbirds can learn up to 200 songs and often mimic sounds in their environment, including other birds, car alarms and creaky gates," according to Bird Notes.

As usual, it has a lot to do with sex.

"One theory is that a female prefers a male that sings more songs and a male can quickly add to his repertoire by imitating the sounds around him," it said.

In short, it shows him to be a quick study or a mature male with proven longevity and survival skills.

And the ladybirds think such a mockingbird male would be better at raising young and have access to "better resources."

Not many humans hang out under their paramours' bedroom windows anymore, serenading them with mandolins or mariachi bands.

Nowadays, car stereos and iPods perform those functions.

Also, it seems clear that learning to mimic a creaky gate would be a lot healthier than banging one's beak on a hurricane-rated glass window.