I ran across an interesting phenomenon today, courtesy of Youtube. It's well known that if you keep a parrot in your home, it will learn all sorts of people noises like swear words, the sound of a crying baby, and the Spongebob Squarepants theme song. But you may not realize that wild birds learn people noises, too.

 

Certain bird species have the amazing ability to mimic the sounds of their environment. Parrots are the most well-known of these, but the mockingbird is also a star in this regard. 

 

Last summer I was out working in the yard when I heard the sound of a "crosswalk signal for the blind" signaling that the light was green. They make a distinctive "boo beep boo beep" noise, in order to let people with reduced vision know when it is safe to cross the street. The surprising thing about this is that I live in the middle of the woods. However, the next town over (about 15 miles away) employs these crosswalk signals downtown. 

I'm still not entirely sure which bird made the noise, but it mimicked them perfectly. Many wild birds have the interest and ability to mimic noises, including all of the corvids (jays, crows, and ravens). Ravens are somewhat common in my area, so my assumption is that it was a raven who was visiting from town.

 

There is no consensus on why birds mimic other noises. In the case of flocking birds like parrots, many people feel that the mimicry helps to keep the flock together in their thickly forested terrain. The noises serve as a sort of cultural bond that may help cement mating pairs, sort of like the bird equivalent of a human couple's in-jokes.

 

In other birds, such as mockingbirds, the birds seem to be driven to add more and more noises to their library of sounds. This may be a mating behavior, with the males who can recite the most noises being the ones who are most likely to impress a mate.

 

It's understandable that we are most fascinated by pet birds who learn human speech. (Creaky and unsettling as the bird's specific rendition may be.) But it seems equal parts fascinating and depressing that wild birds are learning noises like car alarms, ambulance sirens, and the trill of a cell phone's ring tone. This mockingbird even finishes its car alarm rendition with the double chirp of the alarm being remotely deactivated!