If a bird calls in the forest...

...and nobody is around to hear it, does it make a noise?

Well, yeah, but it's more complicated to prove than you might think.

Researchers are developing ways to record and identify bird calls so as to track bird populations in certain areas. In the past, a bird census was done by people who actually went out into the wilderness to count the birds in an area. Sometimes, it's difficult to rally a bunch of ornithologists to troop into the woods to count birds for hours, so they're attempting to count birds by recording their calls. At first, you think it'd be relatively simple: just stick a recorder in a tree for a while and then count all the bird calls. The problem, however, is that the tapes do not distinguish between calls and without a sight on the bird, it's not always clear to tell who made the call without in-depth analysis of the recorded sounds.

So, leave it to science to come up with an ingenious(ly complicated) way to count birds without actually being there. They've developed devices that can distinguish the calls of certain birds from the background symphony of flora and fauna. It's way too complicated for me to understand, so I'm not even going to try to explain it, but the result is that they can track bird populations more easily and much more efficiently. Right now each device can only distinguish one kind of call, but they hope to make a machine that can distinguish a bunch of different calls so they can count a lot of birds at once. As a neat side effect, this method is less obtrusive, so they might be able to record birds that could otherwise be spooked by a person walking around counting them.

Read about all of this scientific fantasticness over at Science Daily.