On birds

Posted on July 7, 2010

23


A distracting Robin

When I stepped out into the backyard today, I found a robin in full bizarro mode. It was hopping and flying in short arcs while making a sound like a puppy being repeatedly kicked. But a cartoon puppy, not a real-life puppy.

Meanwhile, a young robin, sort of the equivalent of a pre-teen, was sitting on the patio looking stunned. (Like I said, pre-teen.) At first I thought it was seriously injured, but then it hopped/flew for a few feet, so I backed off. I’ve been going outside every half hour or so to check on the situation. The baby has been moving around from yard to yard, but I can always tell where it is by the crazy antics of the mother.

A sidekick Robin

That’s a weird survival trait, when you think about it. Why doesn’t the mother just sit still and keep quiet? Her antics are designed to draw attention to her. When danger is proximate (such as me stepping out the door onto the patio), this makes sense. She effectively draws attention away from her baby . But I’ve been watching from the window, and she never stops. No matter where the baby goes, the mother is essentially telling the entire world where it is. Why doesn’t she just shut up?

But then the whole “peeping” thing with birds has always puzzled me.

As anyone knows who has ever tried finding a bird in a tree, when they sit still, birds are pretty damned hard to find. You could pass by a tree with 50 birds in it and never know. Or at least, you wouldn’t know if they weren’t continuously yelling  “Here I am! Here I am!” at the top of their little birdie voices.

That’s just dumb, right?

They peep when they’re sitting still, they peep when they’re hopping, and they peep when they’re flying. They start peeping before the sun rises, and continue peeping after it’s set.

That takes a lot of energy. Imagine yelling “Here I am” every few seconds, all day long. Energy requires calories, and calories require a constant food source. Since flying is already an energetic activity, what advantage can birds find in this peeping that makes it worth the cost in extra caloric demand?

I think I figured it out.

A children's story Robin

While it’s true that birds can blend into trees quite easily, any movements they make will create a rustling noise that can pinpoint their location to a predator. Trying to remain perfectly still, however, is difficult if you want to eat, so instead of augmenting their camouflage with silence, birds augment it with a Phil Spector-like Wall of Sound — a cacophony of peeps, cheeps, and squeaks that make tracking one bird by sound alone extremely difficult.

Best of all, since they have to keep up a constant chatter, they can use it communicate between themselves. One set of peeps can mean “Uh-oh, cat coming!” while another set can mean “Come eat! New garden planted here!”

Peeping is a lot of energy, but worth it in terms of survival.

And  for more than mere physical survival. There is a need in every creature to make its presence known to others of its kind. To say, in effect, “Here I am!”

Surely Twitter proves that, doesn’t it?

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