question about bird flight patterns
 

For any ornithologists/bird enthusiasts here: I'm curious to know if there is a behavioral explanation for starlings and pigeons flying in patterns as a group. Sometimes they do it in huge numbers, sometimes a couple break off from the larger group and fly in smaller groups alongside the others, and when I see it happen, it last a couple of seconds at a time. When viewed in large enough numbers from a distance, they look like fabric blowing in the wind and I think it's fun to watch them. But why do they do it?

I'm not an ornithologist, but the explanation I've always heard is that it's a survival mechanism. A single starling is easy pickings for predators, but by forming these huge groups they create a situation where a predator is overwhelmed by the sheer numbers and has a hard time picking out one individual. So safety in numbers and all that.

It also has to do with aerodynamics. When the guys at the front get tired, they break off and trade places with others.

I'd also think that some might break off from the main group to look around for food, or to find more favorable winds, or even just get bored (birds are highly evolved enough to get bored, right?)

Here's why:

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Good stuff. Thanks, all.

Schools of fish do this as well, for the same reason.

And RB, awesome video find.

I agree, awesome video! In case it wasn't obvious, a peregrine falcon was attacking the group. Here's another video showing how lethal the peregrine flacon can be against a lone bird:

so thats what happened when my pigeons came back less one...

great vids

Birds are fab, aren't they?! In PDX each year there is a huge group of Swifts that live in one of our school's chimneys in the Fall. They leave as a group at the same time each evening and return later at the same time in that same grouping. It is nature at her most finest.

that flock looks like a fast moving single cell creature in that vid.
a hugh aerial amoeba.

Yeah. I've only seen it in person once in my life, but it's AMAZING.

We have a LOT of starlings around these parts for some reason, so I've seen that sort of thing a few times. I dislike them; they're obnoxious, loud, scare away other birds, and love to nest in the eaves of houses. I once even had some peck out the screening covering the vents around the eaves and build a nest inside of the wall of my house. THEN they had babies. I didn't feel the least bit bad when Dad hammered a piece of board over the vent they had pecked through.

But it is pretty.

Yes, they are persistent little buggers. We had a hell of a time getting them out of our attic space, and they kept coming back and trying to get through the screen coverings afterward as well. They and non-native house sparrows are most numerous in my neighborhood—and the greediest at my neighbor's feeders—and I'm glad we have a healthy population of red-tailed hawks in the vicinity to keep them in check.

Love the videos!