Murmurations

Above, a large flock of Dunlins flies swiftly over the water.

Their synchronized movements involve sudden changes of direction in which the birds flow and pour through the air as if they were one organism. Maybe they do this to make it harder for predators like falcons to catch them:

But they lift off to perform their mass acrobatics even when no predator seems to be around. This is part of a flock—numbering ten thousand or more birds—who stayed aloft for over an hour, undulating like a ribbon across the sky:

Dunlins are colorful birds during the breeding season, but in winter they wear a drab, basic camouflage:

Their long bills are used to probe in the mud for invertebrate prey:

This group of Dunlins came to the margins of a salt marsh to feed as the tide receded:

A Merlin (a kind of small falcon) dashed in from behind me and tried to grab one of the Dunlins. She wasn’t successful, but she circled back to land in a distant tree.

I captured this image as she passed by. The out-of-focus birds in the background are some of the Dunlins she flushed:

She tried again over an hour later, catching the Dunlins off guard.

They suddenly sprang into the air, but it was too late. The Merlin streaked through the flock like a meteor and came out the other side with one of them in her talons.

A Glaucous-winged Gull frantically pursued the little falcon, trying to snatch her prize:

The gull almost succeeded, coming very close to grabbing the hapless Dunlin for itself. But the Merlin managed to out-fly the gull, even though she was carrying another bird.

The gull gave up long before the falcon reached a far-off treeline.