Birdhaviour

This is from the DC-DOT traffic camera looking out onto the Southwest Freeway at 7th St. I was particularly fascinated by (and watched for a couple of hours, until they decided to leave) this large group of birds - can't quite tell what they are from this vantage. They just swarmed around a mass of stuff that was sitting there. I have to guess someone dumped food garbage there or something. I mean, that's a lot of birds. In this image, they appear to be taking up the equivalent amount of space as that white van to the left, in terms of depth, and the equivalent of a couple of lanes of traffic in width. Weird.

Additional pics: 2 | 3 | 4 | 5 | 6 | 7 | 8