River of Birds

As the sun retreated beyond Mount Diablo, the Harriers took last looks over the marshes and the Goldeneyes gathered in mounting floating shoals. The waters of the Sacramento/San Joaquin delta were calm. The east-flowing breeze cooled to herald the darkness and overhead, a river of birds began to flow. Heading north of the setting sun, high in the sky, a seemingly endless stream of black birds snaked along in a pulsing, choreographed, ribbon of bounding wings. Even with binoculars it was impossible to find the beginning or the end of the flock which held itself in a compact sinuous band. The cord of birds was many miles long and it coursed by silently for over 10 minutes before dissolving as discretely as it appeared. I've never seen anything like it.