Was at Patuxant visitor's center today (Sunday) from 11-12. There were no gulls on the lake at all, just a very few flying over. One lone ruddy duck. On frozen Cash Lake were some rusty blackbirds and several common snipe, and an immature bald eagle being chased by crows. A red-tailed hawk was hanging around the parking lot playing tag with another batch of crows. One of the snipe landed next to another, displayed by spreading its tail, and seemed to try to mount the first, but then the other also displayed, and chasing went in both directions. Anyone know what this display is for?