So, after talking to some of the other counters at Mt. Peter Hawk Watch and getting some feedback from John Haas, the consensus was that the two Lesser Yellowlegs in the previous post were just two young birds playing in such a way that it will prepare them for adulthood.
Today, out at Wallkill River National Wildlife Refuge, I came across two more young birds interacting – first a curious young Northern Harrier that flew in close to me. He was joined shortly after by a young Cooper’s Hawk and the two tangled for a bit. More playing/training?