Pigeon Pall

I'm worried about the pigeons that gather to eat the bird seed I lay out. Over the last month I've collected five bodies. Something or someone is killing them - probably a hawk - but I haven't seen or heard the hawk; just the scavenging crows. Silent death from the skies above. 

Disease?  Poisoning? Something is happening....

Still, the birds entertain. There was a crow I hadn't seen before that was frantically trying to get my attention as it got dive-bombed repeatedly by an ill-tempered Northern Mockingbird. I could almost understand the crow as it cawed. "Hey! Remember me? I'm your favorite crow. *OW!* Do you have any of that prime bird seed? *OW!* Stupid lunatic bird! Any - anything for me?"