Roslyn

Recently 2 crows have come to my outside deck to eat the seeds I have placed there for birds. I assume they are the same two. Sometimes they arrive when most of the seeds are gone. One now comes to my glass door and starts banging on it, occasionally jumping up and down as s(he) bangs. It is a very loud bang as if a hammer...quite scary the first time it occurred. The second one seems to be watching, on guard. I have never opened that door to put seeds out but I have sat near the door or passed behind it. I now understand that their bills are not sharp so I may not worry any more that they will crack the door glass!