Today at work, I came across 6 Tree Swallows zooming around a large open field on the Gunpowder Neck portion of the Edgewood Area of Aberdeen Proving Ground (Harford County).

I also had about 100 Tundra Swan on a sandy spit jutting out into the Gunpowder river (Harford County).  Other birds nearby included 25 Green-einged Teal in a large cove on the neck. 

good birding,
Chris Starling
North East, MD