Interesting birds but no warblers

A bit of a late start might have resulted in the lack of warblers yesterday. Continued movement was clear with several Phoebe. While tracking an aircraft heading out of National we spotted one and then two very high raptors heading east and eventually narrowed I'D down to Broad-winged Hawk, a new site bird. A few minutes later while watching a low military Helicopter flying down and then up river while we we standing in the river bed, a large crow distracted us with some impressive tumbling. Unfortunately it flew off downstream before too long buy we got a good enough look to see that it was a Raven. Interestingly Chrystal thought she had heard a Raven on a recent previous visit. Another good bird was a Lincoln's Sparrow which briefly showed along the rail track near the rusty bridge.