The first is a shorebird which is experiencing population decline throughout much of its arctic breeding range. It migrates from the far north through the Mississippi valley but occasionally wanders eastward. The islands in the Susquehanna river sometimes attract a vagrant or two, and that's where one was found last summer. The bird is a Buff-breasted sandpiper, and the pic doesn't really do justice to the delicate orange, brown, and black colors the bird displays in good light:
The next rarity is a small western songbird called a Townsend's warbler that sometimes strays east after the breeding season is over. This one was found in Cobbs Creek park in Philadelphia last fall.
The last find is very rare. It's a European bird related to the American robin called a Wheatear. This one was found by a guy bicycling in Fox Point park in northeastern Wilmington, right along the Delaware river in mid-December.