A Peregrine was perched on the super-structure of the RR bridge, east side at about 1pm today.

Hundreds of Scaup, both Greater & Lesser, were in the river in several groupings.  In mid-river, just beyond a large raft of Greater Scaup, was a lone Ruddy Duck.
Nearly 100 Mallard were around.

About a dozen Greater Black-backed Gulls were in the channel.

Also in the Channel:
Double-crested Cormorant (4)
Lesser Black-backed Gull (2)
Canada Goose (ca. 300)

Good birding,

--
Frank Powers
Glen Echo, MD
Montgomery County