The tern (I saw 1 of the 2 that have been reported) was flying above
the gravel dump at the far northern end of the park.
The laughing gull, in fresh breeding plumage, was seen from the
complete opposite end of the park, down near the railroad bridge at
the Anacostia Marina (the one with the big blue building with white
doors).  I watched it in the water and then perching on a pile-on, but
could not relocate it when I got closer.
The Osprey was flying upriver.  I saw it near the soccer fields.

Other birds included: Red-Shouldered Hawk at the Park Headquarters,
GBB Gulls (my LBB drought continues), and several Double-Crested
Cormorants (no NeoTropicals as far as I could tell).

Nick
birdDC.blogspot.com