This a.m. prior to going to work, I spent a few hours at Otter Slough CA (no surprise there, eh?).
I only birded Consrevation Lane loop, HQ area, and a small portion of the boardwalk trail. It was at the East campground (located just South of the southern entrance to Conservation Ln.) where the imm. Peregrine Falcon was perched in an oak watching over the recently harvested rice field on the East side of the road where dabblers were busily foraging. The Falcon afforded me relatively close range looks as I stayed in my truck and observed it.
Behind the HQ building, an indistinct buzzing caught my attention. Not sure if I was hearing a Ruby-throated Hummingbird, I investigated closer. While standing near the edge of the wooded area, a nice fairly tight flock of migrants went through the area.
Species in this flock included (but not limited to):
Blue-headed Vireo (3)
Orange-crowned Warbler (2+)
Tennessee Warbler (1)
Yellow-rumped Warblers (20+)
Nashville Warbler (1)
BLUE-GRAY GNATCHATCHER (1)
Black-throated Green Warbler (6+)
Winter Wren (2) Also the source of the buzzing that drew me to the area.
and then some regular residents mixed in also - Titmouses, Chickadees, WB Nuthatches, etc.