Tilden Regional Park, Contra Costa, California, US
May 5, 2017 5:30 AM - 7:45 AM

Golden Gate Audubon Society First Friday Special Dawn Chorus Bird Walk (our 6th annual), May 5, 2017.
We met at the foot of Canon Drive, by Big Leaf Picnic Area in Tilden Regional Park, and walked around in the nearby Meadows Playfield and then walked up to Blue Gum Gate and back. 
Serenades by Pacific Wren at the play field and House Wren in the eucalyptus near Blue Gum Gate were the highlights of the early morning.
This is the weekend for International Dawn Chorus Sunday, but we always do it on the First Friday walk of May. We read Dawn Chorus poems (Emily Dickinson's #723, Sarah Dugsdale's Dawn Chorus, and Kathe Jordan read her own).

Male birds are singing to say: I've survived the night, I'm on my territory, I'm well fed and full of stamina, what about you, I'm talk'n to you! Females are paying attention to length of song, consistency and accuracy of performance, presence in a previously-known location (birds do know one from another). Female social partners have been known to use the dark of early day to seek an "intimate encounter" with another male as a (brief) biological partner before returning to the nest territory. Birds with larger pupils sing earliest. It may still be too dark to see their insect prey, and that prey may still be relatively immobile from the night's cold, so the birds sing.