The Lesser Goldfinches seem to be leaving Delta Ponds. I have been seeing them in the trees alongside one of the ponds there. That's where I got this picture of a gorgeous goldfinch

"Lesser Goldfinches are small finches with bright yellow undersides. Males have greenish-brown backs, black caps and wings with two white wing-bars, and a white patch on each wing. Their tails are black with white patches on either side, and their undertail coverts are yellow (contrasting with the white undertail coverts of American Goldfinches). Females lack the black cap and wing-bars of the males, are not as brightly colored, and lack the white on the tail; they do have white patches on each wing." - http://birdweb.org/birdweb/bird/lesser_goldfinch