The first bid, a small Gull, I noticed at the water's edge near the White Rock Pier. It was all by itself.
I'm assuming that it's a Bonaparte's Gull?
While talking with some other birders I encountered at Campbell Valley Park, I caught a flash of yellow in the sky and saw this bird alight at the top of a nearby tree. It was about 30 meters above ground and against the bright sky, difficult to see. I snapped a couple of photos of the area I guessed it was. It appeared to be all yellow, but had wing bars.
My guess is that it's a Yellow Warbler female?