Unclear whether this was a Allen's or a Rufous Hummingbird, but it is unusual to see either of these at this time of year.
At least three individuals.
A Black-and-White Warbler was working the same willows and cottonwoods where I saw a Black-and-White Warbler last spring. These trees are just upstream of the pedestrian bridge linking the San Lorenzo Park and River Street.
This rarity has been seen consistently at the same spot for weeks.