Working the trunk and limbs of several cottonwoods. Two other trunk creepers were present in these same trees and from time to time one would chase the other. There was a Red-breasted Nuthatch and a Brown Creeper.

This bird was going after insects the way a flycatcher should in the mid to upper conopy of cottonwoods on east bank of San Lorenzo River. I don't think I would have been confident identifying this bird if I had been alone, but I was with members of the Santa Cruz Bird Club, including Steve Gerow, who are reliable at identifying species like this.

The following birds were also seen nearby:
Black-and-White Warbler
Eastern Phoebe
Red-Breasted Nuthatch
Glaucous-winged Gull