Say's Phoebe is primarily a migrant and winter visitor to our area, although it may breed occasionally in eastern sections of the San Francisco Bay Area. This image shows the orange vent and lower belly typical of the species. Overall coloration averages paler in Mexican populations which also have a larger bill. Digiscoped with Panasonic DMC-LX5 | Nikon FieldScope III | 30XWA | hand-held (no adapter).
References:
Farnsworth, A. & Lebbin, D. (2018). Say's Phoebe (Sayornis saya). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/57382 on 6 December 2018).
Schukman, J. M. and B. O. Wolf (1998). Say's Phoebe (Sayornis saya), version 2.0. In The Birds of North America (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.374