Tree Swallow Tirdoprone bicolor Reinsen, J.V. 1974 Jan.6 Ft. Reyes, Marin Co., Calif: 30 Olema Marsh Feb.8 Coyote Hills Reg. Park, Alameda Co., Calif: 2 birds perched in dead willow near woodpecker hole - investigating, nest sites already? Feb.9 Eastern Contra Costa Co., Calif: 1 Contra Loma Res. Feb.17 Kern NWR, Kern Co., Calif: 3000 - foraging everywhere over the marshes Feb.16 Elkhorn Grade Rd, Kern Co., Calif: 20 flying north low over salt bush at 1800- obvious migrants Feb.18 San Luis NWR, Merced Co., Calif: 200- Many courting, copulating, and investigating nest holes