This afternoon from 12:50 through 2:15, from Border Field State Park I observed at least 7 brown boobies ranging from just south of the border to NW of the rivermouth, and foraging at various distances from just beyond the surf out to the horizon. They ranged back & forth, close & far, but most of that time at least 2 were visible together, with a maximum at one time of 7. Just after 1 pm, a white-bodied Sulid joined two of them briefly but I lost view of it after it landed on the surface of the water to the NW of the horse trail but SW of the rivermouth. It was too distant to clearly discern tail or face/bill details, but with black outer wings & trailing edge of inner wings, white body including head and back and most of inner wings. Larger, longer necked, pointier winged, different color pattern, & more labored flight pattern than adjacent gulls (& much larger & very different flight pattern from adjacent royal terns). A few shearwaters could barely be discerned out on the horizon; likewise with a feeding frenzy around a fishing boat that seemed to be drawing the attention of the boobies when I left.
At least 1 large-billed sparrow was foraging among kelp wrack at the rivermouth.
An adult least tern with 2 fledglings (none banded) landed briefly S of the horse trail & were foraging in the surf.
Earlier, 2 Baird's sandpipers & 1 semipalmated sandpiper were seen briefly within interior ponds in closed portions of the South SD Bay saltworks, but were not re-found later. Depending on their movements, they may be scope-able from the bikepath off 13th, 8th, or 7th St at some point.
San Diego, CA