After speaking with an Audubon Society member in Oceanside, CA a recommendation was Guajome Lake which is off the 76 highway in north San Diego County. The brief visit turned-up two Least Terns in flight. Easily identifiable with the whitish forehead, primaries and tail were same length and the bill more of a solid yellow in comparison to the bill of a Forster’s Tern (1 reasonably good photo below). Upon scouting around the lake, a Black-crowned Night Heron flew in with its prey, a meaty catfish which initially seemed too large for the hunter himself. There’s a photo below taken from about 30 yards away.
Least Tern in flight
Black-crowned Night Heron with a meaty catfish