This morning I put in minimal effort to locate some Black Rails at Martinez Regional Shoreline, and was rewarded with at least 3 different individuals between 10:50 and 11:10 AM. Two were heard in the central part of the marsh (roughly where the obliging Least Bittern was a few years ago) and one was at the west end. They were both singing and "growling", and of course I did not see them.
Black Rails are state-listed as Threatened. Please do not use playback on these birds.