According to CalFlora observations, this species is known from other beaches in Marin but no known records from Muir Beach.
Visiting a flower of yellow sand verbena (Abronia latifolia).
Spotted a few Western Willets in Corte Madera east of 101 on 7/26/2015 at 10:45am. Flight revealed beautiful black & white tail span.
Group of nesting American White Pelicans just east of 101 in Corte Madera on 7/26/2015
early migrants or maybe second year birds which did not mate and return early.