San Francisco Bay is an amazingly rich ecosystem for birds of all kinds, but Sandhill Cranes are not a bird likely to be spotted there. Today we are going on an extended field trip to the Central Valley in search of the thousands of cranes that winter there. We will meet at the Cosumnes River Preserve’s Visitor Center located between Stockton and Sacramento to explore the preserve. Description and map can be found at www.cosumnes.org. Space is limited, so you must be registered to attend; call the Shoreline Center at 510-670-7270. Ages 12 and up. $20.