This was a critical time for the Native Americans inhabiting coastal California regions.  There are not many findings, artifacts, and such during this period.  It leads to beliefs of possible population declines during this time.  But, the migratory nature of the people was coming to a major change.  The oaks were flourishing.  Food sources were changing.  And, collecting methods were improving.  

During warmer months, it is believed the Native American would follow life (deer and such) up the mountains- Santa Monica Mountains and Frazier Park areas.  This was done for religious reasons- higher on the mountain, closer to the heavens-and they were following food sources.  As the weather chilled they returned to the ocean and lowlands. This migration brought about important changes in the Native American society.  They noted plant growth and learned propagating.  They carried things to improve their lives in their travels.  And, they improved their ways of carrying these things.