The best care you can give a baby bird is to leave it be, where its parents can care for it....they are most likely keeping an eye on it! If it seems to be in danger from a pet or exposure, you might create a make-shift nest out of a towel and place it in the shade of a nearby shrub, or in the crook of a nearby tree.
Please do NOT take the animal home or bring it to the refuge. The refuge is not equipped to care for injured or orphaned animals. In Butte, Glenn, and Colusa Counties the Valley Oak Veterinary Center on Dr MLK Parkway in Chico accepts wildlife. In the Sacramento metropolitan area contact the Wildlife Care Association at 916-965-WILD(9453).
See a list of rehabilitators in CA