Field guides often have the Subject subheading/subcategory of “identification” which can be combined with a subject term you are interested in such as “ocean*”.
An excellent field guide series for California is published by the University of California Press and called the “California Natural History Guides” series.
Search by title for “California Natural History Guides” to view this series in the UCD Library Catalog:
Reach out with questions via email, or schedule a research consultation by clicking on the link to 'Book an Appointment'