Modifiers matching bivalve:

• fixed,
• intertidal,
• open,
• small,
• marine,
• sessile,
• cultured,
• large,
• smaller,
• natural,
• tidal,
• important,
• edible,
• common,
• aquatic,
• native,
• commercial,

Simple categories matching intertidal:

• arthropod,
• invertebrate,
• structure,
• shellfish,
• organism,
• herbivore,
• creature,
• system,
• snail,
• animal,
• gastropod,
• mollusc,
• fauna,
• prey,
• mollusk,
• bivalve,
• species,