- Bacterioplankton
- planktonic bacteria
- Baleen
- keratin plates or slats found in mystecyte whales that hang transversely from the roof and have fringed inner edges used in filter feeding
- Barbel
- a threadlike growth hanging from the lips or lower jaw of certain fishes; a touch organ. Prominent in cod and catfish.
- Benthic
- near or on the bottom of a body of water
- Benthos
- organism living on the ocean floor
- Bilateral symmetry
- arrangement of body parts in which if the animal is divided along the midline, there are two halves that are approximately equal mirror images of each other
- Bioaccumulation
- absorption and accumulation of toxic chemicals in living organisms. Toxins are stored in fatty tissues of animals and are passed along to their predators
- Biogeographic
- geographical distribution of plants and animals
- Bioluminescence
- production of visible light by living organisms using a chemical process; light produced is 'cold light'
- Biomass
- total weight of living organisms or population in a given area or volume
- Biome
- major plant and animal community characterized by climatic and soil conditions
- Biota
- plants and animals of a region
- Biotic
- factors pertaining to life; living
- Bipedal
- two-footed; to walk on two feet
- Bivalve
- any member of the Class Bivalvia of mollusks having two valves or shells hinged together, e.g., mussel, clam, oyster or
- Blade
- leaf-like part of seaweed
- Blubber
- layer of fatty tissue below the epidermis (skin) of some marine mammals
- Boreal
- northern
- Brachiation
- using primarily the arms for locomotion
- Brackish water
- water that is mixture of salt and fresh water in differing amounts; in salt marshes usually 12-18 parts salt/1000 parts water
- Broadcast
- release of sperm and egg into the water where fertilization and development may occur
- Browser
- animal eating leaves and twigs from shrubs and trees; aquatic from rocks and coral
- Budding
- swelling or projection on the body of some lower animals that develops into a new individual; form of asexual reproduction
- bycatch
- unwanted marine creatures that are caught by fishing gear while fishing for another species. or the NMFS definition: discarded catch of any living marine resource plus unobserved mortality due to a direct encounter with fishing gear.
