Survey of Oceanography
Yasuo7776
33TheBenthos.pptxThe Benthos
By: John Van Leer
April 19, 2019
Exposure to air increases with elevation within the intertidal zone.
Typical West Coast intertidal species. Shellfish above water are safe from starfish predation.
Barnacles filter feed while Snails and limpets graze the algal coatings.
Anemones are often mistaken for plants. Sea worms are excellent bait.
Soft bottom creatures include several commercial shellfish species and crabs. The sea pen is another animal that looks like a plant.
More soft bottom species including cockles and burrowing shrimp. Clams use twin snorkels to breath and feed.
Seaweeds need no circulatory system since they are immersed in sea water.
Many seaweed species use trapped gas bubbles to lift their fronds closer to the light.
Common coral reef dwellers include many animals that look like plants.
Brightly colored reef organisms use color for identification and as warnings. Corals build structures of limestone for protection. We have lost nearly half the coral cover on earth, to bleaching and acidification.
Individual coral polyps look like miniature sea anemones, at night.
Shallow water corals show evidence of bleaching when corals are exposed to 30 degree C or higher temperatures. They expel their symbiotic algal cells containing chlorophyll.
Barrier reef systems are the largest biolically created structures on earth.
Fouling organisms encrust a coastal mooring in shallow water.
Fouling organisms encrust oceanographic sampling gear.
a) Sea Anemone. b) Sea Slug. e) Starfish.
f) Starfish opens clam with tube feet. g) Sea urchins graze algae. h) Sea urchin mouth. i) Pink sea scallops filter feed.
Tube worms from deep sea vents cluster near the hot water source.
Bottom dredge is a very crude method of benthic sampling. Scuba diving would be far less destructive.
Benthic communities in the Bering Sea include high value species like King Crabs.
Oysters and mussels can be grown in 3 dimensions on vertical wires in rich coastal waters.
