Open Ocean Zone

1. Open Ocean Zone Ms. Bridgeland 6th grade

2. Open Ocean Zone: • Begins where the Neritic Zone ends AT THE END OF THE CONTINENTAL SHELF. • How is the Open Ocean Zone different from the Neritic Zone?

3. 2 Ways the Open Ocean Zone is different from the Neritic Zone • 1) Most of the Open Ocean zone is DARK and does NOT receive sunlight. • 2) The water has fewer nutrients because fewer organisms can survive in these conditions.

4. The Open Ocean is divided into 3 zones: • 1) Surface Zone • 2) Transition Zone • 3) The Deep Zone

5. 1) The Surface Zone • Extends as far as sunlight reaches below the surface. • The only part of the open ocean that receives enough sunlight to support the growth of algae. • This algae is the base of the open-ocean food webs • Animals such as krill, baby crabs, mollusks, and fish feel on this algae

6. 2) The Transition Zone • Extends from the bottom of the surface zone (begins at the point that sun does not reach anymore) to the depth of about 1 kilometer. • The water here is darker and colder than the surface zone • This zone is the “transition” from the surface zone to the deep zone

7. 3) The Deep Zone • The water is the darkest and coldest of the three zones • Few organisms can survive the harsh conditions • Many deep sea creatures produce their own light

8. Deep Sea Zone Adaptations • There are fewer nutrients and opportunities to find food, so animals in this zone must be good HUNTERS

9. Bioluminescence: • When deep sea fish produce their own light is called bioluminescence • Bio means “life,” lumin means “light”

10. How do Bioluminescent Animals produce light? • In some bioluminescent animals, light is produced by bioluminescent bacteria that live on their bodies • In other bioluminescent animals, chemical reactions take place in the bodies of the fish, just like fireflies on land • Other fish have light-producing organs

11. Anglerfish • The anglerfish is a bioluminescent deep sea organism that produces its light through a light organ on its head • The anglerfish hides in shadows behind its light organ • Shrimp and fish attracted to its light become its prey

12. Hydrothermal Vents • One kind of deep-zone environment that supports organisms of an unusual number, variety, and size • In a hydrothermal vent, hot water rises out of cracks in the ocean floor • The rising water has been heated by hot rock magma beneath the ocean floor • These vents are location along ocean ridges where the plates are diverging and seafloor spreading is occurring

13. Hydrothermal Vents • The heated water from a vent carries gases and minerals from the Earth’s interior • Bacteria feed off of these chemical nutrients • In the Hydrothermal Vent, bacteria forms the base of the food web • Other organisms such as giant clams feed off of the bacteria

14. Hydrothermal Vents • Animals that live in Hydrothermal Vents: Giant tube worms, shrimp, octopi, Pompeii worm, mussels, clams Pompeii Worm