1. Marine Food Webs
A complex ecosystem

2. A marine food web

3. Trophic levels

4. A trophic level is the level at which a particular organism feeds in the ecosystem.
Energy and biomass is lost at each level because not all is consumed. About 90% of an organisms energy goes into its daily life processes and therefore is not passed on.

5. Making a food web
The task is to come up with a food web containing all of the following organisms and at least 11 links.
Blue shark
Dinoflagellate
Zooplankton
Eelgrass
Atlantic Herring
Bluefin tuna
Canada goose
Human
Mysid shrimp
Blue Whale

6. Symbiotic Relationships
There are three types of symbiotic relationships that can exist between two organisms:
Mutualism
Both organisms benefit from the relationship-
eg - remora fish with sharks and rays
- clownfish and coral or sea anemones.

7. When a predators comes to nibble on the anemone, the clownfish rushes out and drives it away.
The clownfish hides in the somewhat poisonous anemone tentacles from its predators.

8. Remora and shark

9. Commensalism
One organism benefits and the other is unaffected (neither harmed or helped).
Eg. Barnacles on whales or crabs

10. Parasitism
One organism (the parasite) benefits from the host, and the host is harmed.
Eg. - Ascaris worm in codfish
- Sea lice on Atlantic Salmon