1. The Subtidal1 Life on the Continental Shelf

2. The Subtidal2 The Continental Shelf

3. The Subtidal3 Sampling the Benthic Habitat Bottom trawlsGrabsDredges

4. The Subtidal4 The Continental Shelf What we know about this community: Very few species are dominant and constitute most of the biomass Parallel bottom communities Many analogies can be drawn to similar areas Different species but are ecologically equivalent These communities are extremely stable over time Animals are distributed in a patchy manner and organisms occur at various depths in the substrate

5. The Subtidal5 Abiotic Factors Species distribution varies from the poles to the tropics Shallow water is affected by currents and wave action Nutrients are not limiting

6. The Subtidal6 Soft-bottom Subtidal Communities This substrate dominates the worlds continental shelves Animals are distributed in this community based on sediment particle size, stability of the sediment, light and temperature Organisms usually occur in patches, due to planktonic settlement Metamorphose and “tasting settlement sites”

7. The Subtidal7 Unvegetated Soft-bottom Communities Notable is absence of large plants and algae There is little primary production so the filter feeders and suspension feeders rely on detritus brought from estuaries Deposit feeders and bacteria dominate fine sediments due to high organic content

8. The Subtidal8 Seagrass beds Areas that are carpeted by flowering plants They develop best in sheltered shallow areas along the coast Eel grass is our most common representative

9. The Subtidal9 Seagrasses Thick mats of eel grass provide lots of habitat for animals to hide By stabilizing the sediment it decreases the turbidity Dead sea grasses provide lots of detritus that benefit suspension, deposit and filter feeders

10. The Subtidal10 Sea Grass Food Web

11. The Subtidal11 Rocky subtidal bottoms and Kelp Forests Animals that are present have the same characteristics as those of the rocky intertidal Kelp is a macroalgae which can reach amazing sizes

12. The Subtidal12 Kelp and Kelp Forests