1. Ecology, Intertidal Zones, and Estuaries

2. Ecology
Ecology – how organisms interact with each other and their environment
Ecosystem – all living and nonliving factors in a given area

3. Factors in an Ecosystem
Abiotic
Biotic
Population size
Population density
Community types

4. Competition Living together: Symbiosis – close relationships; 3 types
Commensalism +/0
Parasitism +/–
Mutualism (cleaner fish) +/+

5. Flow of Energy in an Ecosystem
Autotrophs – producers
Heterotrophs – consumers
Food chains & Food webs

6. The Intertidal Zone
Intertidal zone (littoral zone) – area between the high and low tides
Subtidal zone – region from the end of the continental shelf to the low tide marker; never is exposed to air

7. Rocky Intertidal Zone

8. Typical Rocky Shore

9. Soft Bottom Shore

11. Substrate Substrate Hard, rocky - (Rocky Shore Intertidal Communities)
Sandy –
(Soft-Bottom Intertidal Communities)
Muddy –

12. Vertical Zonation on a Rocky Shoreline
Vertical Zonation (4 zones):
Spray
Highest reach of spray & storm waves to high tides
Infrequently wetted
Organisms: lichens, encrusting algae, sea hair, limpets
Upper
From upper region of high tides to sea level
Organisms: acorn barnacle, shore crab, limpets, rockweed, snails

14. Vertical Zonation (cont.)
Middle
Covered & uncovered 2 times per day
Semidiurnal tides
Organisms: surf grass, sea anemones, mussels, sea stars, barnacles
Lower
Usually submerged except for a few hours each month
Organisms: kelp, sea stars, sea urchins, chitons

16. Stressors in the Intertidal Zone
Water loss (desiccation)
Temperature changes
Salinity changes
Wave shock

17. Solutions to Dealing with the Stressors
Desiccation
3 strategies for dealing with H2O loss
“run-and-hide” – (crevices/tide pools)
“clam-up”
“dry-out” – (seaweeds)
Temperature
Just Be Tough (like me)
Radiating structures
colors

18. Some animals allow themselves to just dry out
A chiton has the ability to loose 70 percent of its water and still survive

19. Light color reflects light
Ridges allow heat to escape

20. Solutions to Dealing with the Stressors
Salinity
Tough
Burrow / “clam-up”
Wave shock
Holdfasts (seaweeds)
Byssal threads (mussels)
Muscular foot of snails
Low profile
Hiding

21. Estuaries
Estuaries – enclosed areas where freshwater & saltwater meet & mix (ex. bays, lagoons, deltas)

25. Physical Characteristics of Estuaries
Salinity – 0% - 35%
Extreme salinity changes
Salt wedge – salinity changes at different depths due to density differences.

27. Substrate – deposition of fine particles
Commonly soft mud
Low 02 due to high organic matter & decomposing bacteria
Results: odor (egg smell; sulfur); black
Fluctuating temperatures

28. Types of Estuary Communities
Open H2O
Fauna: Anchovies, mullets, anadromous & catadromous fishes (Shad, Eels,
Striped Bass)
Mud flats
Very few plants
Fauna: fiddler crabs, clams, mussels, oysters, ghost shrimp, pipe fish, silver sides, polychaetes,
Predators: birds & fishes

30. Type of Estuary Communities (cont.)
Salt marshes
Plants: cord grasses
Bacteria
Ex. Cape May, New Jersey
Mangrove forests
[R]: propugules; H2O
[B/W]: inland; pneumatophores
Fx: habitat / protect shorelines