Intertidal Ecosystem

What does intertidal mean? Between the tides -Intertidal Ecosystems: land between the high tide and low tide

What do all intertidal ecosystems have in common? -Constantly changing environment -Submerged part of the day -Exposed part of the day -Home to extremophiles

Two Major Types -Rocky Intertidal -Sandy Shores

Rocky Intertidal

Observe Rocky Intertidal

Key Characteristics of the Rocky Intertidal Foundation: Bare rocks and/or rocks covered in algae -At low tide, the rock is exposed leaving tidepools

Key Characteristics of the Rocky Intertidal Tidepools: As the water ebbs to reach low tide, pools of water are left behind in the crevices created by the rocks

What environmental stressors do organisms of the Rocky Intertidal? Waves Temperature changes Salinity Changes Air exposure Dessication Fully submerged

Sandy Shore Intertidal

Observe Sandy Shore Intertidal

Key Characteristics Foundation: - sand grains, crushed shells, smaller pebbles Usually bordered by coastal grasses and plants Reshaped Daily, how?

Sand Can be classified by : Grain size Color Composition Morphology (angularity and shape) Surface texture

It’s not all it appears to be

It’s not all it appears to be

Environmental Issues

Beach Combing -Individuals or groups taking things of interest from the beach How can this have a negative impact on the environment?

Removal of Beach Wrack Beach Wrack: Seaweed that is brought in by the tides and left on the beach -People will remove beach wrack because it is not visually appealing Why do you think removing beach wrack can have a negative affect on the environment?

Trespassing onto Sensitive Breeding Areas Many endangered birds and turtles breed on the sandy shore -If people are not careful, they can trample and destroy birds nests and turtles nest

Organisms of the Intertidal

Organisms of the Intertidal Seaweed (kingdom Protista) Class Bivalvia (phylum Mollusca) Class Gastropoda (phylum Mollusca) Class Crustacean (phylum Arthropoda) Phylum Echinodermata

Phycology: The study of seaweed Three different types of seaweed: Phylum Ochrophyta Phylum Rhodophyta Phylum Chlorophyta What commonality do you see in the names? Phyta: plank like (photosynthesizers) What differences do you see in the names?

Phycology: The study of seaweed Three different types of seaweed: Phylum Ochrophyta (Brown Seaweed, middle) Phylum Rhodophyta (Red seaweed, deepest) Phylum Chlorophyta (Green Seaweed, most shallow) Thinking about light, why might you find green as the shallowest and red as the deepest?

Phylum Chlorophyta (Green Seaweed) -Chlorophyll makes them green -Attach to rocks in the Rocky Intertidal -Acts as a primary producer

Human Use of Green Algae -Method of helping to cure cancer -Biofilter -Food -Biodiesel

Gastropoda: What do you observe?

Gastropoda -“stomach foot” -Soft body usually surrounded by one shell -Some have completely lost their shells (sea slugs)

Gastropoda Anatomy If Shell is present Torsion: shell and body is coiled Operculum: Trap door that can seal the snail in its shell

Nudibranchs the Unshelled Gastropoda -Nudi: Naked, Branch: Gills, Naked Gills New Defenses: -Ink -Swimming -Noxious Chemicals -Strong Senses

Crustaceans

Crustaceans -Exoskeleton and jointed appendages

Crustacean Growth -Crustaceans grow but their exoskeleton does not grow with them Solution: Molting Peels back the carapace and crawls out of the old exoskeleton Finds a place to hide while it hardens Shell hardens and Crustacean is mobile again

Bivalvia: Clams, Scallops, Mussels, etc. What do you observe?

Bivalvia -Two Shells that encloses a soft body -Shells are mirror image of each other (bilaterally symmetrical) -Usually (not always) sedentary

Bivalve Anatomy Mussel Gills: Used for breathing and feeding Adductor Muscle: enables bivalves to tightly shut their shells Mantle: Fleshy body of the mussel. Foot

What do the rings mean?

Importance to Intertidal Communities? Why might the second picture be more productive than the first picture? What are the mussels doing to enhance the environment?

Importance to Intertidal Communities? -Bivalves, especially Mussels, colonize and cover the rocks Providing food Provides texture for the rock meaning more space for other organisms to live

How to tell of a Bivalve met its fateful end Sea Otter Crab Moon Snail Sea Star

Invasive Species -Species that are non-native to a specific location -Thrive in the new environment Outcompete native species for food No natural Predators Can potentially destroy an environment

Freshwater Invasive Species -clog pipes -increase drag on boats -sink buoys Introduction: Ship Ballast water https://tpwd.texas.gov/education/hunter-education/online-course/wildlife-conservation/invasive-aquatic-species

Echinodermata “Spiny Skin” -Pentaradial Symmetry -Hydrostatic skeleton for movement -Can sense light and dark -have the ability to regenerate

Major Groups of Echinoderms -Sea Stars -Sea Cucumbers -Sand Dollars -Sea Urchins -Feather Stars

Sea Star Anatomy Coloring https://s-media-cache-ak0.pinimg.com/originals/a3/05/13/a305137f511090e593a09694d11edac0.jpg

Overarching Question Should we restrict people’s access to intertidal ecosystems to keep biodiversity?

Case Studies Human Impact on Intertidal Zones Tourism