Seagrass True flowering plants that can live totally

Seagrass True flowering plants that can live totally submerged in seawater

Seagrass • About 50 species • Abundant in estuaries and shallow, calm waters with sandy or muddy bottoms. • Same basic structure as terrestrial (land) plants. – Flowers, leaves and roots • Produce pollen, but contrary to land plants, pollen spread by currents

Importance of Sea Grasses • Grows very close together providing cover for mollusks, arthropods (crabs), and fish – protection from predators – nursery for small invertebrates and fish • Helps to stabilize sand on bottom • Rich biological communities – few animals (manatees and turtles) eat sea grasses directly. Leaves break free and then is broken down into smaller pieces this material is used by bacteria are then used as a food source by other organisms

Eel grass (Zostera marina): Found in temperate waters (Great South Bay) • usually shallow, calm areas

Eel Grass Bay scallops attach to eelgrass blades when they settle from the plankton. Note threads behind the hinge used to attach to the blade. • Juvenile bay scallops and other attached fauna have a refuge from predators on the upper ends of eelgrass blades.

Many animals climb the eelgrass blades to prey on attached organisms

• Juvenile scup use eelgrass meadows as nursery grounds.

• Reproduces by sexual (pollen grains carried by stigma seeds) or asexual means (rhizomes)

Thallassia: Turtle grass • Found in warmer waters (Caribbean, Gulf Coast from Texas to Florida) • Forms an interlocking mat that helps stabilize the sandy sea-floor • Food source for turtles