Estuaries and Coral Reefs

1. Estuaries and Coral Reefs Chapters 3.4 and 3.5

2. Estuaries • Estuaries are formed where a freshwater river empties into an ocean. • The resulting water is brackish – a mixture of fresh and saltwater • 3 main types: 1. salt marsh or wetland, 2. mud flat or 3. mangrove swamp. • May form what we call a bay.

3. Wetlands (Salt Marsh) • May be protected by barrier beaches which were formed by the retreat of glaciers. • Barrier beaches protect the bay from ocean winds and waves. Ex. LBI, Seaside, Brigantine, Wildwood, etc. • “Nurseries of the sea”

4. Wetlands (con’t) • Grasses, like cordgrass, are specially adapted to the salt – glands that excrete salt • Some marsh grasses actually filter pollution • Crabs, fish, mussels, barnacles live here

5. Salt Marsh – Delaware Bay

6. Mudflats • “Graveyards of the sea” • Very stinky mud caused by bacteria breaking down dead and decaying material and releasing SO2 – which smells like rotten eggs. • Very rich, dark sand because there is little flushing (water moving in and out). • This is where clams come from

7. Mudflat – Delaware Bay

8. Barrier Beaches of NJ

9. Mangroves • Tropical bays and inlets covered by a thick growth of mangrove trees. • Red, white and black mangrove trees • Prop roots stick above water during low tide.

10. Mangroves (con’t) • Roots trap lots of nutrients making the mangroves a very rich environment • Natural buffer to weather disasters

11. Mangrove

12. Coral Reefs • Contain more biodiversity of any other marine ecosystems • Found 30 degrees North and 30 degrees South of the equator • Very sensitive to human influence • Cloudy water, increased or decreased water temperature could kill the reef animals

13. Coral Reef – “Rainforests of the Sea” because of biodiversity

14. Unique Adaptations of Reef Animals • Camouflage • Color contrast – confuses predators • Disruptive coloration – breaks up the outline of the fish • Territoriality

15. Camouflage

16. Color Contrast

17. Disruptive Coloration