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Estuaries – Where salt meets fresh. What are estuaries?. Estuaries are… Partially enclosed bodies of water where freshwater from streams and rivers mix with saltwater from the ocean/sea Transition points from land to sea and from fresh to salt water.
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What are estuaries? • Estuaries are… • Partially enclosed bodies of water where freshwater from streams and rivers mix with saltwater from the ocean/sea • Transition points from land to sea and from fresh to salt water. • Tidally driven, but sheltered from the full force of the ocean’s wind and waves by reefs, barrier islands, sand, or mudflats • Transition zones between the marine-dominated systems of the ocean and the upland river systems • Among the most biologically productive ecosystems on Earth Picture of the Rio de la Plata http://en.wikipedia.org/wiki/Estuary
Salt meets fresh Picture from www.narrabay.com/empact/waterQualityInfo.asp • Freshwater is lighter than seawater and therefore flows above it forming a bottom layer of salt water called a salt wedge • Nutrients carried in from salt wedge transform estuaries into very fertile areas for plant growth
Plant life in estuaries Picture from http://www.hww.ca/hww2.asp?pid=0&id=226&cid=2 • There is more plant life in an estuary than any other habitat 1 hectare = 10000 square meters
Animals in estuaries • Estuaries contain many organisms • Some animals living in estuaries include: • sea turtles, sea lions, mussels, clams, scallops, shrimp, snails, amphipods, segmented worms, lugworms, and fish • More unique animals include: horseshoe crabs, ospreys, manatees, and mangroves • Only a few species of organisms live their entire lives in estuaries. Other wild animals live there at some stage of their lives. Some fish spawn in estuaries and certain species of sandpipers migrate to estuaries and some point in the year. http://sticksoffire.com/2007/08/17/preserving-bullfrog-creek-and-history/ http://kentsimmons.uwinnipeg.ca/16cm05/1116/33-28-HorseshoeCrabs.jpg
Plants in estuaries • Sea grass, lyngbyei’s Sedge, saltwort, eelgrass, cordgrass (on Atlantic Coast), alkali grass (in the Arctic), and algae • Because plants have different tolerance levels for salt, most types of plants flourish in different areas of an estuary.
Estuaries around the world Estuaries in the U.S. include Chesapeake Bay, San Francisco Bay, Boston Harbor, Tampa Bay and Puget Sound
Human impact • In the past, many people believed estuaries as wasted land and thus built dams. Dams block natural stream and river routes thus cutting off freshwater from estuaries. When that happens, the fresh and saltwater balance of the estuary is changed and estuary wildlife is damaged. • Increased human growth has added more nutrients to estuaries (mainly from sewage), which has contributed to marine animal disease, and toxic algal blooms. • Seafood safety has now become a concern because certain shellfish and fish have been infected with algal toxins capable of paralytic or diarrhetic effects on humans. Toxic algal bloom at Lemolo Lake Kumgang Estuary Dam in South Korea kalaniosullivan.com/Korea/KunsanCity/Kunsan3.html
An endangered specie • The Florida Manatee is under protection from the Endangered Species Act of 1973. • Found in Florida and southwestern Georgia in estuaries • The main cause of this is human intervention. • Hunting has greatly reduced the population • Pollution by humans has killed a lot of seagrass and other aquatic foods which the Florida Manatee feeds on. • Population growth and city development has destroyed much of the manatee habitat • Manatee collisions with watercrafts accounted for 78 deaths in 2000. • In October 2007, the IUCN stated that there were less than 2500 mature individuals of the Florida Manatee. http://www.naturesresortfla.com/images/manatee1.jpg
What is so unique/important about estuaries? • Estuaries are more than just a place for animals and plants to live. They also help control pollution. Water from upland areas often carries sediment and pollutants. The marshy land and plants in estuaries filter these pollutants out of the water. • Estuaries also protect inland areas from flooding and storm surges. When a storm hits, estuaries often absorb water from the storm before it can reach upland areas.
South Carolina Estuaries • Ace Basin Reserve • Winyah Bay • Port Royal Sound
Multiple Choice Question #1 What is an estuary? • One of the least productive ecosystems in the world • A habitat for only a few species able to adapt to the environment • Transition zone between oceans and seas • Where saltwater from the ocean/sea mix with freshwater from rivers/streams • All of the above
Multiple Choice Question #1 The correct answer is: • One of the least productive ecosystems in the world • A habitat for only a few species able to adapt to the environment • Transition zone between oceans and seas • Where saltwater from the ocean/sea mix with freshwater from rivers/streams • All of the above
Multiple Choice Question #2 Why are estuaries important to the environment? • They help control global warming • They help control pollution • They protect inland areas from floods and storms • A, B and C • B and C
Multiple Choice Question #2 The correct answer is • They help control global warming • They help control pollution • They protect inland areas from floods and storms • A, B and C • B and C
Multiple Choice Question #3 What are some of the animals that live in an estuary? • Only plants live in estuaries • Kangaroos, Tasmanian devils, and Wombats • Fish, shellfish, horseshoe crabs, and birds • Scorpions, sea snakes, snails, and bats • Shrimp, shellfish, sharks, chickens, and marlins
Multiple Choice Question #3 The correct answer is • Only plants live in estuaries • Kangaroos, Tasmanian devils, and Wombats • Fish, shellfish, horshoe crabs, and birds • Scorpions, sea snakes, snails, and bats • Shrimp, shellfish, sharks, chickens, and marlins
Multiple Choice Question #4 Which of the following species is an example of an endangered specie in estuaries? • Horseshoe crab • Indian Western Manatee • Western Sandpiper • Florida Manatee • Whitefish
Multiple Choice Question #4 The correct answer is • Horseshoe crab • Indian Western Manatee • Western Sandpiper • Florida Manatee • Whitefish
Multiple Choice Question #5 How have humans impacted estuaries? • Hunting manatees • Crashing into manatees with water vehicles • Pollution of manatee waters • Destruction of manatee habitat • All of the above
Multiple Choice Question #5 The correct answer is • Hunting manatees • Crashing into manatees with water vehicles • Pollution of manatee waters • Destruction of manatee habitat • All of the above
References • http://www.estuaries.gov/about.html • http://www.inforain.org/mapsatwork/oregonestuary/ • http://inlet.geol.sc.edu/estecohp.html • http://www.hww.ca/hww2.asp?pid=0&id=226&cid=2 • http://wps.prenhall.com/esm_thurman_introocean_9/0,7305,348196-,00.html • http://www.epa.gov/owow/estuaries/kids/about/what.htm • http://www.fws.gov/northflorida/Manatee/manatee-gen-facts.htm