Estuaries

Estuaries An Integrated Science Report By: 14- Shannen D. Abenido 16- Angelica Cabañas 21- Joahnna Marie P. Iloreta 23- Christine Angelica Losañes

Description… Estuaries are where salt water from the oceans meet freshwater streams or rivers. The word estuary comes from Latin roots such as aestus (“the tide”) and aestuo (“boil”) indicating the effect when tidal flow and river flow meet. The estuary may also be called bay, lagoon, harbor, inlet, or sound.

Due to dynamite fishing, water pollution and poor waste control, estuaries are disappearing quickly. Almost 22 square miles each year is lost. Estuaries also serve as giant filters for sediments and harmful substances before they damage the environment.

Climate… The climate of a specific estuary depends on its location. For example, the Chesapeake Bay receives a warm climate because it is found in the low-lying areas of the United States as the estuaries in Alaska and Norway have glacier-scoured valleys due to its mountainous coastal regions. Seasonal changes in temperature can be most easily detected in the coastal regions of the mid-latitudes, where surface temperatures are at a minimum in winter and reach maximum values in late summer.

Chesapeake bay

Cook inlet

Geography… Estuaries are mostly found on shorelines of continents, mostly in North and South America. Examples are: 

The Chesapeake bay – off the Atlantic Ocean

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Puget Sound – North Washington, USA Gulf of Saint Lawrence – North America (world’s largest estuary) Cook Inlet – Alaska Barataria-Terrebonne Estuary – New Orleans

Classification Of Estuaries According To Their Origin… Coastal Plain - low-lying coasts with drowned river systems Fjord - glaciated valleys that are U-shaped with steep walls.  They usually have a glacial deposit forming a sill near the ocean entrance. Bar-built - shallow estuaries separated from the open ocean by bars composed of sand deposited parallel to the coast by wave action.  Lagoons separating barrier islands form the mainland are bar-built estuaries.

Animals… Most of the animals found in an estuary are reptiles, crustaceans, mollusks and pelicans. A big number of them are herbivores except for the variety of birds. Pesticides and hunting are two of the reasons for animal extinction in estuaries. Examples: The brown pelican is one of the most fascinating birds in the estuary. With its keen eyesight and 6-foot wingspan, this strangelooking bird can swoop down from a height of up to 70 feet above water to catch fish when it's hungry. It can eat up to 4 pounds of fish each day.

The common spider crab (right) got its name due to its spider-like appearance. This crab is one of the most interesting animals in the estuaries due to its ability to camouflage with its muddy environment.

With its fearsome and powerful claws, the blue crab (left) is another of the estuary's special creatures. It is the mascot of the Barataria-Terrebonne National Estuary Program (BTNEP). They are talented swimmers, propelled through the water with oar-like legs that rotate at 20 to 40 revolutions per minute. This allows them to disappear in a blur at the first sign of trouble. In fact, their scientific name, Callinectes sapidus means “beautiful savory swimmer”.

Plants… The vegetation of the water area of the estuary have various coral reefs and the land area consists of different grasses.. The grasses serve as food for the different animals such as prairie dogs and the like. Examples: Switchgrass (right) is a summer perennial grass that is native to North America. It is a natural component of the tall-grass prairie which covered must of the great Plains. Because it is native, Switchgrass is resistant to many pests and plant diseases, and it is capable of producing high yields with very low applications of fertilizer. It is also very tolerant of poor soils, flooding and drought, which are widespread agricultural problems in the southeast.

Common Reed (right) is a large grass that grows up to 12 feet tall. It has a large stalk, called a culm, which can be an inch thick. The culm is hollow inside. Leaves of Common Reed are long, sharp, and bluishgreen blades. They grow about two feet long and two inches wide. Common Reeds can be very competitive. They will often crowd out other plants, such as cattails. They grow quickly by spreading underground stems, called rhizomes. The Saltmarsh Cordgrass are the wettest of the cordgrasses. They serve as important nurseries for some fish to spawn or rear juveniles. Cordgrass excretes excess salt, which solidifies into crystals on its leaves. This is one way it copes with the conditions of the lower marsh.

QUESTiONS… ¼ paper please! Good Luck! 

Fill in the blanks… 1-2. The word estuary comes from Latin roots such as aestus (“_________”) and aestuo (“____”) 3. Estuaries serve as giant _______ for harmful substances before damaging the environment. 4. The largest estuary in the world is the Gulf of ____________. 5. The _____________ has a 6-foot wingspan and has keen eyesight. 6. The _________ has a scientific name which means beautiful savory swimmer. 7. Almost __ square miles of the world's estuaries are lost each year.

True or False… 8. The Blue Crab is the Mascot of the BTNEP. 9. The Common Reed grass is very competitive. 10. The Saltmarsh Cordgrass is the driest of the cordgrasses. 11. Estuaries are the largest of the world’s biomes. Enumeration… 12-15. Give the 4 classifications of estuaries according to their origin.