The Estuary: where fresh and saltwater mix
Estuaries and their surrounding wetlands are bodies of water usually found where rivers meet the sea. Estuaries are home to unique plant and animal communities that have adapted to brackish water — a mixture of fresh water draining from the land and salty seawater.
Estuaries are among the most productive ecosystems in the world. Many animals rely on estuaries for food, places to breed, and migration stopovers.
Human communities also rely on estuaries for food, recreation, jobs, and coastal protection. Of the 32 largest cities in the world, 22 are located on estuaries!
Estuaries are delicate ecosystems. Congress created the National Estuarine Research Reserve System to protect more than one million acres of estuarine land and water. These estuarine reserves provide essential habitat for wildlife, offer educational opportunities for students, and serve as living laboratories for scientists.
The Chesapeake Bay is the largest estuary in the United States.
The Chesapeake Bay is the largest estuary in the United States and is one of the most productive bodies of water in the world.
The Chesapeake watershed* spans 64,000 squares miles, covering parts of six states — Delaware, Maryland, New York, Pennsylvania, Virginia, West Virginia, and the District of Columbia. Over 17 million people live in this area.
(*A watershed is the area of land where all of the water that is under it or drains off of it goes into the same place.)
The estuary and its network of streams, creeks and rivers hold tremendous ecological, cultural, economic, historic, and recreational value for the region.
More than 250 fish species use the Bay and tributaries for some portion of their life cycles, including American and hickory shad, river herring, striped bass, eel, weakfish, bluefish, flounder, oysters, and blue crabs. More than 300 migratory bird species can also be found in the watershed. During the fall, the skies come alive as one million ducks, geese, and swans return to overwinter on the Chesapeake.
The Chesapeake watershed is a complex network of wetlands, forests, fields, streams, underwater grasses, and mudflats that provide thousands of species of plants, fish, and wildlife with the places they need to find food, shelter, reproduce, and rear their young. The Chesapeake also provides "habitat highways" for Atlantic Coast fish populations and birds migrating along the Atlantic Flyway. These habitats play an important role in filtering pollution before it enters waterways.
Bay wetlands serve as holding tanks and water filters for coastal storm surge and heavy rainfall and help prevent costly flood damage. Forest buffers along streams and shorelines provide shade to keep streams cool, food for aquatic organisms and corridors for wildlife movement. Streams are the arteries that connect the watershed and provide not only passage for fish, but also a physical connection from every local community to the Bay.
Today, the Bay and its tributaries are in poor health, with polluted water, low populations of fish and shellfish, degraded habitats, and landscapes lost to development. In recognition of this, President Obama issued an Executive Order in 2009 to protect and restore this important area. In the Order, the President declared the Chesapeake Bay a "national treasure" and ushered in a new era of federal leadership, action and accountability to "protect and restore the health, heritage, natural resources, and social and economic value of the nation's largest estuarine ecosystem and the natural sustainability of its watershed."
Estuaries are one of the most productive ecosystems in the world, so there is a great diversity of animals and plants that live there
Estuaries - areas where fresh and saltwater mix - are made up of many different types of habitats. These habitats can include oyster reefs, coral reefs, rocky shores, submerged aquatic vegetation, marshes, and mangroves. There are also different animals that live in each of these different habitats. Fish, shellfish, and migratory birds are just a few of the animals that can live in an estuary.
For example, there are several habitats that make up the Chesapeake Bay. There are oyster reefs where oysters, mud crabs, and small fish may be found. Also in the Chesapeake Bay, there is submerged aquatic vegetation where seahorses, blue crabs, and other fish live. Finally, there is open water where sea turtles or rays can be found.
Changing conditions are a necessary part of healthy, functioning estuaries
Estuaries experience change many times a day due to tides.
Estuaries are tidally driven. Tides flush the system and provide nutrients to keep food webs functional. By doing this, tides create constantly changing conditions of exposure to air or increased levels of water in an estuarine environment. Because of tides, the water levels in an estuary are going up and down several times a day.
Estuarine organisms can adapt quite well to these changing conditions in estuaries. For example, fish or crabs are mobile and can move as needed throughout the day to adjust to changes in the estuary.
In addition, weather patterns, seasonal cycles, and climate change also affect and can change conditions in estuaries.
Estuaries and their surrounding wetlands are bodies of water usually found where rivers meet the sea. Estuaries are home to unique plant and animal communities that have adapted to brackish water.
The National Estuarine Research Reserve System, or NERRS, is a partnership between NOAA and coastal states to study and protect vital coastal and estuarine resources
National Estuarine Research Reserves serve as "living laboratories," with opportunities for both scientists and graduate students to conduct research. Reserves also conduct long-term water quality monitoring.
The National Estuarine Research Reserve System is a network of 28 areas representing different biogeographic regions of the United States. The reserves are protected for long-term research, water quality monitoring, education, and coastal stewardship. Each reserve is managed on a daily basis by a lead state agency or university, with input from local partners. NOAA provides funding, national guidance, and technical assistance.
Reserve staff work with local communities and regional groups to address natural resource management issues, such as non-point source pollution, habitat restoration, and invasive species. Through integrated research and education, the reserves help communities develop strategies to deal successfully with their coastal resource issues.
Reserves provide adult audiences with training on estuarine issues of concern in their local communities. They also offer field classes for K-12 students and support teachers through professional development programs in marine education.
The above information about estuaries and the Chesapeake Bay came from http://oceanservice.noaa.gov/facts/
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