What is Estuary?
An '''estuary''' is where a [[river]] meets the [[sea]]. There, [[saltwater]] mixes with [[freshwater]]. The river becomes wider and wider and flows slowly to the [[ocean]]. [[Bay]]s, [[marsh]]es, [[swamp]]s, and [[inlet]]s can all have estuaries. A view of an estuary from the air is usually an interesting sight: many estuaries [[meander]] (curve and bend) to find their way to the sea. Estuaries come in all sizes and shapes, each according to its location and [[climate]]. Where rivers meet the [[sea]] and fresh water mixes with salt water, the mixture is called [[brackish water]]. Some estuaries are very large. They may be large ocean bays that have more than one river flowing into them. For example, [[Chesapeake Bay]] is a large estuary, and several different rivers meet the [[Atlantic Ocean]] there. In simple terms it is where a river meets with a large body of water, only with one outlet and not many like a delta. == Habitat == Estuaries are usually filled with shallow waters, and sunlight reaches all levels of the water. [[Marsh]] grasses, [[algae]], and other kinds of plants live in estuaries and provide food for a variety of fish, [[crab]]s, [[oyster]]s, and [[shrimp]].<ref name=Pous>Pous, Dinorah 2003. ''Blue Planet''. McGrawHill.</ref> Estuaries are especially important since they act as nurseries for many different types of young fish and other animals before they head out toward the open ocean.<ref name=Pous/> Many sea birds also [[nest]] in estuaries. The United States government has a program to study and protect the natural environment in many different estuaries, called the National Estuarine Research Reserve System. One reason that the natural environment in so many estuaries is in danger is because they are also good places for people to live and build cities. Unfortunately, many of world's largest [[city|cities]] are at or near estuaries. == References == {{Reflist}} {{geo-stub}} [[Category:Bodies of water]] [[Category:Ecosystems]]