Rivers+and+Streams

=Rivers and Streams =



General Information on Rivers and Streams
ever there is a water source and in a variety of terrains (usually downhill). Both streams and rivers usually contains flowing freshwater and are very dependent on availability of water, temperature, and land terrain. These life zones can experience all four seasons depending on the actual location (rivers further north or in very cold areas can freeze over during the winter). Rivers and streams can carry a variety of things such as bacteria, rock sediments, sticks leaves, boulders,and whatever falls into them.
 * Streams** are small bodies of water that flow in channels. **Rivers** by definition are larger streams that carry water to larger bodies of water such as lakes and oceans.Both bodies of water can be found throughout the world where

** Native Species **
The specific native species for rivers and streams depend a lot on the location of these flowing bodies of water. .Native species are species of living organisms that normally live in a particular environment. One native species of the Delaware River is the American Shad.The **American Shad** is one of the largest herring fishes are a abundant in rivers all over the east coast of the United States. This kind of fish spends a majority of its time in salt water environments but spawn in freshwater. A female American shad can lay anywhere from 100,000 eggs to 600,000 eggs in the water after being fertilized by multiple males. The American shad typically lives about six years in the ocean until they reach sexually maturity and return back to the freshwater to finish their life cycles. It is a very important food source for bigger fishes like bluefishes, and are economically important to fishermen all along the east coast.

** Non-Native Species **
Non-native species are living organisms that either migrated or was introduced to a ecosystem that they do not belong in, and could either affect the new environment or not affect anything. One kind of invasive species in the Delaware River is the brown trout. The **Brown Trout** is a large fish with large black and red spots with a pale border on its skin. This type of fish spawn near headwaters in the late fall and can grow up to eight to ten pounds fully matured. The Brown Trout has a negative impact on the Delaware River because it feeds on the native fishes in the river and increases competition for food sources

.

** Indicator Species **
Indicator species are living organisms that serve a important role in their ecosystems. They act almost as a warning of damages sustained by the community or impending dangers to the community. There are multiple kinds of indicator species, but the most abundant species are the birds that live near the Delaware River. When the population of bird species begin to decline, this usually means that the dramatic changes to the environment such as the introduction of new chemicals or destruction of habitat.

** Keystone Species **
Keystone species are species of living organisms that a community needs to stay "healthy" and have important effects on the environment and the other organisms living in the area. A important keystone species of the Delaware River is the **Horseshoe Crab.** The Delaware River has one of the largest population of spawning horseshoe crabs. These crabs are keystone species because the eggs the female crabs lay are important food sources for millions of birds migrating northward in the spring. The horseshoe crab's eggs feed up to thirty species of birds. Without the horseshoe crab's eggs, these birds would starve while on their northward migrations during the spring.

** Inter-species Competition Avoidance **
====There are many types of fish that swim in the rivers for example Trout, Bass, and Salmon. Competition is avoided by these fish species because salmons spend a majority of their lives in the open oceans,but return to the rivers and streams to breed. Because the salmon spends most of their lives in the ocean, this reduces the competition for resources such as food between the salmons and other fish species.====

** Predator- Prey Relationship **

 * One example of the predator prey relationship in rivers in between the Grizzly Bear and fish like Salmon.The salmons spend most of their lives in the open oceans feeding and growing, and then return back to the streams and rivers where they were born to breed. The grizzly bears flock to nearby rivers and streams for a feast of salmons. They feed on the salmons therefore keeping the number of fish breeding stable. This in turns affect the number of eggs laid and number of individual fishes that become adults to repeat the cycle. **

** Symbiotic Relationships **
A symbiotic relationship in a river is when rain water leeches nutrients and chemical from soil. That soil feeds the plants and algae growing along the riverbanks. These plants and algae provide many creatures such as clams food to live off of and the clams filter the algae. Water carries the salts out to the sea and shellfish extract calcium. Dead shellfish deposit their shells to become rock. That is a symbiotic relationship in rivers.

** Current Event Article **
Recently scientists working in the Delaware River around Trenton and Philadelphia found large colonies of a mussel species that was long thought to be extinct. Mussels serve as an important indicator of the health of the river. Mussels help filter out impurites in the water and are important to improving water quality. The size and diversity of these mussels mean that the water quality of the Delaware is better than what people would normally think. Currently scientists are trying to breed these newly discovered mussels around other areas in the Delaware River, where mussels previously existed,but have been wiped out.

link to article: http://www.newsworks.org/index.php/yorg-homepage/item/7556-17cbmussels

__** Sources Used **__

 * http://www.bio.umass.edu/biology/conn.river/shad.html
 * http://www.fws.gov/chesapeakebay/SHAD.HTM
 * http://fl.biology.usgs.gov/Region_5_Report/html/species_accounts.html
 * http://www.cumauriceriver.org/downjersey/natural/n-lesson13.html
 * http://www.newsworks.org/index.php/yorg-homepage/item/7556-17cbmussels
 * http://www.nps.gov/dewa/naturescience/fish.htm
 * http://www.natureserve.org/publications/riversOflife.jsp
 * http://chamisa.freeshell.org/ecology.htm
 * http://www.eoearth.org/article/River
 * http://www.biology-online.org/6/4_abiotic_factors.htm
 * http://library.thinkquest.org/05aug/00548/species--life%20cycle.html
 * http://www.ecy.wa.gov/programs/sea/pugetsound/species/salmon_cyc.html

** Pictures obtained from: **

 * http://www.nauticalpassion.com/wp-content/uploads/2008/06/bridge-sm.jpg
 * http://www.bio.umass.edu/biology/kunkel/fish/albatross-iv/al0103/fish0670.jpg
 * http://guideontroutfishing.com/wp-content/uploads/2010/07/BrownTrout-copy.jpg
 * http://locad.nasa.gov/images/pages/crabs.png