Water pollution throughout the world is affecting food chains and food webs. Water such as lakes, rivers, streams, creeks, and oceans become polluted in many different ways. One main way is the dumping of trash, or littering. Many creeks, rivers, and even oceans have been polluted by man made items such as trash (EPA, 2011). When fresh water such as rivers and creeks become polluted, it hurts the surrounding wildlife. Trash can collect and begin to clog creeks, which stop fish from swimming upstream and downstream to spawn, thus depleting the amount of fish, which could eventually lead to the loss of an entire population. As trash collects, it also can block sunlight which can lead to the death of some plant life within the water (Water Pollution, 2011).
In turn, the decrease of fish population due to pollutants such as trash, and even harmful chemicals, affects the entire food chain surrounding it (EPA, 2011). Birds of prey such as bald eagles and hawks, live off of, and eat fish. As fish populations begin to deplete, then that effects the bird population because the birds have no food to eat. Since fish generally live off of insects, there is a rise in the insect population since they are not being eaten. There is also the risk of disease or health issues effecting fish. Since there are so many chemicals running into and polluting water, this can cause fish themselves to be contaminated (EPA, 2011). This poses a threat because the birds that then eat these contaminated fish can gain their own health problems, thus also causing a decrease in the population of birds.
Last year in 2010, there was a major water pollution event that occurred. Tons of oil were released into the Gulf of Mexico, and killed the surrounding wildlife. More than 6,000 animals were killed such as birds, fish, turtles, and dolphins. With such a large death of birds, there were fewer animals to prey on fish, which meant a rise in the population of fish. However with the death of so many dolphins, there was less prey for sharks to feed on, which meant a decrease in the shark population.
As you can see, water pollution greatly
affects food chains and food webs that are
connected to water. If one species is affected, it creates a chain reaction. That is why we must do our best to lessen the pollution of water, so we do not affect the ecosystems and the food chains. If one species is affected, the entire food chain is affected (U.S. Dept. Fish and Game, 2010).
Water pollution is a growing problem in our environments. Water pollution causes many problems and is very dangerous (Keep Earth Beautiful, 2002) For example let’s say a river is contaminated. The fish in the water and other living creatures then become infected with this substance and it may even kill them. If the fish or other living creatures die then that would mean less food for other animals such as birds. Then this could result in the population decrease of this species of bird. Then there would be two population decreases that would just throw off the whole food chain (Food Chains and Food Webs, 2001). When the birds die out from feasting on the contaminated fish then the bird’s population could decrease or possibly cease to exist. With a population decrease in the birds, the animals that prey on the birds would have a decrease in their resources which would possibly weaken their species. This could possibly consequence in the extinction of a species (Answers.com, 2011). Another threatening form of water pollution would be if the fish was infected by the contaminate and then when the bird ate it the bacteria or whatever it was would then spread to the bird and either kill it or continue to spread throughout the food chain.
This could be very bad for the environment and the ecosystem. Water pollution also affects other food chains and webs not just the system with fish, but if an animal comes to the water’s edge and begins to drink the contaminated water and become very sick or die (Marine Fisheries Food Webs, 2009). This could then cause the same chain reaction and make a lot of animals sick or contaminated. This again would most likely result in fluctuation of the ecosystems flow.