A wetlands would be your fast food joint. Wildlife that eats submerged vegetation depend on wetlands. Many birds depend on wetlands as they migrate, following food sources and travelling to breeding sites.
Wetlands are like gas stations for migratory birds.
Amphibians, such as frogs and toads, depend on wetlands for survival. They live half in the water and half on land - so they need to live on the edge of water. When wetlands are polluted, amphibians suffer. They breathe through their skin. When water is polluted, the chemicals soak through their skin, causing deformities and extinction.