American Shad
Effect of Pollution in the Chesapeake Bay on this species
Too many nutrients in the water, like Phosphorus and Nitrogen, cause a large build-up of algae in the water. This blocks out the sunlight making it hard for the fish to get sun. The excess of this pollution is caused by lack of plants along the edge which would normally soak up the extra nutrients. Another contributing factor is the large amounts of concrete surrounding the bay which cause the pollutants to run right off into the Bay.
Also many other objects that are deposited in to the Bay can be damaging to the fish if swallowed or entangled in.