The Chesapeake Bay is a complex ecosystem consisting of a flooded river delta. It is fed to the north by freshwater from the Susquehanna River and major rivers on Eastern and Western Shores of the Bay, which are mixed with water from the Atlantic Ocean. The diversity of aquatic and plant species is a characteristic of this Bay because its waters range from fresh, to saline, to ocean waters, combined with extensive warmth from the sun due to the shallow nature of the Bay. The Bay structure makes it possible for extensive systems of grasses to thrive such as salt marshes, wetlands, and several species of submerged grasses, which provide ample food and dissolved oxygen for fish, shellfish, and waterfowl. These grasses are extremely important for the …show more content…
Although the adult Bay anchovy tolerates temperatures ranging from 5-30o C, the larvae are more limited to optimal temperatures of 23-27o C. The most important threat to the Bay anchovy is the decrease in dissolved oxygen level caused by eutrophication, which is the main cause of hypoxia in coastal systems (Breitburg, 2002). As the water becomes hypoxic, there is less available habitat for Bay anchovy (Lee and Jones-Lee, 2005). This condition forces the fish to squeeze into less productive and narrow areas (Breitburg; Campbell and Rice, 2002,2014). Both adults and larvae require greater than 3.0 mg l-1 dissolved oxygen, leading to hypoxia - a condition that can eventually cause negative effects on the survival of eggs and larvae (Murphy and Stribling, 2015). In fact, Lee and Jones-Lee note that excessive nutrient load in the Bay has resulted caused the Pfiesteria problem and unprecedentedly high number of fish kills. While fish kills associated with toxic algal blooms have been recorded in other water bodies around the world, the rate of occurrence in Chesapeake has been extremely high over the past