Increased development around Waquoit Bay has resulted in increasing nitrogen loading over the past three decades. As a result, there has been an ecological shift from a system dominated by submerged aquatic vegetation to one dominated by macroalgae. Increases in phytoplankton blooms, decreased water clarity, an increasing number of episodes of hypoxia and anoxia resulting from increased oxygen demand, fish kills, and a collapse of scallop catch are other symptoms associated with the higher nitrogen levels. In areas of the bay where nitrogen input is low, grazers help keep macroalgae growth in check. But high loading triggers higher macroalgae growth rates and results in fewer grazers and lower grazing rates, and increased macroalgae canopies (Bricker et al. 2007).
Reference:
Bricker, S., B. Longstaff, W. Dennison, A. Jones, K. Boicourt, C. Wicks, and J. Woerner. 2007. Effects of Nutrient Enrichment In the Nation’s Estuaries: A Decade of Change. NOAA Coastal Ocean Program Decision Analysis Series No. 26. National Oceanic and Atmospheric Administration, National Centers for Coastal Ocean Science, Silver Spring, MD. Accessed October 2016. https://yosemite.epa.gov/oa/EAB_Web_Docket.nsf/(Filings)/3BE82A42C7ED8C3585257B120059CB8A/$File/Opposition%20to%20Petition%20for%20Review%20–%20Ex.%2010%20Part1…23.53.pdf.