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and beach closures. Resuspension of sediments by propeller wash and 

 subsequent decline of light availability to eelgrass beds may be a 

 contributing factor for declines in some shallow bays. 



Dense accumulations of drift algae that often result from nutrient 

 loading contribute to eelgrass loss because drift material can smothers 

 young eelgrass seedlings an adult shoots (pers. obs.) and increases in 

 abundance of drift algae have been related to eelgrass losses elsewhere 

 (Hienhuis, 1983). Drift algae were not quantified in this study but it 

 is apparent from aerial photographs that this material has been 

 increasing in many bays during recent decades. Such changes in bottom 

 flora can be verified by analysis of core sections for changing 

 chlorophyll degradative products (Brush, 1984) and stable isotope ratios 

 (Fry et al., 1987), and should be studied. 



The loss of eelgrass from New Bedford Harbor could be due to any 

 number of causes including declining water quality, toxic pollutant 

 accumulation in the sediments (PCBs and heavy metals among others) , or 

 changes in hydrography resulting from the construction of hurricane 

 barriers there. No study of the effects of PCBs on eelgrass have been 

 undertaken, and no studies on long term changes of water quality have 

 been made in this area, therefore no conclusion can be made on the exact 

 causes of declines in New Bedford until further studies are conducted. 



There is no evidence for recent large scale declines of eelgrass 

 populations due to new outbreaks of the wasting disease as has been 

 reported elsewhere (Short et al., 1986). In two photograph sequences 

 (such as in Sippican Harbor during the early 1970's, Apponagansett Bay 

 during the early 1950's), isolated declines in eelgrass do not coincide 



