A total of 5, 933 individuals comprising 224 species were 

 collected. The dominant taxa were polychaete annelids and bivalve 

 mollusks. Generally enhanced productivities were evident at the borrow 

 stations throughout the year, with borrow station 3 consistently 

 containing more species and individuals than the control stations. 

 Species diversities were usually higher at the borrow stations than at 

 the control stations, with the single exception due to a high 

 concentration of the bivalve £", nitens at borrow station 4 in June. 



Although the faunal similarity analysis indicated that a 

 qualitative change in the fauna of the borrow area had occurred, this 

 change was not considered detrimental. Conspicuous patterns of 

 heterogeneous distribution of fauna were evident in this study, 

 particularly with the bivalve E. nitens. Pronounced seasonal 

 fluctuations in species composition and abundance were noted at each 

 station. 



It is concluded that the offshore dredging operations conducted in 

 1972 off Hillsboro Beach, Florida, caused no observable adverse effects, 

 in terms of reduced numbers of species, reduced faunal abundance, or 

 reduced species diversity within the borrow area. 



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