sorting. Consequently, it was necessary to split several samples 

 from the 1987 survey (stations 3, 11, and 12). Care was taken to 

 maximize the accuracy of the final counts through the use of nested 

 sieves and the removal of organisms by "Ludox" flotation prior to 

 splitting the fine sieve fraction. However, splitting causes 

 uncertainty about the density and diversity of less abundant 

 species and requires increased time for sample preparation and 

 record keeping. These factors will have to be taken into account 

 in planning future studies at this site. The use of a smaller 

 sampler may be justified at stations where high densities of 

 organisms are found. Although most of the species examined in this 

 study are abundant in regional shelf habitats, a surprising number 

 have been renamed recently, are being re-examined, or have been 

 misidentif ied in older studies. These changes need to be 

 considered in the detailed comparison of the counts obtained here 

 with the previous surveys. 



Disposal of a large volume of dredged material from the 

 Providence River Improvement Project was carried out between late 

 1967 and early 1971 at the Brenton Reef site. Benthic 

 invertebrates were sampled at the disposal site on seven occasions 

 between 1970 and 1979. Five surveys carried out by the University 

 of Rhode Island are listed below. In each of these, 0.1 m 2 grab 

 samples were sieved to 0.75 mm. Additional samples were taken in 

 1978 and 1979 by the DAMOS program using 1 mm sieves. 



Number of 

 Stations 



Number of 

 Samples 



Report 



URI/COE September 1970 6 

 URI/COE December 1971 11 



17 Saila, Pratt, 



Polgar, 1972 

 33 Pratt, Saila, 

 Sissenwine, 1973 



URI/Sea 



Grant 

 URI/EPA 

 URI/EPA 

 DAMOS 



DAMOS 



December 1973 



Summer 1974 

 October 1975 

 April 1978 



Summer 1979 



11 



13 

 4 

 2 



44 



55 



12 



6 



10 



Annual Data 

 Report, May 1979 

 (NUSC, 1979) 

 Annual Report, 

 1980 

 (NUSC, 1980) 



The data obtained in the URI studies was difficult to 

 compare in detail with 1987 data because a different sieve size was 

 used, the data were not computerized, and some problems of 

 identification, sample dates, and locations were not resolved. 



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