° Are any effects of sludge dumping detectable in 



sediments at the 106 Mile Site and nearby areas as 

 shown by the isolation of microbiological agents 

 (viruses, bacteria, fungi, protozoans, etc.) ? 



Studies on microbial agents in deepwater sediments 

 at the site should be undertaken. Investigations of this nature 

 are required to provide definitive answers. 



° Do microorganisms that cause shell disease differ 

 geographically or by crustacean host species ? 



Several species of the bacterial genus Vibrio have 

 been identified from shell disease lesions of shrimp, crabs, and 

 lobsters and appear to be universally associated with this 

 disease. Other types of bacteria and fungi have been reported 

 from crustaceans but no attempts have been made to determine 

 whether each type of organism can cause disease in more than one 

 species of crustacean. Studies on geographical differences 

 should be done. 



° Is there a relationship between contaminants in 

 tissues and shell disease ? 



There are no data currently available to answer 

 this question. 



° Is shell disease a naturally occurring condition 

 or is it related to pollution ? 



Shell disease is caused by bacteria or fungi as a 

 naturally occurring disease in crustaceans. Laboratory studies 

 have shown, however, that crowding in cages, pens, etc. may 

 increase the severity and prevalence of the disease. Trawl 

 surveys and commercial catches have shown that high prevalences 

 (>15%) occur in polluted or degraded habitats. 



° Is there any evidence to support claims by 

 commercial fishermen that there is a recent 

 increase in shell disease, and a decrease in 

 catches? 



Whereas there have been no scientific studies or 

 surveys in the past few years that enable the Working Group to 

 confirm or deny these reports from commercial fishermen, there is 

 general agreement among fishermen from Ocean City, Maryland, New 

 Jersey, New York, Connecticut, Massachusetts, and Rhode Island, 

 that shell disease affects the marketability of crabs and 

 lobsters because of unsightly blackened lesions (effects being 

 most noticeable in the last five years) . Although the Working 

 Group cannot address increases or decreases in individual 

 catches, available data indicate that the total landings for 

 lobsters have increased during the last decade. 



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