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A shell disease that has plagued the southern New England lobster industry for years by making lobsters unsightly and in some cases unmarketable appears to be creeping northward to the lobster-rich grounds off the coast of Maine.
The number of lobsters suffering from shell disease remains tiny in Maine — only three out of every 1,000 lobsters sampled last year had the disease. But scientists and lobstermen are concerned because the prevalence grew fivefold from 2010 to 2012.
The disease, which is not harmful to humans, first became noticeable in southern New England waters in the 1990s. About one in every three or four lobsters caught in waters off southern Massachusetts and Rhode Island in recent years has been diseased.