China was so hungry for Maine lobster last summer that Stephanie Nadeau, a live lobster dealer from Arundel, was selling $100,000 of lobster to Beijing, Guangzhou and Shanghai on a good day. She was living and breathing the China lobster market, which after seven years of 1 a.m. sales calls and repeated trips to the mainland had grown to account for a third of her annual sales. The lobster pipeline from Maine to China shut down on July 5, however, when China hit U.S.