On a busy Thursday afternoon, people stood in line to buy shrimp at Rose's Seafood, a no-frills market on a little waterfront street in Kemah. What wasn't as obvious is that roughly half the shrimp spread out before them in big, wet piles were imported — although the market is located a stone's throw from where shrimp boats dock. Shrimp producers from countries like China and Vietnam,plus four others, are facing the distinct possibility of paying substantial duties as the result of an anti-dumping petition working its way through Washington. The first indications of how big the duties will be...