BURAS, La./Ho Chi Minh City (Reuters) – Savun Sim looked dejected as a large plastic vacuum hose sucked 2,600 pounds of wild Gulf of Mexico shrimp from his trawler’s ice hold. With dock prices at their lowest since 2009, pressured by a flood of cheap imports from shrimp farms across Asia, Sim said he would barely cover the cost of fuel for his two-day voyage at the far reaches of the Mississippi Delta. The Cambodian immigrant got 75 cents a pound for his mid-size shrimp — less than half of last year’s price — from the Ditcharo Seafood dock in Buras, Louisiana.