The shipping industry continues to watch nervously as the International Longshoremen’s Association and United States Maritime Alliance continue contract negotiations that started last March. The ILA and USMX agreed in late December to a second contract extension, through Feb. 6. The extension averted a threatened East and Gulf Coast port strike on Dec. 30. The latest extension followed a tentative agreement on container royalties that cleared the way for discussion of the equally contentious issue of work rules and productivity.