The U.S. Court of Appeals
for the Eleventh Circuit ruled that a vessel tied off to a mooring buoy is anchored, rather than moored. In the instant case, defendant's barge was tied off to a mooring buoy outside the regular navigation channel. The barge was not lit at night, nor was it sounding fog signals. Plaintiff's shrimp boat got off course at night in the fog and allided with the barge. Defendant contended that it did not contribute to the allision. The court held that, since the barge was anchored, rather than moored, and was not lit and was not sounding signals, that it was in violation of the navigation rules. Sunderland Marine Mutual Insurance Co., Ltd. v. Weeks Marine Construction Co.
Source: HK Law