Which term describes a vessel constrained by draught?

A vessel constrained by draught is defined as a vessel that cannot navigate safely in the shallow waters due to its deeper hull that might run aground. This term specifically refers to the limitations imposed on a vessel's ability to maneuver effectively because its draft— the vertical distance between the waterline and the bottom of the hull (keel)— restricts movement in certain operational areas.

When a vessel is described as "restricted in her ability to maneuver," it indicates that there are physical limits on its steering and navigational capabilities, particularly when operating in shallow waters where the risk of grounding is high. This is crucial for ensuring safe navigation and preventing collisions, as it places the responsibility on other vessels to give way and navigate accordingly.

Other choices, such as being "operating under sail only" or "propelled by machinery only," focus on the propulsion method of the vessel rather than its maneuverability constraints. Similarly, being "engaged in fishing activities" pertains to the vessel's operational purpose and does not directly relate to the draught constraint. Thus, the key aspect of maneuverability limitation due to draught is best captured by the term "restricted in her ability to maneuver."