Seaman Craig Nelson, a crewmember aboard the Coast Guard Cutter Bluebell, ties a knot in the line of a tag-line used to keep control of a buoy before it is placed into the Columbia River, Oct. 30, 2018.
Effective seamanship skills, like quickly tying knots, is a requirement of all Coast Guard cutter members and aids to navigation workers.
U.S. Coast Guard photo by Petty Officer 3rd Class Trevor Lilburn.