[2] Considered “strongly built” and a “good sea boat” for potential employment as a minesweeper, Mariner was delivered to the Navy on 25 September 1917.

Following that period of local work, she got underway on 6 February 1918 in company with converted yachts Yacona and Wadena, bound for New London, Connecticut.

She briefly towed the submarine chaser SC-177 before the tug herself began to founder in the heavy southwesterly gale that sprang up on 26 February.

Her seams opened to the sea by the pounding of the waves, her pumps failed; rising water doused the fires under her boilers and rendered her helpless.

[1] While the rest of the convoy continued on its passage, Wadena retrieved SC-177 and ultimately reached the British naval station at Hamilton, Bermuda, on 1 March 1918.