Uzan Maru was a cargo ship of 5,014 tons. The characters are 宇山丸. Japanese records list her as a captured ship, owned by Kokoku Sangyo. She was a merchant, not a navy auxiliary. Her builder, and the name she carried before she was taken, are not known.
On 2 May 1942 she was off Kashinozaki, the light at the southern end of Kii Oshima, at 33°26′N, 135°52′E. Trout sank her there. Frank W. Fenno had the submarine.
The postwar assessment counts her for that patrol. She went down on 2 May.