John S Dempster Jr. is sister to Shearwater and Reedville, see those vessels for details, links in the sidebar. All three vessels were originally small Army transports, converted to Menhaden fishing by Omega Protein company. FS-355 was USCG-manned, and retained by USA as PVT Carl V. Sheridan (see below) until sold in 1972.
The aging Shearwater and Reedville were retired when Omega got two new modern vessels in 2017, but Dempster was kept as a reserve. Finally, almost 80 years old, the Dempster was sent to her reward as well. Another sister, Tangier Island, was reefed off Georgia in 2020. As of 2023, one old sister remains - Smuggler's Point, FS-400, launched in 1944!
The Coast Guard classification for this type was BUSL, for 'boat utility stern loading'. These boats had facilities to maintain the crew for 48 hours. They were powered by a diesel engine driving a steerable propeller, which would have made them extremely maneuverable. They were replaced by a 49-foot model.