Official caption: “Five steward’s mates stand at their battle stations, as a gun crew aboard a Coast Guard-manned frigate in the southwest Pacific.”
Note the gunner is missing his left shoe but doesn’t seem that affected by it, as there is a pile of 20mm brass in the gun tub. NARA 26-G-3797 https://catalog.archives.gov/id/513214
“On call to general quarters, these Coast Guardsmen man a 20mm AA gun. They are, left to right, James L. Wesley, standing with a clip of shells; L. S. Haywood, firing; William Watson, reporting to bridge by phone from his gun captain’s post; William Morton, loading a full clip, assisted by Odis Lane, facing camera across gun barrel.”
Besides their own vessels, the Coast Guard manned a myriad of ships on the Navy List to include LSTs, LCIs, and transports. Notably, of the 96 Tacoma-class patrol frigates built during the war, the USCG ran 75 (the balance had gone as Lend-Lease to Russia and Britain). Of those 75, most were detailed to convoy duty in the Atlantic but 18 that were built on the West Coast were dispatched in a squadron to the Pacific where they gave a good account of themselves in ASW patrols, landing Rangers and Marines on isolated atolls, and providing NGFS for invasion forces throughout the Philippine littoral.