Based on the Coast Guard Historian’s timeline, https://www.history.uscg.mil/research/chronology/
With inspiration from Mike Kelso

March 15

US AMP (Army Mine Planter) GEN. JOHN P. STORY was built in 1919 for the Army Corps of Engineers, and was transferred to the USLHS in 1922 and renamed USLHT ACACIA (pic.5). With twin screws, a length-over-all of 172 ½ ft., she displaced 1130 tons. She was further renamed USCGC ACACIA (WAGL 200) after the USLHS was merged into the USCG on September 1, 1939. Also as part of the merger, the 9th LHD became part of the 7th CG District. The unarmed ACACIA was the only buoy tender sunk by a U-boat during WWII, on March 15, 1942.

1942  The 172-foot tender CGC Acacia was en route from Curacao, Netherlands West Indies to Antigua, British West Indies, when she was sunk by shellfire from the German submarine U-161.  The entire crew of Acacia was rescued.  She was the only Coast Guard buoy tender sunk by enemy action during the war.

Map of Manus and Los Negros during World War II. Source: Building the Navy’s Bases in World War II, Volume II.

1944  Coast Guardsmen participated in the invasions of Manus in the Admiralties and Emirau (St. Mathias Islands).

PB-1G, CG-77249, on runway in Argentia, Newfoundland, running up engines, International Ice Patrol, 15 February 1954. Photo No. 021554-01. Original caption states: “U.S. Coast Guard plane, PB-1G (B-17), taking off on a 9-hour patrol.”

1946  For the first time, Coast Guard aircraft supplemented the work of the Coast Guard patrol vessels of the International Ice Patrol, scouting for ice and determining the limits of the ice fields from the air.

1983  The Coast Guard retired its last HC-131A Samaritan.

1991  F/V Alaskan Monarch became trapped in the ice-encrusted Bering Sea near St. Paul, Alaska and was in danger of being swept onto the breakwater rocks outside St. Paul Harbor.  CGC Storis and an HH-3 from AIRSTA Kodiak, under the command of LT Laura H. Guth, responded.  After a flight of 600 miles, including a winter crossing of the Alaska Peninsula and 400 miles of open water, Guth and her crew rescued four of the six-man crew before waves crashed over the vessel and swept the two remaining crewmen into the frigid water.  They both were quickly pulled from the water safely.

1997  Operation Gulf Shield began. This operation was a counterpart to the counter-narcotics Operation Frontier Shield.