Wrecks over 100 years old and archaeological objects found underwater are protected under the National Monuments (Amendment) Acts 1987 and 1994. Significant wrecks less that 100 years old can be designated by Underwater Heritage Order (UHO) on account of their historical, archaeological or artistic importance as is the case with the wreck of the RMS Lusitania lost off the Old Head of Kinsale in 1915. UHOs can also be used to designate areas of seabed or land covered by water to more clearly define and protect wreck sites and archaeological objects . https://www.archaeology.ie/underwater-archaeology
In July, 1917, USS Walke arrived in Queenstown (now Cobh) in Ireland. Queenstown was the centre for anti-submarine forces, on the Western Approaches, under the command of Admiral Lewis Bayley, Commander in Chief , Coast of Ireland.
Initially there was uncertainty as to the most effective use of destroyers. At first they were given patrol areas which they would scout, singly or in pairs. Any stray incoming merchantmen seen, were to be escorted to near their destinations. This was a most ineffective use of the force, as the chances of coming across, and destroying a lone submarine in the vastness of the Western Approaches was virtually nil.
By Summer 1917, under the urging of commanders such as Admiral Sims, Commander of US Naval Forces in Europe, the convoy system was initiated. Groups of merchantmen were escorted through the war zone by flanking destroyer screens. This had the dual effect of reducing the amount of targets for German u-boats, and allowing destroyers and sloops to attack the harassing submarines. The priorities of the destroyers were to:
Protect and escort Merchantmen.
Save the crews and passengers of torpedoed ships.
Anti-submarine patrols did continue also for the duration of the war, especially in the Irish Sea and close to the coast of France, where u-boats would try to sink merchantmen as the convoys dispersed. In 1918, any destroyer in the Irish Sea, which was not actively convoying, came under the orders of The Irish Sea Hunting Flotilla, under the command of Captain Gordon Campbell VC based in Holyhead, Wales. US destroyers were also used to patrol the west coast of Ireland to hunt suspected gun-running ships, for Irish Republicans.
The destroyers , initially, were ill-equipped to fight submerged submarines. When they arrived in Europe they were armed with guns and torpedoes. The only undersea weapons supplied were single hand-launched 50lb depth charges which were particularly ineffective. It was the later fitting of dual depth charge racks on the sterns of the ships, Thornycroft depth charge throwers, and Y shaped charge throwers that turned them into a dangerous force.
These were capable of dropping and firing a continuous patterned barrage of 200lb, charges around a submarine's suspected position. Most of the retro-fitting of these armaments was done at Cammel Laird in Birkenhead, England.
On the 21st of July, 1917, USS Walke was on anti-submarine patrol. An object was spotted emerging from the water, in position 50.36N, 12.10W, and was thought to be a periscope. Walke sped to the attack and opened fire. 19 shots were fired in all. The object splintered, and was thought to be the mast of a sunken ship. Walke dropped depth charge and circled to see effect. Brown staining rose on the water. No oil slick was observed.
On the 17th of November, 1917, USS Walke left the Queenstown Command, and returned to the USA.