Gales were experienced on the 4th, 5th, 6th, 7th, 9th and 10th. There was a great deal of mist and fog during the latter part of the month as well as a moderate amount of snow.
The enemy laid a large mine-field in the middle of the southern portion of the North Sea during April, thus pursuing the policy which it was expected he would adopt, regardless of the interests of neutrals. Fortunately, information as to its existence was obtained in time to prevent any of our ships from falling victims to the mines. But the mine-field was undoubtedly well placed strategically so as to interfere with the freedom of movement of our Fleet in southern waters if it were endeavouring to bring the High Sea Fleet to action, since it necessitated our ships making a wide detour to the eastward or westward to reach the waters to the southward of the mine-field; it was doubtless laid with this object in view.
In May the Grand Fleet flotillas were much occupied in endeavouring to locate and destroy enemy submarines, and the movements of the heavy ships were curtailed during the month owing to the absence of destroyers for the purpose of acting as a submarine screen.
The principal work of the destroyers in this connection—officers and men showing a fine spirit in carrying out what were frequently fruitless searches—was as follows:
May 1st–3rd.—The 2nd Flotilla was engaged in operations against enemy submarines reported, first, in the Fair Island Channel and, then, to the eastward and south-eastward of the Pentland Firth. The flotilla did not succeed in gaining touch with the submarines.
May 5th–7th.—One half of the 1st Flotilla was searching for a submarine off the Aberdeenshire coast, without result.
May 7th.—One division of the 2nd Flotilla was acting against a submarine reported in the Fair Island Channel, and then proceeded to work down the shipping route west of the Hebrides and Ireland in the hope of catching a submarine attacking trade.
May 8th.—Half the 4th Flotilla was searching for submarines off the east coast of the Orkneys.
May 10th–11th.—A division of the 4th Flotilla was searching for a submarine reported to be off North Ronaldshay; later, this division was reinforced by all available destroyers from Scapa, with orders that the force was to continue the search during the night, burning searchlights to assist the work and cause the submarine to submerge, thus exhausting her battery power.
May 13th.—Six destroyers were searching for a submarine reported west of Thurso.