German Minefields and Minesweeping Operations in the North Sea and Beyond

In early spring 1915, there were about 238 minesweeping vessels in service in the seas around the British Isles. Except for some gunboats and hired paddle steamers, the majority of these were fishing vessels, at that time trawlers, their crews mainly fishermen, and their domestic sphere of operations still primarily focused on the east coast of England. Although there were about 63 minesweepers sailing out of Scottish ports, many providing protection for the Grand Fleet and other Royal Navy surface ships, and a total of around 34 craft covering the western ports or the English Channel eastwards to Portsmouth, most of the remainder were based at key eastern ports from North Shields down to Dover (Table 1).

Whilst other vessels had already been despatched for minesweeping work off the Dardanelles, the disposition of these flotillas of fishermen and hired fishing vessels reflected the main areas of German minelaying off the coasts of Britain in the first year of the war. Significant operations had recently taken place off the eastern side of the Dogger Bank and further substantial activities were soon undertaken. Presumably, such offshore minefields were primarily targeted at heavy Royal Navy warships sweeping through the North Sea or engaged in chasing German warships towards Heligoland and the like. Further minelaying operations, directly involving the cruiser Hamburg supported by various other vessels including battle cruisers, were carried out around 18 May. Whilst these were under way, four British civilian fishing trawlers working in the North Sea – the King Charles of Grimsby and the Euclid, Duke of Wellington, and Titania from Hull – were captured and then sunk by German torpedo boats; their crews taken back to Germany as prisoners, presumably to keep the minelaying operations secret. Before the end of the month these trawlermen had been incarcerated in Ruhleben internment camp just outside of Berlin.

Typically, these minefields were often discovered in tragic fashion, although not usually by large warships: the fishing vessels Angelo and Sabrina, owned by Hellyers of Hull, for example, probably foundered on mines laid off the Dogger Bank on 21 May, just three days after the Hamburg's lethal voyage. The following month the steam trawler Dovey was lost on yet another such field, this one laid some 50 miles east by south of Spurn Head.