As in the previous conflict the Government recognized that trawlers and fishermen had an essential role in the maintenance of Britain's sea lanes and the Admiralty was keen to get minesweeping operations underway. The Admiralty's appetite for trawlers remained considerable through out the war and altogether about 816 English and Welsh trawlers and in addition about 200 steam drifters were requisitioned at one time or another into the naval service.
The strength of English and Welsh trawler fleet actually available for fishing during the conflict was generally at about 25% of pre war levels, but in reality the catching power was much less. The Admiralty deliberately requisitioned most of the larger and more efficient modern vessels. Much of the North Sea-except for a strip down the east coast which varied in width between fifteen and thirty miles and on the inside of which was a mine belt- was closed to shipping.
Scarborough had 7 trawlers fishing in July 1939. This went down to 5 in December 1940, it was 4 in December 1942, 3 in December 1943 and 4 in December 1944. Hull had 191 at the beginning of the war but just 66 in December 1939. It went down to just 1 in December 1940. Grimsby had 381 at the start of the war and never went below 66 (December 1942). For both Hull and Grimsby numbers increased in 1943 and 1944.
The gradual westward movement of vessels made Fleetwood the premier British trawling port for a while. The principle grounds fished during the war were off Iceland, the Irish Sea, the west coast of Scotland and the Hebrides, as well as the north-west Ireland and off that country's south-western coasts. Fishing operations were also affected by enemy action; it was soon evident the Germans were again regarding fishing boats as legitimate targets. In the early months of the conflict a number of trawlers, particularly those working off the north and northwest coast of Ireland were sunk by gunfire from U-boats. The principal U-boat phase of the fishermans war lasted about three and a half months but towards the end of 1939 aircraft attacks increased in regularity.
Throughout the war mines remained the most deadly enemy. Sea mines sunk more fishing vessels than any other weapon. In Sept 1939 a programme of forming fishing fleets into sections of from four to eight vessels of which two were armed with twelve-pound guns, was introduced. In May 1940 those trawlers which had been fitted with guns were swiftly requisitioned and sent to help with the evacuation of Dunkirk and elsewhere. After the twelve-pounder trawlers were taken, various armaments were fitted including Lewis guns and other types of automatic weapons as well as kites, rockets and finally Oerlikon guns as they became available.
Fishermen also saved a lot of lives at sea, rescuing crews from stricken ships as well as British and enemy aircraft. When the first Schedule of Reserved Occupations was drawn up all classes of fishermen were reserved from the age of eighteen years, except for service in the navy. Though quite a number joined the Merchant Navy or the Royal Navy of their own accord, the policies that pursued throughout much of the Second World War meant that most fishermen continued fishing until required for naval service, and those recruited were usually used on small craft-particularly those of the Patrol Service-where their particular skills could be best deployed.
The war had a profound effect on the British fish supply. The total supply from all sources, fresh or frozen, amounted to 22,417,780 cwt in 1938 but by 1941 this had slumped to 7,771,016 or thirty-five percent of the 1938 total. There after there was a gradual improvement and by 1944 supplies were running at forty-eight percent of the pre-war total. The balance was made up by increased imports of demersal fish. These can be broadly split into direct landings by foreign fishing vessels and consignments arriving by cargo. Not surprisingly, given the shortfall in supplies and the rationing of many other food stuffs, fish, which remained unrationed, rose very sharply in price through 1940 and continued to rise until price controls were introduced in mid-1941. By that time Scottish cod was four times its pre-war price and scaith-a fish previously held in little regard-was worth up to ten times its pre-war value. It became widespread practice to head the fish at sea and land only their bodies, which increased the quantity landed out of a given catch weight compared with years when unheaded fish were landed.
The years 1940 and 1941 were probably the worst of the war for the British trawling trade. Working vessels were subject to intense enemy attack; indeed, nearly two thirds of the English and Welsh trawlers lost through enemy action whilst fishing over the six years of war went down in 1940 and 1941. Admiralty demands, in terms of requisitioning vessels and conscripting crews stripped the trade to the bone. Fishing on the North Sea grounds was particularly restricted and Hull, of course, was particularly badly affected.
Most trawlers and trawlermen drawn into the forces were directed into the Royal Naval Patrol Service. The Patrol Service has sometimes been described as a navy within the Royal Navy. Royal Naval Patrol Service vessels played a crucial role as minesweepers and losses to vessels and men throughout this activity remained high through out the war, many were fitted with asdic, an early form of sonar, and worked on anti submarine duties sending several U-boats to the bottom. Trawlers from the Patrol service saw action from all over the world. Within the return of peace it was evident that the Royal Naval Patrol Service had played a key role in the victory at sea and had paid a high price in consequence.
Although it is not possible to single out exactly how many fishermen died whilst serving with the Royal Navy it is known that some 2,385 officers and men of the Royal Naval Patrol Service, aged from sixteen to over sixty lost their lives. The Patrol Service lost nearly 500 vessels including more than 400 trawlers, drifters and whalers. These losses were far greater than any other branch of the Royal Navy. The fish trade as a whole and working fishermen in particular had also paid a heavy price. At least 1,243 British fishermen lost their lives whilst following their livelihood during the war. The effect can be gauged a little more accurately at certain ports: Hull boasted a fleet of 191 trawlers in July 1939 but by VE day ninety-six, just over half had been lost. Grimsby lost over 600 fishermen whilst or on naval service during the same period, The Lifeboatmen played an important part in wartime operations. The usual method of firing maroons was banned in April, 1940. It was December, 1944 before the ban was lifted.