During World War I, Britain's position was not easy, including at sea. In this respect, the British were hardest hit by German submarines, which went on to the so-called "unlimited sea warfare". The and here ordinary seagulls, which had one extremely useful habit, came to the rescue of the British.
During the First World War, Germany was one of the leading countries in terms of the number of combat submarines. More importantly, the German fleet was perhaps the most effective in this area. With the escalation of the conflict on land, there was an aggravation of the conflict at sea. The more difficult the position of the German Empire became, the more desperate the battle was led by its fleet. Starting with pinpoint raider operations, when submarines attack only military targets, the Germans switched to unlimited naval war - they simply began to sink all ships of the Entente countries, including non-military ones.
By 1917, the situation at sea for the British was very difficult, despite the fact that Germany was clearly gradually weakening. The submarines of the Germans brought huge problems to both the combat and merchant fleets of the Entente. The only problem was that with the then development of technology, it was extremely problematic to detect submarines.
It is for this reason that the maritime department proposed a bold project for the use of gulls. The military suggested that the tendency of seagulls to sit on anything that protrudes from the water can play into their hands. The British hoped to be able to train birds to land on the raised periscopes of submarines. This was to facilitate the search and subsequent destruction of German submarines. Especially for this, many beaches of the United Kingdom were ordered to put carved out of wood periscopes, painted black. Surprisingly, the seagulls did land on them. True, it did not work to "train" the birds to search for submarines at sea.