Instinctive behavior occurs when an animal has a particular internal state while it is in the presence of a specific external stimulation called a releaser or a sign stimulus.
How many ships did the U-boats sink? During the war the U-boats sank about 2,779 ships for a total of 14.1 million tons GRT. This figure is roughly 70% of all allied shipping losses in all theatres of the war and to all hostile action. The most successful year was 1942 when over 6 million tons of shipping were sunk in the Atlantic.
Tactically, the battle was a draw. The final scorecard revealed that the British had lost 14 ships and 6,094 men while the Germans lost 11 ships and 2,551 men. Strategically, however, the British came out the winner as the Germans never again jeopardized their High Seas Fleet by allowing it to battle the British.