Both the United States and the Soviet Union trained marine mammals for military purposes during the Cold War, but a Swedish pioneer was decades ahead of them. It was in 1941, while the Second World War was raging all around Sweden, that the seal training facility at Gålö was built.
A Swedish behavioral scientist and psychologist named Valdemar Fellenius first saw the potential of using trained seals in the navy. Seals are excellent swimmers, can dive to great depths, and can stay under water for a long time. On top of this, they are very intelligent animals that are easy to train.
Pools for up to 50 seals were build in a desolate location on the Stockholm archipelago. The facility was built to look like piers and quays from a distance. The training began and the seals were taught to locate mines, submarines, and torpedoes that had missed their targets.
Unfortunately, the chief of staff at the navy headquarters wasn’t impressed with the results, even though Fellenius found the project to be successful. There were some technical difficulties getting the indicator buoys the seals would drop on targets to work properly, which could explain the skepticism. In September, 1943, it was decided that the facility should be closed and the program cancelled.
Fellenius really believed in his project and chose to keep it going without any compensation. But in April of 1945, when it seemed like the war would soon come to an end, the facility was shut down and the seals were moved to the open-air museum Skansen in Stockholm.
As an indication of how much ahead of his time Fallenius actually was, he soon got an offer from the United States to start a similar project using dolphins there. He did, however, turn down this offer.