White Russian Spy?

In the late 19th century, European militaries had come to appreciate that thoroughly-trained and well-handled dogs could perform useful military services, such as finding wounded soldiers on the battlefield and guarding military installations and outposts. Over the course of the 20th century, new roles were found for them: notably, detecting mines and explosives during World War II.

Given the success achieved with dogs, it was perhaps inevitable that experiments would begin with other intelligent and trainable animals, including marine mammals. The earliest of these experiments took place during World War I, when Britain’s Royal Navy unsuccessfully attempted to train sea lions to locate German submarines.

The early training – conducted at a facility on Lake Bala in Gwynedd, Wales – went well. But once the sea lions were released into the open sea, they were generally found to be more interested in pursuing shoals of fish than U-boats – much to the frustration of the officers involved.

.....

In coldly scientific language – and with little acknowledgement of the sophisticated intelligence and capacity for emotion expressed by these animals – one American manufacturer of military sonar equipment described them as:

Self-propelled marine vehicle[s], or platform[s]; with a built-in sonar sensor system suitable for detecting and classifying targets; and carrying an on-board computer … capable of being programmed for complex performance.

https://theconversation.com/russian-spy-whale-the-disturbing-history-of-military-marine-mammals-116305 .