The CIA has declassified details of its operations with pigeons during the Cold War. The document was studied by the BBC correspondent.
Pigeons were trained for secret missions related to photographing objects on the territory of the USSR. In the 1970s, during Operation Takana, intelligence agencies studied the possibility of fixing small cameras that automatically take pictures on birds. It turned out that such photographs were better than satellite ones.
By 1967, the CIA spent more than $ 600,000 on programs involving birds, dolphins, dogs, and cats. Pigeons were best suited for espionage missions because they could find their way home. They tried to place eavesdroppers in cats, and experimented with searching for traces of radioactive or biological weapons over dolphins.