A grey cat walks along a street a light behind it.

Which animal is a better spy—a pigeon or a cat? We actually know the answer.

The CIA spent $20 million on an eavesdropping cat, but it’s the humble pigeon that’s pulled off the greatest intelligence heists.

Most people don't think twice when they see a cat, which makes it ideal for under-the-radar espionage. In the 1960s, the CIA sank millions into Operation Acoustic Kitty to create the world's first feline espionage cyborg. 
Photograph By VINCENT J. MUSI
ByChristian Elliott
February 13, 2024

Amid the high stakes and desperation of the Cold War, the U.S. Central Intelligence Agency faced a perpetual espionage challenge: access. Every situation called for its own unique solution. How do you get a spy inside the secure inner sanctum of a foreign head of state, for example, who only admits his closest confidants and the stray cats he has a fondness for? You send in a feline spy equipped with a hidden listening device, of course.

The CIA called the operation Acoustic Kitty. But after five years and likely millions of dollars in research and development, the project was scrapped in 1967, for reasons any cat owner might have anticipated—it’s not easy to convince a cat, of all animals, to go exactly where it’s directed and stay within range of a radio receiver.

Before digital technology and microelectronics, spying was hard, and everything was on the table. Throughout the 20th century, “intelligence services worldwide looked at animals as a possible way of both clandestinely getting into locations that an individual wouldn't otherwise have access to, and for carrying messages or equipment,” says Robert Wallace, who directed the CIA’s Office of Technical Service, the branch responsible for spy gadgets, in the 1990s. “You look at all the alternatives and if one looks viable, you’re gonna pursue it, until either you prove that you can’t do it, or a better way comes along.”

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As outlandish as it may sound today, the CIA was quite serious about Operation Acoustic Kitty. And it was just one of many efforts to recruit animal secret agents for their sensory capabilities and ability to blend in–with varying degrees of success. But what makes an animal a good spy candidate? And do furry and feathery secret agents still have a role to play in espionage today?

Curiosity kills the cat?

Acoustic Kitty was a feline cyborg—a blend of unassuming household pet and high-tech. In a minor surgery, a veterinarian inserted a small microphone inside its pointy ear–an excellent natural funnel for directing sound. Then, they wired the microphone to a battery pack under the cat’s loose skin, connected to an external antenna woven through the cat’s long fur.

The surgery itself was pretty revolutionary, Wallace says. “This was before pacemakers, we weren’t putting electronics into mammals, because it’s a very inhospitable environment–it’s humid, it’s warm, it’s wet.” The cat was just fine, he recalls, although the project manager fainted at the sight of blood. And the technology worked–the cat bug could pick up and transmit conversations. But there was a problem–despite its CIA training, Acoustic Kitty had a mind of its own and wasn’t great at staying near its targets. A field test in a public park, likely full of distractions like pigeons and squirrels, proved Acoustic Kitty wasn’t going to work out.

“You kind of wonder what they were thinking,” says David Welker, a CIA agency historian. “Did nobody own a cat? You can't make a cat do anything. As a proud cat owner, I could have told them that wouldn’t work.”

Innate curiosity may seem like a good trait for espionage, but it’s also known to kill the cat. In a popular account by Victor Marchetti, a former CIA officer and critic of the agency, that’s exactly how the story ends. On Acoustic Kitty’s first mission—that field test in a park—the cat spy wandered across a street and was promptly run over by a taxi.

“Marchetti’s version is a lot more fun,” said Wallace, but in reality, the cat lived a normal life after the spy gear was removed. That’s the official CIA position too, according to Welker.

A pigeon is photographed with a a camera on its body.
The first pigeon camera, created by German inventor Julius Neubronner in 1907, involved a lightweight aluminum harness and time-delay camera. 
Photograph By Rorhof/ Stadtarchiv Kronberg

Spies of a feather flock together

To find a more promising animal secret agent candidate, the CIA needed look no further than Acoustic Kitty’s natural enemy: birds. Specifically, the humble pigeon. Warring armies have relied on homing pigeons as messengers since ancient times, but the birds came into their own as espionage assets in World War II.

At the beginning of the war, British intelligence networks had been shattered by the fast German advance. Aerial reconnaissance was nonexistent in occupied Europe, and the Nazi’s notorious Enigma code hadn’t yet been decrypted. But in Britain’s darkest hour, First World War veterans who’d used pigeons to communicate across the trenches stepped up with a radical idea.

“They decide they’ll drop them from RAF planes,” says Gordon Corera, a British security journalist and author of Operation Columba: The Secret Pigeon Service. On secret flights over occupied Europe, “They push out these canisters of pigeons with a parachute attached, drop them and see if they get anything back.”

Villagers in France and Belgium, desperate to resist Nazi occupation, risked their lives by writing messages on tiny slips of paper and attaching them to the legs of confused British pigeons that landed in boxes in their gardens and fields.

“The crucial thing about pigeons is they have this superpower, the ability to find their way home,” says Corera. “It’s still not entirely understood how they manage to, even if you drop them hundreds of miles away in a place they’ve never been before.”

Operation Columba was a huge success—despite significant losses, spy pigeons carried some 1,000 messages back to London with information on radar installations, Nazi troop movements, and V1 rocket sites. The pigeons won medals for their bravery.

But World War II wasn’t the end for spy pigeons. During the Cold War, British intelligence tested the bird’s ability to fly through plumes of radioactive material, to send messages in a nuclear war. And in the U.S., in the 1970s, in what became known as Operation Tacana, the CIA designed a tiny, pigeon-sized film camera the birds could carry over Soviet military facilities–taking higher resolution photos than contemporary spy satellites–on their way home after being released from a trapdoor in the floor of a modified car.

The CIA tried to train more exotic bird spies, like falcons, ravens, even cockatoos, to carry the camera, but in the end settled again on the humble pigeon for its ability to hide in plain sight, fly great distances without landing, and always find its way home.

“Pigeons just don’t attract any attention, says Welker, the CIA historian. “They’re everywhere, and so nobody thinks oddly of a pigeon flying overhead.”

Marshaling an undercover menagerie

Today, technologies like drones are more likely to provide those critical non-human perspectives than cats or pigeons, so Acoustic Kitty and Project Tacana have settled into the realm of CIA history and myth. “What happened in the technical surveillance world is better ways came along very quickly in the ‘80s,” notes Wallace. “Sometimes things get obsolete very, very quickly.”

But that doesn’t mean the CIA has left animals fully in the past. “Times change, technologies change, but what hasn’t changed is the CIA’s mission of providing the best possible intelligence,” says Welker. “Animals, they’re always a potential partner in our CIA mission.”

To Corera, the security journalist who’s watched India and Pakistan trade accusations about spy pigeons and heard rumors of a Chinese pigeon training branch, there’s an obvious reason why. “As we become more reliant on technology, we also understand we can become over reliant and overdependent on technology,” he says. When it fails, spy agencies need backup options. “And amongst those might be pigeons. So, I think the era of the pigeon is not necessarily over.”

Cats might be another matter.

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