Martha the passenger pigeon

September 1 is an anniversary with a sad distinction. When Martha the passenger pigeon died at the Cincinnati Zoo 100 years ago, it was one of the few times that the extinction of a species could be pinpointed to a precise day.

There are many lessons in the story of the passenger pigeon, but perhaps the most sobering one is how the species went so quickly from almost unimaginable abundance to nothing.

"A message that people who love animals should take away is that even if something is common, unless we’re good stewards, we can lose it," says Joel Greenberg, author of A Feathered River Across the Sky: the Passenger Pigeon’s Flight to Extinction.

When Birds Blocked the Sun

At one time, the passenger pigeon was the most numerous bird in its native eastern North America. It was not closely related to the rock pigeon that spread with European colonization and lives throughout the cities of the world, nor to the familiar species it most closely resembles. Greenberg says that it looked like "a mourning dove on steroids" — about a third larger and more brightly colored. And what made it most noticeably different was its habit of congregating in huge numbers during migration and breeding seasons. 

"John James Audubon, America’s best-known student of birds, lived in Henderson, Kentucky, for a while," he says, "and made a trip to Louisville over the course of three days. He said the birds eclipsed the sun for the duration."

Audubon’s story was far from unique. Greenberg says there are numerous records of the huge flights: "For 300 years, people writing in five or six different languages that I am aware of described periods where over major cities — Chicago, Philadelphia, New York, St. Louis, Columbus — the sky would be dark for hours at a time."

So it’s all the more shocking how quickly the species disappeared. Scholars have concluded from a written description that a flock near Toronto may have exceeded 2 billion birds in the 1860s. And then, Greenberg says, "Forty years later, in the spring of 1902 in Laurel, Indiana, the last wild bird was shot that we know of with certainty."

Their Path to Extinction

How did it happen? The large numbers of birds in one place could be a nuisance, and farmers did sometimes kill them to protect crops, but the real problem was that they were hunted commercially for food — helped along by modern technology. 

"What really drove them to extinction was they became a commodity," Greenberg says. "With the expansion of the railroad, wherever birds were killed, they could be sent to the burgeoning markets of the Midwest and East." And the telegraph allowed people who saw the pigeons to disseminate their location widely and quickly. These innovations created an industry: hunters whose business was following the birds from place to place all year long.

Habitat loss probably also played a role in making the birds easier to find, since there were fewer places for them to nest. And because they bred slowly, their numbers couldn’t keep up. "They nested once a year and produced one egg at best," he says. "And birds were being killed on the nesting grounds, so they were so harassed that they’d abandon the nest."

Audubon print of passenger pigeons

Decline and Denial

Greenberg says that hunters noticed things were changing by the late 1870s, but it was easy to make excuses. "When confronted with an inconvenient truth, one way people deal with it is to deny it," he says.

In 1882, a couple of areas still had large nestings. One in Wisconsin had a million birds — enough to lead people to think that there were plenty of passenger pigeons left. But Greenberg explains that this was a fraction of what the numbers had been, and it was the last time the birds congregated in anywhere near those numbers.

When hunters did suspect the bird was disappearing, they reacted in a way that made matters worse.

"Hunters could have done one of two things. One was: ‘We want to keep this occupation, [so] let’s lay off killing the birds,’" Greenberg says. "They did the other thing: ‘This is a source of revenue; we’re going to get every last penny we can.’"

The Last Flocks

After the last known wild pigeon was killed, there were still three captive flocks, two owned by researchers and one at the Cincinnati Zoo. It’s not clear from historical records where Martha was born or exactly how old she was, but Greenberg says the best evidence shows that she was born in captivity and at some point was sent from one of the researcher’s flocks to the zoo.

"She never knew flight in life — the only migrating she ever did was by train," he explains. The researcher taught in Chicago and was the director of a lab in Massachusetts. "When school let out in June, he’d load his pigeons up and go to Massachusetts," Greenberg says.

The second-to-last pigeon, named George, died on July 10, 1910, leaving Martha as the last of her kind. She became a big attraction, which wasn’t necessarily a good thing. "There are reports that crowds on the weekends would throw sand at her to get her to move," Greenberg says.

Keepers cordoned off Martha’s cage so people couldn’t get close, and as the bird got older and had difficulty moving, they lowered her perch to make it easier for her to get onto it. Finally on September 1, 1914, she was found dead in her cage.

As had been arranged, she was sent to Washington, D.C., where she was preserved. She has been at the Smithsonian ever since — leaving only twice for special occasions: once for a golden jubilee at the Zoological Society of San Diego and once when a building was dedicated in her honor at the Cincinnati Zoo. Both times, she was flown first class.

No Last-minute Rescue

From a modern perspective, it’s hard to imagine how the extinction happened. As numbers decreased, why weren’t laws passed to protect the pigeons? Why weren’t captive birds bred to save the species?

But these were very different times, long before the Endangered Species Act and long before zoos routinely bred animals even for exhibition purposes — most were collected from the wild. The idea of breeding to prevent extinction hadn’t yet arisen, and even if someone had had the inspiration, successful captive breeding requires knowledge about the animal’s natural behavior. But the species hadn’t been studied in the wild — most people who observed them had a very different priority. "When someone had the opportunity to be close to a passenger pigeon in the wild, in virtually every instance, they killed it," Greenberg says.

The concept of wildlife protection legislation was in its infancy at the time. Starting in the 1850s, states had begun to pass laws protecting songbirds and some game birds. But the pigeons slipped through the cracks, and the one real chance they had didn’t work out: In 1857, Ohio studied whether to include them in a bird protection law and concluded that they were so abundant that they didn’t need protection. It was later deemed the fifth most embarrassing moment in state history by the Ohio Historical Society.

Michigan was the only state that ever banned the killing of passenger pigeons — in 1897, according to Greenberg. "That’s the good news," he says. "The bad news: By then, there were none left."

A Lasting Legacy

The only comfort from the tale of the passenger pigeon is that it did make people take notice at a time when the idea of conservation was just beginning to take hold, and the world really did change as a result. "I think in good conscience, you can trace the conservation laws we have now to the shocking loss of the pigeon," Greengerg says. "People remembered it, and they behaved differently afterward."

Greenberg says that the extinction of the passenger pigeon helped inspire the nation’s first conservation movement, out of which came the Lacey Act, the first federal bird protection law, and the Migratory Bird Treaty Act. John F. Lacey, a Republican congressman from Iowa, talked about the passenger pigeon as he argued for the law that was named after him. "Lacey got up on the floor of the House and said, ‘It’s too late for the pigeon, but there’s still good work to be done,’" Greenberg says.

This set the stage for the movements later in the 20th century that led to additional legislation protecting the environment and endangered species.

"If you end the story on September 1, 1914, you could say it’s a sad story, but it didn’t end there," Greenberg says. "It changed the way we as a country deal with wildlife."

To learn more about Joel Greenberg and his efforts to keep the passenger pigeon’s loss front of mind, visit

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