From the November 2013 issue of Smithsonian Magazine:
Passenger Pigeon
1914 National History Museum
The wilderness was no match for the American capacity to destroy it
Once, passenger pigeons filled the skies-"an almost inconceivable multitude" wrote an ornithologist who in the early 1800s calculated that a Kentucky flock held more than two billion. Then houses replaced habitats, and people killed the birds en masse, baking them in pigeon pies. The Cincinnati Zoo, where Martha spent her life, offered a $1,000 reward for a mate, but she died alone, in 1914, and was shipped on ice to the Smithsonian, the last of her species. But new hope is on the wing: Geneticists say they might be able to bring the passenger pigeon back in a feat of "de-extinction."
Martha, the World’s Last Passenger Pigeon
By Joseph Stromberg - National Museum of Natural History, Nature
September 01, 2011 | 8:05 AM PDT
Martha, the last surviving member of the passenger pigeon species. Photo courtesy Natural History Museum
In 1813, ornithologist John James Audubon was riding across the state of Kentucky when the sky was darkened by an enormous flock of passenger pigeons. The cloud of birds continued past all day. He estimatedthat there were as many as 1 billion pigeons in the flock; other scientists have calculated that the species once constituted 25 to 40 percent of all birds in the U.S.
Just over a century later, on September 1, 1914 at 1 p.m., Martha, the world’s last passenger pigeon, died at the Cincinnati Zoo. For the last 97 years, her body has been at Smithsonian’s Museum of Natural History, a reminder of the fragility of natural ecosystems and the looming threat of species extinction.
“Before the 1840s, they were one of the most numerous species of birds in North America,” says James Dean, collections manager in the division of birds at the museum. “They occurred over much of the United States, from the central plains all the way over to the east.” About twice the size of common pigeons, they ate mostly seeds and nuts, and typically lived in giant, dense flocks with a tight-knit social structure.
But over the latter half of the 19th century, their numbers dropped steadily. “By the 1870s and 80s, they were really starting to decline,” Dean says. “A species like this, once their populations start declining far enough, they’re just not able to sustain the colonies. They don’t reproduce enough, and the flocks get smaller and smaller.”
The initial cause was the cutting down of forests to build houses and clear farmland. “This disrupted their life cycle,” says Dean. “They were in these huge flocks, and they needed vast tracks of forests for roosting and feeding ground.”
As pigeon meat began to be sold in stores as a cheap source of protein, the threat from hunters became even more significant than that of lost habitat. The pigeons’ intensely social nature, once a strength, became a liability. “Commercial hunters would get word that a flock had showed up at some locality, and the hunters would go and set off nets or just fire repeatedly with their shotguns,” Dean says. “The flock was such a tight-knit group that even as individuals were falling and dying, the rest of the flock wouldn’t leave.” Other methods of killing were crueler, with some hunters soaking grain in alcohol to make them easier to kill.
As scientists began to realize the danger that the species might actually die out, there were some last ditch efforts to save the passenger pigeons. “The Cincinnati Zoo had a standing offer of $1,000 for a mate for Martha that had been put in place about 15 years before she died,” Dean says. But the slaughter of passenger pigeons continued regardless. “That was a period of time when conservation was just getting started,” he says. “There were really no laws to protect the birds at all.” The last confirmed report of a specimen in the wild was in 1900.
Because the birds had evolved to breed in enormous colonies, all attempts at breeding small groups in captivity failed. As Martha aged, researchers realized the species was doomed. When she finally died, it was widely known that she was the last of her kind. “There was a lot of sadness. This was an early recognition of species extinction,” says Dean. “The zoo had roped off the area around her cage and instituted a quiet zone.”
Afterward, the zoo donated Martha’s body to the Natural History Museum. “They froze her up in a 300 pound block of ice and shipped her to the scientists at the Smithsonian to study and preserve,” Dean says. “It came here and she was prepared as a taxidermy mount, and also parts of her internal organs were saved here in our fluid collection.”
Nearly a century later, the story of the passenger pigeon remains a troubling portent for those concerned about the environment. “There are other species of birds, like the Carolina parakeet, that the last known individual died,” says Dean. “But we still get more phone calls and inquiries about Martha than any other. It seems like she has become an icon of the conservation movement for saving species.”
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From the Wall Street Journal, REVIEW section, Saturday/Sunday, April 5-6, 2014, Page C12:
HISTORICALLY SPEAKING
The Lesson of the Last Passenger Pigeon
Martha, the final member of her species, died during what scientists call the Sixth Extinction
April 4, 2014 9:03 p.m. ET
In April 1896, a flock of American passenger pigeons was discovered nesting in a forest outside Bowling Green, Ohio. Once the most ubiquitous bird in North America, the passenger pigeon had shrunk from countless billions to this single of flock of 250,000. News of the find was telegraphed across the country, drawing hundreds of visitors to the area.
By this time, the great bison—a powerful symbol of frontier America—had dwindled from a population of tens of millions to just a few hundred, all in zoos or reservations. Determined to prevent a similar fate for the passenger pigeon, several states had already enacted hunting bans. Seeing the birds gave conservationists hope that the restrictions were working.
Thomas Fuchs
Unfortunately, the visitors to Bowling Green weren't bird watchers but hunters, and Ohio had no such protective laws. They killed the entire flock in a day. Afterward, the train taking the carcasses to sell in New York City derailed, leaving them to rot in a ravine. Eighteen years later, the lone survivor of the species—a female bird named Martha, after George Washington's wife—died in a cage in the Cincinnati zoo.
The death of Martha is part of a much larger story that has been dubbed the Sixth Extinction. (The term was coined in the 1990s by the Kenyan paleontologist Richard Leakey ; it has been used widely ever since, as in the title of Elizabeth Kolbert's well-reviewed recent book.) The previous five waves of extinctions began in the Ordovician era about 440 million years ago, when global cooling led to the Earth's first intense ice age. A simultaneous drop in temperatures and sea levels brought about the extinction of up to 88% of all species.
But even this paled by comparison to the catastrophic death toll during the third wave—the Permian extinction—approximately 250 million years ago. In what's often known as "the Great Dying," megaton volcanic eruptions covered the planet with noxious gases, starting a chain reaction that scientists estimate ultimately led to the extinction of some 97% of the species on Earth. The wave that killed off the dinosaurs some 66 million years ago in the late Cretaceous period—involving yet more volcanic eruptions, perhaps coupled with a large asteroid hit—was just a pale copy.
The Sixth Extinction actually started tens of thousands of years ago, when Homo sapiens discovered how to hunt the lumbering mammals that then populated the Earth: the mastodon, the giant sloth, the woolly mammoth and more. By the time the first human settlements were in evidence in 10,000 B.C., these mammals were gone.
Charles Darwin mistakenly believed that extinction was an immensely slow and evolving process, regrettable but natural. But by the time his "On the Origin of Species" was published in 1859, the inhabitants of North America were already well on their way to accomplishing a mini die-off that would result in the loss of an estimated 1,000 species in just 500 years—including the colorful Carolina parakeet, the Merriam's elk, the Rocky Mountain locust and the hapless passenger pigeon.
Today, the World Wildlife Fund estimates that 3,879 species live under imminent threat. Among them are African elephants, whose ivory tusks are so sought-after in China that the current rate of poaching could lead to their extinction in less than a decade.
The problem with the term Sixth Extinction is that it implies a sense of inevitability, as though humans can't help being dangerous, like the weather and large asteroids. Yet the example of Theodore Roosevelt shows that a man (or woman) can halt inevitability in its tracks. The 26th president couldn't save the passenger pigeon, but he did help rescue the great bison by creating four national game reserves. He also protected 150 national forests, 51 bird reservations and 230 million acres of pristine land.
We don't need to hug a tree or kiss a toad, but we should all stand up for the Marthas, big and small.
—Write to amanda.foreman@wsj.com
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