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At times everyone feels somewhat alone. But Martha was truly alone, all alone. Living in the Cincinnati zoo, Martha was the last Passenger Pigeon remaining on earth. Her parents were dead. She had no living brothers or sisters. No relatives or friends. No one. She was the last of her kind. When she died at age 29 almost a century ago (September 1, 1914) Passenger Pigeons ceased to exist.

Zookeepers rushed Martha’s lifeless body to the Cincinnati Ice Company. Held by her feet, she was lowered into a tank of water, frozen upside down into a 300-pound block of ice and shipped to the Smithsonian Institution where her lifeless corpse remains on display today. A simple sign reads: “Extinct”.

Larger than a typical urban pigeon and weighing twice as much as Mourning Dove, Passenger Pigeons preferred forestland to crowded city streets and parks, and congregated in very large flocks. Their name came from a French word, passage, meaning “to pass by”.

The most abundant bird

And when they did pass by, their numbers were impressive. Less than 100 years before Martha’s death, the Passenger Pigeon was the most abundant bird in the country. Reliable estimates place their total number at up to 5 billion individuals, more than 30% of all birds, possibly the most abundant bird that ever lived on earth. Ornithologists reported flocks over one mile wide and 20 miles long that literally “blacken the sky”. Audubon observed a migration flight so enormous it took two days to pass. A single roost site might contain 5-7 million birds.

An old adage maintains that there is strength in numbers. Larger groups tend to have advantages over smaller groups. Winning generals deploy more troops than their enemies. Successful politicians gather more delegates.

With such a massive population the possibility that Passenger Pigeons might become extinct was inconceivable. Yet in less than a century, they were gone. From 5 billion individuals to Martha, to none.

How did 5 billions birds disappear?

How could a species so incredibility abundant become extinct is such a short period of time? What caused their dramatic decline? If you suspect humans played a lead role, you are on the right track. Although there was no single cause, man tipped the balance of nature. Loss of habitat and food combined with extensive hunting were major contributors.

As vegetarians their primary food source was “mast” — a general term for the seeds and ripening fruit of hard wood and fruit bearing trees. They loved beechnuts, acorns, and maple and elm seeds. A large flock could quickly strip a small woodlot of all edible food. Then the flock would move on. Pigeons were semi-nomadic, constantly on the move to find food. Fortunately, different types of mast matured at different times during the year. But only a fairly large forest could produce enough mast to satisfy a huge army of pigeons.

The eastern half of the country was originally heavily forested. However, as human population mushroomed, civilization moved inland and westward from the coast. Forests were rapidly cleared for farming, industry and cities. As these forests shrunk in size, finding ample food became more challenging for Passenger Pigeons.

Greater danger

Loss of food sources was not the only peril. Hunting was a more lethal danger. Early settlers quickly learned that pigeon meat was tasty. And pigeons were plentiful and easy to kill. Subsistence hunting to feed the farm family was not the major problem. Rather it was professional trappers and market hunters who killed pigeons in sufficient quantities to feed an entire city.

One throw of a net into a sleeping roost could capture hundreds of birds. A single shot might kill 5, 10 or more. The supply seemed inexhaustible. In 1874 at one roost in Michigan, a group of market hunters bagged 25,000 birds a day for 28 straight days. In 1771 Boston markets sold 50,000 pigeons per day. Pigeons were an inexpensive source of meat protein.

Squab (the young pigeon nestling) was particularly flavorful and highly prized. Pigeon hunters raided roosts taking all the squabs. As a result, few young remained to produce future generations of pigeons. Adults that did survive the hunters eventually died naturally. Reproduction rates were drastically reduced and population numbers plunged into a downward spiral toward zero.

At one time the total number of passenger pigeons was far greater than total number of sparrows and starlings combined today. Their numbers were almost unimaginable. Yet large numbers did not help them survive. Can you imagine today that starlings might be in danger of extinction?

The total population of all the currently endangered species (California Condor, Whooping Crane, Kirtland’s Warbler and others) numbers in the hundreds of birds, not thousands or millions of individuals. If 5 billion pigeons could disappear, so could today’s smaller populations if things don’t change.

Since human activity contributes to the decline of a species, changes in human activity can reverse the trend. The banning of DDT halted and reversed the threat to Bald Eagles and Ospreys. California Condors are flying free in the wild again. All the result of direct help from caring humans.

Still, in the last two centuries, five species have become extinct in the U.S. Currently the U.S. Fish & Wildlife Service lists about 50 species and subspecies as “endangered” in the continental US.

Current populations of these endangered species are very small. But as the plight of the passenger pigeon vividly demonstrates, sheer numbers do not guarantee future well-being. The most common birds in your backyard could also be at risk. Careful attention to what is happening in your yard, your city and your area can prevent another bird, maybe that cheerful Robin on your lawn, from joining Martha on display at the Smithsonian.

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