By Eileen Dowd Stukel
Originally published in the January/February 2005 edition of the SD Conservation Digest.
"I have seen them move in one unbroken column for hours across the sky, like some great river, ever varying in hue; and as the mighty stream sweeping on at sixty miles an hour, reached some deep valley, it would pour its living mass headlong down hundreds of feet, sounding as though a whirlwind was abroad in the land. I have stood by the grandest waterfall of America and regarded the descending torrents in wonder and astonishment, yet never have my astonishment, wonder, and admiration been so stirred as when I have witnessed these birds drop from their course like meteors from heaven." S. Pokagon, 1895
"These birds" were passenger pigeons (Ectopistes migratorius), a legendary North American species that was trapped, shot, and harassed to extinction a century ago. What remain are accounts such as this, museum specimens, and old photos of a species that likely numbered in the billions. Anyone with an interest in rare species knows a little about the passenger pigeon as one of the species we've lost forever. Surprisingly little study was completed on this bird, and much of what we know was pieced together from newspaper accounts, scientific articles, word-of-mouth, and correspondence. Arlie Schorger published "The Passenger Pigeon - Its Natural History and Extinction" in 1955, and this article draws heavily on Schorger's work.
Passenger pigeons were similar in appearance to the mourning dove, but they were larger and more colorful. Males were 16 1/2 inches from the top of the head to the tip of the tail, with a metallic sheen on the back of the neck. Large breast muscles and long pointed wings contributed to their tremendous speed, maneuverability, and nickname - "blue meteor." A distinctive feature was the sparkling, ruby-colored eyes. Their erect posture gave them a regal bearing.
Pity the passenger pigeon that wanted to spend some quiet time alone. These were flocking birds like no other, moving about to exploit the vast food supplies needed for their nomadic congregations, giving rise to an early common name, birds of passage. The passenger pigeon was tied to the eastern deciduous forests because of the abundance of beech and oak trees, which provided mast in the form of beechnuts, acorns, and, to a lesser extent, chestnuts. A single bird might hold as many as 17 acorns in its crop. Beechnuts have very high levels of fat and protein, and, during the passenger pigeon's peak populations, beech trees produced a good mast crop every other year. Summer foods included berries and other soft fruits, earthworms, caterpillars, and snails. Passenger pigeons were very attracted to salt deposits. Birds sometimes damaged cultivated grain crops. According to one account, the birds "did so much damage to crops that the Bishop of Quebec was more than once forced to excommunicate them." According to Schorger, the first underground grain seeder was rumored to have been built in 1860 in Horicon, Wisconsin, in response to passenger pigeon depredation on grain sown aboveground.
Nesting colonies were called nestings, and their size and density defy belief. Birds congregated in northern sites in early spring, often before the snow was gone. A site typically wasn't used for two years in a row, although birds might use the same general area if it could accommodate their nesting and foraging needs. Once a site was chosen, it appeared that every tree was occupied. Nestings were often long and narrow in shape, probably to allow adult birds easy entry and exit from the nests. What may have been the largest nesting described was in Wisconsin in 1871. One hundred miles long and 3-10 miles wide, this nesting had 1 to 50 nests in every oak tree, probably because of the area's abundant acorns. Some observers believed that birds remembered areas with good fall mast crops and returned to nest there the following spring, while others thought nesting flocks responded to the findings of spring scouting birds. We'll never know for sure.
Nesting was extremely well coordinated within a colony. Following a 3-day courtship, the female spent another 3 days building the twig nest with her mate's assistance. The nest was usually situated on a limb near the trunk of a tree. Each female laid a single egg. Both parents helped with the 13-day incubation. The male took his turn from mid-morning through mid-afternoon, with the female on duty for the rest of the day and night. Both parents fed the chick "pigeon milk" for about 6 days. This curdlike substance, produced in the parent's crop, was high in lipids, proteins, minerals, and vitamins.
Pigeon milk was gradually replaced by softened foods normally eaten by the adults. When chicks were about 2 weeks old, a startling thing happened in the nesting. Following one last feeding, the adults abandoned their chicks en masse. The extremely fat squabs stayed in the nests for the next day or two, likely begging for more food from the absent adults; then they fluttered to the ground. Several days later, chicks could fly well enough to escape capture.
William French published this description of the movements of the mass of chicks: "When the young birds fluttered from the nests in large numbers they started at once and kept going ahead, in spite of the wild animals and hawks that killed many of them. If they came to a road they crossed it; a stream, they flew over; or they fell exhausted into the water and, flapping their wings, swam to the other shore and ran on into the night."
Most passenger pigeons nested only once a year. Following the nesting season, flocks sometimes moved farther north before a month-long fall migration that began at the end of August. Seasonal movements were somewhat unpredictable for this species, since the need for adequate food and roosting space overrode all other considerations. Passenger pigeons wintered as far north as the Ohio River Valley in Ohio and Pennsylvania, although more typical wintering areas included Arkansas, southeastern Missouri, Tennessee, and North Carolina and portions of the Gulf Coast and sites in Texas and northern Florida.
The passenger pigeon faced natural enemies and other threats, such as late spring snowstorms and harvest by Native Americans, but their sheer numbers swamped the effects of these losses. The amazing nesting concentrations didn't escape the attention of settlers and the rural poor. Birds were salted, pickled, smoked, or dried. Pigeon feathers were used for bedding, and pigeon fat was highly sought after. Squabs were the most desired food, followed by birds kept and fed in captivity, then by birds taken in early fall.
Passenger pigeons were harvested in a variety of ways. Squabs were dislodged from nests with long poles, trees were cut to harvest squabs, and blunt arrows were shot into the base of a nest to cause the squab to leap out. Leaves and other plant material were burned beneath nests to force squabs to jump out. Nets were set along flight paths and at roost sites. Netters took advantage of the birds' attraction to salt by netting at salt springs or baiting nets with salt. Most netters worked near nestings, taking both young of the year and breeding adults. Trappers used live birds as decoys (stool pigeons). The stool pigeon was "blinded" to keep it from leaving the "stool." Blinding involved sewing the eyelids partially shut. The stool pigeon might be fitted with boots that were strapped onto a stick. This allowed a handler to make the bird flutter, an action that drew wild birds in to join the stool pigeon as it appeared to be landing to feed. Live birds were in high demand for trapshooting. Schorger reports that 20,000 birds were used at one shoot in Syracuse, New York in 1877.
The mid-1800s saw great expansion of U.S. railroads, allowing products to reach major eastern cities more quickly. This era sealed the fate of the passenger pigeon. Shooters converged on nestings, exploiting new transcontinental telegraph lines to learn of nesting locations. New York's game market used 300,000 passenger pigeons annually during the mid-1850s. Nearly 2 million birds were harvested from a nesting near Plattsburg, New York in 1851, with dealers paying 31 to 56 cents per dozen. At times, birds sold for a penny apiece; when supply exceeded demand, birds were given away or fed to hogs.
Shooting was the most destructive harvest method. The industry supported many more shooters than trappers. Shooting at or near nestings harvested adults needed to care for the single chick and also drove adults from nests before chicks were old enough to survive without parental care. Thousands upon thousands of birds were wasted. Squabs were ejected from nests when they were too young and too small to be used, shooters didn't bother to retrieve many birds, and pigeons were wasted due to poor shipping or storage methods. Not to worry - the supply was endless. Or was it?
As eastern deciduous forests were cleared, passenger pigeons had fewer options for nesting and roosting areas. Shooting and trapping of adults and squabs, often of nearly all members of a nesting, tipped the balance against the passenger pigeon. As a result of unrelenting harvest pressure and increasing competition for fewer birds, the species could not produce enough young to offset annual losses. A species can't operate in the red for long. In response to concerns about the species' decline, various laws were passed from the 1870s on, but they were too little and too late.
The American Ornithologists' Union meeting in 1909 included a report on how to determine whether the passenger pigeon was extinct, and a reward of $1,200 was offered for proof of even a single nest. The reward deadline was October 1, 1911, but it was extended until October 31, 1912 and went unclaimed. A bird called Martha, the last member of her species on earth, died in captivity in 1914.
Aldo Leopold is often called the father of wildlife conservation. His thoughts on the extinction of the passenger pigeon included this passage:
"There will always be pigeons in books and museums, but these are effigies and images, dead to all hardships and to all delights. Book-pigeons can not dive out of a cloud to make the deer run for cover, or clap their wings in thunderous applause of mast-laden woods. Book-pigeons cannot breakfast on new-mown wheat in Minnesota, and dine on blueberries in Canada. They know no urge of seasons, no lash of wind and weather. They live forever by not living at all."
A. Leopold, 1947