The Passenger Pigeon: A Tale of Extinction

Martha died at 1 PM on September first, 1914 in the Cincinnati Zoo.  Her reported age was 29: however, her actual age was undetermined.  Martha was the last known living Passenger Pigeon (Ectopistes migratorius) and her death heralded the extinction of a species.  Martha’s preserved body lies in the Smithsonian’s collections at the National Museum of Natural History.  Martha began her life in Wisconsin having been raised in Whittaker’s  aviary in Milwaukee before she was given to the Cincinnati Zoo.  One can visit the web site http://www.mnh.si.edu/onehundred years/featured objects/martha2.html to understand the meaning of her loss and the stories we must tell about ourselves.  The last known Passenger Pigeon reported in Wisconsin was shot in Babcock, September 1899, by James Varney while he and companions were hunting Prairie Chickens (Tympanuchus cupido).  Undocumented reports suggest that Passenger Pigeons were still seen in Wisconsin in the early 1900’s.

Biologists, both past and present, consider the Passenger Pigeon to arguably have been the most abundant bird on the planet.  Its population has been estimated to be up to five billion birds, with a more conservative estimate reported to be about three billion.  John James Audubon estimated a migrating flock of pigeons to be about two billion birds that required three days to pass.  Passenger pigeons inhabited the deciduous forests of eastern United States, forming large and complex social groups.  Perhaps it was this social advantage to their life that also sealed their fate, making them easy targets for hunters.  Native Americans used them as food, but saw them in the context of a whole and not a resource to be exploited.  Europeans, however, armed with guns saw them as an easily exploited limitless resource. And, with the western expansion of the railroad, the pigeons, easily harvested, could be packed into containers, and quickly shipped to the eastern markets for distribution to a growing populace.  The birds were readily collected because of easy access to their nesting and roosting sites.  Even as the population of pigeons was crashing in the late 1800’s, the birds were still harvested by the millions.

A. W. Schorger, a Wisconsin naturalist and chemist by training, amassed data from all available sources reconstructing the life history of the Passenger Pigeon.  His work, published in 1955, was entitled: The Passenger Pigeon: Its Natural History and Extinction.  Every aspect of the pigeon was examined, including its behavior, feeding methods, migration, roosting habits, nesting and its encounter with both Native Americans and white settlers.  At the time of Audubon, Schorger estimated that one of every four birds in the US was a Passenger Pigeon.  The conclusion he reached, contrary to some that suggested the pigeon’s demise was caused by diminishing food resources, was that the truth of their extinction was ugly: man had caused the extinction of this once beautiful and abundant bird.

The Passenger Pigeon deeply marked the forest ecosystem in which it thrived, and their absence in turn resulted in post extinction consequences that affect us today.  Because of the enormous numbers of pigeons, the forest canopy was often damaged due to their nesting and roosting activity.  The pigeon’s excrement that accumulated to a depth of several inches on the forest floor provided not only fuel for forest fires, but also repressed the growth of many sensitive understory plants.  Interestingly, because of this “pigeon effect” on the forest landscape, Deer Mice (Peromyscus maniculatus) became benefactors in the post extinction effects of the “restored” landscape.  David Blockstein, a student of Stan Temple (Beers-Bascom Professor Emeritus, Forestry and Wildlife Ecology at University of Wisconsin/ Madison), suggested that Deer Mice had been limited in their movement through these pigeon “engineered” landscapes (Science, 1998: Vol. 279 No. 5358, p.1831).  Because of the abundance of pigeons, tree seeds, which the Deer Mice also fed on, were depleted.  However, following extinction of the pigeon, ample supplies of acorns and other tree seed were now available. Consequently Deer Mouse populations exploded, expanding their range using these nutrient rich forests as their dispersal corridors.  Unfortunately, Deer Mice harbor Deer Ticks (Ixodes scapularis) that transmit the bacterium Borrelia burgdorferi, which causes Lyme disease.  With the spread of Deer Mice and other mammals, Lyme disease has been brought to our doorsteps.  Lyme disease, unknown for years, has always been present, but restricted to very isolated locales in New England.  It was only recently that Lyme disease and its vectors were identified, and only after the disease had spread throughout the East and Midwest. 

As humans, we do not like to be told that our actions have caused harm to another, or at worst, caused a species to become extinct.  To help us to deal with this assault to our principles, and offer an admission of our actions, monuments have been erected to the Passenger Pigeon in several states where the bird was once found.  Wisconsin honors the passing of the Passenger Pigeon in two ways: by naming the Journal of the Wisconsin Society for Ornithology the Passenger Pigeon, and by erecting a monument to the pigeon in Wyalusing State Park.  The monument was originally dedicated in 1947, with Aldo Leopold providing the inscription.  (See Interest Box for an excerpt of this poignant memory.)  The monument is a bronze plaque, set in a limestone edifice, with the likeness of a Passenger Pigeon standing on an oak branch engraved with the words: “Dedicated to the last Wisconsin Passenger Pigeon shot at Babcock, Sept. 1899.  This species became extinct through the avarice and thoughtlessness of man.”

Aldo Leopold, incensed by the extinction of the Passenger Pigeon, asked why we mourn the loss of a species?  In an emotional homily, Leopold suggested:  “There will always be pigeons in books and in museums, but these are effigies and images, dead to all hardships and to all delights.  Book-pigeons cannot dive out of a cloud to make a deer run for cover, nor clap their wings in thunderous applause of mast-laden woods.  They know no urge of seasons; they feel no kiss of sun, no lash of wind and weather; they live forever by not living at all.”  Leopold went on to warn us of telling pointed parables: “We who erect this monument are performing a dangerous act.  Because our sorrow is genuine, we are tempted to believe that we had no part in the demise of the pigeon.”  Because people such as ourselves caused the extinction, we believe it is “more important to multiply people and comforts than to cherish the beauty of the land in which we live.  What we are doing here today is publicly to confess a doubt whether this is true.”  Leopold concluded with the thought: “This then, is a monument to a bird we have lost, and to a doubt we have gained.”

With rapid advances in genetic manipulation, thoughts of reviving the Passenger Pigeon are currently being entertained.  This, I guess, would be the ultimate redemption for our actions.  The process, although complicated, would involve harvesting genetic material from preserved Passenger Pigeons, and inserting this information into stem cells derived from the Band-tailed Pigeon (Patagioenas fasciata), the Passenger Pigeon’s closest living relative.  And, viola, we have Jurassic Park revisited.  Unfortunately, as Stan Temple suggests, this is easier said than done.  The forest landscapes of today are entirely different from the past, and, because the Passenger Pigeon survived in large social units requiring huge numbers of individuals, the exercise of reversing this extinction would be extremely difficult.  Stan suggests that efforts would be better spent preventing the extinction of future species, and if the need to “recreate” were paramount, the Ivory-billed Woodpecker (Campephilus principalis) would be a better candidate.  The Ivory-billed Woodpecker lived in small groups, and some of their habitats remain largely intact.

The State of Wisconsin and the Wisconsin Society for Ornithology will commemorate the 100th anniversary of the demise of the Passenger Pigeon on 15 May 2014 in Wyalusing State Park.  It is most fitting that Stan Temple, Aldo Leopold’s replacement at UW Wildlife Department, will be the featured speaker.  Like A. W. Schorger, Stan has amassed all written material on the Passenger Pigeon to date, and used this information for the revision and reissue of the publication Silent Wings: A Memorial to the Passenger Pigeon first edited by Walter E Scott, and published in 1947.  As a special treat to Woodland Dunes, Stan Temple will be here to tell the story in person at the Bird Breakfast on 10 May.

The message of the fate of the Passenger Pigeon should be a sobering reminder that human activity not only affects the lives of humans, but also the lives of all living things. Too easily we forget that we share this planet with all living creatures.  And, history does not end with this conversation about the Passenger Pigeon.  Recently in the journal Proceedings of the National Academy of Sciences, it was predicted that one in ten bird species in this country would become extinct by the end of this century.  This will have enormous consequences to the life of every creature, human and nonhuman.  Too bad the creative genius of Pete Seeger, through his song, cannot provide inspiration and direction for changing the course of this ecological horror and its devastating consequences.

Written by: Chuck Sontag

Acknowledgement: Although I accept responsibility for the prose, Peter Weber, Professor Emeritus/SUNY Oswego generously provided his talent to clarify its meaning. For this I am especially grateful. Thanks for the help you have given in getting this project finished.


 

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