Passenger Pigeons and Their Extinction

By Bruce Wright

No other human-caused extinction event has been as spectacular and as pervasive in the literature as that of the passenger pigeon (Ectopistes migratorius). However, documentation of this event relies on personal journals, newspaper and magazine articles, and a few volumes that summarize some of the events after the passenger pigeons were extinct. The prevalent message from most of the articles is that passenger pigeons, once the most abundant bird on the planet, went extinct because humans pressed forward with their desire to conquer all that was before them, in this case, the New World, and without considering the consequences. Passenger pigeons were a keystone species is what is now known as the eastern United States and portions of eastern Canada and Mexico; they drove the ecosystem, were pursued by a huge suite of predators, including Native Americans, and were of such numbers, 3-5 billion birds, they were a dominating force which must have manipulated their ecosystem with a randomness as variable as their vast and sky-blackening migrations (see Wilson 1812). Their migrations of millions of birds were necessary as they pursued berries, and fall crops of mast, mostly beechnuts (Fagus grandifolia) and acorns (Quercus spp.). Passenger pigeons were defined by their movements throughout the eastern section of North America; they spent much of their time in search of patches of mast.

Observers of the demise of passenger pigeons noted loss of habitat and over-harvest (hunting) as readily identified factors leading to their extinction. Audubon (1844) mentioned starvation and predation as possible factors. Less obvious population factors are contaminants, competition, and disease. I found evidence from reports that cast some doubt on all these factors as causes of the extinction of passenger pigeons, except disease for which I found no contradictory evidence. I think that an introduced disease caused the extinction of passenger pigeons, even if other factors exacerbated the population crash on various scales. In this book I will present an overview of what we know about passenger pigeons, and I will consider possible consequences resulting in the extinction of these interesting birds. I will provide evidence and present a disease model that helps explain how disease was the preeminent cause that led to the rapid and complete elimination of passenger pigeons in the short 30 year period at the end of the 19th century.

• Language: English
• Publisher: Bruce Wright
• Release date: Jun 7, 2013
• ISBN: 9781301907472

Bruce Wright

Bruce Wright Web site: www.environmentalaska.us Senior Scientist, Chilkat Environmental, 2013-present Senior Scientist, Knik Tribal Council, 2010-present Senior Scientist, Aleutian Pribilof Islands Association (APIA), 2005-present Project Manager, APIA, Native American Lands Environmental Mitigation Program, 2010-current Project Manager, Tanadgusix Power Corporation, TDX Village Power Group 2009-2010 Project Manager, APIA, 7 Generations, Environmental Education Project 2006-2009 Principal Investigator, APIA, Sand Point Wind Farm Bald Eagle Monitoring 2006-2009 Program Manager, APIA, Energy, 2005-current Principal Investigator, APIA, Testing and Monitoring for Paralytic Shellfish Poisoning in Aleut Communities, 2006-2014 Principal Investigator, APIA, Oil Spill Capacity Building, Preparedness and Monitoring Project, 2005-08 Director, Conservation Science Institute, 2001-2012 Chief, Office of Oil Spill Damage Assessment & Restoration, NOAA, 1989 – 2001 Program Manager, Alaska Predator Ecosystem Experiment, NOAA, May 1995 – July 2001 Project Manager, Alaska Shark Assessment Program, NOAA, 1998 – 2001 Visiting Assistant Professor of Biology, University of Alaska Southeast, 1989-2001 Fisheries Biologist/Habitat Biologist, Alaska Department of Fish and Game, 1978-1989 PUBLICATIONS BOOKS Wright, Bruce A. 2013. Great White Sharks in Alaska, 2nd Edition. https://www.smashwords.com/books/view/324785 Wright, Bruce A. 2013. Passenger Pigeons and Their Extinction. https://www.smashwords.com/books/view/324053 Wright, Bruce A., 2011. Alaska Predators, Their Ecology and Conservation. Hancock House Publishing. 119 pages. http://www.hancockhouse.com/products/alapre.htm Wright, B.A. and P. Schempf (Eds.). 2005. Bald Eagles in Alaska. Bald Eagle Research Institute. Rice, S.D., R.B. Spies, D.A. Wolfe, and B.A. Wright (Eds.). 1996. Exxon Valdez oil spill symposium proceedings. American Fisheries Society Symposium Number 18. PAPERS....... About 20 Wright, B.A., E. Donat and R. RaLonde. 2013. Life-threatening risk from paralytic shellfish poisoning in Dungeness crab in Southeast Alaska. See at http://www.environmentalaska.us/psp-in-dungeness-crab.html. Wright, B.A, 2013. Sunburned Arctic seals. 5th International Conference, Contemporary Problems of Oriental Studies, The Far Eastern State University of Humanities, Khabarovsk, Russia. http://www.environmentalaska.us/ultraviolet-radiation-uv.html. Wright, B. A., B. Hirsch and J. Lyons. July 2012. A better use of wind energy in Alaska and applicability for Russian villages. Indian Journal of Energy. Vol.1, No.1. Wright, Bruce A. 2012. Harbingers of Climate Change, Dominance of a Top Predator, Pacific Sleeper Sharks and Greenland Sharks. In; Biological Diversity and Ecological Problems in Priamurie and Adjacent Territories. Regional Scientific Work with International Participants, Far Eastern Federal University for the Humanities. Issue 3. Wright, Bruce. 2010. Salmon Swimming Against Multiple Threats. Science 19 March 2010. Vol. 327. No. 5972, p. 1452a. Wright, Bruce. 2010. Predators Could Help Save Pollock. Science 5 February 2010: 642. Costa, Pedro Reis, Keri A. Baugh, Bruce Wright, Raymond RaLonde, Natalia Tatarenkova, Stacey M. Etheridge and Kathi A. Lefebvre. 2009. Comparative determination of paralytic shellfish toxins (PSTs) using five different toxin detection methods in shellfish species collected in the Aleutian Islands, Alaska. Toxicon: 54 (2009) 313–320. Wright, B.A. 2009. Chukchi Sea Ice Out, In: Thoreau's Legacy: American Stories about Global Warming. Penguin Classics. New York, N.Y. Okey, T.A., B.A. Wright and M. Brubaker. 2007. Climate change, trans-oceanic fisheries impacts, or just variability?: Salmon shark connections. Fish and Fisheries. Volume 8, Issue 4, Pages 359 – 366. Okey, T.A. and B.A. Wright. 2005. Sufficient fuel taxes would enhance ecologies, economies, and communities. Ecological Economics 53 (2005) 1– 4. Wright, B.A. and P. Schempf. 2005. The book on bald eagles. pages 8-14. in: Wright, B.A. and P. Schempf (Eds.). 2005. Bald Eagles in Alaska. Bald Eagle Research Institute. Wright, B.A. and T.A. Okey. 2004. Creating a sustainable future? Science 304(5679):1903. Okey, T. A. and B. A. Wright. 2004. Toward ecosystem-based extraction policies for Prince William Sound, Alaska: integrating conflicting objectives and rebuilding pinnipeds. Bulletin of Marine Science. 74(3): 727-747. Heiman, M., B. A. Wright, et al. 2000. Contaminants in Alaska: Is America's Arctic at Risk? A white paper published by the Department of the Interior and the State of Alaska. Wright, B.A., J. W. Short, T. J. Weingartner, P. J. Anderson. 2000. The Gulf of Alaska. In: Seas at the Millennium: An Environmental Evaluation. Ed. C. Sheppard. Elsevier Science Ltd. Wright, B.A., and L. Hulbert. 2000. Shark abundance increases in the Gulf of Alaska. PICES Press Vol. 8, No.2, July 2000. Wright, B.A. 2000. The Exxon Valdez Oil Spill Response, Damage Assessment, Restoration and Continued Effects. pages 55-61. in: What Should We Learn from Oil Spills? Preparatory Committee for the Japan Environmental Disaster Information Center, Global Environment Information Center, Tokyo, Japan. Short, J.W., K. A. Kvenvolden, and B.A. Wright. 2000. Response to Comment on “Natural Hydrocarbon Background in Benthic Sediments of Prince William Sound, Alaska: Oil vs. Coal.” Environmental Science and Technology. 34, 2066-2067. Short, J.W., K. A. Kvenvolden, and B.A. Wright. 1999. Natural Hydrocarbon Background in Benthic Sediments of Prince William Sound, Alaska: Oil vs. Coal. Environmental Science and Technology. 33, 34-42. Loughlin, T.R., B.E. Ballachey, and B.A. Wright. 1996. Overview of Studies to Determine Injury to Marine Mammals Caused by the Exxon Valdez Oil Spill. in Rice, S.D., R.B. Spies, D.A. Wolfe, and B.A. Wright (Eds.). 1995. Exxon Valdez Oil Spill Symposium Proceedings. American Fisheries Society Symposium Number 18.

Book preview

Passenger Pigeons and Their Extinction

Written by

Bruce A. Wright

SMASHWORDS EDITION

PUBLISHED BY:

Bruce Wright on Smashwords

Passenger Pigeons and Their Extinction

Copyright © 2013 by Bruce A. Wright

Thank you for downloading this ebook which remains the copyrighted property of the author and may not be reproduced, scanned, or distributed for any commercial or non-commercial use without permission from the author. No alteration of content is allowed. Your support and respect for the property of this author is appreciated.

*****

TABLE OF CONTENTS

Introduction …3

Columbids …4

Distribution …4

Feathers, flight and migration …5

Social behavior …8

Reproduction, nests, eggs and chicks …8

Population size …10

Food, feeding ecology and landscape ecology …11

Mortality factors and extinction …13

Loss of habitat …13

Starvation …13

Competition …13

Predation ...14

Hunting …15

Inbreeding suppression …16

Contaminants …16

An experimental disease model …16

Abstract …17

Introduction …17

Methods …18

Results …19

Discussion …20

Passenger pigeon proxy …22

So, was it disease? …23

Timing of spread of trichomoniasis …25

Conclusions …26

Columbid conservation …27

Reoccurring exposure to T. gallinae …27

Globalization and the spread of diseases …28

South American eared dove extinction experiment …28

Global warming, climate change and Columbids …28

Acknowledgements …29

References …29

Glossary …34

Index …39

About the author …42

When I was in high school, I practiced falconry. It would take me nearly 40 years later that I figured out what caused the death of my red-tailed hawk. The same disease that killed my hawk was the primary cause for the extinction of passenger pigeons.

Bruce Wright 2010

In the autumn of 1813, I left my house at Henderson, on the banks of the Ohio, on my way to Louisville. In passing over the Barrens a few miles beyond Hardensburgh, I observed the pigeons flying from northeast to southwest, in greater numbers than I thought I had ever seen them before, and feeling an inclination to count the flocks that might pass within the reach of my eye in one hour, I dismounted, seated myself on an eminence and began to mark with my pencil, making a dot for every flock that passed. In a short time, finding the task which I had undertaken impracticable, as the birds poured in countless multitudes, I rose, and counting the dots then put down, found that one hundred and sixty-three had been made in twenty-one minutes. I traveled on, and still met more the further I proceeded. The air was literally filled with pigeons; the light

of noonday was obscured as by an eclipse; the dung fell in spots, not unlike melting flakes of snow; and the continued buzz of wings had a tendency to lull my senses to repose.

John James Audubon, Ornithological Biography, I (1833)

I always thought there was more to explaining the extinction of passenger pigeons than hunting or loss of habitat. I thought disease could have been important.

Richard Kocan (2005)

INTRODUCTION

No other human-caused extinction event has been as spectacular and as pervasive in the literature as that of the passenger pigeon (Ectopistes migratorius). However, documentation of this event relies on personal journals, newspaper and magazine articles, and a few volumes that summarize some of the events after the passenger pigeons were extinct. The prevalent message from most of the articles is that passenger pigeons, once the most abundant bird on the planet, went extinct because humans pressed forward with their desire to conquer all that was before them, in this case, the New World, and without considering the consequences. Passenger pigeons were a keystone species is what is now known as the eastern United States and portions of eastern Canada and Mexico; they drove the ecosystem, were pursued by a huge suite of predators, including Native Americans, and were of such numbers, 3-5 billion birds, they were a dominating force which must have manipulated their ecosystem with a randomness as variable as their vast and sky-blackening migrations (see Wilson 1812). Their migrations of millions of birds were necessary as they pursued berries, and fall crops of mast, mostly beechnuts (Fagus grandifolia) and acorns (Quercus spp.). Passenger pigeons were defined by their movements throughout the eastern section of North America; they spent much of their time in search of patches of mast.

Observers of the demise of passenger pigeons noted loss of habitat and over-harvest (hunting) as readily identified factors leading to their extinction. Audubon (1844) mentioned starvation and predation as possible factors. Less obvious population factors are contaminants, competition, and disease. I found evidence from reports that cast some doubt on all these factors as causes of the extinction of passenger pigeons, except disease for which I found no contradictory evidence. I think that an introduced disease caused the extinction of passenger pigeons, even if other factors exacerbated the population crash on various scales. In this book I will present an overview of what we know about passenger pigeons, and I will consider possible consequences resulting in the extinction of these interesting birds. I will provide evidence and present a disease model that helps explain how disease was the preeminent cause that led to the rapid and complete elimination of passenger pigeons in the short 30 year period at the end of the 19th century.

COLUMBIDS

Pigeons and doves, including passenger pigeons, are classified in the Columbiformes Order and the Columbidae Family, but they are often referred to as columbids. Worldwide there are 308 species in the order Columbiformes, and in North America there are 14 species and 6 genera. The columbid species most commonly seen around human habitation and in cities is usually the rock dove (Columba livia), also called the rock pigeon, domestic pigeon or feral pigeon. I will discuss this species throughout the book