National Academy Press
2101 Constitution Avenue, N.W. Washington, D.C. 20418
NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
This report has been reviewed by a group other than the authors according to procedures approved by a Report Review Committee consisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
This study by the Board on Biology was supported by the Department of the Interior, U.S. Fish and Wildlife Service under grant number 14-16-0001-91578.
Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the views of the U.S. Fish and Wildlife Service.
Library of Congress Catalog Card No. 92-60711
International Standard Book Number 0-309-04775-7
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National Academy Press
2101 Constitution Avenue, N.W. Washington, D.C. 20418
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Copyright 1992 by the National Academy of Sciences
Printed in the United States of America
COMMITTEE ON THE SCIENTIFIC BASES FOR THE PRESERVATION OF THE HAWAIIAN CROW
W. Donald Duckworth (Chairman), President and Director,
Bishop Museum, Honolulu, HI
Tom J. Cade,
The Peregrine Fund, Boise, ID
Hampton L. Carson,
University of Hawai'i, Honolulu, HI
Scott Derrickson,
National Zoological Park, Front Royal, VA
John Fitzpatrick,
Archbold Biological Station, Lake Placid, FL
Frances C. James,
Florida State University, Tallahassee, FL
Special Advisors
Cynthia Kuehler,
Zoological Society of San Diego, San Diego, CA
Stuart Pimm,
University of Tennessee, Knoxville, TN
National Research Council Staff
Donna M. Gerardi, Study Director
Norman Grossblatt, Editor
Scott Olson, Project Assistant
Mary Kay Porter, Project Assistant
BOARD ON BIOLOGY
Harold E. Varmus (Chairman),
University of California, San Francisco, CA
Ananda M. Chakrabarty,
University of Illinois, Chicago, IL
Michael T. Clegg,
University of California, Riverside, CA
Richard E. Dickerson,
University of California, Los Angeles, CA
Richard E. Lenski,
Michigan State University, East Lansing, MI
Barbara J. Mazur,
E.I. du Pont de Nemours & Co., Wilmington, DE
Harold J. Morowitz,
George Mason University, Fairfax, VA
Daniel E. Morse,
University of California, Santa Barbara, CA
Philip Needleman,
Monsanto Company, St. Louis, MO
Mary Lou Pardue,
Massachusetts Institute of Technology, Cambridge, MA
David D. Sabatini,
New York University, New York, NY
Michael E. Soulé,
University of California, Santa Cruz, CA
Malcolm S. Steinberg,
Princeton University, Princeton, NJ
David B. Wake,
University of California, Berkeley, CA
Daniel I. C. Wang,
Massachusetts Institute of Technology, Cambridge, MA
Bruce M. Alberts (ex officio),
University of California, San Francisco, CA
National Research Council Staff
Oskar R. Zaborsky, Director
COMMISSION ON LIFE SCIENCES
Bruce M. Alberts (Chairman),
University of California, San Francisco, CA
Bruce N. Ames,
University of California, Berkeley, CA
J. Michael Bishop,
University of California, San Francisco, CA
Michael T. Clegg,
University of California, Riverside, CA
Glenn A. Crosby,
Washington State University, Pullman, WA
Leroy E. Hood,
California Institute of Technology, Pasadena, CA
Donald F. Hornig,
Harvard School of Public Health, Boston, MA
Marian E. Koshland,
University of California, Berkeley, CA
Richard E. Lenski,
Michigan State University, East Lansing, MI
Steven P. Pakes,
Southwestern Medical Center at Dallas, TX
Emil A. Pfitzer,
Hoffmann-LaRoche, Inc., Nutley, NJ
Thomas D. Pollard,
Johns Hopkins Medical School, Baltimore, MD
Joseph E. Rall,
National Institutes of Health, Bethesda, MD
Richard D. Remington,
University of Iowa, Iowa City, IA
Paul G. Risser,
University of New Mexico, Albuquerque, NM
Harold M. Schmeck, Jr.,
Armonk, NY
Richard B. Setlow,
Brookhaven National Laboratory, Upton, NY
Carla J. Shatz,
University of California, Berkeley, CA
Torsten N. Wiesel,
Rockefeller University, New York, NY
National Research Council Staff
John E. Burris, Executive Director
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Frank Press is president of the National Academy of Sciences.
The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Robert M. White is president of the National Academy of Engineering.
The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an advisor to the federal government and, upon its own initiative, to identify issues of medical care, research and education. Dr. Kenneth Shine is president of the Institute of Medicine.
The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy's purposes of furthering knowledge and of advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Frank Press and Dr. Robert M. White are chairman and vice chairman, respectively, of the National Research Council.
PREFACE
Much has been written about the unique and fragile environment of the state of Hawai'i. Formed by up-welling lava from the ocean floor, the Hawaiian archipelago is the world's most isolated island group, located some 4,000 km from the nearest continental land mass and 3,000 km north of the Marquesas Islands. The islands of Hawai'i range from sea level to over 4,000 m in elevation and receive an annual precipitation ranging from 200 mm to over 10,000 mm. Together, the isolation and diverse physiography of the islands influenced the evolution of a unique biota characterized by low phylogenetic diversity, high endemism, and spectacular adaptive radiations. Many groups of organisms—such as the silverswords (Asteraceae), lobeliads (Lobeliaceae), land snails (Achatinellidae, Amastridae, and others), pomace flies (Drosophilidae), and Hawaiian honeycreepers (Drepanidinae)—radiated from single ancestral populations into diverse assemblages of closely related species occupying a broad range of habitats.
The extraordinary array of unique life forms on the Hawaiian archipelago that evolved over millions of years has declined at an ever-increasing rate since the arrival of humans and their intentional and accidental fellow travelers—exotic plants and animals—and today Hawai'i has the distinction of being the extinction capital of the world. Relatively intact native ecosystems have generally survived only at higher elevations, and many extant species now occupy only small remnant portions of their former ranges. Hawai'i consists of only 0.02% of the land area of the United States, but it has sustained nearly 75% of the nation's documented plant and animal extinctions, and native Hawaiian species are a substantial proportion of the species included on the U.S. list of Endangered and Threatened Wildlife and Plants1
Against that tapestry of severe habitat loss and loss of biological diversity, the efforts to save a single species, such as the Hawaiian Crow (Corvus hawaiiensis), or 'Alala, might seem to have little importance. However, single-species conservation efforts can be justified on moral, ethical, legal, economic, and scientific grounds, and it is especially important to recognize that programs to save single "indicator species" can provide a foundation for broader conservation and education initiatives. Research, habitat restoration, and educational efforts undertaken for the recovery of a single endangered species clearly can benefit a wide range of species and habitats if properly designed and effectively implemented.
In response to a request from the U.S. Fish and Wildlife Service, the National Research Council's Board on Biology established the Committee on the Scientific Bases for the Preservation of the Hawaiian Crow ('Alala) in September 1991. Its task was to review the existing data pertaining to the 'Alala while focusing on several scientific issues:
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"Assess to the extent possible the causes of population trends of the 'Alala in the wild;
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"Assess to the extent possible the causes of population trends of the 'Alala in the captive population;
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"Evaluate options for action to maintain or increase numbers of the 'Alala in both the captive and wild populations;
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"Estimate the minimum viable population for survival of this species; and
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"Determine the advisability of adding genetic stock from the wild flock to the captive flock. If it is advisable, the 'form' in which this genetic material should be taken will be specified: e.g., eggs, fledglings, juvenile birds, or adults."
Current options for recovery of the 'Alala vary; they range from bringing all birds into a captive propagation program to leaving the wild population undisturbed. From the assembled data and their evaluation, the committee has developed a set of recommendations designed to assist interested parties in working effectively to aid the recovery of the 'Alala.
The committee held three meetings: two in Hawai'i (Honolulu, October 1991; Captain Cook, January 1992) and one at the Arnold and Mabel Beckman Center, Irvine, California (December, 1991). In addition, a subcommittee meeting was held at the Beckman Center (February 24–25, 1992). The committee collected and reviewed data on the 'Alala from biologists in federal and state agencies, other scientists and individuals. It visited the Olinda captive-breeding facility on the island of Maui. We are especially grateful to the owners and personnel of the McCandless Ranch on the island of Hawai'i for hosting the committee on a 2-day fact-finding trip on their property. The opportunity for the committee members in attendance to observe the 'Alala flock in nature was invaluable to the development of this report.
Many persons assisted the committee in preparing this report, and we are grateful to them. The committee is especially indebted to those who submitted information for its review:
Carolee Caffrey, University of California, Los Angeles
Robert Fleischer, National Zoological Park
Patricia Rabenold, Ohio State University
Cheryl Tarr, Pennsylvania State University
Special thanks are also due to the following persons, who were guests at committee meetings and participated in our discussions:
In Honolulu
Carter Atkinson, USFWS
Michael Buck, Hawai'i DLNR
Paul Conry, Hawai'i DLNR
Reggie David, Hawai'i Audubon Society
John Engbring, USFWS
Jon Giffin, Hawai'i DLNR
James Jacobi, USFWS
Dana Kokubun, National Audubon Society
Barbara Lee, Alala Foundation
Robert Pyle, Bishop Museum and Hawai'i Audubon Society
Karen Rosa, USFWS
Nohea Santimer, Alala Foundation
Charles Shockey, U.S. Department of Justice
Peter Simmons, McCandless Properties
Robert Smith, USFWS
Paul Spaulding, III, Sierra Club Legal Defense Fund
Carole Terry, Hawai'i DLNR
Ronald Walker, Hawai'i DLNR
Moani Zablan, Alala Foundation
On Maui, Olinda Captive Breeding Facility
Renate Gassman-Duvall, former contract veterinarian with Hawai'i DNLR
Fern Duvall, Hawai'i DNLR
Judy Pangelinan Subaitis, Hawai'i DNLR
Wayne Taka, Hawai'i DNLR
On Hawai'i Captain Cook and McCandless Ranch
Paul Banko, USFWS
Andrew Berger, University of Hawai'i
Paul Breese, Honolulu Zoo
John Phillips, Professor Emeritus, Stanford University
Cynthia Salley, McCandless Ranch
Nicholas Santimer, McCandless Ranch
Nohea Santimer, McCandless Ranch
Peter Simmons, McCandless Ranch
Throughout the course of its deliberations, the committee was careful to maintain a steady focus on the scientific evidence available concerning the 'Alala and the implications of that evidence in relation to present and future efforts for recovery. Aware of past controversy and current disputes over recovery plans and techniques, which are the responsibilities of state and federal agencies and individuals, the committee assiduously adhered to its primary task. In this
regard, the committee is grateful for the understanding and support of all parties associated with the study. The value of this approach, coupled with the considerable talent and experience of the committee members, is evidenced by the information and results described in the report.
Finally, the committee wishes to acknowledge with gratitude and admiration the vital role played by the National Research Council staff in all aspects of the project. The dedicated professionalism of NRC study director Donna Gerardi facilitated and expedited the committee's activities throughout the study. In addition, Alvin Lazen and Norman Grossblatt added considerable experience and effort to the endeavor.
W. Donald Duckworth, Chairman
Committee on the Scientific Bases for the Preservation of the Hawaiian Crow
May 1992