National Academies Press: OpenBook

Science and the Endangered Species Act (1995)

Chapter: Front Matter

Suggested Citation:"Front Matter." National Research Council. 1995. Science and the Endangered Species Act. Washington, DC: The National Academies Press. doi: 10.17226/4978.
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About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please iv NATIONAL ACADEMY PRESS 2101 Constitution Ave., 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 mem- bers 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 con- sisting of members of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The project was supported by the Department of the Interior under Contract No. 14-48-0009-92-010. Library of Congress Cataloging-in-Publication Data Science and the Endangered Species Act / Committee on Scientific Issues in the Endangered Species Act, Board on Environmental Studies and Toxicology, Commission on Life Sciences. p. cm Includes bibliographical references and index. ISBN 0-309-05291-2 1. Endangered species—United States. 2. Endangered species—Law and legislation—United States. 3. Habitat conservation—United States. I. National Research Council (U.S.). Committee on Scientific Issues in the Endangered Species Act. QH76.S38 1995 333.9516'0973—dc20 95-33322 Copyright 1995 by the National Academy of Sciences. All rights reserved. Printed in the United States of America First Printing, October 1995 Second Printing, February 1998 use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please v COMMITTEE ON SCIENTIFIC ISSUES IN THE ENDANGERED SPECIES ACT MICHAEL T. CLEGG (Chair), University of California, Riverside, Calif. GARDNER M. BROWN, JR., University of Washington, Seattle, Wash. WILLIAM Y. BROWN, RCG/Hagler Bailly Inc., Arlington, Va. WILLIAM L. FINK, University of Michigan, Ann Arbor, Mich. JOHN HARTE, University of California, Berkeley, Calif. OLIVER A. HOUCK, Tulane University, New Orleans, La. MICHAEL LYNCH, University of Oregon, Eugene, Oreg. LYNN A. MAGUIRE, Duke University, Durham, N.C. DENNIS D. MURPHY, Stanford University, Stanford, Calif. PATRICK Y. O'BRIEN, Chevron Research & and Technology Company, Richmond, Calif. STEWARD T. A. PICKETT, Institute of Ecosystem Studies, Millbrook, N.Y. H. RONALD PULLIAM, University of Georgia, Athens, Ga., resigned 5/31/94 KATHERINE RALLS, Smithsonian Institution, Washington, D.C. BERYL B. SIMPSON, University of Texas, Austin, Tex. ROLLIN D. SPARROWE, Wildlife Management Institute, Washington, D.C. DAVID W. STEADMAN, New York State Museum, Albany, N.Y. JAMES M. SWEENEY, Champion International Corporation, Washington, D.C. Staff DAVID J. POLICANSKY, Project Director PATRICIA PEACOCK, Staff Officer (until 02/03/95) LEE R. PAULSON, Editor ADRIÉNNE DAVIS, Senior Project Assistant Sponsor Department of the Interior use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please vi BOARD ON ENVIRONMENTAL STUDIES AND TOXICOLOGY PAUL G. RISSER (Chair), Miami University, Oxford, Ohio MICHAEL J. BEAN, Environmental Defense Fund, Washington, D.C. EULA BINGHAM, University of Cincinnati, Cincinnati, Ohio EDWIN H. CLARK II, Clean Sites, Inc., Alexandria, Va. ALLAN H. CONNEY, Rutgers University, Piscataway, N.J. ELLIS COWLING, North Carolina State University, Raleigh, N.Car. JOHN L. EMMERSON, Eli Lilly & Company, Greenfield, Ind. ROBERT C. FORNEY, Unionville, Pa. ROBERT A. FROSCH, Harvard University, Cambridge, Mass. KAI LEE, Williams College, Williamstown, Mass. JANE LUBCHENCO, Oregon State University, Corvallis, Ore. GORDON ORIANS, University of Washington, Seattle, Wash. FRANK L. PARKER, Vanderbilt University, Nashville, Tenn. GEOFFREY PLACE, Hilton Head, S.Car. DAVID P. RALL, Washington, D.C. LESLIE A. REAL, Indiana University, Bloomington, Ind. KRISTIN SHRADER-FRECHETTE, University of South Florida, Tampa, Fla. BURTON H. SINGER, Princeton University, Princeton, N.J. MARGARET STRAND, Bayh, Connaughton & Malone, Washington, D.C. GERALD VAN BELLE, University of Washington, Seattle, Wash. BAILUS WALKER, JR., Howard University, Washington, D.C. Staff JAMES J. REISA, Director DAVID J. POLICANSKY, Associate Director and Program Director for Natural Resources and Applied Ecology CAROL A. MACZKA, Program Director for Toxicology and Risk Assessment LEE R. PAULSON, Program Director for Information Systems and Statistics RAYMOND A. WASSEL, Program Director for Environmental Sciences and Engineering use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please vii COMMISSION ON LIFE SCIENCES THOMAS D. POLLARD (Chair), Johns Hopkins Medical School, Baltimore, Md. BRUCE N. AMES, University of California, Berkeley, Calif. JOHN C. BAILAR III, McGill University, Montreal, Quebec MICHAEL BISHOP, Hooper Research Foundation, University of California Medical Center, San Francisco, Calif. JOHN E. BURRIS, Marine Biological Laboratory, Woods Hole, Mass. MICHAEL T. CLEGG, University of California, Riverside, Calif. GLENN A. CROSBY, Washington State University, Pullman, Wash. MARIAN E. KOSHLAND, University of California, Berkeley, Calif. RICHARD E. LENSKI, Michigan State University, East Lansing, Mich. EMIL A. PFITZER, Hoffmann-La Roche Inc., Nutley, N.J. MALCOLM C. PIKE, University of Southern California School of Medicine, Los Angeles, Calif. HENRY C. PITOT III, University of Wisconsin, Madison, Wisc. JONATHAN M. SAMET, The Johns Hopkins University School of Medicine, Baltimore, Md. HAROLD M. SCHMECK JR., Armonk, N.Y. CARLA J. SHATZ, University of California, Berkeley, Calif. SUSAN S. TAYLOR, University of California at San Diego, La Jolla, Calif. P. ROY VAGELOS, Merck & Company, Whitehouse Station, N. J. JOHN L. VANDEBERG, Southwestern Foundation for Biomedical Research, San Antonio, Tex. PAUL GILMAN, Executive Director use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please viii T he N ational Academy of Sciences i s 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 Acade my has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce Alberts 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. Harold Liebowitz 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 adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Kenneth I. 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 advising the federal government. Functioning in accordance with general policies determined by the use the print version of this publication as the authoritative version for attribution. 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. Bruce Alberts and Dr. Harold Liebowitz are chairman and vice chairman, respectively, of the National Research Council. www.national-academies.org

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please PREFACE ix Preface The Endangered Species Act (ESA) is an important legislative tool for the protection of threatened and endangered species in the United States. The ESA asserts a legal claim on behalf of those species in the United States to habitat that sometimes conflicts with competing management goals for both private and public lands. It is inevitable that these conflicts play out in the political arena. Our committee was asked to provide advice on scientific aspects of the ESA and to consider whether the act is "protecting endangered species and their habitats." We have endeavored to restrict our advice to the areas where science can better inform the public policy debate. The distinction between science and public policy is often fuzzy, because the possession of scientific knowledge and the implementation of that knowledge are so closely linked. Our goal in this report has been to explore and illuminate the knowledge side of the equation. Since the original passage of the ESA in 1973, scientific knowledge has been anything but static. Our understanding of biological species, in terms of their genetic and phylogenetic integrity, has greatly expanded since 1973. A rich array of new experimental tools has been acquired from both genetics and computational biology during the past two decades, and these have helped to drive a revolution in the traditional sciences of taxonomy and systematics. At the same time, new theoretical constructs have been elaborated that have given greater depth to definitions of species. Species are composed of systems of populations (metapopulations) that have both temporal and spatial dimensions. The temporal history of individual species and of the migrating continental land masses that contain use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please PREFACE x terrestrial habitats is known in much greater detail today than in 1973. The earth is dynamic and contemporary biological diversity is the unique realization of this long history of change. The time scales involved in biological change are long relative to human generations and, as a consequence, it is easy for us to see the biological world as static. Nothing could be further from the truth. Modern biology reveals that species are reservoirs of unique genetic adaptations to multifaceted physical and biological environments. The accumulation of these diverse adaptations is the result of a shared evolutionary history that typically involves hundreds of thousands of years of genetic continuity. The extinction of a species constitutes the irreversible loss of a suite of unique genetic adaptations that have been acquired (much like interest) over a long history of investment. Rates of extinction are uneven over geological time. Several episodes of major extinction are now recognized, including the Permian-Triassic event (245 million years ago), when approximately 65% of terrestrial species became extinct, and the Cretaceous-Tertiary event (65 million years ago), when approximately 90% of terrestrial and marine reptiles became extinct. When viewed on a global scale, the present era constitutes yet another major episode of biological extinction. In contrast to the past, however, the present cause of extinction is a single biological species that has become so successful and so exploitive that it threatens to destroy the very capital that is necessary for its own long-term survival. That single species—humankind—is capable of rational analysis and planning, so that it can influence its own long-term destiny. The earth's non-human biota is crucial to humans' long-term survival. We depend on the photosynthetic capability of green plants for the oxygen that we breathe and for virtually all of our food and energy requirements. The ability of green plants to grow is in turn dependent on a fixed supply of nitrogen (nitrates and nitrites) that are largely the product of a specialized group of microorganisms (Rhizobia). Many of our modern drugs have been derived from biotic sources. The list of human dependencies on the complex web of biological species is virtually endless. Habitat, the spatial dimension of species, is absolutely crucial to species survival. Habitat is the theater in which the network of interactions between the physical and biological worlds play out. The landscape theory of habitat emphasizes the heterogeneity, complexity, and dynamic character of the physical and biological environment. The metapopulations of species are distributed on this shifting mosaic. If these are the scientific realities, then how do we match science to wise habitat conservation? The authors of the ESA recognized that species conservation must include strong provisions for habitat conservation. These provisions included a trigger (threatened or endangered status of a species) that caused certain legal prohibitions (jeopardy and taking restrictions). The law provides for use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please PREFACE xi the recovery of species through the designation of critical habitat and through the elaboration and implementation of recovery plans. During the 20-year evolution of the ESA, additional provisions have been added, including additional mechanisms for habitat conservation, and others aimed at the resolution of conflicts engendered by ESA prohibitions. The committee was not charged with reviewing how the ESA is implemented by various federal agencies and did not directly address this question. We do, however, have several recommendations that would help improve the administration of the ESA if they were adopted (see Chapters 4 and 10, for example). In general our committee finds that there has been a good match between science and the ESA. There are, of course, points where the agreement between science and the ESA is poorer. These include lack of timely designation of endangered or threatened status and similarly timely removal from these categories when recovery goals have been achieved. Survival habitat should be identified and designated for protection if necessary when species are listed as endangered. We have been able to align the "distinct population segment" language of the ESA with our contemporary understanding of evolutionary units. We hope that such alignment helps to achieve Congress's intent that distinct population segments be listed only sparingly and on a sound scientific basis and thus reduces the danger that the ESA itself could be jeopardized by carrying that language to an absurd extreme. The analytical tools to evaluate species health have been greatly developed in recent years. The emergence of extinction theory from population genetics and ecology, the combination of demography and genetics in population viability analysis and the extension of risk analyses into the realm of biological conservation promise to lead us to wiser allocations of effort in the future. The field of ecosystem management has also emerged as a significant field of applied biology, in part as a response to the need for a more global view of conservation imperatives. The rich growth of these areas of science has also illuminated areas where our knowledge is still inadequate. In response to the charges given our committee, we attempt to identify areas of critical scientific uncertainty. To paraphrase the great 20th century ecologist G. E. Hutchinson, species are the actors in the ecosystem theater. To sustain a viable future for our descendants, we must find ways to preserve both species and ecosystems. The ESA is a critically important part of our efforts to conserve species and thereby conserve ecosystems. By virtue of the habitat restrictions that accompany endangered status, species that happen to share habitat with an endangered species gain a measure of protection. The 20-year history of the ESA has validated its focus on species endangerment. Species are objective entities that are easily recognized. Their health and needs can be assessed and sound scientific management plans can be implemented. use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please PREFACE xii Despite this, the task of managing each of the vast multitude of species on a case-by-case basis is beyond human capabilities. This is further compounded by the fact that many species remain undescribed. A challenge for the future is to find more integrated mechanisms to sustain both species and ecosystems that do not depend on case- by-case management. It was my great good fortune to work with a knowledgeable, effective, and collegial committee. The various chapters of this report are the product of much hard work and spirited debate. I want to express my deep gratitude to the committee—including H. Ronald Pulliam, who resigned from the committee when he assumed the directorship of the National Biological Service in May 1994—for their wisdom, patience, and cheerful acceptance of the tasks imposed by this project. On behalf of the committee, I thank Project Assistant Adriénne Davis for attending to our many needs. Staff Officer Patricia Peacock was a source of much practical experience in conservation policy and she was a diligent editor and critic. Project Director David Policansky contributed his vast experience in science policy, especially in the realm of conservation policy, to this project. David Policansky and Pat Peacock also wrote, rewrote and edited many sections of this report. They contributed greatly to the finished product. Finally, thanks to the many representatives of public agencies—especially the Fish and Wildlife Service—and private groups who made written and oral presentations to our committee. They added an essential dimension to our understanding of the complex issues that surround the ESA. MICHAEL T. CLEGG CHAIRMAN use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONTENTS xiii Contents Executive Summary 1 Introduction 1 The Present Study 3 Extinctions 4 The Species Concept 5 Habitat 7 Recovery, 8 Conservation Conflicts Between Species 10 Estimating Risk 11 Making ESA Decisions in the Face of Uncertainty 12 Timing 14 Beyond the Endangered Species Act 14 Science, Policy, and the ESA 16 1 Introduction 18 History 18 The Present Study 21 References 23 2 Species Extinctions 24 Extinctions Over Geological Time 24 Prehistoric Human Impact on Continental Ecosystems 27 Prehistoric Human Impact on Island Ecosystems 30 Relating the Past to the Present 32 use the print version of this publication as the authoritative version for attribution.

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONTENTS xiv Conclusions and Recommendations 38 References 40 3 Species Definitions And The Endangered Species Act 46 Historical Use of the Term Species in Implementation of the Endangered Species Act 47 History of Species Concepts Before and After the Endangered Species Act 51 A Concept of Species for the Purposes of the ESA 56 Conclusions and Recommendations 67 References 68 4 The Role of Habitat Conservation and Recovery Planning 71 The Importance of Habitat 71 The Role of Habitat Conservation Under the ESA 73 Critical Habitat and Federal Activities 75 Private Activities and Habitat Conservation Planning 78 Recovery Planning 80 Natural Community Conservation Planning Program and Coastal Sage Scrub Community of 84 Southern California Habitat-Related Standards 89 Conclusions and Recommendations 91 References 93 5 Modern Perspectives of Habitat 94 Landscapes and Populations 97 Sources and Sinks 98 Metapopulations 99 Spatially Explicit Models 100 A Spatial Perspective and Population Viability Analysis 103 Conclusions 105 References 106 6 Conservation Conflicts Between Species 111 Interactions of Species in Nature 111 Northern Goshawk and Mexican Spotted Owl 113 Winter-Run Chinook Salmon and Delta Smelt 113 use the print version of this publication as the authoritative version for attribution. Bachman's Sparrow and Red-Cockaded Woodpecker 116 Marine Mammals and Salmonids 117 Conclusions 120 Recommendations 121 References 121

About this PDF file: This new digital representation of the original work has been recomposed from XML files created from the original paper book, not from the original typesetting files. Page breaks are true to the original; line lengths, word breaks, heading styles, and other typesetting-specific formatting, however, cannot be retained, and some typographic errors may have been accidentally inserted. Please CONTENTS xv 7 Estimating Risk 124 Estimating the Risk of Extinction 125 Sources of Risk 125 Limitations of Our Ability to Estimate Risk 141 Conclusions and Recommendations 142 References 143 8 Making ESA Decisions in the Face of Uncertainty 148 Decisions Required Under the ESA 148 The Need for New Approaches to Decision Making 149 Providing Objective Risk Standards 152 Using Structured Approaches to Decision Making 157 Conclusions and Recommendations 174 References 176 9 Areas of Scientific Uncertainty 179 Ecosystem-Based Protection 179 Inadequate Knowledge of Species and Their Roles in Ecosystems 180 Estimation of the Risk of Extinction 181 Lack of Basic Information 182 The Protection of Genetic Diversity 184 Feasible Management Strategies 184 Valuing Rarity 186 References 190 10 Beyond the Endangered Species Act 193 Is the ESA Working? 193 Reducing Extinction 194 Recovery Success 195 Protection of Ecosystems 198 The Future: Beyond the Endangered Species Act 200 Science, Policy, and the ESA 202 References 203 use the print version of this publication as the authoritative version for attribution. Appendixes A Letter from Congress Requesting ESA Study 207 B Endangered Species Act 211 C Biographical Information on Committee and Staff 259 Index 263

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The Endangered Species Act (ESA) is a far-reaching law that has sparked intense controversies over the use of public lands, the rights of property owners, and economic versus environmental benefits.

In this volume a distinguished committee focuses on the science underlying the ESA and offers recommendations for making the act more effective.

The committee provides an overview of what scientists know about extinction—and what this understanding means to implementation of the ESA. Habitat—its destruction, conservation, and fundamental importance to the ESA—is explored in detail.

The book analyzes:

  • Concepts of species—how the term "species" arose and how it has been interpreted for purposes of the ESA.
  • Conflicts between species when individual species are identified for protection, including several case studies.
  • Assessment of extinction risk and decisions under the ESA—how these decisions can be made more effectively.

The book concludes with a look beyond the Endangered Species Act and suggests additional means of biological conservation and ways to reduce conflicts. It will be useful to policymakers, regulators, scientists, natural-resource managers, industry and environmental organizations, and those interested in biological conservation.

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