Plant and Animal Endemism in California
Plant and Animal
Endemism in California
Susan P. Harrison
UNIVERSITY OF CALIFORNIA PRESS
Berkeley•Los Angeles•London
University of California Press, one of the most distinguished university presses in the United States, enriches lives around the world by advancing scholarship in the humanities, social sciences, and natural sciences. Its activities are supported by the UC Press Foundation and by philanthropic contributions from individuals and institutions. For more information, visit www.ucpress.edu.
University of California Press
Berkeley and Los Angeles, California
University of California Press, Ltd.
London, England
© 2013 by The Regents of the University of California
Library of Congress Cataloging-in-Publication Data
Harrison, Susan (Susan Patricia)
Plant and animal endemism in California / Susan Harrison.
pages cm
Includes bibliographical references and index.
ISBN 978-0-520-27554-6 (cloth : alkaline paper)
eISBN 9780520954731
1. Endemic plants—California. 2. Endemic animals—California. 3. Endemic plants—Ecology—California. 4. Endemic animals—Ecology—California. 5. Endemic plants—Conservation—California. 6. Endemic animals—Conservation—California. I. Title.
QK149.H444 2013
581.9794—dc23
2012043370
Manufactured in the United States of America
22 21 20 19 18 17 16 15 14 13
10 9 8 7 6 5 4 3 2 1
The paper used in this publication meets the minimum requirements of ANSI/NISO Z39.48–1992 (R 2002) (Permanence of Paper).
Cover image: Sickle-leaved onion (Allium falcifolium), Oregon stonecrop (Sedum oreganum), and Siskiyou bitterroot (Lewisia cotyledon), members of three genera rich in Californian endemics.
Contents
Preface and Acknowledgments
Introduction
1.Biotic Uniqueness: An Overview
Large-Scale Patterns in Species Richness and Endemism
2.A Brief History of California
3.Plant Endemism in California: Patterns and Causes
Geography of Diversity and Endemism
Edaphic Endemism
New Evidence on the Evolution of Neoendemics
New Evidence on Paleoendemism
Californian Plant Endemism in a World Context
4.Animal Endemism in California
Cross-Taxonomic Comparisons
Mammals
Birds
Reptiles
Fish
Amphibians
Invertebrates
5.Conservation Challenges in California’s Endemic-Rich Landscape
Endangered Species Laws
Natural Community Conservation Planning
Conservation Easements
Conservation Banking
Advance Mitigation
Biodiversity Information
Systematic Conservation Planning
Marine and Aquatic Conservation
Climate Change Science and Policy
6.Synthesis and Conclusions
Appendix: Preliminary List of Plant Species Endemic to the California Floristic Province
Literature Cited
Index
Preface and Acknowledgments
Why write about endemism in California? Asked by a group of friendly but critical graduate students during a seminar visit, this question struck me as worth thinking about before beginning to write. Ecologists and evolutionists usually focus on broad, theory-driven questions. Isn’t it small-minded to focus on a place, let alone a place defined by human-drawn boundaries? And what about endemism, which the dictionary defines as “the condition of being native or restricted to a certain place”? Every species is endemic to somewhere, so what makes Californian endemism interesting?
My answers will be familiar to many readers, but perhaps not to all, as my experience with the out-of-state graduate students suggests. California is not just a political unit; uniquely among U.S. states, it is also more or less its own biogeographic region. More precisely, the state largely coincides with the California Floristic Province, one of only five regions in the world where the mediterranean climate is found. (This book considers endemism in the California Floristic Province wherever possible but concentrates largely on endemism in the state of California simply because of the greater availability of data at the state level.) The mediterranean biome worldwide is outstanding for its botanical uniqueness; it holds an estimated 20 percent of the world’s vascular plants in only 2 percent of the world’s land area. Some of this biome’s most distinctive groups of plants are thought to be evolving rapidly, and many classic studies of plant evolution and speciation have emerged from California. Finally, California has been the site of scientific and policy experiments aimed at the conservation of biological diversity, in part because traditional approaches to conservation are challenged by the sheer abundance and diffuse distribution of rare species in the state.
This book is motivated by the aim to learn new lessons at the interface of evolution, ecology, and conservation by examining California. Thus it focuses on analyzing patterns and addressing general questions, as outlined in the introduction. What this book does not do is explore the state’s rich natural history in any great depth; that has already been done well by many authors. Readers are directed, for example, to Elna Bakker’s An Island Called California, Allan Schoenherr’s Natural