Ecological Studies, Vol. 132

Analysis and Synthesis

Edited by

M.M. Caldwell, Logan, USA G. Heldmaier, Marburg, Germany O.L. Lange, Wiirzburg, Germany H.A. Mooney, Stanford, USA E.-D. Schulze, Bayreuth, Germany U. Sommer, Kiel, Germany Ecologica! Studies

Volumes published since 1992 are listed at the end of this book.

Springer Science+ Business Media, LLC Dieter Mueller-Dombois F. Raymond Fosberg (deceased)

Vegetation of the Tropical Pacific

With 521 illustrations, 436 in color

' Springer Dieter Mueller-Dombois F. Raymond Fosberg (deceased) Professor Emeritus Botanist Emeritus DepruUnentofBomny Museum of Natural History University of Hawai'i at Miinoa Smithsonian Institution Honolulu, Hawai'i 96822-2279 Washington, DC USA USA

Cover illustration: A map showing the Pacific tropical area covered in the text See Figure 1.1.

Library of Congress Cataloging-in-Publication Data Mueller-Dombois, Dieter, 1925- Vegetation of the tropical Pacific is1ands 1 Dieter Mueller Dombois, F. Raymond Fosberg. p. cm.--(Ecological studies ; 132) Includes bibliographical references (p. ) and index. ISBN 978-0-387-98313-4 1. Plant ecology--Oceania. 2. Plant communities--Oceania. 3. Phytogeography-Oceania. 1. Fosberg, F. Raymond (Francis Raymond), 1908-1993. Il. Title. m. Series: Ecologica! studies; V. 132. QK471.M84 1998 581.995-dc21 97-24026 ISBN 978-0-387-98313-4 ISBN 978-1-4419-8686-3 (eBook) DOI 10.1007/978-1-4419-8686-3

© 1998 Springer Science+Business Media New York Original1y published by Springer-Verlag New York, Inc. in 1998 All rights reserved. This work may not be trans1ated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use of general descriptive names, trade names, trademarks, etc., in this publication, even if the former are not especially identified, is not to be taken as a sign that such names, as understood by the Trade Marks and Merchandise Marks Act, may accordingly be used freely by anyone.

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987654321

ISSN 0070-8356 In Memoriam of F. Raymond Fosberg (1908-1993) who died during the book-writing effort

A special commemorative issue was published in the Atoll Research Bulletin no's 390-396 of February 1994 issued by the National Museum of Natural History, Smithsonian Institution, Washington, D.C., U.S.A. With the expressed wishes of my co-author, F. Raymond Fosberg, prior to his death in 1993

This book is dedicated to ANNETTE MUELLER-DOMBOIS

for her untiring assistance in the technical aspects of preparing this book for publication, and also for her considerable input through critical reading of the manuscript and, last not least, for her taking care of our everyday needs whenever we were together during writing sessions. D.M-D. Preface

This book is the result of a commitment made to Professor Heinrich Walter (University of Stuttgart-Hohenheim, Germany) in 1978 by Dr. F. Ray Fosberg and myself. Heinrich Walter initiated a book series entitled Vegetationsmono• graphien der einzelnen Grossriiume (Vegetation Monographs of the Major World Regions). Upon H. Walter's death in 1989, Professor Siegmar-W. Breckle (Uni• versity of Bielefeld) continued as editor of this monograph series. Professor Wal• ter's concept included nine world regions: Vol. I, North and Central America; Vol. II, ; Vol. III, Africa; Vol. IV, Australia; Vol. V, Tropical Asia; Vol. VI, East Asia; Vol. VII, Eastern Europe with North and Central Asia; Vol. VIII, Europe exclusive of Eastern Europe; and Vol. IX, the Pacific Islands. Vols. I, II, III, IV, and VII have since been published by Fischer Verlag, Stuttgart. Vol. VIII will be published concurrently as the last volume (in German) through Fischer Verlag. Vol. IX, this volume, is the second book in English (after Vol. IV) and the first to be published by Springer-Verlag. Vol. VI is currently in prepa• ration, and Vol. V is still in the planning stage. In 1979 Dr. Fosberg and I began to make tentative outlines for this book. His Pacific island work began in 1935, when he received his M.Sc. degree in botany from the University of Hawaii, based on work on the genus Gouldia (Rubiaceae ). His Ph.D. degree was obtained in 1939 from the University of Pennsylvania for a monographic revision of the Polynesian species of Hedyotis (Rubiaceae). Dur• ing WWII Dr. Fosberg was sent to to search for stands of Cinchona (Rubiaceae) as a source of quinine and related antimalarial alkaloids. In 1946 he participated as a botanist in a six-month "Economic Survey of Micronesia." This work initiated a continuing study of the flora and vegetation of the Pacific is• lands, which placed Ray Fosberg (FRF) at the focal point in studies of island ecosystems and conservation. In addition to Micronesia, FRF participated in sev• eral expeditions to and kept a lifelong interest in Pacific island vege• tation. In the course of his work, he published numerous papers, which are listed in a commemorative volume of the Atoll Research Bulletin (February 1994). With his longtime scientific associate, Dr. Marie-Helene Sachet, he assembled two big volumes of Island Bibliographies (Sachet and Fosberg 1955, 1971). Prof. H. Walter's concept for the Pacific vegetation book included Melanesia and New Zealand. It soon became apparent that New Zealand could not be treated in the same volume. However, Melanesia outside New Guinea was considered treatable in the context of one volume together with Micronesia, Polynesia, and the eastern Pacific islands. My task became to focus on Melanesia and the sub• tropical islands in the New Zealand region. During my sabbatical year in 1981,

vii viii Preface my wife, Annette Mueller-Dombois, and I began our field research in Fiji, where we stayed seven weeks. We traveled to New Caledonia, where we participated in field excursions arranged by ORSTOM for participants at the International Botanical Congress in Sydney. We thereafter spent some time in Papua New Guinea at the Wau Ecology Station and traveled from there through the Melane• sian Islands with two- to three-week stops in New Britain, Bougainville, the Solomon Islands, and Vanuatu. In 1988 I had a second opportunity to spend some time in Fiji and Vanuatu, and in 1992 I visited Lord Howe and Norfolk Islands. Other islands visited on research trips were Guam and the Galapagos. The objectives were in each case to meet with local experts and, wherever pos• sible, to arrange field excursions with them, and assemble literature and reports, many of which were only locally available. Numerous people helped in various ways, and they are mentioned in a separate acknowledgment. When we fmally began to write this book in 1986, the enormity of the task started to sink in. Our outline changed several times. The most difficult under• taking was to address this book at an appropriate level of generalization, that is, not to treat the vegetation too superficially yet not to get bogged down in too much detail. Moreover, we had to maintain the focus strictly on vegetation. An• other real problem was the unevenness of available information, which we tried to balance as much as possible. Still, it shows in our treatment, in which the ar• eas of greatest familiarity, Micronesia (FRF) and the Hawaiian Islands (DMD), received the most pages. The book-writing process was very staggered in the beginning, because both FRF and I had many other commitments. From 1986 to 1990, we could handle the book writing only as a low-priority task. FRF was able to write his book chapters only whenever he had a chance to come to Hawai'i from Washington, D.C., for two to three weeks at a time to stay in our house. For this we had to seek travel funds, which luckily became available to FRF at reasonably frequent intervals through his service tasks with the East-West Center, the National Trop• ical Botanic Garden, and the Bishop Museum and through work in botanical and ecological consultancy and biological conservation issues. In 1990 I retired from teaching to devote more time to the book-writing job. At the same time, I received an NSF Award for cooperative research in "Ecosys• tem Dynamics in Hawai'i" with Peter Vitousek, who was the PI for the Stanford segment of the NSF Award. This replaced my former teaching obligations for the next seven years. It forced the book-writing project into a second-level pri• ority but made it more challenging. FRF and I kept coming together about four times a year until February 1993, when his prostate cancer began to increase in severity. At that time he had his manuscripts on Micronesia and Polynesia quite well completed in first-draft form. He died that same year at his home in Falls Church, Virginia, in September. Be• fore his death he suggested that we dedicate this book to my wife, Annette, who took care of both of us whenever we came together for book-writing sessions at our home in Hawai'i. She not only provided for our everyday needs, she also did Preface 1x all the word processing of our handwritten manuscripts and learned to cope with the continuously changing computer technology in software as well as in hard• ware. Without her complete devotion to our writing task, this book would never have seen the light of day. Dieter Mueller-Dombois Kailua, Hawaii March 26, 1997 Acknowledgments

A very substantial contribution was made by Mark E. Nakamura (Center for In• structional Support, University of Hawai'i), who did all the line drawings on the computer with great skill and unlimited patience, following my numerous re• quests for modifications and corrections. A more supportive, cheerful, and pleas• ant computer graphics expert I could not have had. Gerry Ochikubo, our Botany Department administrative officer, provided essential support with great care in photocopying chapters and sending them out for review. I also must acknowledge, on behalf of my deceased coauthor, Ray Fosberg, the persons he frequently talked about as having given him strong professional support in this book-writing adventure. They included, in particular, Marie• Helene Sachet, Royce Oliver, Mary McCutcheon, Dan Nicolson, Lenore Smith, Sam Rainey, and David Stoddart. We received collegial input from the following reviewers of book chapters: Loren W. Kroenke, Tom Giambelluca, Tom Schroeder, Jim Fownes, and S.-W. Breckle (Introductory Chapter); Lani Stemmermann, Randy Thaman, Margie Falanruw (Chap. 1-V); Peter Green (Lord Howe, Norfolk); Margaret Christian (Norfolk Island section); Derral Herbst (Chap. V and the checklist of plant names); Mark Merlin (Chap. 1-V, VIII southern Cooks); Harley Manner (Chap. I-VII); Art Whistler, Bryce Decker (Chap. I-IX); Steven Montgomery (Chap. VI-VIII); Linda Pratt, Marta Orl6ci (Chap. IX); Tod Stuessy (Chap. X, Juan Fer• mindez Islands). I thank them all very much for their careful, time-consuming service and their valuable suggestions. I also must acknowledge the kind support that my wife and I received during our research travels in the Melanesian Islands in 1981. In Fijii we received ad• vice and logistic support from Thelma De Ausen Richmond, Neville Skinner, Harley Manner, John Gibbons, John Morrison, Trevor Greenwell, and William Clarke; with field trip guidance by David Hassall, Roger Beaver, and Peter Drys• dale; and expert help in plant identification in the field from Saula Vodanivulu. In New Caledonia we were guided by Philippe Morat, Monsieur Hoff, Jean• Marie Veillon, Evelyn Cayrol, J. Kasser, and other members of ORSTOM on a precongress foray, and by Gordon McPherson, Robert R. Thorne, Helen Brinon, Ben Stone, and Arthur Dahl. In Papua New Guinea we received support from Linsley Gressitt (Wau Ecology Station), Frans Arentz (Mt. Giluwe trip), Bruce Wilton, David Frodin, Bob Johns; in New Britain from Cyril Kondang, Nevil Haukroft, Peter Cannel, Tony Wespe, David Bimmingham; on Bougainville from Paul Hoffman (Forestry Dept.), Father Franz Herkenhoff (at Asitavi Mission), also there from Sisters Sylvia, Margaret, Agnes, and Thekla at the Girl's High School. In the Solomon Islands much logistic help was given by Martin Todd,

XI xii Acknowledgments

Lawrence Chase, Hugh Paia, and Keith Sanders; on field trips in Guadalcanal, we were guided by Geoff F. C. Dennis; on Malaita by Daniel Maelifaka (Burna village chief, who hosted us for a week), Henry Maelifaka (his brother, an agri• cultural teacher), and George Kakaiwate (Sulufo village chief). Trips to Georgia Island and Kolombangara were arranged in the Honiara Forestry Department by A. C. Orr and Enele Kwanairaro, and field assistance was given by Taswell Tahisau, Graham Chapman, and Peter E. Neil. On Kolombangara Silas Pitukola showed us T.C. Whitmore's plots on Shoulder Hill and accommodated us in the Poetete Forestry Cottage. In Vanuatu we were helped by Howard van Trease; at ORSTOM by Pierre Cabalon; on Malekula by Robin H. Deck and Robert M. Jordan (with N.Z. VSA), as well as Christian le Due and Jean Luc Michel/ow (with SATEC) in Norsup; in Port Vila by Martin Bennett, Judy Geappen, Dou• glas Malosa, and Barry Weightman; in Esperito Santo on field trips by Peter Branney and Rory Ricobert (ni-Vanuatu forester); by Martin Adams and Harold Stevens (ni-Vanuatu Agric. Extension Office); by Jean-Francois Mondain• Monval (agric. ext. officer); on Erromango by William Mette (ni-Vanuatu village chief) and Kilian Name/ (ni-Vanuatu forester). In New Zealand we were helped by Ross McQueen, who took us through North and South Islands' natural areas with expert guidance, Bob Brockie (field trip to Lower Hutt Exp. Area), Bruce Jeffries (Tongariro National Park superintendent), Udo Benecke, Eric J. Godley, John Wardle, and Peter Wardle (Christchurch). In 1988 I had a second opportunity to work in Fiji and Vanuatu. In Fiji I was accompanied on an islandwide field trip on Viti Levu again by Saula Vodanivulu; in Vanuatu on Efate and Malekula, by Joss Wheatley (Brit. overseas volunteer and ecology grad. student). We were hosted on Malekula by Chris Newell (plan• tation manager) and supplied with vehicle transportation and accompanied by Jim Williams (agr. meteorologist) on field trips. In 1992 I received much sup• port from John Pickard (Maquarie Univ., Sydney), PeterS. Green (expert on the flora of Lord Howe and Norfolk Is.), and Ian Hutton (expert naturalist), who ac• companied me on several field trips on Lord Howe (including a climb to Mt. Gower's summit). On Norfolk Island I received much help from Margaret Chris• tian (ANPWS), her husband, Ken Christian, from Beverly and Evan Owens (both expert naturalists and ardent conservationists), and expert field guidance from Naomi Gillet and Hugh Yorkston. Paul Stevenson (conservator, ANPWS) arranged for collecting permits and plant shipments. All of the above-mentioned persons greatly facilitated my fieldwork in the Melanesian Islands (1981, 1988), and on Lord Howe and Norfolk Islands (1992). I could not have succeeded without their generous help. A 1996 field trip through Guam to recheck FRF' s earlier vegetation map was facilitated with help from Harley Manner, Stephen Vaughn, Lynn Raulerson (University of Guam), and Heidi Hirsch (Anderson AFB). At this point, I also wish to acknowledge my three influential mentors, Hein• rich Walter (Stuttgart), Heinz Ellenberg (Gottingen), and Vladimir J. Krajina (British Columbia), who somehow "programmed" me for this task. Some further acknowledgment is also due to my former graduate students who contributed di• rectly and indirectly to this book. Acknowledgments xiii

This project would not have been possible without some fmancial support re• ceived from the East-West Center through Larry Hamilton's Pacific Island Pro• ject, from National Tropical Botanic Garden via its former director Bill Theobald, and from my NSF Award with Peter Vitousek, which provided support for ad• ditional fieldwork in Hawai'i. Finally, I am most grateful to the MacArthur Foundation for a substantial pub• lication grant to allow the inclusion of color slides and to lower the sales price of the book. Royalties received will be used for deserving graduate students and faculty of the Botany Department, University of Hawai'i, for research travel to continue studies on the vegetation ecology of the Pacific islands.

Dieter Mueller-Dombois Kailua, Hawaii March 28, 1997 Chapter Overview

Chapter I. INTRODUCTION (Pac. Is. map, p. 9) (DMD & FRF)

Chapter II. WESTERN MELANESIA (section map 1, p. 40) (DMD)

Chapter III. EASTERN MELANESIA (section map 2, p. 85) (DMD)

Chapter IV. THE SUBTROPICAL ISLANDS IN THE NEW ZEALAND REGION (section map 3, p. 163) (DMD)

Chapter V. MICRONESIA (section map 4, p. 200) (FRF)

Chapter VI. CENTRAL POLYNESIA (section map 5, p. 315) (FRF)

Chapter VII. WESTERN POLYNESIA (section map 6, p. 342) (FRF)

Chapter VIII. EASTERN POLYNESIA (section map 7, p. 386) (FRF)

Chapter IX. NORTHERN POLYNESIA: THE HAWAllAN ISLANDS (section map 8, p. 462) (DMD & FRF)

Chapter X. THE OCEANIC ISLANDS IN THE EASTERN PACIFIC (section maps 9, p. 579 & 10, p. 580) (DMD & FRF)

Chapter XL THE FUTURE OF ISLAND VEGETATION (DMD)

XV Contents

Dedication page, v Preface, vii Acknowledgments, xi

Chapter I. INTRODUCTION, 1 The Book Concept, 1 1. Focus, approach and objectives, 1 2. Vegetation treatment in a landscape perspective, 2 3. Floristic and vegetational plant geography, 3 Geographic Overview, 4 1. Island area included, 4 2. Phytogeographic questions, 7 3. Island subregions, 8 Geological Considerations, 11 1. Origin of the Pacific Ocean, 11 2. Plate tectonics and the Andesite Line, 12 3. Composite and shield volcanoes, 14 4. Types of islands, 16 5. Continental fragments and island arcs, 17 Some Floristic Relationships, 19 1. Australia, New Zealand, and New Caledonia, 19 2. New Caledonia and the Solomon Islands, 21 3. The role of New Guinea as floristic source area, 21 4. Vanuatu and Fiji, 22 5. Micronesia, Polynesia, and the Eastern Pacific, 23 Climate and Vegetation Patterns, 24 1. Temperature zones, 24 2. Rainfall zones, 26 3. Seasonality, 28 4. Tropical cyclones, 30 5. El Nifio and the Southern Oscillation, 31 6. Pacific-wide biomes, 34 Conclusions, 37

Chapter ll. WESTERN MELANESIA, 39 Introduction, 39 1. Regional geography, 39 2. Floristic aspects, 39

xvii xvm Contents

3. Climate diagrams, 41 4. Regional climate, 44 The Bismarck Archipelago and Other Islands Directly East of New Guinea, 45 Introduction, 45 1. Topographic and altitudinal zonation, 45 2. Soil substrates, 46 Regional Vegetation Types, 49 1. Coastal strand vegetation, 50 2. Mangrove forests, 50 3. Freshwater swamp forests and herbaceous wetlands, 51 4. Forest on limestone, 53 5. Lowland rain forest on acid soils, 53 6. Montane rain forest, 54 7. Other vegetation types, 55 Bougainville and Buka Island, 57 Introduction, 57 1. Climate and topography, 57 2. Soil substrates, 58 Principal Vegetation Types, 58 1. Coastal strand vegetation, 59 2. Mangrove forests, 59 3. Freshwater swamp forest and herbaceous wetland vegetation, 59 4. Floodplain forest, 60 5. Lowland rain forest on well-drained soils, 60 6. Forest on ancient limestone, 61 7. Submontane rain forest, 61 8. Montane forest and scrub, 61 9. Vegetation on recent volcanic surfaces, 62 10. Anthropogenically modified and secondary vegetation, 62 Summary of Vegetation Patterns, 63 The Solomon Islands, 65 Introduction, 65 1. Climate and weather disturbances, 66 2. Topography, 67 3. Geology and soils, 67 4. Human population, 68 5. Phytogeographic aspects, 69 Regional Vegetation Types, 70 1. Coastal strand vegetation, 70 2. Mangrove forest, 70 3. Freshwater swamp forests and herbaceous wetland vegetation, 71 4. Lowland rain forest on well-drained soil, 72 5. Low-diversity rain forests, 74 6. Seasonally dry forest and grassland, 75 Contents xix

7. Montane rain forest, 77 8. Anthropogenically modified vegetation, 78 Vegetation of the Outer Islands, 79 1. Bellona, 79 2. Rennell, 81 3. Ontong Java, 81 Conclusions, 83

Chapter ill. EASTERN MELANESIA, 84 Introduction, 84 1. Regional geography, 84 2. Regional geology, 86 3. Regional climate, 86 Treatment of the Vegetation, 88 The Santa Cruz Islands, 89 Kauri Dynamics in the Santa Cruz Islands, 90 Vanuatu, 93 Introduction, 93 1. Climate, 94 2. Geology, 94 3. Soils, 95 Regional Vegetation Types, 97 1. Lowland rain forest, 98 2. Montane cloud forest and related vegetation, 101 3. Seasonal forest, scrub, and grassland, 101 4. Vegetation on new volcanic surfaces, 103 5. Coastal vegetation, including mangroves, 103 6. Secondary and cultivated woody vegetation, 104 Vegetation of the Northern Outlier and Central Islands, 105 1. Torres Islands, 105 2. Banks Islands, 106 3. Aoba, Ambrym, Epi, and the Shepherd Islands, 106 Regeneration Dynamics of the Kauri Forests in South Vanuatu, 107 Fiji, 108 Introduction, 108 1. Climate, 109 2. Geology, 111 3. Origin of the Flora, 112 Principal Vegetation Types, 113 1. Lowland rain forest, 114 2. Upland rain forest, 119 3. Cloud forest, 121 4. Dry forest, 122 5. Talasiqa vegetation, 123 6. Freshwater wetland vegetation, 127 xx Contents

7. Mangrove forest and scrub, 129 8. Coastal strand vegetation, 130 Vegetation on Smaller Islands, 132 1. Vanua Balavu and Lakeba, 132 2. Kabara, 135 3. Nairai and Batiki, 135 New Caledonia, 136 Introduction, 136 1. Climate, 137 2. Geological origin, 139 3. Phytogeographic relationships, 142 Principal Vegetation Types, 144 1. Lowland (mesic) rain forest, 145 2. Montane rain and cloud forest, 147 3. Forest on limestone, 149 4. Dry sclerophyll forest, 149 5. Savanna, 150 6. Maquis (scrub) vegetation, 151 7. Lowland swamp vegetation, 156 8. Mangrove and strand vegetation including littoral forest, 157 9. Modified vegetation, 158 Conclusions, 161

Chapter N. THE SUBTROPICAL ISLANDS IN THE NEW ZEALAND REGION, 162 Introduction, 162 1. Regional overview, 162 2. Regional climate, 162 Lord Howe Island, 165 1. Geography, 165 2. Climate, 165 3. Geology, 167 4. Soils, 168 5. History of settlement, 168 6. Phytogeographic relationships, 169 Vegetation, 169 1. Lowland subtropical rain forest, 170 2. Submontane rain forest, 173 3. Cloud forest and scrub, 173 4. Lowland swamp forest, mangrove, and seagrass vegetation, 174 5. Coastal scrub and cliff vegetation, 174 6. Inland scrub and herbland, 176 7. Off-shore island vegetation, 176 8. Shoreline and beach vegetation, 177 9. Disturbed vegetation, 178 Contents xxi

10. Summary of vegetation patterns, 179 11. Canopy dieback, 181 Norfolk Island, 182 1. Geography, 182 2. Climate, 182 3. Geology, 182 4. Soils, 184 5. Land use, 184 6. Vegetation, 185 7. Distribution patterns, 187 8. Phytogeographic relationships, 191 9. Nepean and Philip Islands, 192 10. Araucaria decline and dieback, 193 The Kermadec Islands, 194 1. Geography, climate, and geology, 194 2. Vegetation, 194 Conclusions, 197

Chapter V. MICRONESIA, 199 Introduction, 199 1. Regional geography and climate, 199 2. Substrates and soil-parent materials, 201 3. Treatment of vegetation, 204 Regional Vegetation Types, 205 1. Mangrove vegetation, 205 2. Strand Vegetation, 207 3. Vegetation on coral atolls and low coral islands, 211 4. Vegetation on raised coral or elevated limestone, 216 5. Vegetation on coastal plains, including swamp forests, 220 6. Lowland rain forest, 223 7. Montane rain forest and cloud forest, 225 8. Dwarf vegetation on open crests, 227 9. Vegetation on rough lava flows, 228 10. "Savanna" or grassland vegetation, 228 The Bonin and Volcano Islands, 234 1. The Bonin (Ogasawara) Islands, 234 2. The Volcano (Kazan) Islands, 238 Marcus Island, 240 The Marianas, 241 1. Introduction, 241 2. Past vegetation studies, 241 3. Human influences on the vegetation, 242 4. Subregional differences, 243 The Northern Marianas, 243 1. Uracas, 244 xxii Contents

2. Maug, 244 3. Asuncion, 245 4. Agrihan, 247 5. Pagan, 248 6. Alamagan, 250 7. Guguan, 251 8. Sarigan, 251 9. Anatahan, 252 10. Concluding summary, 252 The Southern Marianas, 254 1. Physiography, 254 2. Vegetation, 254 3. Farallon de Medinilla, 255 4. Saipan, 256 5. Tinian, 259 6. Aguigan, 264 7. Rota, 265 8. Guam, 269 The Caroline Islands, 275 1. Regional geography, 275 2. The vegetation in general, 276 3. The Belau Islands (Palau), 277 4. Yap and Fais, 284 5. Chuuk Almost-Atoll, 286 6. Pohnpei (Ponape ), 288 7. Kosrae (Kusaie), 291 8. The Atolls of the Caroline Islands, 292 Nauru and Banaba, 293 Wake Island, 296 The Marshall Islands, 297 1. Introduction, 297 2. Regional vegetation, 298 3. Taongi Atoll, 303 4. Bikar Atoll, 305 The Gilbert Islands (Kiribati), 306 1. Geography and flora, 306 2. Climate and substrate, 307 3. Vegetation, 308 Conclusions, 309 1. A brief review, 309 2. Biodiversity in atoll vegetation: what are the determinants?, 310

Chapter VI. CENTRAL POLYNESIA, 314 Introduction, 314 1. Regional geography, 314 2. Regional climate, 315 Contents xxiii

Vegetation, 317 1. Regional overview, 317 2. Johnston Island, 318 3. The Phoenix Islands, 318 4. The Line Islands, 323 5. Pacific Equatorial Sporades: Howland, Baker, Jarvis, Malden, and Starbuck, 327 6. Central Pacific moist-zone atolls, 328 Conclusions, 336

Chapter Vll. WESTERN POLYNESIA, 341 Introduction, 341 1. Regional geography and geology, 341 2. Regional climate, 342 3. Treatment of vegetation, 344 Tonga,345 Introduction, 345 Vegetation, 347 1. Mangrove vegetation, 347 2. Beach vegetation, 348 3. Vegetation of rocky coasts, 348 4. Primary rain forest, 348 5. Secondary forest, 348 6. Fern- and grassland, 349 Tongatapu, 349 1. Mangrove swamps, 349 2. Coastal swamp forest, 349 3. Coastal marsh, 350 4. Littoral forest, 350 5. Coastal savanna, 350 6. Tropical lowland rain forest, 350 7. Secondary or cultivated vegetation, 351 8. Reproductive capacity of Tongatapu's native rain forest remnants, 351 'Eua Island, 352 1. Introduction, 352 2. Vegetation, 352 3. Reanalysis of 'Eua's forest communities, 355 Western Tier of Young Volcanic Islands, 357 1. Niuafo'ou, 357 2. Late, 358 Samoa, 360 Introduction, 360 Vegetation, 361 1. Littoral vegetation, 362 2. Wetland vegetation, 363 xxiv Contents

3. Lowland rain forest 364 4. Montane rain forest, 368 5. Cloud forest and scrub, 368 6. Vegetation on recent volcanic surfaces, 372 7. Modified vegetation, 372 Forest Dynamics in Samoa, 375 Rotuma, 376 Home (Hoom, Hom or Wallis) Islands, 378 Introduction, 378 Vegetation, 378 1. Mangrove swamps, 378 2. Psammophilous littoral vegetation, 379 3. Rupicolous littoral forest, 379 4. Dense evergreen forest, 380 5. Montane rain and cloud forest, 381 6. Freshwater wetlands, 381 7. Secondary vegetation, 381 Niue Island, 381 Introduction, 381 Vegetation, 382 1. Coastal forest, 382 2. Plateau forest, 382 3. Femland, 383 Conclusions, 383

Chapter Vlll. EASTERN POLYNESIA, 385 Introduction, 385 1. Regional geography and geology, 385 2. Regional climate, 387 3. Regional vegetation, 387 The Cook Islands, 390 Geography, 390 1. Rarotonga, 392 2. Aitutaki, 394 3. Miti'aro, Atiu, Ma'uke and Mangaia, 395 4. Palmerston, Manuae, and Takutea Islands, 400 The Austral Islands, 400 Introduction, 400 Vegetation, 401 1. Marotiri Rocks, 402 2. Rapa, 402 3. Raivavae, 404 4. Tubuai, 405 5. Rurutu, 406 6. Rimatara, 406 7. Maria Atoll, 406 Contents xxv

The Society Islands, 407 Introduction, 407 1. Geography and climate, 407 2. Geology and hydrology, 409 Vegetation conditions, 409 1. Floristics, 409 2. Original vegetation, 410 3. Polynesian influences, 411 4. European influences, 412 Vegetation patterns, 413 1. Mehetia, 413 2. Tahiti, 414 3. Moorea, 418 4. Maiao (Tubuai-Manu), 420 5. Huahine, 420 6. Raiatea, 422 7. Tahaa, 426 8. Bora Bora, 428 9. Maupiti 429 10. Society Atolls, 429 The French system of classification, 430 Conclusions, 431 The Tuamotu Archipelago, 433 Introduction, 433 1. Tuamotu Atolls, 434 2. Makatea Island, 437 3. The Gambier Islands (Mangarewa), 438 4. Pitcairn Island, 440 5. Oeno Island, 441 6. Henderson Island, 441 7. Ducie Atoll, 443 and Sala y Gomez, 443 1. Easter Island (Rapa Nui or Isla de Pasqua), 443 2. Sala y Gomez, 444 The Marquesas, 444 Introduction, 444 1. Geography, 444 2. Climate, 446 3. Prior vegetation treatments, 446 Vegetation patterns, 447 1. Xerotropicallowland zone, 447 2. Pluviotropical and transitional zone, 448 3. Strand zone, 448 4. Dry seaward slope vegetation, 449 5. Mesophytic inland vegetation, 449 6. Cultivated forest remnants, 451 xxvi Contents

7. Montane mesic rain forest, 451 8. Montane rain and cloud forest mosaic, 451 Vegetation of the Individual Marquesan Islands, 452 1. Hiva Oa Island, 452 2. Tahuata Island, 453 3. Fatu Hiva Island, 453 4. Mohotani Island, 454 5. Fatu Huku Island, 454 6. Nuku Hiva Island, 454 7. Ua Pou Island, 456 8. Ua Huka Island, 456 9. Motu Iti (Fatuiti), 457 10. Eiao Island, 457 11. Hatutaa Island, 458 12. Cotar (Motu One), 458 Summary and Conclusions, 459

Chapter IX. NORTHERN POLYNESIA: THE HAWAIIAN ISLANDS, 461 Introduction, 461 1. Geography, 461 2. Climate, 464 3. Climatic disturbances, 466 4. Island chronosequence and geomorphology, 469 5. Soil substrates, 472 6. Origin of the Hawaiian flora, 474 7. Treatment of vegetation, 477 Vegetation of the larger Hawaiian Islands, 478 (Hawai'i, Maui, Lana'i, Moloka'i, O'ahu, Kaua'i) 1. Coastal strand, marsh, mangrove and cliff vegetation, 478 2. Lowland dry forest, savanna, scrub and grassland, 486 3. Lowland to upper montane seasonal forests, 502 4. Lowland to upper montane rain forests, including femlands, 511 5. Montane cloud forests, 521 6. Montane bogs, 527 7. High-altitude vegetation, 532 8. Deserts and vegetation on new volcanic surfaces, 541 9. Cultivated vegetation, 547 Vegetation of the Smaller Hawaiian Islands, 555 1. The dry volcanic-substrate islands, 556 (Kaho'olawe, Ni'ihau, Nihoa and Necker) 2. The Hawaiian atolls and coral reef islands, 566 (French Frigate Shoals, Maro Reef, Laysan Island, Lisianski, Pearl and Hermes Reef, Midway, and Kure Atoll) Conclusion: Dynamics in the Hawaiian Vegetation, 572 1. Vegetation dynamics with rain forest dieback, a naturally induced process, 573 Contents xxvii

2. Vegetation dynamics with alien species, a human-induced process, 575

Chapter X. THE OCEANIC ISLANDS IN THE EASTERN PACIFIC, 578 Introduction, 578 The Revillagigedos Islands, 578 1. Introduction, 578 2. San Benedicta, 581 3. Socorro, 581 4. , 583 5. , 583 Cocos and Malpelo, 583 1. , 584 2. , 585 , 585 The Galapagos Islands, 587 1. Introduction, 587 2. Climate, 589 3. Vegetation, 590 4. Principal vegetation zones, 591 5. Bogs, lava flow vegetation, and other communities, 595 6. Summary of spatial vegetation patterns, 596 7. Vegetation dynamics in the moist zone, 600 The , 604 1. Introduction, 604 2. San Ambrosio, 604 3. San Felix, 607 Juan Fernandez, 609 1. Introduction, 609 2. (Masatierra), 611 3. Santa Clara Island, 614 4. (Masafuera), 614 5. Vegetation summary and profile, 616 Summary and Conclusions, 618

Chapter XI. THE FUTURE OF ISLAND VEGETATION, 620 1. Introduction, 620 2. The human factor, 621 3. Fosberg's entropy concept, 627 4. The Hawai'i mp concept, 628 5. Conceptional aspects arising from this book, 630 6. Conclusion, 640

References, 642 Checklist of Plant Names, 676 Index, 713