Restoring the Oceanic Island Ecosystem (eBook)

Restoring the Oceanic Island Ecosystem 1
Title Page 2
Copyright 3
Preface 4
Acknowledgments 6
Contents 7
Part I: The Bonin Islands 10
Chapter 1 11
What’s the Bonin Islands? 11
1.1 Location and Geography 11
1.2 Fauna and Flora 11
1.3 History of Human Disturbances 12
References 14
Part II: Impacts of Invasive Alien Species 16
Chapter 2 17
Impacts of Invasive Alien Species on Native Ecosystems on the Bonin Islands 17
2.1 Background 17
2.2 Flatworms 17
2.3 Black Rats 18
2.4 Feral Cats 18
2.5 Green Anoles 18
2.6 Feral Goats 19
2.7 Bischofia javanica 19
2.8 Leucaena leucocephala 19
References 19
Chapter 3 21
Chapter 3The cause of mollusk decline on the Ogasawara Islands 21
Introduction 21
Methods and study area 22
Study island and snails 22
Population density 22
Mortality 23
Predators 24
Distribution of predators 24
Results 25
Population density 25
Mortality 27
Predators 27
Distribution of predators 28
Discussion 28
Acknowledgements 30
References 30
Chapter 4 32
Rapid decline of endemic snails in the Ogasawara Islands, Western Pacific Ocean 32
Introduction 32
Materials and Methods 33
Results 33
Distrigution of Mandarina (Chichi-jima Is) 33
Distribution of Mandarina chichijimana (Chi chijimaIs.) 34
Distribution of Mandarina polita (Hahajima Is.) 34
Distribution of Mandarina aureola (Hahajima Is.) 34
Distribution of Mandarinaponderosa (Hahajima Is.) 34
Distribution of Platydemus manokwari 36
Discussion 36
Acknowledgements 37
References 37
Chapter 5 39
Food habit of Platydemus manokwari De Beauchamp, 1962 (Tricladida: Terricola: Rhynchodemidae), known as a predatory flatworm of land snails in the Ogasawara (Bonin) Islands, Japan 39
Introduction 39
Materials and Methods 40
Distribution and field observation of the food habit of P. manokwari. 40
Results 40
Distribution and field observation of the food habit of P. manokwari 40
Feeding tests 41
Discussion 41
Ackowledgements 43
References 44
Chapter 6 45
High Predation Pressure by an Introduced Flatworm on Land Snails on the Oceanic Ogasawara Islands1 45
Acknowledgments 47
Literature Cited 47
Chapter 7 49
Potential impacts of the invasive flatworm Platydemus manokwari on arboreal snails 49
Introduction 49
Materials and methods 50
Study site and species 50
Field experiment 50
Data analysis 51
Results 52
Discussion 53
References 53
Chapter 8 55
Impacts of Predation by the Invasive Black Rat Rattus rattus on the Bulwer’s Petrel Bulweria bulwerii in the Bonin Islands, Japan 55
8.1 Introduction 55
8.2 Mortality on Higashijima 56
8.3 Post Eradication Status 57
8.4 Situation on the Other Islands 57
8.5 Conclusions 58
References 59
Chapter 9 60
Morphological and ecological shifts in a land snail caused by the impact of an introduced predator 60
Introduction 60
Materials and methods 61
Estimation of predation pressure by Rattus rattus 61
Morphological analysis 61
Analysis of habitat use 62
Results 62
Change in predation pressure 62
Morphological change 62
Shift in habitat use 63
Discussion 63
References 66
Chapter 10 68
Bird predation by domestic cats on Hahajima Island, BoninIslands, Japan 68
References 69
Chapter 11 70
Feral cat predation on seabirds on Hahajima, the BoninIslands, Southern Japan 70
Methods 70
Results 70
Discussion 71
Acknowledgements 72
References 72
Chapter 12 74
High population densities of an exotic lizard, Anolis carolinensis and its possible role as a pollinator in the Ogasawara Islands. 74
Introduction 74
Methods and study area 75
Results 75
Discussion 76
Aknowledgement 76
References 77
Chapter 13 78
Why have endemic pollinators declined on the Ogasawara Islands? 78
Introduction 78
Methods 79
Four hypotheses 79
Honeybee competition hypothesis 79
Forest decline hypothesis 80
Agricultural insecticides hypothesis 80
Anole predation hypothesis 80
Test of hypotheses 81
Results and discussion 81
Perspective for Conservation 84
References 84
Chapter 14 87
Vegetation changes between 1978, 1991 and 2003 in the Nakoudojima island that had been disturbed by feral goats 87
Introduction 87
Methods 88
Results 88
Discussion 91
Acknowledgment 92
References 92
Chapter 15 94
Seed and seedling demography of invasive and native trees of subtropical Pacific islands 94
Introduction 94
Methods 95
Study site 95
Seed fall and seedling emergence census 95
Seed removal experiments 96
Estimation of soil seed bank 96
Data analyses 96
Results 97
Annual variation in seed production 97
Seed predation 97
Distribution of seed bank in the soil profile 97
Seed longevity in forest soil 98
Seedling emergence and survival 98
Discussion 100
References 101
Chapter 16 104
Effects of an alien shrub species, Leucaena leucocephala, on establishment of native mid-successional tree species after disturbance in the national park in the Chichijima island, a subtropical oceanic island 104
Introduction 104
Materials and Methods 105
Plant species 105
Study site 105
Field experiments 105
Data analysis 106
Results 106
Field experiments 108
Discussion 108
References 109
Part III: Countermeasure Against Invasive Species 112
Chapter 17 113
Management of Invasive Alien Species in the Bonin Islands 113
17.1 Management of Invasive Alien Species in the Bonin Islands 113
17.2 Strategy and Tactics Toward Eradication of Selected Alien Species 114
17.2.1 Flatworm 114
17.2.2 Green Anole 114
17.2.3 Black Rat 115
17.2.4 Bischofia javanica 115
References 116
Chapter 18 117
Species Diversity and Conservation of Mandarina, an Endemic Land Snail of the Ogasawara Islands 117
1. Introduction 117
2, Divergences in Habitat Preference and Morphology 118
3. Parallel Adaptive Radiation of Mandarina in the Ogasawara Islands 119
4. Interspecific Hybridization 121
5. Endangerment of Mandarina and its Conservation 122
6. Conclusion 124
Acknowledgments 124
References 124
Chapter 19 126
Hot water tolerance of soil animals: utility of hot water immersion in preventing invasions of alien soil animals 126
Introduction 126
Materials And Methods 127
Results 128
Discussion 128
Acknowledgements 129
References 129
Chapter 20 132
Endemic Insects in the Ogasawara Islands: Negative Impacts of Alien Species and a Potential Mitigation Strategy 132
20.1 Introduction 132
20.2 Factors of the Decline 132
20.3 The Impact of Green Anoles 133
20.3.1 Extinction of Endemic Species 133
20.3.2 Radical Changes in Ecosystems 133
20.3.3 Various Alien Species and Endemic Insects 133
20.4 Mitigating Impacts 134
20.5 Development of Techniques to Manage Alien Species 135
20.6 Future Developments 135
References 136
Chapter 21 137
A decrease in endemic odonates in the Ogasawara Islands, Japan 137
Introduction 137
Materials and methods 138
Results 139
Discussion 140
Acknowledgements 141
References 141
Chapter 22 143
Ecology and Control of the Green Anole ( Anolis carolinensis ), an Invasive Alien Species on the Ogasawara Islands 143
22.1 Introduction 143
22.2 Characteristics of the Green Anole 143
22.2.1 Genus Anolis 143
22.2.2 The Green Anole as an Alien Species 144
22.3 Ecology and Population Control of Anoles on Ogasawara 144
22.3.1 Introduction and Expansion of Population Range 144
22.3.2 Population Density 144
22.3.3 Growth and Maturation 145
22.3.4 Feeding Behavior and Its Impact on the Ecosystem 145
22.3.5 Population Structure 146
22.3.6 Basic Concepts of Population Control 146
22.3.6.1 Prevention of Population Dispersal 147
22.3.6.2 Area-Specific Control 147
22.3.6.3 Establishing a Method for Capture 147
22.3.6.4 Regional Characteristics 147
22.3.6.5 Adaptive Management to Monitoring Data 147
22.4 Ongoing Projects on the Ogasawara Islands 147
22.4.1 Development of Methods for Regional Eradication of Anoles 147
22.4.1.1 Capturing Methods 147
22.4.1.2 Exclusion Barriers 148
22.4.2 Capturing Anoles in the Vicinity of the Harbor to Prevent Dispersal to Neighboring Islands 149
22.4.3 Preventing Local Extinction of Insect Species Endemic to the Ogasawara Islands 149
22.5 Epilogue 150
References 150
Chapter 23 151
Eradication and Ecosystem Impacts of Rats in the Ogasawara Islands 151
23.1 Introduction 151
23.2 Effects of Alien Rats on Ecosystems 151
23.3 Distribution of Alien Rats in the Ogasawara Islands 153
23.4 Is Rat Eradication Possible? Examples from Around The World 153
23.5 Rat Eradication Methods 154
23.6 Rat Eradication in the Ogasawara Islands: Nishijima 155
23.7 Future Control of Rats in the Ogasawara Islands 156
References 157
Chapter 24 158
Eradication of the Invasive Tree Species Bischofia javanicaand Restoration of Native Forests on the Ogasawara Islands 158
24.1 Introduction 158
24.2 Assessing the Expansion of B. javanica Distribution on the Ogasawara Islands 159
24.2.1 Introduction of B. javanica 159
24.2.2 Vegetation Types Colonized by B. javanica 159
24.2.3 Distribution Map of B. javanica Based on Aerial Photographs 159
24.2.4 B. javanica Occurrence Probability and Evaluation of Colonization Risk 162
24.3 Ecology of B. javanica and Impact of Its Reproduction 163
24.3.1 Reasons for Enhanced B. javanica Population Growth 163
24.3.2 Impact of B. javanica Expansion 164
24.4 Recovery of Native Tree Species After Clear-Cutting in a B. javanica Forest 164
24.5 Eradication of B. javanica on Hahajima by Girdling and Cutting 165
24.6 Herbicidal Eradication of B. javanica on Ototojima 165
24.7 Management System for Whole-Island Eradication of B. javanica 166
References 167
Chapter 25 169
Predicting future invasion of an invasive alien tree in a Japanese oceanic island by process-based statistical models using recent distribution maps 169
Introduction 169
Materials and methods 170
Study site 170
Distribution maps 172
Site environments and distance from seed sources 172
Models 172
Habitat suitability model 172
Colonization kernel 172
Simultaneous model with simple logistic regression (SSLR) 173
Simultaneous model with an explicit dispersal kernel (SEDK) 173
Model estimation and comparison 174
Map of the potential habitat distribution and forth cominginvasion threat 174
Results 175
Discussion 175
References 178
Chapter 26 180
Beetle responses to artificial gaps in an oceanic island forest: implications for invasive tree management to conserve endemic species diversity 180
Introduction 181
Materials and methods 184
Study site 184
Insects 184
Methods 185
Data analyses 186
Results 186
Beetle endemism 186
Beetle responses to artificial gaps 187
Beetle species composition 191
Discussion 194
Seasonal differences in beetle abundance and diversity 194
Beetle responses to artificial gaps 194
Implications for invasive tree management for endemic insect conservation 195
References 196
Part IV:Implications for Island Ecosystem Management 198
Reconstruction of the Ecosystem in the Bonin Islands 199
27.1 Eradication Efforts 199
27.2 Cat Control 199
27.3 Development of Control Techniques 200
27.4 Prevention of Range Expansion 200
27.5 Prioritization 200
27.6 Development of Conservation Methods 200
27.7 Monitoring Systems 201
27.8 Interspecific Relationships Between Natives and Aliens 201
27.9 Conclusion 202
References 202
List of Recent Publications Related to this Book 204
Subject Index 206