Red Ape in the Red – Abundance, Threats and Conservation
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Red Ape in the Red – Abundance, Threats and Conservation Dissertation zur Erlangung des Doktorgrades der Naturwissenschaften (Dr. rer. nat.) der Naturwissenschaftlichen Fakultät I – Biowissenschaften – der Martin-Luther-Universität Halle-Wittenberg, vorgelegt von Frau Maria Voigt, M.Sc. geboren am 07.09.1988 in San Diego, USA Datum der Verteidigung: 21.10.2019 Gutachter: Professor Henrique M. Pereira (Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) und Martin-Luther Universität Halle- Wittenberg Dr Hjalmar S. Kühl (Max Planck Institut für evolutionäre Anthropologie und Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv)) Professor Nina Farwig (Philipps Universität Marburg) To Mom, Dad and Robert for everything! Copyright notice: Reprint of the presented material requires the authors' permissions. Copyright is with the authors. Table of Contents SUMMARY 1 CHAPTER 1 3 INTRODUCTION 3 Biodiversity changes in the tropics...........................................................................3 Why are orangutans special?.....................................................................................3 Orangutans on Borneo – past and present distribution.............................................4 Drivers of orangutan decline.....................................................................................5 Orangutan conservation and impediments................................................................6 Objectives of the thesis.............................................................................................7 CHAPTER 2 15 GLOBAL DEMAND FOR NATURAL RESOURCES ELIMINATED MORE THAN 100,000 BORNEAN ORANGUTANS 15 Summary.................................................................................................................18 RESULTS................................................................................................................19 Bornean Orangutan Field Survey Data...............................................................19 Estimating Change in Bornean Orangutan Density Distribution........................19 Linking Remotely Sensed Resource Use and Density Distribution...................22 DISCUSSION.........................................................................................................24 STAR METHODS..................................................................................................33 KEY RESOURCES TABLE...................................................................................33 METHOD DETAILS..............................................................................................34 Study area and orangutan data............................................................................34 Predictor variables of orangutan abundance.......................................................35 Future orangutan abundance...............................................................................37 QUANTIFICATION AND STATISTICAL ANALYSIS........................................37 Calculating model offset.....................................................................................37 Effective strip width............................................................................................37 Estimation of nest decay rate and extrapolation.................................................38 Model structure and multi-model inference........................................................39 Parametric bootstrapping to estimate confidence limits.....................................40 Spatial overlap of orangutan density distribution and resource use....................40 CHAPTER 3 43 DEFORESTATION PROJECTIONS IMPLY RANGE-WIDE POPULATION DECLINE FOR CRITICALLY ENDANGERED BORNEAN ORANGUTANS 43 INTRODUCTION..................................................................................................45 MATERIAL AND METHODS..............................................................................47 Identifying main deforestation drivers on Borneo..............................................47 Deforestation model framework.........................................................................47 Simulations.........................................................................................................48 Validation and analysis........................................................................................48 Priority areas for orangutan conservation based on deforestation projections....48 RESULTS................................................................................................................49 Deforestation model for Borneo.........................................................................49 Validation............................................................................................................49 Spatial deforestation projections.........................................................................49 Probability of deforestation projections on Borneo over time............................51 Projected threat to orangutan populations within states......................................52 Projected threat to orangutan populations within land-use and management categories............................................................................................................53 DISCUSSION.........................................................................................................55 Drivers of deforestation on Borneo.....................................................................55 Observed and projected deforestation.................................................................55 Projected deforestation and orangutans in PAs and logging concessions...........56 Projected deforestation and orangutans in plantations and other non-protected areas....................................................................................................................57 Considering regrowth of forests..........................................................................58 Potential to expand the modeling approach to other species..............................58 Killing as an additional driver of orangutan loss................................................58 Implications for biodiversity conservation.........................................................59 CHAPTER 4 67 ORANGUTAN POPULATIONS ARE CERTAINLY NOT INCREASING IN THE WILD 67 CHAPTER 5 73 CHALLENGES AND OPPORTUNITIES FOR MONITORING A CHARISMATIC SPECIES IN THE TROPICS – INTEGRATING DATA AND STAKEHOLDERS 73 INTRODUCTION..................................................................................................75 BORNEAN ORANGUTANS - STATUS, TREND AND THREATS....................77 Population status and trend.....................................................................................77 Threats to orangutan populations........................................................................77 MONITORING.......................................................................................................78 Variables of interest and methods of observation...............................................78 Sampling design..................................................................................................80 MODELS FOR SPECIES MONITORING............................................................82 Species distribution models................................................................................82 Integrated population models..............................................................................83 Models to improve monitoring...........................................................................84 REPORTING..........................................................................................................84 Monitoring data for use.......................................................................................84 Taxa-specific databases.......................................................................................85 Tools for reporting..............................................................................................86 Integration of stakeholders..................................................................................87 CONCLUSION.......................................................................................................89 CHAPTER 6 97 SYNTHESIS 97 Estimating the density distribution of species..........................................................97 Importance of communication and integration.........................................................98 Conservation and global socio-political climate.......................................................99 Is there still hope?...................................................................................................100 APPENDIX I Appendix – Chapter 2.....................................................................................................................i Appendix – Chapter 3....................................................................................................................vi APPENDIX S1........................................................................................................vi Further description of source data and deforestation model for Borneo..................vi Spatial layers of deforestation drivers..................................................................vi Deforestation model and calibration...................................................................vii Simulations........................................................................................................viii