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MARINE ECOSYSTEM RESTORATION WITH A FOCUS ON CORAL REEF ECOSYSTEMS by DIVYA ALICE VARKEY B.F.Sc., Kerala Agricultural University, 2003 M.F.Sc., Central Institute of Fisheries Education, 2005 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in THE FACULTY OF GRADUATE STUDIES (Resource Management and Environmental Studies) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) November 2010 © Divya Alice Varkey Abstract The declines of fish populations in ecosystems around the globe have triggered considerable interest in marine ecosystem restoration. In addition to focusing on individual fish populations, there is increased emphasis on understanding inter-species interactions and on understanding the human relationships with the ecosystems. My thesis approaches marine restoration from (a) practical aspects of considering multispecies interactions in the ecosystem (Ecopath with Ecosim models), estimating unreported and illegal catches (influence tables) and policy that considers the concerns of multiple stakeholders (Bayesian influence diagram modeling); (b) theoretical aspects of carrying capacity and fish life history analyzed using life history parameters (Population dynamics modeling). I begin my thesis by exploring the technological, socio-economic, and political history of Raja Ampat in Eastern Indonesia (my geographical focus) to understand resource management challenges and to calculate the trends in relative misreporting of fisheries catch. The unreported fish catch exceeds the reported fish catch by a factor of 1.5. My next chapter explores the ecological benefits of establishing marine protected areas for coral reef ecosystems in Raja Ampat using Ecopath, Ecosim and Ecospace models. I estimate an ideal minimum size of no-take areas— the size of no-take area at which the biomass density of reef fish reached an asymptote—to be 16 to 25 km2. Analysis of biomass density of reef fish in MPAs led to questions about ecosystem carrying capacity. To explore carrying capacity, I reconstruct ancient snapper population biomass using archaeological data obtained from fish middens using equilibrium age structure model. The results show that the ancient snapper population was about 2 to 4 times higher than the modern population biomass. To model the differing utilities of different stakeholders, in the next chapter, I develop a bayesian influence diagram model. The results indicate that restricting net fisheries and implementing 25% fisheries closure are robust scenarios favored under several combinations of the modeled variables and utility functions. The final chapter explores how the life history parameters of fish species affect the population response to restoration. It is expected that slow growing species would show a greater response to protection than fast growing species. ii Table of Contents Abstract ............................................................................................................................... ii Table of Contents ............................................................................................................... iii List of Tables ..................................................................................................................... ix List of Figures ..................................................................................................................... x Acknowledgements ........................................................................................................... xii Dedication ........................................................................................................................ xiv Co-Authorship Statement.................................................................................................. xv 1 Introduction ................................................................................................................. 1 1.1 Rationale: brief history of fisheries management ................................................ 1 1.2 Context ................................................................................................................. 4 1.2.1 Brief description of study area - Raja Ampat Islands ................................... 5 1.2.2 Historical and political background of marine resource use in Raja Ampat 6 1.2.3 Current management in Raja Ampat ............................................................. 8 1.3 Thesis focus: restoration in fisheries with focus on coral reef ecosystems ........ 10 1.3.1 Restoration within an EBM framework ...................................................... 10 1.3.2 Coral reefs ................................................................................................... 11 1.3.3 Ecopath with Ecosim .................................................................................. 12 1.3.4 Thesis outline .............................................................................................. 13 1.4 References .......................................................................................................... 18 2 Illegal, Unreported and Unregulated Fisheries Catch in Raja Ampat Regency, Eastern Indonesia .............................................................................................................. 29 2.1 Introduction ........................................................................................................ 29 2.1.1 The IUU problem in Indonesia ................................................................... 29 2.1.2 Study area—Raja Ampat Archipelago ........................................................ 30 iii 2.2 Methods .............................................................................................................. 30 2.2.1 Catch reconstruction ................................................................................... 31 2.2.2 Compilation of the influence table .............................................................. 32 2.2.3 Quantifying incentive.................................................................................. 33 2.2.4 Anchor points .............................................................................................. 34 2.2.5 Addressing uncertainty ............................................................................... 36 2.2.6 Quantifying IUU catch revenues in Raja Ampat Regency 2003-2006 ....... 37 2.3 Results ................................................................................................................ 38 2.3.1 Catch reconstruction and IUU catch estimation ......................................... 38 2.3.2 Quantifying the IUU catch revenues in Raja Ampat Regency 2003-2006 . 39 2.4 Discussion .......................................................................................................... 41 2.4.1 Catch reconstruction ................................................................................... 41 2.4.2 Estimation of IUU fishing in Raja Ampat .................................................. 41 2.4.3 Quantifying the economics of IUU catch in Raja Ampat 2003-2006 ......... 48 2.5 Conclusion .......................................................................................................... 49 2.6 References .......................................................................................................... 50 3 Ecological Restoration and Ideal Minimum Size of No-Take Zones in Marine Protected Areas of Raja Ampat, Indonesia ....................................................................... 56 3.1 Introduction ........................................................................................................ 56 3.1.1 MPA for ecosystem based management ..................................................... 56 3.1.2 Raja Ampat ................................................................................................. 57 3.1.3 Birds Head Seascape ecosystem based management project and spatial ecosystem based management research interests ...................................................... 58 3.2 Methods .............................................................................................................. 59 3.2.1 Ecopath with Ecosim and Ecospace ........................................................... 59 3.2.2 Ecospace models used in the analysis ......................................................... 60 iv 3.2.3 Ecosystem effects of restricting fisheries inside the MPAs ........................ 61 3.2.4 Ecological benefits of single large versus several small MPAs ................. 62 3.3 Results ................................................................................................................ 64 3.3.1 Ecosystem effects of restricting fisheries inside the MPAs (Research question-1) ................................................................................................................ 64 3.3.2 Ecological benefits of single large versus several small MPAs ................. 68 3.4 Discussion .......................................................................................................... 70 3.4.1 Ecosystem effects of restricting fisheries inside the MPAs ........................ 70 3.4.2 Ecological benefits of single large versus several small MPAs ................. 72 3.5 Conclusion .......................................................................................................... 74 3.6 References .........................................................................................................