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Attachment C3-20: Ecopath with Ecosim (Ewe)

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Attachment C3-20: Ecopath with Ecosim (Ewe) Coastal Protection and Restoration Authority 150 Terrace Avenue, Baton Rouge, LA 70802 | [email protected] | www.coastal.la.gov 2017 Coastal Master Plan Attachment C3-20: Ecopath with Ecosim (EwE) Report: Version I Date: December 2015 Prepared by: Kim de Mutsert (George Mason University), Kristy Lewis (George Mason Universeity), Joe Buszowski (Ecopath Research and Development Consortium), Jeroen Steenbeek (Ecopath Research and Development Consortium), Scott Milroy (University of Southern Mississippi) 2017 Coastal Master Plan: Ecopath with Ecoism (EwE) Coastal Protection Restoration Authority This document was prepared in support of the 2017 Coastal Master Plan being prepared by the Coastal Protection and Restoration Authority (CPRA). CPRA was established by the Louisiana Legislature in response to Hurricanes Katrina and Rita through Act 8 of the First Extraordinary Session of 2005. Act 8 of the First Extraordinary Session of 2005 expanded the membership, duties and responsibilities of CPRA and charged the new authority to develop and implement a comprehensive coastal protection plan, consisting of a master plan (revised every five years) and annual plans. CPRA’s mandate is to develop, implement and enforce a comprehensive coastal protection and restoration master plan. Suggested Citation: De Mutsert, K., Lewis, K.A., Buszowski, J., Steenbeek, J. and Milroy, S. (2015). 2017 Coastal Master Plan Modeling: C3-20 – Ecopath with Ecosim. Version I. (pp. 1-97). Baton Rouge, Louisiana: Coastal Protection and Restoration Authority. Page | ii 2017 Coastal Master Plan: Ecopath with Ecoism (EwE) Acknowledgements This document was developed as part of a broader Model Improvement Plan in support of the 2017 Coastal Master Plan under the guidance of the Modeling Decision Team (MDT): The Water Institute of the Gulf - Ehab Meselhe, Alaina Grace, and Denise Reed Coastal Protection and Restoration Authority (CPRA) of Louisiana – Mandy Green, Angelina Freeman, and David Lindquist We would like to acknowledge the following Institutions who provided data, input parameters, or comments on earlier drafts of this manuscript: CPRA The Water Institute of the Gulf Louisiana Department of Wildlife and Fisheries U.S. Geological Survey, National Wetlands Research Center Moffatt and Nichol This effort was funded by the CPRA of Louisiana under Cooperative Endeavor Agreement Number 2503-12-58, Task Order No. 03. Page | iii 2017 Coastal Master Plan: Ecopath with Ecoism (EwE) Executive Summary Unlike the 2012 Coastal Master Plan, the 2017 Coastal Master Plan modeling effort includes a fish and shellfish community modeling approach. A spatially explicit ecosystem model was developed in the Ecopath with Ecosim (EwE) software suite to simulate fish biomass distribution through time and space. EwE is an open source ecosystem modeling software consisting of three modules: Ecopath, Ecosim, and Ecospace. Ecopath is a virtual representation of the food web of an ecosystem, including flows and pools of biomass within this food web. Ecosim then allows for temporal simulations of changes in biomass of groups in the model (which could be species or functional groups) in response to changes in water quality variables (such as nutrient loads and salinity) over time. Lastly, Ecospace allows for spatial and temporal simulations of biomass change of each of the groups in response to spatially and temporally explicit drivers, forcing functions, and habitat characteristics. This feature not only provides information on the spatial distribution of each group in the model, it also improves estimates of total biomass changes of each group over the course of the model run because movement of consumers and spatially explicit habitat characteristics of the system are taken into consideration. Page | iv 2017 Coastal Master Plan: Ecopath with Ecoism (EwE) Table of Contents Coastal Protection Restoration Authority ...................................................................................................... ii Acknowledgements ......................................................................................................................................... iii Executive Summary ......................................................................................................................................... iv List of Tables ...................................................................................................................................................... vii List of Figures ..................................................................................................................................................... vii List of Abbreviations .......................................................................................................................................... x 1.0 Introduction .................................................................................................................................................. 1 2.0 General Description of Ecopath with Ecosim........................................................................................ 1 2.1 Ecopath: Structure and Assumptions ...................................................................................................... 2 2.2 Ecosim: Structure and Assumptions ........................................................................................................ 3 2.2.1 Foraging Arena Theory ........................................................................................................................... 4 2.2.2 Calibration and Validation .................................................................................................................... 4 2.3 Ecospace: Structure and Assumptions ................................................................................................... 5 2.3.1 The Habitat Capacity Model ................................................................................................................ 5 2.3.2 Use of GIS in Ecospace ........................................................................................................................... 6 3.0 Development of Master Plan EwE Model .............................................................................................. 8 3.1 Model Domain ............................................................................................................................................. 8 3.2 Biological Data Collection and Preparation ......................................................................................... 9 3.3 Environmental Parameters ...................................................................................................................... 14 3.4 Fishery Data ................................................................................................................................................ 14 3.5 Ecopath with Ecosim ................................................................................................................................ 14 3.5.1 Ecopath Model Development ............................................................................................................ 14 3.5.2 Calibration and Sensitivity Analysis in Ecosim ................................................................................... 16 3.5.3 Preparing the Ecospace Module ....................................................................................................... 19 3.5.4 Oyster Environmental Capacity Layers ............................................................................................. 23 3.5.5 Validation ................................................................................................................................................ 25 3.6 Linking the ICM to EWE ............................................................................................................................ 26 3.7 50-Year Test Simulation Set-Up ............................................................................................................... 26 3.8 Key Model Assumptions and Limitations .............................................................................................. 27 4.0 Results .......................................................................................................................................................... 27 4.1 Ecopath ...................................................................................................................................................... 27 4.2 Model Tuning and Testing ....................................................................................................................... 32 4.2.1 Sensitivity Analysis .................................................................................................................................. 32 4.2.2 Calibration Results ................................................................................................................................. 32 4.2.3 Validation Results ................................................................................................................................... 36 4.2.4 50-Year Simulation ................................................................................................................................. 38 4.3 Example Output ........................................................................................................................................ 38 5.0 Summary ....................................................................................................................................................
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