Prepared in cooperation with the Louisiana Coastal Protection and Restoration Authority Louisiana Barrier Island Comprehensive Monitoring Program: Mapping Habitats in Beach, Dune, and Intertidal Environments Along the Louisiana Gulf of Mexico Shoreline, 2008 and 2015–16 Open-File Report 2020–1030 U.S. Department of the Interior U.S. Geological Survey Cover: Examples of various habitats found on Louisiana’s barrier islands, headlands, and along coastal shorelines. Top row from left to right: estuarine emergent marsh and water; estuarine emergent marsh, intertidal, and water habitats being utilized by shorebirds; beach transitioning into unvegetated flat and meadow. Middle row from left to right: estuarine emergent marsh, meadow, and water; beach, unvegetated dune with sand fencing, unvegetated flat, and vegetated dune; meadow and scrub/shrub. Bottom row from left to right: unvegetated flat and meadow habitats; mangrove colonization on a recently restored back- barrier intertidal platform; meadow, scrub/shrub, estuarine emergent marsh, and mangrove habitats (listed in order from foreground to background). Photographs by the Louisiana Coastal Protection and Restoration Authority (2007, 2008, and 2019), used with permission. Louisiana Barrier Island Comprehensive Monitoring Program: Mapping Habitats in Beach, Dune, and Intertidal Environments Along the Louisiana Gulf of Mexico Shoreline, 2008 and 2015–16 By Nicholas M. Enwright, William M. SooHoo, Jason L. Dugas, Craig P. Conzelmann, Claudia Laurenzano, Darin M. Lee, Kelly Mouton, and Spencer J. Stelly Prepared in cooperation with the Louisiana Coastal Protection and Restoration Authority Open-File Report 2020–1030 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior DAVID BERNHARDT, Secretary U.S. Geological Survey James F. Reilly II, Director U.S. Geological Survey, Reston, Virginia: 2020 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit https://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit https://store.usgs.gov/. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: Enwright, N.M., SooHoo, W.M., Dugas, J.L., Conzelmann, C.P., Laurenzano, C., Lee, D.M., Mouton, K., and Stelly, S.J., 2020, Louisiana Barrier Island Comprehensive Monitoring Program—Mapping habitats in beach, dune, and intertidal environments along the Louisiana Gulf of Mexico shoreline, 2008 and 2015–16: U.S. Geological Survey Open-File Report 2020–1030, 57 p., https://doi.org/ 10.3133/ ofr20201030. Associated data for this publication: Enwright, N.M., SooHoo, W.M., Dugas, J.L., Lee, D.M., and Borrok, P.S., 2018, Louisiana Barrier Island Comprehensive Monitoring Program—Habitat mapping: U.S. Geological Survey data release, https://doi.org/10.5066/F7XP7440. ISSN 2331-1258 (online) iii Acknowledgments This effort was funded by the Louisiana Coastal Protection and Restoration Authority’s (CPRA) Barrier Island Comprehensive Monitoring program. We would like to thank Syed Khalil (CPRA) for numerous helpful discussions about the habitat mapping methods and analysis for this proj- ect. We thank John Barras for his assistance with the development of coastal reach boundaries for this effort. We are grateful to Hana Thurman (Cherokee Nation Technologies) for her assis- tance with designing the cover graphic. Finally, we thank Syed Khalil, Glen Curole (CPRA), Brady Couvillion (U.S. Geological Survey; USGS), and Richard Day (USGS) for reviewing this report. v Contents Acknowledgments ........................................................................................................................................iii Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................2 Methods...........................................................................................................................................................3 Delineation and Description of Study Area ......................................................................................3 Hurricanes, Extreme Storms, and Restoration Efforts ....................................................................5 Habitat Mapping....................................................................................................................................5 Habitat Classification Schemes ................................................................................................5 Source Data and Preprocessing ...............................................................................................6 Elevation Uncertainty and Monte Carlo Simulations .............................................................9 Dune Extraction Approach .......................................................................................................10 Object-Based Image Analysis .................................................................................................10 Data Post-Processing ...............................................................................................................11 Habitat Classification Accuracy Assessment .......................................................................11 Habitat Change and Accuracy Assessment ..................................................................................12 Habitat Reporting Tool ........................................................................................................................14 Data Analyses......................................................................................................................................14 Results and Discussion �������������������������������������������������������������������������������������������������������������������������������14 Habitat and Habitat Change Data ....................................................................................................14 Habitat and Habitat Change Accuracy ...........................................................................................14 BICM Region-Wide Habitat and Habitat Change ..........................................................................19 West Chenier Plain Region Habitat and Habitat Change .............................................................23 East Chenier Plain Region Habitat and Habitat Change ...............................................................26 Acadiana Bays Region Habitat and Habitat Change ....................................................................30 Early Lafourche Delta Region Habitat and Habitat Change .........................................................32 Late Lafourche Delta Region Habitat and Habitat Change ����������������������������������������������������������34 Modern Delta Region Habitat and Habitat Change .......................................................................36 Chandeleur Islands Region Habitat and Habitat Change .............................................................39 Future Efforts ................................................................................................................................................41 Summary........................................................................................................................................................42 References Cited..........................................................................................................................................42 Appendix 1.....................................................................................................................................................47 Figures 1. Map showing regions and reaches along the Louisiana Gulf of Mexico shoreline mapped during the 2008 and 2015–16 habitat mapping efforts for the Louisiana Barrier Island Comprehensive Monitoring Program ............................................4 2. Chart showing an overview of the Monte Carlo error propagation process for estimating the probability of a pixel being above or below a specific elevation threshold for digital elevation models for the Louisiana Barrier Island Comprehensive Monitoring Program habitat mapping effort along the Louisiana Gulf of Mexico shoreline ...........................................................................................................10 vi 3. Example of workflow for using geographic object-based image analyses for habitat mapping for the Louisiana Barrier Island Comprehensive Monitoring Program ...................................................................................................................11 4. Chart showing an overview of the mapping process used for the barrier island habitat maps for the Louisiana Barrier Island Comprehensive Monitoring Program for the detailed scheme ............................................................................................12 5. Maps