Skip to main content


Log in

Evaluating Tidal Wetland Restoration Performance Using National Estuarine Research Reserve System Reference Sites and the Restoration Performance Index (RPI)

  • Published:
Estuaries and Coasts Aims and scope Submit manuscript


Evaluations of tidal wetland restoration efforts suffer from a lack of appropriate reference sites and standardized methods among projects. To help address these issues, the National Estuarine Research Reserve System (NERRS) and the NOAA Restoration Center engaged in a partnership to monitor ecological responses and evaluate 17 tidal wetland restoration projects associated with five reserves. The goals of this study were to (1) determine the level of restoration achieved at each project using the restoration performance index (RPI), which compares change in parameters over time between reference and restoration sites, (2) compare hydrologic and excavation restoration projects using the RPI, (3) identify key indicator parameters for assessing restoration effectiveness, and (4) evaluate the value of the NERRS as reference sites for local restoration projects. We found that the RPI, modified for this study, was an effective tool for evaluating relative differences in restoration performance; most projects achieved an intermediate level of restoration from 2008 to 2010, and two sites became very similar to their paired reference sites, indicating that the restoration efforts were highly effective. There were no differences in RPI scores between hydrologic and excavation restoration project types. Two abiotic parameters (marsh platform elevation and groundwater level) were significantly correlated with vegetation community structure and thus can potentially influence restoration performance. Our results highlight the value of the NERRS as reference sites for assessing tidal wetland restoration projects and provide improved guidance for scientists and restoration practitioners by highlighting the RPI as a trajectory analysis tool and identifying key monitoring parameters.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others


  • Ball, D.F. 1964. Loss-on-ignition as an estimate of organic matter and organic carbon in non-calcareous soils. Journal of Soil Science 15: 84–92.

    Article  CAS  Google Scholar 

  • Bertness, M.D., P.J. Ewanchuk, and B.R. Silliman. 2002. Anthropogenic modification of New England salt marsh landscapes. Proceedings of the National Academy of Sciences 99: 1395–1398.

    Article  CAS  Google Scholar 

  • Brinson, M.M. 1993. A hydrogeomorphic classification for wetlands. Wetlands Research Program Technical Report WRP-DE-4. U.S. Army Corps of Engineers, Waterways Experimental Station, Vicksburg, Mississippi. 101 pp.

  • Buchsbaum, R.N., J. Catena, E. Hutchins, and M.J. James-Pirri. 2006. Changes in salt marsh vegetation. Phragmites australis, and nekton in response to increased tidal flushing in a New England salt marsh Wetlands 26: 544–557.

    Google Scholar 

  • Burdick, D.M., and R. Konisky. 2003. Determinants of expansion for Phragmites australis, common reed, in natural and impacted coastal marshes. Estuaries 26: 407–416.

    Article  Google Scholar 

  • Burdick, D.M., and C.T. Roman. 2012. Salt marsh responses to tidal restriction and restoration: a summary of experiences. In Tidal marsh restoration: a synthesis of science and practice, ed. C.T. Roman and D.M. Burdick, 373–382. Washington: Island Press.

    Chapter  Google Scholar 

  • Burdick, D.M., M. Dionne, R.M. Boumans, and F.T. Short. 1997. Ecological responses to tidal restorations of two northern New England salt marshes. Wetland Ecology and Management 4: 129–144.

    Article  Google Scholar 

  • Chmura, G.L., D.M. Burdick, and G.E. Moore. 2012. Recovering salt marsh ecosystem services through tidal restoration. In Tidal marsh restoration: a synthesis of science and practice, ed. C.T. Roman and D.M. Burdick, 233–251. Washington: Island Press.

    Chapter  Google Scholar 

  • Clarke, K.R., and M. Ainsworth. 1993. A method of linking multivariate community structure to environmental variables. Marine Ecology Progress Series 92: 205–219.

    Article  Google Scholar 

  • Clarke, K.R., R.N. Gorley, P.J. Somerfield, and R.M. Warwick. 2014. Change in marine communities: an approach to statistical analysis and interpretation, 3rd edition. PRIMER-E: Plymouth.

  • Clewell, A., J. Reiger, and J. Munro. 2005. Guidelines for Developing and Managing Ecological Restoration Projects (2nd edition). Society for Ecological Restoration online publication: Accessed May 23, 2016.

  • Cornu, C.E., and S. Sadro. 2002. Physical and functional responses to experimental marsh surface elevation manipulation in Coos Bay's south slough. Restoration Ecology 10: 474–486.

    Article  Google Scholar 

  • Craft, C.B., S.W. Broome, and C.L. Campbell. 2002. Fifteen years of vegetation and soil development following brackish-water marsh creation. Restoration Ecology 10: 248–258.

    Article  Google Scholar 

  • Craft, C.B., J.M. Reader, J.N. Sacco, and S.W. Broome. 1999. Twenty five years of ecosystem development of constructed Spartina alterniflora (Loisel) marshes. Ecological Applications 9: 1405–1419.

    Article  Google Scholar 

  • Davies, S. 2004. Vegetation dynamics of a tidal freshwater marsh: long-term and inter-annual variability and their relation to salinity. M.S. Thesis. College of William and Mary, Virginia Institute of Marine Science. Gloucester Point, VA. USA. 75. pp.

  • Dean, W. Jr. 1974. Determination of carbonate and organic matter in calcareous sediments and sedimentary rock. Journal of Sedimentary Research 44: 242–248.

    CAS  Google Scholar 

  • Diefenderfer, H.L., R.M. Thom, and J.E. Adkins. 2003. Systematic approach to coastal ecosystem restoration. Prepared for National Oceanic and Atmospheric Administration Coastal Services Center by Battelle Marine Sciences Laboratory, Sequim, WA and NOAA Coastal Services Center, Charleston, SC. 54 pp.

  • Ewanchuk, P.J., and M.D. Bertness. 2003. Recovery of a northern New England salt marsh plant community from winter icing. Oecologia 136: 616–626.

    Article  Google Scholar 

  • Ewanchuk, P.J., and M.D. Bertness. 2004. Structure and organization of a northern New England salt marsh plant community. Journal of Ecology 92: 72–85.

    Article  Google Scholar 

  • Federal Geographic Data Committee (FGDC). 2012. Coastal and marine ecological classification standard. Marine and Coastal Spatial Data Subcommittee. FGDC-STD-018-2012.

  • Godinez-Alvarez, H., J.E. Herrick, M. Mattocks, D. Toledo, and J. Van Zee. 2009. Comparison of three vegetation monitoring methods: their relative utility for ecological assessment and monitoring. Ecological Indicators 9: 1001–1008.

    Article  Google Scholar 

  • Griffin, P.J., T. Theodose, and M. Dionne. 2011. Landscape patterns of forb pannes across a northern New England salt marsh. Wetlands 31: 25–33.

    Article  Google Scholar 

  • Havens, K.J., L.M. Varnell, and J.G. Bradshaw. 1995. An assessment of ecological conditions in a constructed tidal marsh and two natural reference tidal marshes in coastal Virginia. Ecological Engineering 4: 117–141.

    Article  Google Scholar 

  • James-Pirri, M.J., C.T. Roman, and E. L. Nicosia. 2012. Monitoring nekton in salt marshes. A protocol for the National Park Service’s Long-Term Monitoring Program, Northeast Coastal and Barrier Network. Natural Resources Report NPS/NCBN/NRR-2012/579. U.S. Department of the Interior, National Park. Service. Fort Collins, CO. 128 pp.

  • Kentula, M.E. 2000. Perspectives on setting success criteria for wetland restoration. Ecological Engineering 15: 199–209.

    Article  Google Scholar 

  • Kirwan, M.L., G.R. Guntenspergen, and J.T. Morris. 2009. Latitudinal trends in Spartina alterniflora productivity and the response of coastal marshes to global change. Global Change Biology 15: 1982–1989.

    Article  Google Scholar 

  • Konisky, R.A., D.M. Burdick, M. Dionne, and H.A. Neckles. 2006. A regional assessment of salt marsh restoration and monitoring in the Gulf of Maine. Restoration Ecology 14: 516–525.

    Article  Google Scholar 

  • Montgomery, J., C. Zimmermann, and M. Price. 1979. The collection, analysis and variation of nutrients in estuarine pore water. Estuarine and Coastal Marine Science 9: 203–214.

    Article  CAS  Google Scholar 

  • Moore, G.E., D.M. Burdick, C.R. Peter, A. Leonard-Duarte, and M. Dionne. 2009. Regional assessment of tidal marsh restoration in New England using the Restoration Performance Index. Final report submitted to NOAA Restoration Center. 237 pp.

  • Moore, K. 2012. Draft revised NERRS SWMP vegetation monitoring protocol: long-term monitoring of estuarine submersed and emergent vegetation communities. National Estuarine Research Reserve System Technical Report. 25 pp.

  • Moreno-Mateos, D., M.E. Power, F.A. Comín, and R. Yockteng. 2012. Structural and functional loss in restored wetland ecosystems. PLoS Biology 10 (1): e1001247. doi:10.1371/journal.pbio.100124.

    Article  CAS  Google Scholar 

  • Morris, J.T. 2006. Competition among marsh macrophytes by means of geomorphological displacement in the intertidal zone. Estuarine and Coastal Shelf Science 69: 395–402.

    Article  Google Scholar 

  • Morris, J.T. 2007. Ecological engineering intertidal saltmarshes. Hydrobiologia 577: 161–168.

    Article  Google Scholar 

  • Morris, J.T., P.V. Sundareshwar, C.T. Nietch, B. Kjerfve, and D.R. Cahoon. 2002. Responses of coastal wetlands to rising sea level. Ecology 83: 2869–2877.

    Article  Google Scholar 

  • Mossman, H.L., A.J. Davy, and A. Grant. 2012. Does managed coastal realignment create saltmarshes with ‘equivalent biological characteristics’ to natural reference sites? Journal of Applied Ecology 49: 1446–1456.

    Article  Google Scholar 

  • Mudd, S.M. 2011. The life and death of salt marshes in response to anthropogenic disturbance of sediment supply. Geology 39: 511–512.

    Article  Google Scholar 

  • Mudd, S.M., S.M. Howell, and J.T. Morris. 2009. Impact of dynamic feedbacks between sedimentation, sea-level rise, and biomass production on near-surface marsh stratigraphy and carbon accumulation. Estuarine, Coastal and Shelf Science 82: 377–389.

    Article  CAS  Google Scholar 

  • National Estuarine Research Reserve System. 2002. Restoration science strategy: a framework. National Estuarine Research Reserve System Technical Report. National Oceanic and Atmospheric Administration, Silver Spring, Maryland. 33 pp.

  • National Estuarine Research Reserve System. 2012. Sentinel Sites program guidance for climate change impacts. NERRS final program guidance. 24 pp.

  • Neckles, H.A., M. Dionne, D.M. Burdick, C.T. Roman, R. Buchsbaum, and E. Hutchins. 2002. A monitoring protocol to assess tidal restoration of salt marshes on local and regional scales. Restoration Ecology 10: 556–563.

    Article  Google Scholar 

  • Neckles, H.A., G.R. Guntenspergen, W.G. Shriver, N.P. Danz, W.A. Wiest, J.L. Nagel, and J.H. Olker. 2013. Identification of metrics to monitor salt marsh integrity on National Wildlife Refuges in relation to conservation and management objectives. Final report to U.S. Fish and Wildlife Service, Northeast Region. USGS Patuxent Wildlife Research Center, Laurel, MD. 226 pp.

  • Pennings, S.C., and M.D. Bertness. 2001. Salt marsh communities. In Marine community ecology, ed. M.D. Bertness, M.E. Hay, and S.D. Gaines, 289–316. Sunderland, MA: Sinauer.

    Google Scholar 

  • Raposa, K.B., R.L. Weber, M.C. Ekberg, and W. Ferguson. 2015. Vegetation dynamics in Rhode Island salt marshes during a period of accelerating sea level rise and extreme sea level events. Estuaries and Coasts. doi:10.1007/s12237-015-0018-4.

    Google Scholar 

  • Roegner, G.C., H.L. Diefenderfer, A.B. Borde, R.M. Thom, E.M. Dawley, A.H. Whiting, S.A. Zimmerman, and G.E. Johnson. 2008. Protocols for monitoring habitat restoration projects in the Lower Columbia River and Estuary. PNNL-15793. Report by Pacific Northwest National Laboratory, National Marine Fisheries Service, and Columbia River Estuary Study Taskforce submitted to the U.S. Army Corps of Engineers, Portland District, Portland, Oregon.

  • Roman, C.T., M.J. James-Pirri, and J.F. Heltshe. 2001. Monitoring salt marsh vegetation: a protocol for the long-term Coastal Ecosystem Monitoring Program at Cape Cod National Seashore. 47 pp.

  • Roman, C.T., W.A. Niering, and R.S. Warren. 1984. Salt marsh vegetation change in response to tidal restriction. Environmental Management 8: 141–150.

    Article  Google Scholar 

  • Roman, C.T., K.B. Raposa, S.C. Adamowicz, M.J. James-Pirri, and J.G. Catena. 2002. Quantifying vegetation and nekton response to tidal restoration of a New England salt marsh. Restoration Ecology 10: 450–460.

    Article  Google Scholar 

  • Short, F.T., D.M. Burdick, C.A. Short, R.C. Davis, and P.A. Morgan. 2000. Developing success criteria for restored eelgrass, salt marsh and mud flat habitats. Ecological Engineering 15: 239–225.

    Article  Google Scholar 

  • Simenstad, C.A., C.D. Tanner, R.M. Thom, and L. Conquest. 1991. Estuarine habitat assessment protocol. EPA 910/9–91-037, Puget Sound Estuary Program, U.S. Environmental Protection Agency-Region 10, Seattle, WA. 191 pp., plus appendices.

  • Soil Survey Staff. 2014. Soil Survey Field and Laboratory Methods Manual. Soil Survey Investigations Report No. 51, Version 2.0. R. Burt and Soil Survey Staff (ed.). U.S. Department of Agriculture, Natural Resources Conservation Service.

  • Sprecher, S.W. 2000. Installing monitoring wells/piezometers in wetlands. WRAP Technical Notes Collection, ERDC TN-WRAP-00-02, U.S. Army Engineer Research and Development Center, Vicksburg, MS.

  • Staszak, L.A., and A.R. Armitage. 2013. Evaluating salt marsh restoration success with an index of ecosystem integrity. Journal of Coastal Research 29: 410–418.

    Article  Google Scholar 

  • Thayer, G.W., T.A. McTigue, R.J. Salz, D.H. Merkey, F.M. Burrows, and P.F. Gayaldo, (Eds.). 2005. Science-based restoration monitoring of coastal habitats, volume two: tools for monitoring coastal habitats. NOAA Coastal Ocean Program Decision Analysis Series No. 23. NOAA National Centers for Coastal Ocean Science, Silver Spring, MD. 628 pp., plus appendices.

  • Watson, E.B., A.J. Oczkowski, C. Wigand, A.R. Hanson, E.W. Davey, S.C. Crosby, R.L. Johnson, and H.M. Andrews. 2014. Nutrient enrichment and precipitation changes do not enhance resiliency of salt marshes to sea level rise in the northeastern U.S. Climatic Change 125: 501–509.

    Article  CAS  Google Scholar 

  • Wilson, K.R., J.T. Kelley, A. Croitoru, M. Dionne, D. Belknap, and R. Steneck. 2009. Salt pools are secondary and dynamic features of the Webhannet estuary, wells, Maine, USA. Estuaries and Coasts 33: 855–870.

    Article  Google Scholar 

  • Yozzo, D.J., and M.S. Laska. 2006. Restoration program assessment of the National Estuarine Research Reserve System. Ecological Restoration 24: 13–21.

    Article  Google Scholar 

  • Zedler, J.B., and J.C. Callaway. 2000. Evaluating the progress of engineered tidal wetlands. Ecological Engineering 15: 211–225.

    Article  Google Scholar 

Download references


We would like to thank Melanie Gange and the staff at the NOAA Restoration Center, Silver Spring, MD, for providing the funding, staff support, and guidance that made this project possible; everyone who helped with field work across the five reserves; and, specifically, Heidi Harris and Laura Brophy (South Slough, OR), Carolyn Currin and Mike Greene (North Carolina), Willy Reay (Chesapeake Bay, VA), and staff at the NOAA National Geodetic Survey. We especially recognize the contributions of Dr. Michelle Dionne; without her foresight, dedication, and guidance, this project would not have been possible. Finally, we wish to acknowledge the thorough and insightful comments of two anonymous reviewers whose suggestions greatly strengthened the interpretation and applicability of this work.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Kenneth B. Raposa.

Additional information

Commuincated by Edwin DeHaven Grosholz

Electronic Supplementary Material



(PDF 22 kb)



(PDF 19 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Raposa, K.B., Lerberg, S., Cornu, C. et al. Evaluating Tidal Wetland Restoration Performance Using National Estuarine Research Reserve System Reference Sites and the Restoration Performance Index (RPI). Estuaries and Coasts 41, 36–51 (2018).

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: