Optimization of Salt Marsh Management at the Moosehorn National Wildlife Refuge, Maine, Through Use of Structured Decision Making

Open-File Report 2021-1115
Prepared in cooperation with the U.S. Fish and Wildlife Service
By: , and 



Structured decision making is a systematic, transparent process for improving the quality of complex decisions by identifying measurable management objectives and feasible management actions; predicting the potential consequences of management actions relative to the stated objectives; and selecting a course of action that maximizes the total benefit achieved and balances tradeoffs among objectives. The U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, applied an existing, regional framework for structured decision making to develop a prototype tool for optimizing tidal marsh management decisions at the Moosehorn National Wildlife Refuge in Maine. Refuge biologists, refuge managers, and research scientists identified multiple potential management actions to improve the ecological integrity of four marsh management units within the refuge, totaling about 13 hectares, and estimated the outcomes of each action in terms of performance metrics associated with each management objective. Value functions previously developed at the regional level were used to transform metric scores to a common utility scale, and utilities were summed to produce a single score representing the total management benefit that could be accrued from each potential management action. Constrained optimization was used to identify the set of management actions, one per marsh management unit, that could maximize total management benefits at different cost constraints at the refuge scale. Results indicated that, for the objectives and actions considered here, total management benefits may increase consistently up to $1,000, and may continue to increase at a lower rate with further expenditures. Potential management actions in optimal portfolios at total costs less than or equal to $1,000 included improving nesting habitat for Ammodramus nelsoni (Nelson’s sparrow) or restoring hydrologic connections to the upper marsh in one marsh management unit (Hobart Stream West). The potential management benefits were derived from expected increases in the density of nekton and of spiders (as an indicator of trophic health). The prototype presented here does not resolve management decisions; rather, it provides a framework for decision making at the Moosehorn National Wildlife Refuge that can be updated for implementation as new data and information become available. Insights from this process may also be useful to inform future habitat management planning at the refuge.

Suggested Citation

Neckles, H.A., Lyons, J.E., Nagel, J.L., Adamowicz, S.C., Mikula, T., Mills, M., Brown, R.E., and Ramos, K., 2021, Optimization of salt marsh management at the Moosehorn National Wildlife Refuge, Maine, through use of structured decision making: U.S. Geological Survey Open-File Report 2021–1115, 28 p., https://doi.org/10.3133/ofr20211115.

ISSN: 2331-1258 (online)

Study Area

Table of Contents

  • Acknowledgments 
  • Abstract 
  • Introduction 
  • Regional Structured Decision-Making Framework 
  • Application to the Moosehorn National Wildlife Refuge 
  • Results of Constrained Optimization 
  • Considerations for Optimizing Salt Marsh Management 
  • References Cited 
  • Appendix 1. Regional Influence Diagrams 
  • Appendix 2. Utility Functions for the Moosehorn National Wildlife Refuge
Publication type Report
Publication Subtype USGS Numbered Series
Title Optimization of salt marsh management at the Moosehorn National Wildlife Refuge, Maine, through use of structured decision making
Series title Open-File Report
Series number 2021-1115
DOI 10.3133/ofr20211115
Year Published 2021
Language English
Publisher U.S. Geological Survey
Publisher location Reston, VA
Contributing office(s) Patuxent Wildlife Research Center, Eastern Ecological Science Center
Description Report: vi, 28 p.; Database
Country United States
State Maine
Other Geospatial Moosehorn National Wildlife Refuge
Online Only (Y/N) Y
Additional Online Files (Y/N) N
Google Analytic Metrics Metrics page
Additional publication details