MAISRC researchers are updating Minnesota’s boater movement network using 2018-2022 watercraft inspection data to analyze trends, model how state and county agencies can better collaborate through game theory, and enhance the AIS Explorer tool to help managers more effectively plan inspections and prevent the spread of aquatic invasive species.
Background:
This project is in phase III: working to prevent the spread of aquatic invasive species (AIS) in Minnesota by improving how watercraft inspection resources are allocated and coordinated across state and county levels. Building on previous work that quantified the benefits of collaboration among agencies, this project is using updated watercraft inspection data (2018–2022) to better understand boater movement patterns, optimize inspection planning through game-theoretic modeling, and integrate findings into the AIS Explorer decision-support tool. These efforts aim to improve inspection efficiency, enhance county collaboration, and strengthen Minnesota’s AIS prevention programs.
Project goals:
Analyze updated boater movement networks (2018–2022) to identify trends, assess changes over time, and compare results to earlier networks (2014–2017).
Develop a bi-level game-theoretic model to evaluate and improve collaboration between counties and the Minnesota DNR in inspection planning.
Integrate new data and modeling outputs into the AIS Explorer dashboard to help county managers jointly plan inspections and explore the benefits of sharing inspection budgets.
Phase II progress
MAISRC researchers have been working with data from the Minnesota Department of Natural Resources' (MN DNR) watercraft inspection program, covering the years 2017 to 2023. This data includes approximately 3.6 million connections across 913 inspection locations, and it has been used to create updated models of boater movement networks. In parallel, the team has advanced their game theory models to study decision-making at the county level.
They developed a non-cooperative game model using integer programming, where each of Minnesota's 81 counties makes decisions based on its own goals. This research revealed at least one pure Nash Equilibrium (PNE), a scenario where no county has the incentive to change its strategy as long as the others maintain theirs. This finding is particularly important because previous studies have only considered games with 2-3 players.
The research team created a cooperative model that allows counties to pool their budgets while still maintaining the benefits identified in the non-cooperative approach. This new framework connects non-cooperative game theory with more centralized decision-making strategies, offering a novel approach to fostering collaboration between counties.
Phase I
MAISRC researchers evaluated how different levels of coordination among state and county agencies affect the efficiency of Minnesota’s watercraft inspection programs, which are a key tool for preventing the spread of aquatic invasive species (AIS).
Using computer models, they compared several approaches, from a fully state-coordinated plan to strategies involving independent or cooperative county management. The models showed that statewide coordination could inspect over 95% of high-risk boats with about 400 inspectors, while decentralized, county-led plans were 10–20% less effective. Collaborative approaches between counties improved efficiency compared to working independently, especially when sharing information or budgets, though they still fell short of the optimal statewide plan. These findings offer insights to help improve AIS prevention and management efforts across Minnesota.