Description of the program

Bearhead LakePurpose of Sentinel Lakes:

To monitor and model Minnesota lake ecosystems for the detection and better understanding of the effects of environmental stressors in order to guide management that sustains fisheries and water resources for future generations.

Primary goals:

  1. Identify important biological, physical, and chemical trends in Minnesota lakes and monitor these trends over time.
  2. Identify the mechanisms behind the trends that are being observed and monitored.
  3. Identify management solutions to ensure the long-term sustainability of Minnesota's lakes given the presence of large and small-scale ecological disturbances facing these iconic ecosystems.

Additional Goals:

  1. Promote sustainable lake management through timely exchange of information regarding changes to lake conditions, potential causes for those changes, and possible adaptive management approaches.
  2. Identify and monitor methods to improve water quality, fish habitat, and fishing.
  3. Improve public understanding of lake habitats, environmental stressors, and ecological responses to stressors.
  4. Regularly report on the physical, chemical, and biological condition of sentinel lakes based on monitoring of key status indicators.
  5. Integrate research efforts into the monitoring program so mechanisms behind changes are well understood.
  6. Assemble relevant biological, physical, and chemical data sets in such a manner that they attract interdisciplinary partnerships and leverage in-kind resources.
  7. Integrate lake monitoring efforts being conducted by other programs/agencies and continually improve data and information exchange.
  8. Regularly review the Sentinel Lakes Program to ensure ongoing relevancy while maintaining the integrity and continuity of important historical datasets.


  • 25 sentinel lakes
  • Measurement of a host of watershed, water quality, zooplankton, aquatic plant, and fish indicators
  • Evaluation of metrics that are the most relevant and sensitive indicators of the status of lake habitats and fish communities
  • Propose indicators and monitoring schedules in sentinel lakes and additional random lakes that cover larger numbers of lakes across broader geographic areas.
    • The focus of sentinel lake monitoring will be intensive and focused on better understanding cause effect relationships between stressors and lake status indicators, predictive modeling, and early detection of problems.
    • The focus of random lake monitoring will be extensive; monitoring fewer indicators less often, and designed to cover a wider range of lake systems. This component assesses the geographic scale of trends and provides an important "cross-check" of patterns observed in the sentinel lakes.
    • Combining both intensive and extensive approaches is a powerful and novel approach towards assessing status and trends in lake habitats and communities.



  • 25 Lake Assessment Reports
  • Monitoring schedules and models that will facilitate early detection of potential impairments to lake habitats and fish communities.
  • Identifying and focusing future monitoring activities on a set of habitat and fish indicators that change predictably as lakes become more nutrient-rich and warmer, yet are relatively stable under normal conditions.
  • Many contributing research explorations