015 National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Natural Resource Condition Assessment Voyageurs National Park Natural Resource Report NPS/VOYA/NRR—2015/1007 ON THE COVER Beaver Point overlook, Voyageurs National Park Photograph by: Dave Mechenich Natural Resource Condition Assessment Voyageurs National Park Natural Resource Report NPS/VOYA/NRR—2015/1007 Christine Mechenich1, Justin A. VanDeHey2, James E. Cook2, David J. Mechenich1, Jennifer L. McNelly1, and George J. Kraft1 1Center for Watershed Science and Education College of Natural Resources University of Wisconsin – Stevens Point Stevens Point, Wisconsin 54481 2College of Natural Resources University of Wisconsin – Stevens Point Stevens Point, Wisconsin 54481 August 2015 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate comprehensive information and analysis about natural resources and related topics concerning lands managed by the National Park Service. The series supports the advancement of science, informed decision-making, and the achievement of the National Park Service mission. The series also provides a forum for presenting more lengthy results that may not be accepted by publications with page limitations. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. This report received informal peer review by subject-matter experts who were not directly involved in the collection, analysis, or reporting of the data. Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Government. This report is available in digital format from the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/nrpm/). To receive this report in a format optimized for screen readers, please email [email protected]. Please cite this publication as: Mechenich, C., J. A. VanDeHey, J. E. Cook, D. J. Mechenich, J. L. McNelly, and G. J. Kraft. 2015. Natural resource condition assessment: Voyageurs National Park. Natural Resource Report NPS/VOYA/NRR—2015/1007. National Park Service, Fort Collins, Colorado. NPS 172/129525, August 2015 ii Contents Page Figures.................................................................................................................................................. vii Tables .................................................................................................................................................... xi Executive Summary ............................................................................................................................xiii Acknowledgments .............................................................................................................................. xvii List of Terms ....................................................................................................................................... xix 1. NRCA Background Information ........................................................................................................ 1 2. Introduction and Resource Setting ..................................................................................................... 5 2.1. Introduction ............................................................................................................................. 5 2.1.1. Enabling Legislation ........................................................................................................ 5 2.1.2. Geographic Setting .......................................................................................................... 5 2.1.3. Demographics and Visitation .......................................................................................... 5 2.2. Natural Resources .................................................................................................................. 11 2.2.1. Climate .......................................................................................................................... 11 2.2.2. Geology ......................................................................................................................... 11 2.2.3. Ecological Units and Watersheds .................................................................................. 11 2.2.4. Resource Descriptions ................................................................................................... 12 2.2.5. Resource Issues Overview ............................................................................................. 12 2.3. Resource Stewardship ........................................................................................................... 17 2.3.1. Management Directives and Planning Guidance........................................................... 17 2.3.2. Status of Supporting Science ......................................................................................... 17 3. Study Scoping and Design ............................................................................................................... 23 3.1. Preliminary Scoping .............................................................................................................. 23 3.2. Study Design ......................................................................................................................... 23 3.2.1. Indicator Framework, Focal Study Resources and Indicators ....................................... 23 3.2.2. Reference Conditions and Trends ................................................................................. 23 3.2.3. Reporting Areas ............................................................................................................. 24 3.2.4. General Approach and Methods .................................................................................... 24 4. Natural Resource Conditions ........................................................................................................... 27 iii Contents (continued) Page 4.1. Disturbance Regimes ............................................................................................................. 27 4.1.1. Fire ................................................................................................................................. 28 4.1.2. Wind .............................................................................................................................. 30 4.1.3. Herbivory ....................................................................................................................... 31 4.1.4. Logging (1800s–1971) .................................................................................................. 36 4.2. Landscape Condition ............................................................................................................. 45 4.2.1. Land Cover .................................................................................................................... 45 4.2.2. Impervious Surfaces ...................................................................................................... 51 4.2.3. Landscape Pattern and Structure ................................................................................... 52 4.2.4. Road Density ................................................................................................................. 61 4.2.5. Lightscapes .................................................................................................................... 67 4.2.6. Soundscapes .................................................................................................................. 69 4.3. Biotic Condition .................................................................................................................... 72 4.3.1. Vegetation...................................................................................................................... 72 4.3.2. Wetlands – Wild Rice Marshes ..................................................................................... 83 4.3.3. Terrestrial Exotic Plants ................................................................................................ 87 4.3.4. Exotic Organisms––Earthworms ................................................................................... 91 4.3.5. Moose ............................................................................................................................ 95 4.3.6. Beaver Population Dynamics and Landscape Influence ............................................. 102 4.3.7. Climate Change and Terrestrial Systems ...................................................................