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Characterizing the Effectiveness of No Net Loss : A Case Study in Northern Michigan. Andrew T. Kozich Kathleen E. Halvorsen. Michigan Technological University. Introduction. Wetland mitigation Michigan: Oversight by MDNRE CWA Section 404 permits Restoration Creation No Net Loss.
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Characterizing the Effectiveness of No Net Loss: A Case Study in Northern Michigan Andrew T. Kozich Kathleen E. Halvorsen Michigan Technological University
Introduction Wetland mitigation Michigan: Oversight by MDNRE CWA Section 404 permits Restoration Creation No Net Loss
Introduction (cont.) • Mitigation wetlands: Intended to provide functions and values of the original wetlands • Permittees: Expected to meet all requirements described on permit • Design, construction, monitoring, document submission, any necessary follow-up or “repairs”
Literature Review • Mitigation sites often do not meet design criteria or permit requirements • (Brody & Highfield 2005; Brown & Veneman 2001; Burgin 2010; Campbell et.al. 2002; Dale & Gerlak 2007; Euliss et.al. 2008; Malakoff 1998; Morgan & Roberts 2003; Reiss et.al. 2009) • Invasive plant species often problematic at mitigation sites • (Balcombe et al 2005; Cole & Shafer 2002; Hoeltje & Cole 2008; Moore et.al. 1999; Spieles 2005; Spieles et.al. 2006; Zedler & Kercher 2004)
Literature Review (cont.) • Michigan’s western Upper Peninsula: 48% of mitigation permit files missing monitoring reports, conservation easement documents, or both • (Hornyak & Halvorsen 2003) • Permit inspections only • No site examinations
Three key MDNRE mitigation policies • Site monitoring reports must be submitted annually for 5 years • Wetland acreage must be placed into conservation easement • Invasive species must be limited to 10% of total cover
Research Design & Questions • Update file inspections: Has compliance with monitoring & conservation easements changed since 2003? • Include site examinations: Is there a relationship between site monitoring and invasive species? • Examine landscape placement: Do other factors appear to be influencing levels of invasive species? • Compare restored and created wetlands: Are differences apparent?
Research Design (cont.) • Permit files: All Upper Peninsula mitigation permits issued between 2003 and 2006 • 69 files; 37 mitigation sites • Site examinations: All mitigation sites constructed by road agencies between 2003 and 2006 • 11 sites in western Upper Peninsula • Releve sampling • Compliance with 10% invasive species limit
Results • Mitigation permit compliance: • Site monitoring documents: 20/37 54% • Conservation easement documents: 35/69 51% • Invasive species limit: 5/11 45%
Results (cont.) • Sites compliant for invasive species: 60% had been monitored • Sites non-compliant for invasive species: 60% had been monitored Monitoring likely not related to levels of invasive species at mitigation sites... ...Other factors involved?
Results (cont.) Distance to nearest road Age of mitigation sites No statistical significance
Results (cont.) • Restored wetlands: 100% compliant • Created wetlands: 0% compliant Landscape location related to levels of invasive species at mitigation sites... ...Hydrology appears to be key! (Bedford 1996; Zedler 1996)
Red = wetland creation Green = wetland restoration Site size (acres)
Discussion • Mitigation practices are resulting in increased acreage but decreased overall quality of wetlands • (Bies 2006; Burgin 2010; Dale & Gerlak 2007; Turner et.al. 2001; Zedler 1996) • No Net Loss: 74 acres lost; 185 acres gained • 30% of wetland acreage gained meeting performance standards for invasive species • Primary limitation: sample size
Discussion (cont.) • Policy efforts should emphasize the importance of mitigation site selection • (Hoeltje & Cole 2008; Smith et.al. 2008) • Restoration is typically a better option than creation • (Euliss et.al. 2008; Mitsch & Gosselink 2000) • Importance of project planning and follow-up • (Brody & Highfield 2005; Ehrenfeld 2000)
Conclusions • Permit file compliance: Little change since 2003 • Site monitoring not related to invasive species, but landscape location is • Smaller restoration projects more successful than larger creation projects • Future research: Compare to older mitigation sites, expand study area, examine hydrology