Overview of Methods. Terrestrial areas that are most important for conservation Conservation

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1 Overview of Methods The goal of the Western Lake Erie Coastal Conservation Vision project (WLECCV) is to define where we should be working locally to optimally achieve regional conservation impact. The regional context for the WLECCV is established by the Lake Erie Biodiversity Conservation Strategy (LEBCS), which identifies biodiversity conservation targets (ecological systems and groups of species of lakewide importance) and sets goals for those targets. The WLECCV incorporates those targets and goals into a spatial optimization process employing the widely used conservation planning software Marxan that is described in this fact sheet. What is Marxan, and why use Marxan with Zones? Marxan 1 software is used throughout the world to provide decision support to a range of conservation planning problems, including reserve design, reporting on the performance of existing reserve systems, and developing multiple-use zoning plans for natural resource management. Marxan is flexible in allowing users to define conservation interests and other values and then explore options for meeting goals for those values and interests in the most cost effective, spatially explicit manner. Effective use of Marxan requires spatial data on the values as well as factors that might constrain conservation action, such as land values or competing uses. In many reserve design processes, the objective is to develop a set of areas that, if conserved, would meet goals for the conservation targets. Conservation planners are increasingly incorporating objectives beyond traditional conservation that demand identification of areas within which multiple actions would be permitted. Analogous to municipal zoning, this kind of conservation planning seeks to accommodate multiple values in a shared geographic region. A variation of Marxan software known as Marxan with Zones or MarxanZ allows mapping of zones for different kinds of activities, some restricted and others multiple-use. The WLECCV analysis area incorporates coastal and inland areas as well as large areas of water especially the Detroit River and the western basin of Lake Erie. Conservation and restoration activities are well understood for land areas, but aren t well established for the Great Lakes (the Thunder Bay National Marine Sanctuary in Lake Huron is one exception). Since the WLECCV is addressing both land and water areas, we used Marxan with Zones to enable us to distinguish two kinds of zones including areas for traditional conservation and restoration from areas of aquatic importance (Table 1). Table 1. Zones used in the WLECCV project. Zone Name Description Terrestrial areas that are most important for conservation Conservation and restoration Areas in the lake important for biodiversity and cultural Important Aquatic Area resources. 1 Marxan software and supporting information is available at

2 Critical Components of Marxan Analysis In addition to the zones described above, there are three key components that must be developed prior to running Marxan: Features, Costs, and Planning Units. Each is defined and briefly described below; more information about individual features or costs is available in additional, specific fact sheets. Features Features are the objects of conservation interest in a Marxan analysis; i.e., the things that should be conserved. They are analogous to conservation targets, and traditionally are species, natural communities, or ecological systems. The WLECCV analysis addresses not only ecological features as defined by the LEBCS but also socioeconomic values, or the things that people value in the coastal area of western Lake Erie. Therefore, we identified two sets of features: Ecological and Socioeconomic. Ecological Features The LEBCS defines a set of conservation targets that were adopted for the WLECCV, along with the goals for these targets; some goals were revised based on new information. These ecological conservation targets and goals are listed Table 2. To spatially represent these ecological targets, the WLECCV team sought data sets from partners and, in a few cases, developed new data sets Each of these data sets corresponds to an attribute of one or more ecological target, such as habitat availability or biodiversity significance, and these spatial data sets are used as the ecological features in the Marxan analysis (Table 3). Socioeconomic Features The western Lake Erie coastal area holds enormous cultural and economic importance, both to local communities and at a regional and global scale. The WLECCV seeks is developing a vision for conservation that incorporates important socioeconomic values such that conservation and restoration actions would benefit people. To focus on socioeconomic values that are both important in the coastal area and that are likely to benefit from conservation and restoration actions, we drew upon an ecosystem services assessment completed as part of the LEBCS. The WLECCV project team sought data sets to spatially represent the ten most important ecosystem services identified in the LEBCS. Of these, we identified spatial data layers to represent five (Table 4). Costs To represent the costs of implementing conservation and restoration actions, we identified seven cost layers, four of which are characterized in monetary values derived from conservation and restoration projects, and three of which are cost indices reflecting landscape attributes that affect the feasibility of effective conservation (Table 5).

3 Table 2. Ecological conservation targets and goals for the WLECCV ECOLOGICAL TARGETS GOALS/ULTIMATE OUTCOMES Nearshore Zone At least 25% of the coastal wetland area will be hydrologically connected to L. Erie s nearshore system. Native Migratory Fish Shoreline hardening is < 20% along the WLE coast. At least 50% of the total length of each type of stream is connected to Lake Erie (accessible by fish). Coastal Wetlands Coastal wetland area around Lake Erie will have increased by 10% by 2030 compared to 2011 Coastal Terrestrial Systems Percent cover of Phragmites will be < 20%. At least 40% of the coastal terrestrial system will be in natural land cover. All significant biodiversity areas in the coastal terrestrial system are unaffected by shoreline alterations. Aerial Migrants At least 40% of area within 1km of the shoreline is suitable for migrating landbirds. At least 40% of area between 1-25km from the shoreline is suitable for landbirds. At least 80% of the 2km coastal area that is high quality stopover habitat for all bird groups is in conservation ownership or management. At least 30% of the area within 3.2 km of the shoreline is suitable for migrating shorebirds. At least 50% of the 2km coastal area, including coastal wetlands, comprises high quality stopover habitat for migrating waterfowl. Detroit River Shoreline hardening is below 50% along both shores. Coastal wetlands in the Detroit River comprise at least 25% of historic area. Islands A minimum of 30% of Lake Erie islands are owned and managed for conservation. A minimum of 40% of Lake Erie islands are in natural land cover. Maintain island habitat in an undeveloped condition to support colonial nesting waterbirds, including cormorants, on the islands that have been historically used by nesting colonial waterbirds.

4 Table 3. Ecological targets and corresponding Marxan features for the WLECCV. Ecological Conservation Targets Data Layers used as Marxan Features Nearshore Zone Native Migratory Fish Coastal Wetlands Coastal Terrestrial Systems Aerial Migrants Connecting Channels (Detroit River) Islands Walleye Spawning Sites Walleye Lake Habitat Walleye Stream Habitat Potential Coastal Wetlands Coastal Terrestrial Biodiversity Significance Coastal Landbird Habitat Inland Landbird Habitat Shorebird Habitat Nearshore Waterfowl Habitat Inland Waterfowl Habitat Potential Coastal Wetlands Detroit River Spawning Sites (sturgeon, whitefish, walleye) Detroit River Walleye Habitat Coastal Terrestrial Biodiversity Significance Table 4. Socioeconomic values and features used in the WLECCV Marxan analysis. Human Well-being Targets Data Layers used as Marxan Features Health Spiritual & Cultural Fulfillment Living Standards Connection to Nature Drinking water protection areas Beaches Parks Trails Hunting areas Recreational boating Recreational fishing Shipwrecks (dive sites) Commercial Fishing Hunting areas Nature based education sites Water access sites

5 Table 5. Costs of implementing conservation and restoration actions in the coastal areas of western Lake Erie. Cost Units Land value $ Wetland restoration $ Phragmites treatment $ Marinas cost to wetlands GLEAM Multi-stressor index Landbird habitat restoration $ Walleye stream habitat improvement cost Planning Units To enable Marxan to map an optimal set of areas for achieving goals and minimizing costs, users must provide a set of pre-defined spatial units planning units and attribute each of the planning units with values for features, costs, and boundary length. Planning units can comprise a regular, continuous grid or be discreet units of varying size and shape, depending on the objectives of the reserve design. For the WLECCV, we chose to use a regular grid of 10-ha (roughly 25 acres) hexagons covering the entire analysis area defined as the watershed of the Detroit River and western basin of Lake Erie, extending a maximum of 25 km from the coast. This framework includes over 120,000 hexagons, which represents a reasonable tradeoff in computing time while still providing results at a scale meaningful for conservation and restoration actions. Figure 1 depicts this framework overlain on a portion of the Detroit River. Figure 1. Framework of planning units (10-ha hexagons) used in the WLECCV. The northern reach of the Detroit River - including portions of MI and ON is depicted for reference.