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37 <br /> Non-barrier Roads <br /> r <br /> � Streams <br /> A; habitat <br /> Suitable habitat patch <br /> Suitable habitat<patch size <br /> ..a s Unsuitable habitat <br /> Potential crossing <br /> (unsuitable habitat) <br /> _7 <br /> Barriers <br /> Barrier road <br /> t'\ % ` Developed area <br /> Open water <br /> Figure 10.A portion of the cost surface for the Dry-Wet Hardwood and Mixed Forests guild in the project area. <br /> Unsuitable habitat areas, including potential crossing locations, are assigned a cost of I distance unit. Suitable <br /> habitat(non patch)areas are assigned a cost of 1/3 distance unit, to reflect the lower cost and species'ability to <br /> move greater distances through suitable habitat.In the modeling approach for this project, movement proceeds from <br /> the edge of one habitat patch to the edge of another patch, such that there is no movement cost associated with the <br /> area occupied by habitat patches.Non-barrier roads and streams are shown for context. <br /> Analysis and interpretation <br /> Using a combination of tools and scripts from ArcGIS 10.4 (ESRI 2014), GeoHAT(Fay 2012),Tuttle's <br /> custom toolbox for this project(Tuttle unpublished), and NetworkX(Hagberg et al. 2008), a network of <br /> habitat patches and least cost corridors was identified for each guild. The relative connectivity <br /> importance value was then calculated for each corridor segment(edge,not to be confused with habitat <br /> edge)between two habitat patches. We used the cost-weighted edge betweenness centrality(EBC)metric <br /> (NetworkX Developers 2019)in NetworkX to represent connectivity importance value for corridor <br /> segments. EBC represents the proportion of least cost paths between all patches in the connected network <br /> that"travel"through a particular corridor segment, and the value ranges from 0 to 1 (Wade et al. 2015). <br /> To assign a connectivity importance value to each patch,the maximum EBC value for all corridor <br /> segments connected to the patch was assigned to the patch. In this way,the most important patch-corridor <br /> pathways for overall landscape connectivity were mapped. <br /> Species occurrence data for one indicator species in each guild(Figure 11)were used to develop a <br /> subnetwork of corridor connections between species occurrences,and the EBC-based connectivity <br /> importance values for these species observation networks were used to refine the priority habitat network <br /> for the project area. Specifically,the maximum connectivity importance value for either the habitat-only <br /> network or the species observation network was applied for each corridor segment and habitat patch. <br /> 24 A Landscape Plan for Wildlife Habitat Connectivity <br />