The Hub Conservation Area - Montanans 4 Safe Wildlife Passage

irds). This step was repeated for conservationthreats (e.g. fencing, roads, subdivision, socialintolerance) and conservation opportunities(e.g. conservation easements, conservationmindedlandowners). Conservation threats(CT) were rated from 1 (low threat) to 10 (highthreat) and conservation opportunities (CO)were rated from 1 (low opportunity) to 10 (highopportunity). Linkages identified for EQ, CT,and CO could overlap, but were not required todo so (i.e. some linkages were given ratings forall three categories while others were given onlyone or two).Several biologists believed that the linkagemap that we were working to create should beturned on its head; urban areas should be excludedand the remaining land should be consideredpossible linkage habitat. Bears will gowhere we will allow them, they argued, andconsideration of all of western Montana as connectivityhabitat has been demonstrated by theState’s grizzly bear management plan for westernMontana. For the purposes of the PriorityLinkage Assessment, we chose to identify andfocus on the best habitat and opportunities forwildlife movement within the region so that asthe landscape changes, restoration and protectionis focused in priority locations to ensurelong-term opportunities for movement amongthe region’s ecosystems.After the interviews, experts’ areas of expertiseand identified linkages were digitized inArcGIS 9.2 (ESRI 2007). Each distinct linkagewas assigned a unique number, i.e. linkagesidentified by multiple experts were digitizedonly once and assigned only one number.Linkage- and expert-specific data were enteredinto a Microsoft Access database (MicrosoftWindows XP Professional 2002). A record wascreated for each linkage identified by an expert.Hence, a linkage identified by five experts hadfive separate records in the database, eachcontaining, when applicable, ratings and textualinformation for wildlife species, EQ, CT, and CO.The ratings assigned by the experts were usedto rank the linkages; the ratings and textualinformation will be linked to the digitizedpolygons in ArcGIS.Deriving linkage scoresThe experts’ ratings were averaged andcombined to produce an overall score (L) foreach linkage using the following equation:Eq.1where n (EQ, CT or CO) is the number of ratings. Inthe equation, EQ is weighted with a powerof 11 to ensure that even the lowest value ofEQ (i.e. “1”) would outrank any stand-alonevalue of CT or CO. Hence, the overall linkagescore is driven by the linkage’s ecological valuewith bonuses given for identified threats oropportunities. Linkages that were identified byan expert but not rated (i.e. the expert wasuncomfortable assigning a ranking) were notincluded in the analysis.GroupingMany of the expert-identified linkages overlapped,resulting in a cluttered, almost indecipherablemap. To make the map more usableand to eliminate duplicate linkages with thesame function (e.g. multiple linkages on Interstate90), we grouped the linkages into Majorlinkages using the experts’ descriptions of theconnectivity and our own knowledge. We averagedthe ratings of “sub-linkages” that made upthe major linkages to produce an overall MajorLinkage Score (MLS) using the following equation:Eq.2where Li are the scores of the sublinkagesincluded in the Major linkage and nLi is thenumber of sublinkage scores averaged for theMajor linkage.27