The Hub Conservation Area - Montanans 4 Safe Wildlife Passage

Background: The HubConservation AreaProject Boundary and DescriptionThe regional conservation area called the Hubin this report is the interface between thedensely forested, mountainous landscape ofnorthwestern Montana and the basin and rangegeography of southwestern Montana. Thenorthern boundary of the Hub as defined in thisreport extends from the foothills north of theLittle Belt Mountains, extending west across theContinental Divide just south of the ScapegoatWilderness, runs north of the Blackfoot Valley,across the Swan Mountains and the lowerend of Seeley Lake, and through RattlesnakeWilderness south of the Mission Mountainsnorth of Missoula. The southern boundary ofthe Hub extends from the Boulder River east ofthe Absarokas, across the Paradise Valley andthe Gallatin Crest, encompasses the GallatinCanyon and the Spanish Peaks of the MadisonRange. The boundary then turns slightly northacross the southernmost reaches of the GallatinValley, before continuing west across the northend of the Tobacco Roots and includes part ofthe Highlands, Homestake Pass, includes theBig Hole River in the north end of the Pioneers,and the north end of the Big Hole Valley beforeentering into a heavily forested region nearLost Trail in the Beaverhead Mountains, beforeending just east of the Selway-BitterrootWilderness. The eastern boundary is moreclearly defined geographically, skirting theeastern foothills of the Little Belt Mountainsand the Crazy Mountains. The western boundaryis more artificial, but essentially follows theridgeline of the Bitterroot Mountains west of theBitterroot Valley.There are several distinct mountain regionswithin the Hub, with habitat types stronglyinfluenced by the presence of the ContinentalDivide, which runs north-south just east ofthe “center” of the area defined as the Hub.The northern edge of the Hub is much more ofa continuous forested, mountainous complexwhere the southern edges of the Rattlesnake,Swan, and Mission mountains converge. Thisarea is known as the Cabinet Yaak ecosystem inthe west, and the Northern Continental Divide(NCDE), or “Crown of the Continent” ecosystemin the eastern half of the complex. The easternboundary of the Northern Continental Divide/Crown of the Continent ecosystem, where themountains meet the plains of central Montana,is known as the Rocky Mountain Front. It is thevery southern end of the Rocky Mountain Front,the NCDE, and the Cabinet Yaak ecosystemsform the northern border of the Hub.The Continental Divide region of the Hub runssouth out of the Scapegoat Wilderness. In thisarea, the more isolated formation of mountainranges begins to define itself as the BoulderMountains. These mountains run south, endingjust north of Butte, Montana. The ElkhornRanges and the Bull Mountains are small rangesjust slightly separated from the main Boulderrange by narrow valleys.In the southern-central half of the Hub,mountain ranges become better defined, withbroad intermountain valleys; graduating to thetrue basin and range geography of the HighDivide region to the south. An anomaly is inthe southeastern and southwestern corners ofthe Hub, where again the landscape becomesmore mountainous with narrow valleys. In thesoutheast corner this is the northernmost extentof the Greater Yellowstone ecosystem (GYE),and in the southwest it is the Salmon-Selwayecosystem.The Eastern HubEast of the Boulder Mountains, the broad Helenavalley is indicative of true basin and rangegeography. The town of Helena lies betweenthe Boulder Mountains and the Big Belts. TheBig Belt Mountains and Bridger Mountains forma long, narrow series of mountains extending ina graceful slightly backwards C-shaped curve.The Big Belts, in the northern half, extend fromwhere the Missouri River enters the HelenaValley and extend to just south of Canyon FerryLake. There is a lower series of hills and creeksbetween the Big Belts and Bridger’s, which skirtthe eastern edge of the very broad GallatinValley and city of Bozeman, Montana. The verywestern extent of the Gallatin Valley is wherethe confluence of the Madison, Jefferson, and20