The Hub Conservation Area - Montanans 4 Safe Wildlife Passage

Silver StarSpeciesGeographic BoundaryThe linkage area is bounded by theTobacco Root Mountains on the east, theHighlands Mountains on the west, andconsists primarily of the Jefferson Rivervalley between Ironrod Bridge on Highway41 and Fish Creek south of Whitehall.Importance of Linkage AreaThis linkage area is another steppingstone for potential large carnivoremovement from the Greater Yellowstonearea through the Gravellies and TobaccoRoots to the “Central Linkage Ecosystem”of the Highland-Elkhorn-Boulder ranges.The most undeveloped portion of theSilver Star linkage is between Waterlooand Silver Star.Mountain ranges connected in thislinkage: Tobacco Root Mountains andHighland MountainsEcological SettingOpen alluvial fans and river terraceson the east side of the Jefferson Rivervalley are predominantly dry blue grama(Bouteloua gracilis) and needle-andthread(Stipa comata) grasslands. Somecenter pivot irrigation systems havebeen developed on these terraces forhay production. Cottonwood (Populusangustifolia) and willow (Salix spp.)riparian communities dominate theriver corridor. Irrigated pasture and hayland is interspersed throughout most ofthe river bottom. Small subdivisions,residences and farm buildings occurthroughout the linkage, increasing indensity from Ironrod Bridge northwardtoward Whitehall. The rugged HellsCanyon watershed and Bulldog Mountainare the key topographic features thatare the closest to the Tobacco Roots thatattract wildlife movement from the east.164Highway 287 and a seldom-used railroadspur line bisect the linkage parallel tothe river. The west side of the valleygrades into the rocky granitic foothills ofthe Highland Mountains where vegetationis dominated by scattered stands ofDouglas-fir (Pseudotsuga menziesii),limber pine (Pinus flexilis), and RockyMountain juniper (Juniperus scopulorum),and Wyoming big sagebrush (Artemisiatridentata wyomingensis), blacksage (A. nova) and curlleaf mountainmahogany (Cercocarpus ledifolius) shrubcommunities.WildlifeWildlife use in the Jefferson River valleybetween the Tobacco Root and HighlandMountains is constrained by the amountof human development and highwaytraffic that is present. The river corridorsupports numerous sandhill cranes,waterfowl, songbirds and raptors, andis a major flyway for spring and fallmigrations of sandhill cranes, snow geeseand swans.Wolves and wolverine: The linkageprovides a likely corridor for wolf andwolverine movement between two areasof potential habitat in the Tobacco Rootsand habitats further south and east,and the Highlands and habitats furthernorth /west. Neither of these areas isreally large enough to provide yearlonghome ranges for either species, althoughpotential wilderness designation in theHighlands and Tobacco Roots would securehigh quality habitat.Moose are present yearlong in theJefferson River bottom and along the eastfront of the Highlands, particularly in BigPipestone Creek.White-tailed deer are overly abundantthroughout the Jefferson River corridor.