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Beaver Reintroduction in the Absaroka- Beartooth Wilderness. Greater Yellowstone Ecosystem. Absaroka- Beartooth Wilderness. (1,475 sq. miles). Release Areas. Buffalo Creek. Hellroaring Creek. Stillwater River. Eagle Creek. Slough Creek. Project Origin.
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Beaver Reintroduction in the Absaroka-Beartooth Wilderness
Greater Yellowstone Ecosystem Absaroka-Beartooth Wilderness (1,475 sq. miles)
Release Areas Buffalo Creek Hellroaring Creek Stillwater River Eagle Creek Slough Creek
Project Origin Abundant habitat devoid of beaver (Early 1980’s)
Wilderness Reintroduction Requirements • Positive affect • Unable to recolonize • Sufficient habitat • Extirpation by humans • Historically present – currently absent
Preparatory Documents • Minimum tool – Wilderness character • NEPA – Effects and public input • BA & BE – Protected species
An Ecosystem Engineer Riparian habitat enhancement
Sufficient Habitat 20 miles: 1st-3rd order streams
Beaver abundant until 1950’s
Beaver absent in 1985- but evidence of past occupancy
Cause of demise: • Trapping • Tuleremia • Willow decline
Relocation constraints : - Family groups - Early fall release
What can we learn? Management actions as investigations
Inventory Example: Frenchy’s Meadow Dams Lodges Bank Lodges Caches
Quantification of Physical Variables • Stream sinuosity • Stream width and depth • Sandbar distance • Willow canopy • Distance to confluence
Results 1986-2010: • Carrying capacity reached – year 2000 • Colonies = 1.33/ km • Willow and standing water >15%
Carrying Capacity Model: Colony success correlated with: - Greater stream sinuosity and depth - Less distance to secondary channel - Fewer gravel bars Colony success not correlated with: - Willow canopy