This layer was originally developed by a team of FS and FWS biologists. Their delineations were based on the grizzly bear home range sizes from the Cabinet-Yaak Grizzly Bear ecology study (Kasworm and Manley 1988). Each BMU was to approximate the size of a female grizzly bear home range and include all seasonal (spring, summer, fall, winter den) habitat components. Boundaries were to be easily identifiable on the ground so they follow hydrologic boundary to the extent possible. Boundary adjustments were last made in 1997 to match adjusted watershed boundaries.

Corrected BMU 8 with boundary change approved by IGBC subcommittee along Lolo NF, changed approximately 20 acres. 4/4/2013

Addition of NCDE SubUnits to NC-1 BMU.

NCDE stands for North Continental Divide Ecosystem. The Kootenai National Forest is part of two grizzly bear recovery zones. We have the bulk of the Cabinet-Yaak recovery zone but share parts of it with neighboring forests. We only have a small part of the North Continental Divide Ecosystem, with the bulk of it being on the Flathead National Forest and several other forests also having pieces. The Cabinet-Yaak recovery zone plus some surrounding area is also referred to as the CYE, or Cabinet-Yaak Ecosystem.

Edited BMU (code) to NCDE-1. Included addition of small portion of Stryker Lake BMU, Stryker subunit as derived from EDC SDE S_R01_FLT.NcdeSubUnit (2/28/13). Added attribute SUBUNIT_NAME and recalculated acres in GISACRES. As this was the first time this feature class had had acres recalculated since it was imported from coverage format there was a small gain in acreage (from the old ArcAcres field). Also eliminated the empty polygon of non-BMU land (old Troy BORZ). 3/1/13