
Ashby Creek is a second order tributary
stream to Camas Creek entering at mile 0.5 in the Union Creek Watershed. The upper reaches
flow predominately through forested areas including Plum Creek and Bureau of Land
Management properties before entering private ranchland near mile 3.0. Stream gradient
ranges from 960 feet/mile in the headwaters to 90 feet/mile in lower reaches. In 2000, we
established four survey sections--three on the mainstem and one on the lower East Fork of
Ashby Creek.
At the two upper survey locations, the
riparian community consists of conifer woodland with alder and grass/sedge species in the
understory. At stream mile 3.0, the stream enter a ponderosa pine, aspen and meadow
environment with a well-manged and healthy riparian area. Near the lower survey site (mile
1.0), the riparian community consists of sparse grasses with an overstory of suppressed
alder. Our surveys showed Ashby Creek's dominant fish species was westslope cutthroat
trout with densities increasing in the upstream direction.
In order to prioritize restoration
resources, we developed a fisheries-based restoration priority scorecard, based on
biological, social and financial considerations, for 83 impaired tributaries of the
Blackfoot River. Ashby Creek ranked 49 of 83 streams surveyed.
Fisheries related impairments, located
in the middle and lower reaches, include 1) irrigation (fish passage and dewatering), 2)
channel alterations, 3) lack of complex fish habitat (instream wood), 4) excessive
livestock access to riparian areas, and 5) elevated sediment from road drainage.
The bulk of lower Ashby Creek is in one
large private ranch in the Potomac Valley. The ranch has agreed to address the above
mentioned fisheries impairments, as well as restoring a large scrub/shrub riparian wetland
and entering into a conservation easement to protect the ranch and its fish and wildlife
values. |