Monture Creek, a 4th order tributary
stream to the middle Blackfoot River, originates in a roadless watershed bordering the
western and southern edges of the Bob Marshall Wilderness. It flows 24 miles,
entering the Blackfoot River at river mile 44.2. Its base flow measured 44.2 cfs at
stream mile 0.4 on August 8, 1989. After leaving the mountains, the lower reaches
of Monture Creek meander in a slightly entrenched channel confined by knob-and-kettle
topography. Monture Creek is a laterally moving sand, gravel and cobble bottom
stream, characterized by riffle/pool habitat typical of a C4 Rosgen stream
type. Rates of lateral movement are largely a function of riparian vegetation for
this stream type.
Land uses along Monture Creek consist
primarily of livestock production. Much of the riparian area in lower Monture Creek has
been cleared, grazed intensively or damaged by livestock wintering; many of the large
conifers from the lower riparian area have been harvested. These activities have
impacted stream banks and reduced stream complexity in the lower 7 miles of the stream. 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. Monture Creek ranked 1 of 83 streams
From 1990 to 1998,
riparian livestock management improvements have been implemented on 9.3 miles of the
mainstem of Monture Creek including 6 miles of bull trout spawning and staging
areas. This represents 80% of the mainstem located on private lands. In 1997,
a cooperative stream restoration project, focusing on the placement of large woody debris,
was completed for two sections of stream totaling over three miles of channel.
Log vane structure that provides
in-stream habitat and reduces bank erosion.
Log J-hook vane.
Project monitoring focuses on three
types of information:
1) stream habitat surveys, focusing on
instream woody debris placement
2) bull trout redd counts
3) juvenile bull trout monitoring at 5
long-term sampling locations
In 1999, a mark-recapture
fish population survey was established in lower Monture Creek. The sample was divided into
two sections: an upstream section which had received no restoration activities other
than livestock management improvement and an adjoining downstream section which received
livestock management improvements and habitat restoration through the instream placement
of large woody debris. Separate finclips were used to identify fish for each section.
Total trout densities in the upstream control section were 60 fish/1,000 feet compared to
106 fish/1,000 feet in the downstream restored section. The combined densities of native
fish were approximately three times higher in the restored section compared to the
In the fall of 1999,
following the initial survey, we completed the restoration of the upstream section; this
project included riparian fencing and instream woody debris placement. Before this
project, the frequency of instream large woody debris in the untreated reach was 6.1 large
woody stems/1,000 feet compared to 18.1 stems/1,000 feet in the lower treated reach. The
population survey, for both sections combined, estimated a total trout density of 95.7
fish/1,000 feet for 2001 compared to 73.9 fish/1,000 feet in 1999. Bull trout numbers
increase from 22 fish/1,000 feet in 1999 to 54 fish/1,000 feet in 2001.
Bull trout use Monture Creek as a
migration corridor, pre-spawning/staging area, spawning, rearing and thermal refuge.
Radio-tagged bull trout migrate an average 50 miles from the Blackfoot River to previously
known spawning areas, and remain for nearly three months before spawning in late
September. One radio-tagged bull trout spawned in Monture Creek three consecutive
years. Because it was 28 inches when it received its transmitter, it is likely it
had also spawned in previous years.