Session Name: Upper Columbia River Redband Trout
Presentation Title: Stream Habitat Assessment and Rehabilitation Planning for Redband
Rainbow Trout using an Ecosystem Diagnosis and Treatment Model
Presenter Name: Ryan Klett
All Authors, affiliations, phone number, email:
Ryan Klett, Colville Confederated Tribes, 509-634-6401, ryan.klett@colvilletribes.com
Eric Doyle, ICF International, 206-801-2811, eric.doyle@icfi.com
Jason McLellan, Colville Confederated Tribes, 509-209-2418,
jason.mclellan@colvilletribes.com
Abstract: Stream habitat assessment and rehabilitation project planning at watershed and
subbasin scales (101-104 km2) can be a complex process. The Colville Confederated Tribes are
utilizing an Ecosystem Diagnosis and Treatment (EDT) model to provide unique context to a
dataset containing over 100km of longitudinal stream habitat inventory during the assessment,
prioritization and planning phases of habitat rehabilitation for adfluvial Redband Rainbow Trout
in tributaries of Lake Roosevelt, WA. This approach is already being tested in subbasins of the
Columbia River containing anadromous O. mykiss with promising results. Existing EDT
biological benchmarks and species habitat rules for anadromous Upper Columbia O. mykiss were
adapted to reflect local expressions of Redband Rainbow Trout life history and differences in
habitat selection across multiple life history stages. Identification and prioritization of
rehabilitation projects has been significantly enhanced by the synergy between standard methods
of habitat assessment and EDT model results. This methodology has potential to enhance habitat
assessment and rehabilitation prioritization processes for any resident salmonids with at least a
partially migratory life history component.
Student Presenter? (Work being reported was completed while a student): No
Presentation Type: Oral presentation only
Modification of Biological Benchmarks and Species/Habitat Rules:
See the Life History Model tech memo for overview of benchmark changes.
Rule modifications:
Life Stage(s)
Incubation
Survival Factor
Channel Stability
Level 2 attribute
Bed Scour
Resident and inactive
juvenile rearing
Flow Conditions
Backwater Pools
Beaver Ponds
Inactive juvenile rearing
Habitat Diversity
Large cobble riffle
Beaver ponds
Floodplain habitats
Action
Increased incubation
sensitivity to reflect
shallower redd depth
Moderates effect of
degraded flow
conditions on survival
Moderates effect of
degraded habitat
conditions on survival
Examples – Incubation sensitivity to bed scour. X-axis is Bed Scour Level 2 rating (see the attribute rating
guidelines), y-axis sensitivity is the proportional reduction in egg survival relative to benchmark
conditions. Blue curve is redband sensitivity, red curve is steelhead. Rationale provided in following
table:
Parameter
Steelhead minimum to top of egg
pocket
Depth
(cm)
10
RBT mean to top of egg pocket
15-20
Mean to bottom of egg pocket (both
species)
23.4
Data Source
California coastal steelhead observations, Needham and Taft
1934 and Shapovolov and Taft 1954 - Source: Devries 1997
Hooper 1973 (10 observations of rainbow trout, RFL 30-36 cm),
Hobbs 1937 (4 observations of rainbow trout) - Source: Devries
1997
Derived by adding scaled difference b/t steelhead redd size
(average 1.78 m^2: Gallagher and Gallagher 2005) and redband
trout (average 1.19 m^2: Holocek and Walters 2007) to
minimum egg pocket depth. Scaled difference = 13.4 cm (206.7).
Forecast max RBT redd depth
Steelhead mean to bottom of egg
pocket
25
Forecast based on predicted mean
30
Miller 1985 - Source: Devries 1997
Steelhead max
<31
Wydowski and Whitney 1979 - Source: Devries 1997