Introduction

The Colville Confederated Tribes (CCT) Resident Fish RM&E project is a Columbia River Fish Accord project that began in 2008. The primary goal for the Resident Fish RM&E Project is to conserve, enhance and restore native fish populations in the blocked area above Grand Coulee Dam in Lake Roosevelt and its tributaries, and where appropriate provide opportunities for subsistence harvest by the Colville Tribal members and recreational anglers.

The current work of the RM&E project will focus on the protection and conservation of redband trout populations on the Colville Confederated Tribes Reservation, with a focus on the Sanpoil River. Rainbow trout are a focal species in the Sanpoil Subbasin under the Intermountain Province Subbasin Plan (IMP) due to their recreational value as a sport fish and their cultural significance to the CCT (Gillin and Pizzimenti 2004). The Columbia River redband trout are a subspecies of rainbow trout native to the Columbia River drainage east of the Cascade Mountains as far as barrier falls on the Snake, Spokane, Pend Oreille, and Kootenai rivers (Allendorf et al. 1980; Behnke 1992; Lee and McLellan 2011). Effective fisheries management of redband trout requires an understanding of population structure, complex historical management activities, geography, and life history strategies (McCusker et al. 2000; Spidle et al. 2003; Spruell et al. 2003; Small et al. 2007).

Project Location

The Sanpoil River is located in North Central Washington. The river flows in a north to south manner from Republic, Washington to its terminus at Lake Roosevelt. Total stream length is approximately 113 km and drains approximately 2,590 square km. Sixty km of mainstem river flows through the Colville Reservation, in addition to long distances of several tributaries including Iron, Louie, N and S Nanamkin, Bridge Creek, Bear Creek, 13 Mile, 17 Mile, 23 Mile, 30 Mile, Gold creeks and the West Fork Sanpoil River. The stream bottom is mostly gravel and small cobble with lesser amounts of boulder, rubble and silt. Fifty-five percent of the tributaries that were once perennial are now intermittent (Gillin and Pizzimenti 2004). The river is surrounded by mountains and has a valley approximately one mile wide. Land use practices in the basin include agriculture, logging, mining, and cattle grazing and the associated  impacts can be observed in the Sanpoil through cemented sediments. 

Prior to the construction of Grand Coulee Dam, the Sanpoil supported a large run of summer and fall Chinook and was famous for its summer steelhead runs. Today, the river contains mostly rainbow trout, eastern brook trout Salvelinus fontinalis, mountain whitefish Prosopium williamsoni and kokanee Oncorhynchus nerka. Historical stocking mainly consisted of coastal rainbow trout, redband rainbow trout and eastern brook trout (Gillin and Pizzimenti 2004).

The specific study area for the proposed work is the mainstem Sanpoil River on the Colville Reservation along with the 8 tributaries listed in Figure 1. The eight focus tributaries for this study include Iron, Louie, Bridge, S Nanamkin, N Nanamkin, 21 Mile, West Fork Creek, and Gold Creek (Figure 1).

Figure 1. Map of Columbia River, showing the Sanpoil River with key tributaries in the Sanpoil River basin.

Status of Rainbow Trout in the Sanpoil

The CCT has been collecting baseline information on the rainbow trout in tributaries to the Sanpoil River since 1990 through the Lake Roosevelt Rainbow Trout Habitat Improvement Project (1990-018-00). Much of the focus has been towards identifying and improving habitat while minimally assessing the abundance of adult and juvenile migratory (adfluvial) fish in relation to habitat improvements. Detailed information on the population dynamics has never been collected especially relating to life history characteristics. Some of the difficulty in understanding the ecology of rainbow trout in this basin is due to the varied life history types thought to exist. Some adult fish migrate into the drainage from Lake Roosevelt (in both the spring and summer) to spawn while others are thought to be resident in the drainage year round. Some juvenile rainbow trout are known to migrate out of the drainage into Lake Roosevelt in the spring, but others may migrate in the summer or fall or may reside in the drainage all year. 

Some research has been conducted on migratory populations of rainbow trout that use the drainage. Spawners return from Lake Roosevelt to tributaries between ages 3 and 6 years. Upstream traps have been used to examine these fish; these data indicate that spawning populations have fluctuated from less than 13 individuals in 1997 (5 tributaries surveyed) to 428 individuals in 2007 (6 tributaries surveyed) (Sears 2006). Fall escapement surveys conducted from August to November (kokanee monitoring) indicate that rainbow trout migrating upstream into the drainage range from 10-15 individuals per year (Wolvert and Nine 2010). However the research efforts mentioned above do not supply a complete picture since data are not available from periods when traps were not operated or when surveys were not conducted. In addition, no surveys have been conducted on the mainstem Sanpoil River. 

Adult rainbow trout abundance is thought to be low compared to the number of miles of habitat available in the Sanpoil Basin. To alleviate this problem, the Tribe has conducted habitat improvements to some tributaries and removed barriers. Specifically, passage and habitat enhancements have been conducted on Louie, Iron, South Nanamkin, North Nanamkin, Bridge, Thirty Mile, Thirteen Mile, Twenty-Three Mile, Gold, and Roaring Creeks. Rearing habitat remains restricted due to intermittent flows in the lower reaches of several of the streams that have spawning habitat. In recent years work to improve flows, reduce sediment delivery and increase water retention in the individual watersheds has included road abandonment, riparian plantings, cattle exclusion fencing, and relocation of beaver into upper reaches of the watersheds.

Unfortunately, little is known about the populations that reside the entire year within the drainage. A few populations have been observed in Bridge Cr., West Fork Sanpoil and Gold Creek during fall habitat surveys. It was determined that the Bridge Creek fluvial population, above a waterfall, was genetically pure (Sears 2006). Although, some spawning surveys have been conducted to identify spawning areas, these were done only in the lower reaches and were directed at the adfluvial population that is the focus of the LRHIP. Additionally, high velocities and high turbidity limited any observations of redds during surveys in the lower tributaries and Sanpoil mainstem (Sears 2006).

Juvenile rainbow trout survival and abundance is also not well understood within the basin.  Surveys of juveniles in select tributaries suggest that their abundance is low. In the spring of 1998, 19 adult rainbow trout moved upstream into North Nanamkin Creek. During the next spring, a total of 96 juveniles were captured in downstream traps (Jones 1998). Six segments of Gold Creek (a tributary to West Fork Sanpoil) were electro-fished in the fall of 2004 and a total of 1,134 juvenile rainbow trout were captured. During the following spring of 2005 a screw trap was placed at the mouth of the West Fork Sanpoil that captured only 119 juveniles; additional juvenile traps were set in the stream the same year and captured 606 juvenile fish (Sears 2005). Three distinct age classes were present (young of year, one year “parr” and two year “pre-smolt”) and consisted mainly of age 1 fish. Environmental factors and trap efficiencies limited an accurate assessment of the numbers of fish in the drainage, when they migrate, or how many migrate when. Juveniles may migrate in late fall or early spring before traps are set. Juveniles have been documented migrating into mid-August (Sears 2000) however recent surveys have been limited to June due to low flows and occasionally extremely high flows. Attempts were made to determine egg to fry survival with red caps but high flows blew the traps out and future attempts were abandoned.

Intermittent streams such as N. Nanamkin and S. Nanamkin provide quality spawning habitat for adults, however nursery habitat becomes limited by mid to late summer as flows decrease or go subsurface. Juveniles are then subjected to migrating to the Sanpoil River to survive.

Management objectives for the Sanpoil River are to increase adfluvial rainbow trout abundance to support recreational and subsistence harvest (i.e., 1 fish/hr) while maintaining a genetically diverse and naturally reproducing population (CCT Fish and Wildlife Management Plan, 2007). Adult spawner abundance objectives have never been determined because a specific stock assessment project has never been initiated. The Tribe suspects that the bulk of the population is adfluvial with some resident fish. Resident fluvial populations have been found above barriers in many of the tributaries, however these were not the focus of the habitat improvement project, therefore little data has been collected on these populations beyond genetic analysis.

Two genetically distinct subspecies of rainbow trout have been identified within the Sanpoil Subbasin (Small and Dean 2006, 2007). Redband trout are native to the drainage, while coastal rainbow trout have been introduced to the area (Gillin and Pizzimenti 2004). Native redband may be genetically similar to the native, steelhead populations that were once abundant within the upper Columbia River system (Leary 1997; Gillan and Pizzimenti 2004). Although genetic testing has revealed introgression among subspecies, genetically pure redband trout still exist above barriers (Leary 1997, Small and Dean 2006, 2007). Young et. al. (2008) indicated that greater than 75% of the adfluvial rainbow trout in the Sanpoil system are non-hybridized redband stocks.

In order to properly manage the redband population for protection and enhancement in the Sanpoil Subbasin, an understanding of population dynamics is necessary along with an understanding of survival trends during key life-histories (Anchord et al. 2007; Baltz et al. 1991). During the next five year cycle (2013-2017) the Resident Fish RM&E project has the primary objective of monitoring trends in abundance of fluvial and adfluvial redband rainbow trout in the Sanpoil River.

Data currently being gathered on redband adult life histories within the Sanpoil basin have identified three primary life history strategies (fluvial, fluvial-adfluvial and lacustrine-adfluvial) (Northcote 1997). Fluvial populations (or resident populations) are documented above barriers and do not migrate extensively within their home range, however a fluvial populations for the mainstem Sanpoil River is still unknown. The fluvial-adfluvial population (migratory cycle between streams or rivers and their tributaries) has been documented within the Sanpoil River drainage, however specific migratory cycles are still not fully understood. The lacustrine-adfluvial population (migrates from Lake Roosevelt into the Sanpoil River) has been found to contain three "components" which include a spring, summer, and fall run. This complex life-history has made this population difficult to understand and study (Baltz et al. 1991; Holecek and Walters 2007). Studies on overwinter ecology are ongoing, with results expected in 2013.

Preliminary data also indicated redband trout begin to out-migrate in February, with the peak occurring in April and May. The majority of redband out-migrating ranged between 100 and 200 mm total length, and likely encompass two year classes. Aging using scale analysis is ongoing.

Management Questions

In 2010 the Colville Tribe began working with regional co-managers to develop a comprehensive plan to monitor the redband trout populations in the blocked area. The Lake Roosevelt co-managers developed the Lake Roosevelt Guiding Documennt (2009) that included goals and objectives for each of the primary managed species. In addtion, The Washington Department of Fish and Wildlife (Lee and McLellan 2011) developed a proposal to be used by the co-managers to develop redband stock assessment projects in their primary focus tributaries. It was envisioned this document would assist the co-managers with developing similar protocols so that data collected by multiple projects and entities would be compatible and comparable in the future.

This is the outline the CCT has used to develop the Resident Fish RM&E program to conduct stock assessments on redband trout in the Sanpoil River. The project plans to implement four primary tasks which include monitoring abundance, monitoring recruitment, monitoring harvest, and monitoring escapement to assist with management decisions. The development of a multi-year data set will enable managers to monitor trends over time and address potential limiting factors.

Monitoring Abundance (2014-2017): The CCT’s Lake Roosevelt Habitat Improvement Project (LRHIP) (1990-018-00) will conduct a baseline inventory of redband trout abundance in the Sanpoil River and primary tributaries during the summer of 2013. This inventory will assist the Habitat Project with prioritizing restoration projects, and provide the first data point for the RM&E project to monitor trends over time.

The RM&E project will conduct annual monitoring of fluvial redband trout via backpack shocking, using a two pass removal depletion method, July through September in the 8 primary tributaries. Sampling methods will be similar to the LRHIP and will include sampling in each of the 8 primary. The mainstem Sanpoil will be backpacked shocked if possible, or snorkel surveys will be conducted. All rainbow trout will be PIT tagged for further monitoring.

The primary objective will be to PIT tag as many rainbow trout as we can in order to accurately quantify the recruitment and harvest objectives listed below. However, the project will follow guidelines for backpack electrofishing described by the ISEMP (2008a), A field manual for electrofishing protocol of the Upper Columbia Monitoring Strategy. To determine the location and frequency of sampling, the Project will follow guidelines developed by the ISEMP (2008b), Selecting sampling sites within the ISEMP. The Project will select protocols developed for status and trend monitoring, which include generalized random tessellation stratified (GRTS) sample design (Stevens and Olsen 2003) to achieve a spatially balanced random sample. To determine the status, 5 rotating panels of 25 sites will be selected from the GRTS site list with one panel sampled each year for five years (Urquhart and Kincaid 1999). To determine trends in fish abundance, a single annual panel of 25 sites (or index sites) will be selected from the GRTS site list and sampled each year. After completion of the 5 year pilot program, a power analysis will be used to determine if enough sites are sampled annually to detect trends.  

Monitor Recruitment (2013-2017): The RM&E project will place a series of PIT tag arrays throughout the Sanpoil River basin to estimate recruitment. Fluvial and fluvial adfluvial populations will be monitored from PIT tag array systems set at the mouth of 8 primary tributaries. Two mainstem PIT tag arrays will be used to document timing of out-migration. Adfluvial populations will be monitored with a screw trap and the mainstem PIT tag array near mouth of Sanpoil River.

Recruitment (R) will be defined as the number of juvenile redband trout emigrating from their natal tributary into the Sanpoil River or Lake Roosevelt. Fisheries managers commonly monitor recruitment of anadromous salmonids (Seelbach 1993; Kennen et al. 1994; Thedinga et al. 1994; Newcomb and Coon 2001), however few studies have evaluated recruitment of native rainbow trout that exhibit a lacustrine-adfluvial potamodromous life history (Northcote 1969, 1962; Sears 2006; Nine 2007; Stroud et al. 2010; Lee and McLellan 2011).

Biological data including age, length and weight, collected from out-migrating juveniles will be used to estimate growth parameters. Age at recruitment will be determined from scale samples (Alvord 1954) using methods found in DeVries and Frie (1996). Length frequency distributions will also be developed for each tributary (Anderson and Neumann 1996). Growth parameters will be calculated using von Bertalanffy growth functions (Isely and Grabowski 2007).

Rotary screw traps have been used to sample downstream migrating salmonids in systems ranging from moderate sized streams to large rivers and over a wide range of discharges (Kennen et al. 1994; Roper and Scarnecchia 1996; Chaput and Jones 2004; Scace et al. 2007).  Screw traps are highly mobile so they can be moved relatively quickly if stream conditions become unacceptable. Rotary screw traps are designed to be relatively self- cleaning and resistant to debris loading (Scace et al. 2007), although daily maintenance may be necessary to ensure the trap is functioning properly. Trap site is limited by stream depth and minimum velocities. Minimum depth requirements are approximately 0.75 m for a 1.5 m trap and 1.25 m for a 2.5 m trap. Rotary screw traps should operate at a minimum of 5-6 revolutions per min (RPM) and water velocities of 0.8-2 m/s to work effectively (Volkhardt et al. 2007). If water velocity is insufficient to operate the screw trap effectively, an electric motor can be outfitted to ensure the trap makes a sufficient number of rotations (Volkhart et al. 2007; Lee and McLellan 2011).

Screw traps will be operated February through June, and again September and October, or as long as environmental conditions allow, and checked at least once daily to collect baseline data on emigration. Adjustments to operational time will be based on the results of the initial year.  If juvenile collections are productive enough that fish are becoming crowded or excessive mortalities occur, additional traps will be checked more often than once a day. All fish captured will be measured for fork length and weighed. Species other than redband trout will be released downstream of the trap. All redband trout will be scanned with a handheld passive integrated transponder (PIT) tag reader capable of reading FDX-B 134.2 kHz PIT tags. Unmarked redband that are large enough (>65 mm) will be implanted with a 12 mm FDX-B (full-duplex) 134.2 kHz PIT tag (Digital Angel Corp.) in accordance with the protocols outlined by the Columbia Basin Fish and Wildlife Authority (1999). Newby et al. (2007) found no short term effects from PIT tag injection on feeding or swimming performance in juvenile rainbow trout.  Fin tissue samples will be collected from each redband trout and archived for DNA analysis, and scale samples will be collected for age determination. Tagged fish will be placed in a holding tank or bucket with fresh stream water and appropriate aeration device to recover from the tagging process. Fish that appear healthy and show normal swimming activity will be transported far enough upstream to allow normal distribution of fish across the stream channel (Volkhardt et al. 2007). For recaptured redband trout, tag number will be recorded and the fish will be placed in a separate holding tank for a short observation period to ensure the fish is healthy enough for release. Fish will be released far enough downstream to ensure they are not captured again in the trap (methods from Lee and McLellan 2011).  

A PIT tag detection array will be operated in concert with the juvenile traps. A PIT tag detection array will be used at each trap location to estimate trap efficiency. The PIT tag array will consist of a transceiver and antenna constructed similar to that described by Bond et al. (2007). A bank of rechargeable 6 volt batteries will provide power for the array. An Allflex fish interrogation system (OEM 840029-001), which is a modified panel reader module, will serve as the transceiver and will transfer PIT tag numbers to an Acumen Data Bridge SDR2-CF serial data recorder via an RS-232 cable. The data logger will store PIT tag numbers on a Compact Flash (CF) card that can be removed and downloaded to a computer. Allflex technology was chosen because of economical considerations in addition to the versatility of being able to detect both full duplex and half-duplex tags. The array will be constructed at an area that allows for antennae to span the width of the stream in order to maximize PIT tag detection efficiency. If the stream is too wide for one antenna to span, multiple antennae may be used cover the entire transect. In areas where one or more antennae are not able to span the entire stream width, efforts will be made to direct fish through the PIT tag detection array, thereby improving path efficiency (Zydlewski et al. 2006). This can be done with the construction of a weir or fence. Utilizing multiple PIT tag detection arrays at each trap location will maximize detection efficiency and then determine direction of movement (Lee and McLellan 2011). 

Stream discharge data will be acquired from the United States Geologic Survey (USGS) gage station 12434590 located on the Sanpoil River near Keller.

The PIT tag detection array will be used to validate screw trap efficiency by recording individual marked juvenile redband trout that pass the trap without being caught. PIT tag detection arrays have been used to monitor migration and movement patterns of PIT tagged salmonids at hydroelectric facilities and in natural streams (Connolly et al. 2008; Zydlewski et al. 2006; Axel et al. 2005; Bryant and Lukey 2004; Lee and McLellan 2011). Detection efficiency has been shown to vary with the number, type, and arrangement of the antennae arrays as well as in varying environmental conditions (Connolly et al. 2008; Horton et al. 2007; Zydlewski et al. 2006). PIT tag detection efficiency estimates will be conducted for each array under a variety of discharge regimes and will be used for both upstream and downstream movement (Fuller et al. 2008). Detection efficiency will be applied to estimates for recruitment and escapement to account for undetected individuals. Trap efficiency will be calculated using the equation suggested by Volkhardt et al. (2007).

Monitor Harvest (2013-2017): Managing healthy fish populations requires a basic understanding of the contribution to the recreational creel. Identifying overexploited stocks is the first step in implementing conservation, enhancement, and restoration measures (Lee and McLellan 2011). Recreational creel surveys are commonly accepted as a method to monitor recreational fisheries and are used broadly by fisheries managers in Washington State (Hahn et al. 2000).

A recreational creel survey has been conducted on Lake Roosevelt by the Lake Roosevelt Fisheries Evaluation Program (LRFEP; BPA Project 1988-063-00 and 1994-043-00) since 1988 to evaluate harvest, effort, and economic value of the fishery (Peone et al. 1990). The current recreational creel survey is a cooperative effort of the Spokane Tribe of Indians (STI), Colville Confederated Tribes (CCT) and Washington Department of Fish and Wildlife (WDFW) and extends from Grand Coulee Dam (RKM 959) to China Bend (RKM 1164) (Scofield et al. 2007). The area covered by the current creel survey encompasses more than 240 rkm (including the Spokane Arm), and more than 25 access points (Lee and McLellan 2011).  The RM&E project will use two creel surveys to monitor harvest impacts to Sanpoil River redband trout.

The fluvial population found in the mainstem Sanpoil River will be monitored through a 7 month access point creel survey (May – Nov) to estimate angler pressure and harvest within the river. Methods described by Malvestuto (1996) will be used for conducting roving and access site angler surveys.

The current recreational creel survey covers the majority of the area available to adult redband trout above Grand Coulee Dam and will provide the best opportunity to monitor select redband trout populations in Lake Roosevelt and the Sanpoil River. Coordination with LRFEP will facilitate data collection on redband trout harvest in Lake Roosevelt. The LRFEP, during this five year categorical review, has proposed an increase in creel effort to ensure higher probabilities of detecting wild fish that have been PIT tagged in the harvest. Clerks will continue to record biological data on each fish encountered, including species, total length, weight, and any existing marks (i.e. fin clips, tags, fin deformities) to identify origin. Creel clerks have been equipped with hand held PIT tag readers and scan all wild (non-adipose fin clipped) rainbow trout for the presence of a PIT tag. Creel clerks may also be asked to collect tissue samples for DNA analysis from unmarked rainbow trout; however no funding currently exists to complete a genetics inventory on wild rainbow trout. All creel information will be recorded in pencil on a standardized creel survey form. Creel information regarding PIT tagged fish will be reported biweekly to personnel responsible for maintaining the PIT tag database.

In addition to the above stated method, the project is currently looking into the potential use of Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICPMS) as a means of identifying if wild rainbow trout originated in the Sanpoil River.The Project is currently working with Pacific Northwest National Laboratories (PNNL) who has the expertise to use Laser Ablation. Specifics have not been developed and will not be ready for this proposal, however a brief overview is provided.

LA-ICPMS has been used to delineate stock and characterize movements, and natal origins of fish (Halden and Friedrich 2008; Mohan, J.A. 2009). The technique uses an extremely fine beam laser to ablate, or burn away, a very shallow layer of the otolith. The emissions from this are then analyzed for chemical composition (Thorrold 1998). Otolith microchemistry has been used to identify and delineate Atlantic cod stocks in Canadian waters (Campana et al 1994) and migratory patterns of whitefish (Halden and Friedrich 2008).

Before useable data can be obtained from the microchemical analysis of otoliths, the water chemistry must be understood. Once chemical signatures of regions of water are identified, the otoliths can be analyzed for comparison. When data for fish movements over time or natal origin data is desired then a targeted portion approach is used (Campana et al 1994, Halden and Friedrich 2008, Thorrold et al. 1998, Campana 1999; Mohan 2009).

The Project is currently working with Pacific Northwest Laboratories (PNNL) who has the expertise to use Laser Ablation. The plan for a wild redband trout study would consist of using otoliths from wild trout captured during creel surveys and testing them against water collected from the Sanpoil and from upstream of the Sanpoil. The otoliths could then be tested to determine if the water chemistry markers during the initial otolith growth matched the Sanpoil River. Currently the Project does not have a cost estimate for this method. During 2012, the Project plans to work with PNNL to determine if this method is appropriate and affordable to implement.

Monitor Escapement (2013-2017): The RM&E project will monitor lacustrine adfluvial escapement into the Sanpoil River from a weir trap installed near the mouth of the river. The project will operate the weir for two full years beginning in 2012 to identify peak escapement times (spring, summer and fall). After that (2014), the project will operate the weir only at the critical times. The mainstem PIT tag arrays will also be used to track movements of spawning fish within the system.  The fluvial populations will be monitored using the 8 arrays set in the primary tributary mouths.

Escapement data will enable the project to estimate interval (µ) and instantaneous (F) exploitation rates of Sanpoil River redband trout, using methods suggested by Lee and McLellan (2011). Exploitation will be defined as the rate of mortality from angler harvest. Interval exploitation (µ) is defined as the rate of mortality that occurs among a specified redband trout cohort over a given time interval (Miranda and Bettoli 2007). Juvenile traps will be used to estimate recruitment (R) and the recreational creel survey will be used to estimate harvest (H) of select populations of redband trout.  Therefore interval mortality for a specific cohort can be calculated by the following equation: 

 µ = H / R

The number of fish in a cohort does not decline linearly over time and consequently exploitation is unlikely to occur in a linear fashion; therefore, instantaneous exploitation (F) was defined by Miranda and Bettoli (2007) by the subsequent equation:

F = µZ/A

Where, Z is the total instantaneous mortality rate and A is the total interval mortality rate.  The A will be determined using escapement.  Instantaneous mortality rate (Z) at time t is determined by the equation (Miranda and Bettoli 2007):

Z_t = -Log_e (1 - (N₀ - N_t) / N₀)

Where, N₀ is the estimated number of fish recruiting to the fishery at time 0, referred to above as recruitment (R) and N_t is the estimated number of adult spawners at time t (escapement; S).  Z can then be calculated for any instant in time between time 0 and t by multiplying the fraction of the total time in question.  A can then be calculated by the ensuing equation (Miranda and Bettoli 2007):

A = 1 – e^-Z

The development of a standardized stock assessment project will enable biologists to estimate the current status of the redband stock relative to management targets. These estimates will then be used to suggest management activities to improve abundance of redband trout.

We will calculate the growth parameters of select stocks of redband trout using the von Bertalanffy growth function, represented by the equation

L_t = L_∞(1 - e^-k(t-t₀⁾)

where, L_t is the length of the fish at time t, L_∞ is the asymptotic length, k is the growth coefficient, and t₀ is the time coefficient when length of the fish would theoretically be equal to zero (Isely and Grabowski 2007). 

Age at maturity will be estimated from scales samples taken from fish collected in the weir, from or back calculations from age length frequency distributions.

Data obtained during this five year study will be combined and used by managers as a tool for conservation of the redband trout in the Sanpoil River basin.  The results will also be used in concert with the Habitat Improvement Project to monitor changes in the population status after habitat projects have been implemented.

Key Personnel 

CCT Project Lead: Ms. McLellan is a fisheries biologist who has studied fish populations in the Pacific Northwest for over twelve years. She is currently the sub-division lead, Fisheries Biologist 4 for the Colville Tribe. She oversees a mix of research projects that investigate the effects of the Columbia River hydropower system on resident salmonids.

CCT Lead Field Biologist: Mr. Simonsen is a fisheries biologist with a diverse range of field experience. As a Fisheries Biologist 1 with the Colville Confederated Tribes Resident Fish Division he currently oversees the daily operation of a weir trap and a screw trap. He also supervises and conducts creel surveys and the Fall Walleye Index Netting surveys on the lower third of Lake Roosevelt. Mr. Simonsen’s other recent fieldwork has included electrofishing, gill netting, SCUBA and snorkel visual census surveys. 

CCT Program Manager: Mr. Bret Nine is currently the CCT Resident Fish Program Manager. Prior to his current position, Mr. Nine was the Project Lead for the RM&E project. He has been working with redband trout in the Sanpoil River since 2006.

CCT Habitat Sub-division Lead: Mr. Jason McLellan currently leads the CCT Redband trout Habitat Improvement Project, the CCT White Sturgeon Recovery Project, and the CCT Burbot Stock Assesment Proejcts within Lake Roosevelt. He has conducted fisheries work on Lake Roosevoet for over 13 years. He was one of the primary authors for the development of the Redand Trout stock assesment protocols for Lake Roosevelt. Mr. McLellan has published papers on redband trout life histories, genetics, and stock status. The CCT Habitat Project works closely with the RM&E Project to develop appropriate stategies to monitor redband trout on the CCT Reservation.

Sub-contracts partners.

Pacific Northwest Laboratories: Dr. Rich Brown. Dr. Brown has extensive experience studying riverine salmonids and is a leading expert in the field of winter ecology.  He has years of experience refining methods to observe and study fish during the very challenging winter season.  Dr. Brown also has nearly two decades of experience using radiotelemetry.  Dr. Brown has extensive experience researching spawning behavior and migratory patterns of salmonids.