Indian Creek Bull Trout Population

Overview

The Indian Creek population is one of three populations in the Rimrock Population Group. Indian Creek originates in the William O. Douglas Wilderness Area and flows into the northwest end of Rimrock Reservoir. Approximately five miles of lower Indian Creek is accessible to bull trout; the bull trout distribution ends at a waterfall that is a total barrier to upstream passage. The creek and its watershed are entirely on US Forest Service lands; the uppermost mile of the accessible area is in the wilderness area. Several springs contribute constant flow to Indian Creek in the accessible reach; other than these, no perennial tributaries enter Indian Creek below the barrier waterfall. Based on redd counts, Indian Creek is one of the larger bull trout populations in the Yakima Basin, though abundance has fluctuated widely over time. Indian Creek is closed to fishing year-round to protect bull trout.

---

Population Information

Population Distribution and Life History

Indian Creek supports a single local population of bull trout, which expresses an adfluvial life history. The primary spawning area for this population extends from the U.S. Highway 12 bridge to the barrier waterfall 4.3 miles upstream although occasionally a few fish have been observed spawning a short distance below the bridge, usually within about a tenth of a mile (the distance from the bridge to the mouth of the creek is about a half mile). Between 2.0 and 2.5 miles above the bridge three springs enter the creek. The springs contribute significant flow and are utilized for spawning. Juvenile bull trout use the entire accessible length of Indian Creek for rearing. Rimrock Reservoir provides FMO habitat for subadult and adult fish (Figure 2).

Adult bull trout enter the creek in late August/early September just prior to commencement of spawning (James 2002a). The spawning period for the Indian Creek population occurs primarily during the month of September but can extend through mid-October.

Indian Creek fish have been shown to move throughout Rimrock Reservoir. The USFWS routinely encounters Indian Creek origin fish at the base of Clear Creek Dam on the North Fork Tieton River during trap and haul work. Since 2015, 73 of 268 (27.0%) of bull trout collected there were identified as Indian Creek origin fish. Two Indian Creek fish have been detected in the South Fork Tieton River (USFWS, personal comm).

Other tributaries to Rimrock Reservoir are small, steep and/or often blocked near their mouths. In 2024 during a culvert replacement on Andy Creek (a seasonal tributary to rimrock lake only 0.25 miles from Indian Creek) the Washington Department of Transportation found several sub-adult bull trout taking refuge in the pool below the culvert (Eitemiller 2024). More surveys are needed to collect genetic and distribution data, however, it is likely the bull trout originated from Indian Creek. Bull trout have not been documented in other tributaries.

Natural Barriers limiting distribution

Figure 1. Indian Creek Barrier Falls (river left).

Approximately four miles upstream of the confluence with Rimrock Reservoir (at high pool) there is a waterfall that is thought to be a total barrier to upstream passage (46.678993,-121.300758). At the barrier falls, the majority of the flow comes from a steep cascade on river-right (Figure 3) which originates from a spring while the remainder of the flow falls down a different cascade on river-left and originates from Apple and Pear Lakes (Figure 1).

Population Genetics

The Indian Creek population is genetically distinct from other populations in the Yakima Basin, including the other adfluvial populations residing in Rimrock Reservoir to which it is physically connected (South and North Fork Tieton rivers). To determine genetic variability within bull trout populations in the Yakima River basin, Reiss (2003) analyzed genetic samples collected from post-spawn adults in Indian Creek in 1996. Small et. al 2009 confirmed significant genetic distinction between Indian Creek bull trout and other Rimrock lake populations.

See more information under population genetics section of Rimrock Reservoir Populations Page.

Population Monitoring

In 1982 a snorkel survey was conducted on Indian Creek and found bull trout and cutthroat trout but no brook trout (Plum Creek Timber Company 1993 - ANYONE HAVE THIS REFERENCE?). Shortly thereafter in 1984, exploratory spawning surveys began with complete surveys conducted since 1988. The Indian Creek bull trout population has received considerable attention since. In 1994, when Plum Creek Timber Company returned and conducted night surveys, only bull trout and whitefish were observed (Plum Creek Timber Company 1995). In work for her CWU Master’s degree, Sexauer studied life history aspects of bull trout in several Okanogan-Wenatchee National Forest streams including Indian Creek, reporting on juvenile bull trout population densities (0.03 fish/100m) and habitat use (Sexauer 1994; James and Sexauer 1997). A CWU graduate student, Brenda James studied the feeding ecology of juvenile bull trout in the stream (James 1997). Paul James (2002a) studied the population status and life history characteristics of the Indian Creek population.

Polacek and James (2003) reported that bull trout were the predominant species in the creek but brook trout were also present at much lower densities (along with cutthroat trout, mountain whitefish, and sculpin). In 2022 and 2023 night demographic snorkel surveys were conducted by WDFW. The species observed previously were still present but with a notable increase in brook trout density. These surveys were intended to collect baseline bull trout demographic data to inform using Indian Creek as donor stock for future bull trout reintroductions elsewhere in the Yakima Basin.

The USFWS has two PIT antennas located in lower Indian Creek, 0.5 miles upstream of its mouth. The antennas have operated since 2019, generally from May - November as snow and available sunlight to power the antennas limit the operation period. Most of the fish interrogated are tagged through the USFWS trap and haul program at Clear Creek Dam. See Clear Creek dam sub-page for more info.

Figure 2. Indian Creek subwatershed - update maps?? Doesn't show spawning index reach

Redd Surveys

Complete redd surveys have been conducted on Indian Creek since 1988 from the U.S. Highway 12 bridge upstream to the barrier waterfall, a distance of 4.3 river miles. The index area includes two springs (Lower and Upper South Spring) each contributing single-channel flow, entering the creek on the right bank, and contributing 0.25 mile of spawning habitat. Another spring (North Spring) enters from the left bank. The North Spring has multiple channels totaling about 0.8 mile of spawning habitat. The surveyed index area covers nearly the entire length of the stream currently utilized for spawning.

Other Distribution Data (eDNA, etc.)

Figure 3. Indian Creek Bull Trout Redd Counts 1984-2024

Population Status and Trend

The number of redds observed in Indian Creek rose steadily over the first eight years of surveys to average over 200 between 1995 and 2000 (Figure 3). At the time the Indian Creek population was considered the largest in the Yakima Basin. In 2001, redd numbers declined to an average of 94 redds with two particularly depressed years. This may have been the result of the large winter flood in 1996 that scoured the primary spawning and rearing area for multiple age classes and affected adult recruitment five years later. Redd counts increased from 2007 to 2012, although not quite to the level observed during the earlier peak period. In 2013 a major landslide occurred in Indian Creek, which decreased spawning to a historic low due to stream sediment inundation in the North Spring and downstream. Sometime between 2019 and 2020 a debris jam formed near the mouth of the North Spring, precluding passage. Redds were not found in the North Spring until the problem corrected itself in the 2022-2023 runoff season. In the past decade, redd counts have been steadily increasing again to a high of 177 redds in 2023.

The USFWS (USFWS 1998) did not consider the Indian Creek population singularly, but considered the Rimrock “subpopulation” to be stable and increasing. WDFW similarly lumped the Rimrock adfluvial populations and rated the status of this stock as healthy (WDFW 2004). Given the spawning pattern evident over the last 25 years, it is difficult to determine a distinct trend for this population. It appears this population may be resilient enough to rebound from major disturbances. At this point the population can still be considered one of the most abundant in the basin, however, the effective population size may still be low (Small et. al 2009).

Habitat

Habitat Overview

Indian Creek is a relatively high elevation stream ranging from 2,900 feet at its mouth to about 3,700 feet at the upstream end of the spawning area. As mentioned previously, the upper mile (approximate) of the reach accessible to migratory bull trout is located in the William O. Douglas Wilderness Area. The remainder of the creek flows through the Okanogan-Wenatchee National Forest and, with the exception of the half-mile reach extending from the US Highway 12 Bridge to Rimrock Reservoir, is also relatively undisturbed. Habitat conditions in this reach were most recently reported in a 1999 stream survey report (USFS 1999). This report describes a stream with multiple channels occurring in 15% of the length surveyed (3.5 miles) having an active floodplain of variable width. The riparian corridor was healthy but often set back some distance from the active channel. Partly because of this, Indian Creek fell well below Forest Plan standards for LWD (USFS 1999). Since the presence of LWD is closely correlated with pool formation, the creek also fell well short of the standards for pool frequency and depth. In considering these observations it should be noted that well over a mile of the creek’s mainstem at the upstream end was not surveyed nor apparently were the three springs previously mentioned (see population distribution and life history). The quality of spawning and rearing habitat in the springs is considered excellent by local biologists, whereas about 2 miles of the mainstem is considered poor spawning habitat due to the over-widened channel, little vegetation nearby, and very low flow during migration and spawning season.

Since the 1999 stream survey report, there have been a number of landslides (the most substantial occurring in 2013) that have deposited material in the Indian Creek floodplain and contribute to over-widening of the channel. This is most noticeable in the valley bottom from the confluence of the North Spring to about 1 mile upstream of the wilderness boundary. The debris flows seem to be a natural occurrence not related to anthropogenic disturbance in the upper watershed. Another debris flow in 2019 filled the North Spring with fine sediment and created a network of braided channels.

Habitat quality in the reach below the bridge is not nearly as good as above it and diminishes appreciably closer to the mouth of the creek. See threats section for more information.

Climate Change impact on Habitat

THIS SECTION TO BE UPDATED AS ZAC COMPLETES TEMPERATURE MODELING

With new temperature data showing consistent cold water habitat in Indian Creek, it is important to note the importance of this stream as a refuge as other nearby stream temperatures rise due to climate change. (DUPLICATE FROM STREAM TEMPERATURE SECTION?)

Figure 4. A BTTF Technician sits below the barrier falls on river-right at Indian Creek

Habitat Monitoring

Field Habitat Surveys

Sexauer (1994) studied habitat use by juvenile and pre-spawning adult bull trout. James (1997) measured and summarized habitat parameters and water temperature in Indian Creek and the North Spring of Indian Creek. The Forest Service did a stream survey on Indian Creek in 1999, using Hankin and Reeves survey protocol (Hankin and Reeves 1988; USFS 1999). In these surveys, data were collected on pool/riffle frequency, riparian and channel condition, substrate, LWD, and temperature.

Polacek and James (2003) studied diel microhabitat use of age-0 bull trout in Indian Creek. Microhabitat variables included water depth and velocity, distance from the stream bottom, habitat and refuge use, substrate type, and substrate embeddedness.

During annual spawning surveys, the following observations have been made: low flows and split channels occasionally impede upstream migration, generally near Trail 1147 crossing at the end of the Indian Creek Road. In 2010, a high intensity rain event caused a delivery of high sediment from upland areas into the spawning and rearing area adjacent to the North Spring area of Indian Creek. Another large weather event in 2013 caused debris flows to contribute a substantial amount of fine sediment to the creek. Passage into the North Spring was inhibited by a natural woody debris jam starting in 2020 and became passable again in 2023. The upper extent of passage in the Lower South Spring is a large inactive beaver dam.

Stream Temperature Data

Indian Creek at the Highway 12 crossing was monitored for temperature via thermographs deployed during the summer low flow period in 10 out of 11 years from 1997-2007 (USFS 2011a). Other thermographs were deployed in and around the spring tributaries in 2000. Temperature data from 2007 to 2021 is a monitoring gap. The United States Fish and Wildlife Service started continuous temperature monitoring again in 2021 at the site of their PIT antennas, 0.5 miles upstream of the mouth. In fall of 2023, Mid-Columbia Fisheries started monitoring temperature in the North Spring, with several more thermographs deployed in the other springs and the mainstem in April of 2024. Monitoring is expected to continue as long as there is funding for equipment, time and maintenance of thermographs. ADD GRAPH?

The United States Forest Service NorWeST Stream Temperature Model predicts the coldest available habitat (0-8 degrees C) in Indian Creek to shrink by 2080, but remain less than 12 C throughout the next several decades. Recent temperature monitoring suggests that cold water (4-6 C) is consistently produced in the springs mentioned above, year-round. With new temperature data showing consistent cold water habitat in Indian Creek, it is important to note the importance of this stream as a refuge as other nearby stream temperatures rise due to climate change.

Restoration Actions

WDFW 2001 summarized temporary measures that were implemented to alleviate upstream adult bull trout passage impediments due to drought conditions, resulting low flows, low reservoir levels, and a wide, shallow steam channel. They also discuss the issue of recreational rock dams creating fish passage barriers under low flow conditions and what was done to alleviate that in the summer of 2001 (Croci 2001, WDFW 2001). As of 2017, WDFW fish passage biologists have monitored the alluvial fan of Indian Creek throughout the summer, opening passage or blocking of small braided channels to increase success of passage through one main channel (Rogala 2024)

In 2023 the BTTF rescued 56 bull trout young-of-year and 5 juvenile bull trout from dewatering side channels near the 1147 trail crossing. The fish were moved to perennial flow of the main channel.

Mid-Columbia Fisheries proposed a habitat restoration project for Indian Creek in the 2024 SRFB grant round, but it did not rank high enough to get funding due to the "natural" / "undisturbed" condition at Indian Creek.

Threats

Connectivity

Fish Passage Barriers (Check/update FDSI)

Threat Severity: significant

Tieton Dam blocks upstream passage into Rimrock Reservoir, leaving Indian Creek only accessible to adfluvial bull trout that already reside in Rimrock Reservoir. For more information see the Rimrock FMO page.

Occasional wood jams have precluded passage into the springs where spawning habitat is excellent.

Short reaches of the creek upstream of the three springs can experience dewatering in extremely dry years.

A final issue of moderate concern is passage conditions at the mouth of Indian Creek in late summer. Passage for pre-spawn bull trout may be impeded when flows and the reservoir volume are low such as occurred in 2001 when remedial measures had to be taken to reestablish connectivity (WDFW 2001). As of 2017, WDFW fish passage biologists have monitored the alluvial fan of Indian Creek throughout the summer, opening passage or blocking of small braided channels to increase success of passage through one main channel (Rogala 2024). As soon as Rimrock Reservoir is drawn down, passage at Indian Creek is affected. WDFW tracks and fixes issues as they arise.

USBR STUDY RESULTS WHEN THEY ARE PUBLISHED

Entrainment

Threat Severity: unknown, likely significant

No irrigation diversions or other sources of entrainment are located on Indian Creek. Indian Creek fish are subjected to downstream entrainment through Tieton Dam, after which they are unable to return upstream to Rimrock Reservoir and Indian Creek.

See Rimrock Reservoir Bull Trout Population Group for more information.

Dewatering due to flow management

Threat Severity: unknown

The Indian Creek alluvial fan is very dynamic, with the thalweg changing channels almost yearly. Often the water spreads out across several small channels in the inundation zone and can preclude fish passage when the pool level is low. When Rimrock Reservoir is drawn down far enough, Indian Creek flows into the North Fork Tieton River, which, depending on the water year, can flow for miles through the reservoir bed.

Land-use Issues

Forestry

Threat Severity: insignificant

The most recent timber harvest in the vicinity occurred over 20 years ago and no harvesting occurred near the riparian corridor. Thinning with the purpose of wildfire prevention was recently completed near the cabins and the lower part of the road.

Agriculture and Grazing

Threat Severity: insignificant

No agricultural activities occur in the watershed, and livestock grazing has not occurred in the area to any significant degree for over a century. REFERENCES FROM GENE SHULL

Recreation

Threat Severity: unknown, likely significant?

Above Highway 12 recreational impacts on Indian Creek is fairly limited due to limited access (the main use is by hikers and horse packers using the Indian Creek trail to access the William O. Douglas wilderness area). Occasionally, rock dams have been found near the bridge and the trail crossing.

Below Highway 12, the bottom 1/3 mile of Indian Creek experiences heavy recreational use, including motorized. The Indian Creek campground (a large, developed US Forest Service Campground), numerous cabins on US Forest Service land and the private Silver Beach Resort are located just to the east; there are also a moderate number of Forest Service lease cabins just to west of the creek. The riparian disturbance from the homes is minimal; some bank erosion occurs during snowmelt runoff in the spring. The campground does not significantly contribute to habitat degradation, but the activities of campers sometimes do. Wood, presumably for campfires, is often removed from the creek, but the larger issue is the construction of recreational dams that can impede upstream fish passage, and change the course of the flow. These obstructions are found and dismantled regularly by WDFW fish passage technicians (Rogala 2024) and the Mid-Columbia Fisheries Bull Trout Task Force (BTTF). Fishing impacts are addressed in a separate threat category below.

The Rimrock Grand Prix motorcycle race occurs at Silver Beach Resort each fall, with most of the racecourse located on the dry reservoir bed. Concerns have been raised about impacts on bull trout. WDFW and other partners have worked closely with the Dust Dodgers motorcycle club to minimize impacts on bull trout habitat during this event. The 2012 and 2017 BTAP primary concern was the motocross race, however, as of 2024 the race organizers and local biologists have taken yearly measures to prevent driving through the streams on that particular day and the threat of the race has been minimized (Shah 2024).

Aside from the sanctioned race, vehicles occasionally drive through the stream when the reservoir is low. A larger discussion on motorized access to the reservoir bed is needed (see Rimrock FMO page).

Roads and Development

Threat Severity: insignificant

Highway 12 crosses Indian Creek just above its mouth; the bridge does not appear to restrict floodplain function, as it is located at a natural bedrock constriction of the channel. The lower section of the creek is paralleled by Forest Service road 1308 for about three miles but its average distance from the stream is approximately 1,000 feet with a minimum distance of 300 feet. The upper end of this road has been closed since 2020, when a tributary crossing washed out. Overall road density in the watershed is very low.

The lower 1/3 of a mile of Indian Creek is surrounded by cabins, campgrounds and the Silver Beach Resort, as described above under Recreation.

Mining

Threat Severity: insignificant

No issues related to mining have been identified in the Indian Creek watershed. Only one exploratory mining site is known; the Indian Creek Cinnabar Property watershed was accessed by a jeep trail in the 1950s (visible as a trail headed up the draw to the east of Indian Creek just downstream of the falls on the USGS topographic map).

Other

No other land use issues have been identified.

Ecological Interactions

Brook Trout

Threat Severity: unknown, likely significant

Although no brook trout were observed in the initial 1982 snorkel survey of Indian Creek the species’ presence has since been confirmed by Polacek and James (2003) who reported that bull trout were the predominant species in the creek but brook trout were also present at much lower densities (along with cutthroat trout, mountain whitefish, and sculpin). Samples from 2001 and 2003 confirmed that hybridization between bull and brook trout occurred in Indian Creek (Small et al. 2009). Collating data from multiple genetic reports from 2001 to 2024, 56 individual bull trout have been identified with a substantial portion of Indian Creek ancestry. Only two of these 56 individuals have been confirmed as bull x brook hybrids. Only one trap and haul fish identified as a hybrid exhibited Indian Creek ancestry. In 2024 a male brook trout was observed on a redd with three adult bull trout in the South Spring of Indian Creek (Taylor 2024).

Other Invasive Species

Threat Severity: insignificant

Lake and brown trout are not present in Indian Creek or Rimrock Reservoir. Other invasive species issues have not been identified.

Diminished Prey Base

Threat Severity: unknown, likely significant

Indian Creek bull trout would once have had access to juvenile chinook, steelhead and coho salmon that spawned throughout the Tieton and Naches watersheds. This food source was eliminated when Tieton Dam was completed in 1925. However, the reservoir created by the dam, Rimrock Reservoir, was stocked with kokanee, which are now naturally reproducing, and has proven productive enough to support relatively large populations of large adfluvial bull trout in the lake and it's tributaries (see FMO section for more information).

Disease

Threat Severity: insignificant

Disease issues have not been noted for the Indian Creek population.

Water Quantity and Quality

Flow issues/dewatering

Threat Severity: unknown, likely significant

Indian Creek upstream of the Rimrock Reservoir reservoir bed has an essentially natural hydrograph. Dewatering within the upper spawning reaches has been occasionally observed. In 2012, this was not believed to be a significant threat, but since ~2020, dewatering has been observed in most years in late summer/early fall upstream of the North Spring confluence to the 1147 trail crossing. Low flows and highly braided channels likely preclude fish passage for part of the season in this reach. Additionally, stranding, desiccation, and predation of juvenile bull trout occurs in this braided section as observed by BTTF in 2023.

Fish passage issues where Indian Creek crosses the bed of Rimrock Reservoir at low pool levels are addressed above under connectivity.

Current and modeled future temperature conditions

Threat Severity: unknown, likely insignificant

COULD USE QUICK ANALYSIS OF TRENDS BY USFWS WHO HAVE MONITORED FOR SEVERAL YEARS

Indian Creek is modelled by NorWest to maintain relatively cold temperatures into the future. Water between 4-6 C is produced in the three springs year-round.

Other changes in hydrology

Somewhat regular debris flows and landslides have occurred in the Indian Creek watershed, with a recent notable event happening in 2013 (see Habitat Overview section). Massive debris flows likely decrease spawning for the years following the event due to fine sediments. Debris flows also contribute substantial amounts of material to the valley bottom which may contribute to over-widening, decreased riparian vegetation, and stranding in low flow side channels. However, alluvial fans may also increase rearing habitat and provide velocity refuge during high flows. Fluctuation of the reservoir could exacerbate passage and stranding issues near the Indian Creek mouth after a large debris flow.

Fisheries Impacts

Angling Regulations/Fisheries Use/Poaching (Recreational)

Threat Severity: unknown, likely significant

The 6 miles of Indian Creek below the barrier falls has been closed to fishing since the 1990s. In 2023 the sections of Indian Creek and North Fork Tieton River flowing across the reservoir bed were closed to fishing when the pool was drawn down. Fishing is allowed in Rimrock Reservoir (see Rimrock FMO section) and poaching of bull trout has been reported in the past near the mouth of Indian Creek.

Management/Monitoring (Research)

Threat Severity: unknown, likely insignificant

The USFWS has collected and tagged 75 Indian Creek fish since 2016 during USFWS trap and haul efforts at Clear Creek Dam. In 2023 the BTTF rescued 56 bull trout young-of-year and 5 juvenile bull trout from dewatering side channels near the 1147 trail crossing. The fish were moved to perennial flow of the main channel. See Population Monitoring section for details.

Other Threats

Low Population Resiliency

Climate Change

Summary of Primary Limiting Factors and Threats

Several of the highest severity threats to this population result from the presence of Tieton Dam (passage barriers, entrainment and prey base). The dam precludes gene flow with downstream Naches River fluvial populations, entrains adult and subadult fish, and has eliminated anadromous salmon as a food and nutrient source in Indian Creek. Other threats likely to have a significant impact on the population include recreational rock dam construction below the highway 12 bridge and poaching of bull trout in the reservoir and near the mouth of Indian Creek (although unquantified). Motorized travel through Indian Creek and the North Fork Tieton River continues to occur when reservoir levels are low, emphasizing a need for blanket restrictions. Introgression with brook trout is likely a significant threat, especially with recent observations of male brook trout attempting to "sneak" into redds with bull trout present in the springs. Finally, low abundance and low effective population size remain a potential threat to this population given the periods of low abundance that have been observed.

Recovery Strategy

Population-level Recovery Strategy

This population has been identified as a “Protection” population. The highest priority action is implementation of fish passage at Tieton Dam, which is critical to the long-term genetic health of the population. Planning for two-way fish passage at Tieton Dam is underway with completion of designs expected by 2027. Cold water spring preservation and mainstem habitat restoration are recommended actions, which would address issues of limited spawning and rearing habitat and reduce potential impacts from large debris flows. Spawning and rearing habitat is excellent in the springs where there is very cold water, but the extent of spring habitat is limited and can be impacted by disturbance events. Despite its challenges, brook trout suppression or eradication is recommended to prevent further introgression with the Indian Creek bull trout population. Population monitoring, outreach to educate anglers and recreationists and annual removal of recreation dams should be continued. Monitoring of passage conditions at the mouth, addressing motorized recreation across the stream when reservoir levels are low, and finally quantifying the impact of illegal harvest are also needed. Prey base should be reassessed to determine if kokanee are abundant enough to provide a regular food source for Indian Creek bull trout. Fish passage planning at Clear Creek Dam is complete and construction of a new fish ladder and cool water intake pipe will occur from 2025 - 2027, which will allow mixing of Rimrock Reservoir populations.

Monitoring Needs/Key Questions

---

Reassess habitat quality including dewatering extent and timing.

Study to understand the extent of brook trout introgression

Conduct updated prey base assessment in Rimrock Reservoir

Plan projects/research that address "Threat severity: unknown, likely significant"

Determine if stream productivity is limiting juvenile survival (before considering carcass analog placement)

Actions

Future link/ iframe to PowerApp will go in this section.

Completed Bull Trout Recovery Actions

• Fishing regulations implemented to protect bull trout in Indian Creek (see Appendix F).

Recommended Actions

Relevant Multiple Population Actions

• Multiple Populations #1: Outreach on bull trout conservation issues (cabin owners, recreationists, anglers, school groups, and others).

• Multiple Populations #1: Identify recreational dams annually and remove as necessary.
• Multiple Populations #3: Continue temperature monitoring
• Multiple Populations #5: Carcass analog placement if pilot studies demonstrate success.
• Multiple Populations #7: Continue to screen all genetic samples for evidence of genetic introgression with brook trout.
• Multiple Populations #8: Manage Tieton Dam operations to reduce entrainment.
• Multiple Populations #9: Periodic entrainment studies at storage dams
• Multiple Populations: Creel survey of Rimrock Reservoir anglers to quantify impact of angling. (New action 2025)
• Multiple Populations: Conduct updated prey base assessment in Rimrock Reservoir. (New action 2025)
• Rimrock FMO Action #3: Conduct studies to determine low pool impacts on bull trout (work toward an evidence based threshold / recommendation). (New action 2025)

Indian Creek Actions

• Indian Action #1: Ensure no impacts from motorized use of the reservoir bed
• Indian Action #2: Test for genetic trends over time
• Indian Action #3: Monitor and address passage in Indian Creek
• Indian Action #4: Stream and Habitat Restoration
• Indian Action #5: Assess options for channel stability in the upper reach. (New action 2025)
• Indian Action #6: Move toward brook trout eradication in Indian Creek headwaters. (New action 2025)

Actions in the Yakima Steelhead Recovery Plan that benefit this population

Areas upstream of Tieton Dam was not addressed in the Steelhead Recovery Plan.

Update Notes

2012 BTAP text copied into Yakipedia and edited to match new format in October 2024 by Aimee Taylor. ADD LINK TO 2012 BTAP pdf placemark

Additional edits proposed by Alex Conley, Aimee Taylor and Rimrock populations small group. Reviewed, and updated and approved by BTWG in February 2025.

Specific detail on out of cycle updates: