South Fork Tieton Bull Trout Population

Overview

The South Fork Tieton River population is one of three populations in the Rimrock Population Group. South Fork Tieton River is the largest tributary of Rimrock Reservoir, entering the reservoir from the south at its eastern end. Prior to impoundment the South Fork joined the North Fork in McAllister Meadows to form the mainstem Tieton River. The South Fork Tieton River originates in the Goat Rocks Wilderness Area, and most of the stream is contained within the Okanogan-Wenatchee National Forest. A waterfall 14.2 miles upstream of the reservoir is an impassable barrier for migratory fish. Numerous small tributary streams enter the South Fork Tieton River below this waterfall, including Bear, Short and Dirty, Grey, Spruce, and Corral creeks. Bear Creek, which enters the stream 1.6 miles below the barrier falls, is the largest of these. South Fork Tieton River is closed to fishing year-round to protect bull trout.

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Population Information

Population Distribution and Life History

The South Fork Tieton River supports a single local population of bull trout, which displays an adfluvial life history type. The known spawning area for this population is located entirely within the National Forest, extending from about RM 5.0 to the barrier waterfall in the main stem (Figure 1). Some spawning also occurs in Bear and Spruce creeks.

Figure 1. South Fork Tieton River sub watershed. spawning survey should be changed to "spawning survey index" and "known spawning" should include the area that gets surveyed frequently but isn't part of the index.  otherwise, how do we know that there was spawning there?

Juvenile bull trout primarily rear within the spawning area and have also been found in several of the creeks where spawning activity has not been documented. Rimrock Reservoir provides FMO habitat for subadult and adult fish. It appears that adult bull trout enter the South Fork Tieton River prior to spawning earlier than other populations in the Yakima Basin. A copy of a local angler’s fishing journal provided to Eric Anderson documented his catch from 1987-1994 and included bull trout caught in June. Snorkel surveys in 2000 to document spawning migration timing found adult bull trout moving into the river in late July (James 2002a).

The USFWS routinely encounters South Fork Tieton River origin fish at the base of Clear Creek Dam on the North Fork Tieton River during trap and haul work (Beebe et al. 2024). Since 2015, 48 of 268 (18.0 %) bull trout collected there were identified as South Fork Tieton River origin fish.

Natural Barriers limiting distribution

Figure 2. South Fork Falls is a 30 foot waterfall and a total passage barrier to adfluvial bull trout.

A 30 foot waterfall near RM 14 (46.521787, -121.262738), South Fork Falls, is an impassable barrier to migrating adfluvial bull trout (Figure 2). Barrier falls also occur on Bear Creek near RM 0.6 (46.53798, -121.26977).

Population Genetics

Results of genetic analyses show that this population is genetically distinct from all other populations in the Yakima Basin including the other adfluvial populations residing in Rimrock Reservoir (Indian Creek and North Fork Tieton River). All genetic samples were collected from post-spawn adults captured in 1996 and 2000 in a box trap deployed in the river. The population did cluster with the other Naches River fluvial populations, indicating some degree of gene flow (Reiss 2003; Small et al. 2009). This likely reflects a pre-dam exchange of genetic material and a more recent one-way genetic contribution from entrained fish.

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

Population Monitoring

WDFW began exploratory spawning surveys in the South Fork Tieton River in 1990 with a mainstem index area established and complete surveys started in 1994. Bear Creek was included in the survey after WDFW found numerous bull trout in the lower end of Bear Creek during electroshocking surveys that same year. Short and Dirty creeks were also electrofished in 1994, and juvenile bull trout were observed (Anderson 1994). In 1993 the Forest Service captured juvenile bull trout in minnow traps in several South Fork Tieton tributaries (Milk, Bear, Spruce and Corral creeks) (USFS 1993b). Sexauer (1994) estimated juvenile bull trout population density and derived length frequencies for both juveniles and adults in the South Fork Tieton River in 1992. The author also studied life history aspects of the species in the river and documented habitat use. James (2002a) trapped and tagged bull trout annually from 1995-2000 and conducted snorkel surveys in 1992, 1996, and 2000 while studying the population status and life history characteristics of the South Fork Tieton River bull trout population.

Entrainment of South Fork Tieton River bull trout through Tieton Dam has been documented. Thirty-seven bull trout were collected from the stilling basin during a fish salvage effort in 2005 and the subsequent analysis of genetic samples taken from these fish revealed eight bull trout assigned to the South Fork Tieton River population (Small et al. 2009). Two fish collected from the Tieton Dam stilling basin in July 2020 were both assigned to the South Fork Tieton River population but no other bull trout have been collected there despite repeated attempts (Haskell et al 2021). The deep turbulent stilling basin makes fish collection difficult.

In 2018, 2019, 2022 and 2023 WDFW performed night snorkel demographic surveys to get baseline information to inform using South Fork Tieton River as donor stock for bull trout reintroductions elsewhere in the Yakima Basin. Adult, juvenile, and young-of-year bull trout were observed. No brook trout were observed, and cutthroat were the most abundant species followed by bull trout and sculpin (Kline 2024, Personal Comm).

The USFWS has PIT antennas located in the South Fork Tieton River 0.25 miles upstream of its mouth at Rimrock Reservoir and another about 5 miles upstream of the mouth at the USFS Bakeoven Campground. The upstream site has operated since 2018, while the downstream site has operated since 2021. The sites generally operate from May - November when solar power is adequate. However, high flow events have destroyed the antennas causing some limited operations. Most of the fish interrogated are tagged through the USFWS trap and haul program at Clear Creek Dam.

Redd Surveys

Figure 3. South Fork Tieton River bull trout Annual Redd Counts 1990-2024

The spawning period for the South Fork Tieton River population occurs primarily during the month of September but can extend through mid-October. Complete bull trout redd surveys have been conducted in an index area on the South Fork Tieton River since 1994. This index area begins at river mile 8.4 in an area locally referred to as “Blue Slide” and extends 5.8 miles upstream to the barrier waterfall. Additional exploratory surveys were done for many non-consecutive years in the 3.5 miles directly below the mainstem index area, including some tributaries. In some years, as many as 30 additional redds were noted but not made part of the final count to keep year-to-year comparisons consistent. However, in 2018 an index from USFS Bakeoven Campground up to "Blue Slide" including Spruce Creek was solidified, and final counts from 2018 - present have included redds in this index. On average, this newer index is only surveyed once after peak spawning is thought to be over, as opposed to the three passes on other indexes.

Also included in the annual survey is 0.6 mile of Bear Creek from the mouth to an impassable barrier. This creek annually hosts large numbers of spawners despite its relatively small size and limited accessible length. In some recent years, there has been an impassable debris jam on Bear creek around RM 0.3, further reducing the extent of spawning habitat and likely diminishing redd counts in the creek.

Excluding 1995 (an incomplete survey year), an average of 163 redds have been counted annually (Figure 3). Some years, high flows and/or turbidity impact survey efforts.

Population Status and Trend

The USFWS (1998) did not consider the South Fork Tieton River population singularly. The agency 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). However, the effective population size is low (Small et. al 2009).

Despite some years with average and above average redd counts, spawning appears to be trending downward since the original Yakima Bull Trout Action plan was published in 2012. Redd counts from 2020-2022 were consecutively low and only 84 redds were counted in 2024, the lowest number since complete surveys began in 1996.

Although annual redd counts are relatively high when compared to other populations in the Yakima Basin, bull trout densities in South Fork Tieton are low. Densities are comparable to Box Canyon Creek but lower than Kachess River, Indian Creek, and Deep Creek (Kline, 2024 personal comm). It is important to note that only 3.5% of the total available habitat in South Fork Tieton was surveyed, whereas a higher percentage of available habitat was surveyed in the other streams mentioned above. More survey effort is needed to identify long-term trends for this population.

Habitat

Habitat Overview

South Fork Tieton River elevations range from 2,900 feet at the mouth to 3,850 feet at the base of the impassable waterfall located just over 14 miles upstream. As mentioned previously this entire reach is located in the Okanogan-Wenatchee National Forest. The primary land use activities in the watershed are recreation and livestock grazing.

Figure 4. Maximum daily water temperature at four locations in the South Fork Tieton river during the 2024 Summer season. Bear Creek is a tributary to the South Fork Tieton River.

Despite recreation, grazing, forest health, and passage issues described below in the Threats section, spawning and rearing habitat conditions in the six miles below the barrier falls are considered very good. Channel and riparian condition, LWD, pool frequency and quality, and water temperatures were reported as favorable for bull trout (Haring 2001). However, a full season of temperature monitoring in 2024, a drought year, indicated temperatures greater than 12 C from early July to mid-September (Figure 4).

The river appears to receive considerable sediment input from various sources, particularly in the area known as “Blue Slide” (RM 8.4), a natural landform.

Habitat Monitoring

Sexauer (1994) surveyed habitat use by juvenile and pre-spawning adult bull trout. Thomas (2001) assessed the potential impact of the waterfall at the confluence with Rimrock Reservoir on bull trout passage. Josberger et al. 2007 presented photographic evidence and density measurements indicating the Mead and Conrad glaciers in the river's headwaters continue to recede, which will change the timing and delivery of water to the South Fork Tieton River. Likewise, climber Kyle McCrohan photographed Conrad Glacier in September 2024 and published photographs of the shrinking glacier in a trip report.

The Forest Service and the Yakama Nation Timber Fish & Wildlife Program (TFW) worked cooperatively to maintain a long-term data set of sediment monitoring data in the South Fork Tieton River from 1999 to 2012 (Matthews 2011). This monitoring effort demonstrates an overall relatively high level of fine sediments in the substrate within the spawning reach (~12-14%), which would qualify as “functioning at risk” (USFWS 1999) and may indicate a need to address sediment sources in the drainage.

Field Habitat Surveys

The Forest Service completed habitat surveys on the South Fork Tieton River in 1991 (15.8 miles) and again in 2000 (6.0 miles) using the Hankin and Reeves protocol. Bear Creek and other associated tributaries were surveyed between 1991-1998. In all of these surveys, data were collected on pool/riffle frequency, riparian and channel condition, substrate, LWD, and temperature.

In 2024, Yakama Nation conducted a USFS Level 2 stream inventory (minus the fish and biological data) measuring physical characteristics. Metrics included channel unit designation, pool/riffle dimensions, side channels, LWD, etc. The survey extent was from Rimrock reservoir up to the base of South Fork Tieton Falls. The habitat was classified as "excellent" from Blue Slide to 1050 rd. while habitat near Lower Bakeoven campground area "did not look to be in the best condition" (Jonny Lambert, Yakama Nation, personal communication).

Stream Temperature Data

Water temperature was monitored in the South Fork Tieton River using thermographs deployed at three sites on the mainstem during the summer low flow period in most years from 1995-2007 (USFS 2011a). Other thermographs were deployed in associated tributaries, including Bear Creek during that same time period, primarily in 1995. There was a monitoring gap in temperature data from 2007 - 2019. The USFWS has continuously monitored water temperature at its lower South Fork Tieton River antenna site since 2023 and at its upper site since 2019. The USFS monitored temperatures in Grey and Spruce creeks, tributaries to South Fork Tieton River in 2023. Mid-Columbia Fisheries deployed temperature loggers in all the bull trout spawning indexes including Bear Creek in 2024.

Threats

Connectivity

Fish Passage Barriers

Threat Severity: Significant

The completion of Tieton Dam in 1925 disrupted the previous fluvial life history, in which fish from the South Fork Tieton River probably made extensive use of the Tieton River downstream of the dam as well as the Naches and Yakima rivers. The issues related to Tieton Dam are addressed in the Rimrock FMO section.

Access to the South Fork Tieton River was reduced when a bridge on Forest Service Road 1200 was constructed years ago. The natural channel of the river was relocated to flow under the bridge through a notch blasted out of bedrock. A waterfall begins to form at this location when the reservoir is drafted below 131,000 acre-feet. It is believed to become impassable for bull trout attempting to migrate upstream when the pool volume drops below 127,000 acre-feet (Thomas 2001). An informal agreement is in place with the USBR to maintain at least this minimum pool through August 10 of each year, the date Yakima basin biologists agree that the majority of bull trout have likely made their spawning migration into the South Fork Tieton River. Under current operations, heavy drafting of Rimrock Reservoir does not begin until early September and the reservoir has held more than 127,000 acre-feet on August 10 (average 177,155) for the 32 years since modern-day operations (i.e., flip-flop) were initiated in 1981. Previous to this at least part of the spawning migration may have been blocked from entering the South Fork Tieton. Yakima County is leading the effort to address the USFS Rd. 1200 bridge issues for protection of bull trout and for operational flexibility. Construction is planned for 2025 to return the South Fork Tieton River to its natural channel, which will do away with the seasonal waterfall, but also remove the August 10th restriction on pool level.

The effects on post-spawn bull trout that inevitably descend this waterfall on their outmigration back to Rimrock Reservoir are unknown. The effects on adult bull trout who start their upstream spawning migration later than August 10 is unknown but likely significant considering that many of the Bull Trout populations in the Yakima Basin have a bi-modal distribution spawning run with some migrating upstream in the early summer and some just before spawning.

Entrainment

Threat Severity: Unknown, but likely significant

No irrigation diversions or other sources of entrainment are located on the South Fork Tieton River. The issues related to entrainment at Tieton Dam are addressed in the Rimrock FMO section.

Dewatering due to flow management

Threat Severity: Unknown, but likely insignificant

It is unlikely that the South Fork Tieton River dewaters as it crosses the reservoir bed but there has not been any monitoring.

Land-use Issues

Forestry

Threat Severity: Unknown

Timber harvest has been heavy in the past but is now limited. However, the associated roads remain and road density in the watershed is relatively high. Except at crossings these roads are generally not close to the river, but a relatively high percentage of them (30%) are within high erosion hazard landforms (Haring 2001). Forest health in the South Fork Tieton watershed is a definite concern. A growing fear is that extensive beetle kill combined with high tree density could fuel a catastrophic wildfire.

The Forest Service and Yakama Nation are working together to plan and implement a large scale forest restoration project, encompassing the South Fork Tieton River watershed and adjacent areas. Project goals are to increase forest resilience to wildfire and disease. The watershed has experienced an extensive spruce budworm kill and the forest is at risk of a catastrophic wildfire with potentially dire consequences to this bull trout population.

Agriculture and Grazing

Threat Severity: Unknown, but likely significant

The USFS's cattle grazing allotment covers much of the watershed including the land on both sides of the river from the confluence with the reservoir upstream to Bear Creek. In addition, several acres upstream of the barrier falls in Conrad Meadows is actively managed as pasture. The area is currently vacant (spring 2025) but available to lease from the USFS. Livestock grazing (and direct access to the river) has impacted bank stability and riparian condition, most likely to a greater extent than recreation, as it has been more widespread. While significant measures have been recently implemented to address grazing impacts, they are an ongoing issue. The Tieton Allotment Management Plan (USFS 2006c - document requested from Naches RD) changed regulations to not allow grazing after August 15 in pastures adjacent to the South Fork Tieton River. As of 2010 the number of permitted livestock was reduced (prior to August 15) from 398 cow/calf pairs to 248 cow/calf pairs.

Recreation

Threat Severity: Unknown, but likely significant

Bank erosion and riparian damage has occurred in areas where two established campgrounds and scattered dispersed campsites are located. These same impacts have resulted from off-road vehicle use near the stream. The Forest Service did some work to address these issues in the early 2000s. A buck-and-rail fence was built at the dispersed campsite near the USFS rd.1050 bridge, reducing bank erosion and keeping vehicles out of the river in a known spawning location.

Monitoring equipment operated by the USFWS has been vandalized or stolen from Bakeoven campground and other locations often, which hinders research efforts.

The large group campsite on river-right near the mouth and the adjacent recreational access on river-left both host large numbers of people in the summer season. Impacts include illegal driving into the floodplain, trash, rock dams, and illegal angling. Trash and recreational dams are removed at many of the streamside campgrounds on the South Fork Tieton River by BTTF yearly.

Roads and Development

Threat Rating: Insignificant

Within the habitat accessible by bull trout there are four road crossings, all with bridges. The most problematic crossing is USFS Rd. 1200 at the mouth. The construction of the bridge re-routed the original channel and now there are fish passage issues when the reservoir pool is low. Construction to fix this issue was slated for 2025, but may be delayed due to funding availability. See Connectivity section above for details. See Land Use Issues section above for road information related to forestry.

Mining

Threat Severity: Insignificant

The South Fork Tieton River watershed does not have a documented history of mining activity.

Ecological Interactions

Brook Trout

Threat Severity: Unknown

Brook Trout were not observed in demographic surveys conducted in 2018, 2019, 2022 and 2023. The USFWS has collected one fish that was identified as a hybrid bull x brook trout with ancestry from the South Fork Tieton River, but it is possible the fish was a stray and the hybridization event occurred in a different tributary.

Other Invasive Species

Threat Severity: Insignificant

Other invasive species of fish have not been observed in demographic surveys.

Diminished Prey Base

Threat Severity: Unknown

South Fork Tieton 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 historically stocked with kokanee, which are now naturally reproducing and has proven productive enough to support relatively abundant populations of large adfluvial bull trout in the Lake's tributaries (see FMO section for more information).

The fish community observed during demographic surveys in 2018-2023 included healthy densities of cutthroat trout, sculpin, and whitefish which are all available as prey for bull trout in the river.

Disease

Threat Severity: Insignificant

Disease issues have not been noted for the South Fork Tieton River population.

Other

When Rimrock Reservoir is drawn down, the channel becomes exposed and offers little cover for bull trout to hide from predators.

Water Quantity and Quality

Flow issues/dewatering

Threat severity: Insignificant

Dewatering has not been noted in South Fork Tieton, although climate change may impact flows through the melting of glaciers and permanent snowfields in the headwaters.

Current and modeled future temperature conditions

Threat Severity: Unknown, but likely significant

NorWest model "current" (2011) temperatures are 12-14 degrees C near the mouth, 10-12 just above the mouth and up to Bear Creek, and 8-10 above Bear Creek and beyond the upstream fish passage barrier.  Temperatures are predicted to increase throughout S.F. Tieton by 2 degrees C by 2040 and by 2 to 4 degrees by 2080. A full season of temperature monitoring in 2024, a drought year, indicated temperatures greater than 12 C from early July to mid-September throughout the reach accessible to bull trout (Figure 4).

Other changes in hydrology

There is a naturally high sediment load in the lower portion of the river that can be attributed to "Blue Slide."

Fisheries Impacts

Angling Regulations/Fisheries Use/Poaching (Recreational)

Threat Severity: Unknown, but likely significant

Restrictions on angling have been in place since 1984 when a one-fish catch limit was imposed in the South Fork Tieton River. In 1992, fishing for bull trout became prohibited. In 1995 a total fishing closure was placed on the South Fork Tieton River and it remains closed to fishing today. In 2023 and 2024 emergency closures of shoreline fishing on Rimrock Reservoir near the mouth of South Fork Tieton, where bull trout tend to stage during or before the spawning season were put in place. Illegal angling has been documented and law enforcement regularly encounter anglers in or near the South Fork Tieton river. Bull Trout Task Force provides outreach to illegal anglers and remind them of the regulations when they are encountered. Most illegal anglers in the river are encountered near the mouth at campsites or recreation access areas and claim they did not know the river was closed to fishing, despite heavy signage noting the closure. Occasionally anglers at the mouth of the river pack up and leave as soon as they see the BTTF approaching. This indicates there is some level of intentional illegal angling.

The impact on the South Fork Tieton population from boat-based angling elsewhere in the reservoir is unknown. See Rimrock FMO section for more details.

Management/Monitoring (Research)

Threat Severity: Unknown, but likely insignificant

No ongoing fish sampling or tagging is occurring in South Fork Tieton at this time. The USFWS routinely encounters South Fork Tieton River origin fish during trap and haul work at the base of Clear Creek Dam on the North Fork Tieton River. Since 2015, 48 bull trout with genetic assignment to the South Fork Tieton River have been PIT tagged and released. See Population Monitoring section for more details.

Other Threats

Low Population Resiliency

Climate Change

Summary of Primary Limiting Factors

The highest severity threats to the South Fork Tieton River population of bull trout result from the presence of Tieton Dam. The dam precludes upstream gene flow from Naches River fluvial populations, entrains adult and subadult fish through the outlet works, and has eliminated anadromous fish access to the South Fork Tieton River. Other high and medium severity threats include illegal poaching in Rimrock Reservoir, potential introgression with brook trout, recreation activities (campsites adjacent to spawning areas), extensive forest health issues (forest management), and the passage barrier that prevents late-migrating bull trout from reaching spawning areas. Emerging threats include changes to timing and delivery of water as the climate warms and headwater glaciers recede. An overall increase in water temperature has also been observed. There is a grazing allotment within the spawning and rearing area but an agreement stipulates that cattle are to be excluded during the spawning period. However, cows were observed in Bear Creek in 2011 during spawning and in the mainstem during demographic surveys between 2018 and 2023, which may constitute a significant threat. Low abundance and low effective population size may be threat to the long term persistence of the population.

Recovery Strategy

Population-level Recovery Strategy

This population has been identified as a “Protection” population with a priority for continuation of population monitoring but with limited immediate restoration actions recommended. The highest priority actions involved improving passage conditions, both at a metapopulation scale (i.e., passage at Tieton Dam) and at a local population scale (i.e., relocate river to natural mouth). Passage is critical to the long-term genetic health of the population. Planning for two-way fish passage at Tieton Dam is underway with design completion expected by 2027. Designs are complete and funding is being sought for bridge reconstruction and relocation of the channel to its natural path to alleviate the seasonal waterfall formed under USFS road 1200 during draw-down (construction anticipated in 2025). Other recommended actions include outreach to document angling pressures and educate anglers, closing streamside campsites along the spawning and rearing reaches, implementing Forest Service Dry Forest Restoration Strategy, addressing problem roads, and ensuring that cattle are excluded during the spawning period. Prey base in Rimrock Reservoir should be reassessed. Kokanee were stocked historically, but now reproduce naturally in some tributaries to the reservoir. Numerous kokanee were entrained through Tieton dam during the 2024 drought year, but the impact to bull trout is unknown. Brook trout introgression should continue to be monitored as genetic samples are taken. No specific brook trout removal efforts are recommended at this time.

Monitoring Needs/Key Questions

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Evaluate feasibility and impacts of SFT as donor stock for potential reintroductions to other areas in the Yakima Basin.

Monitoring of river channel through reservoir bed during low pool to assess dewatering, passage issues, OHV use, and other challenges.

Actions

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

Completed Bull Trout Recovery Actions

• Tieton Allotment Management Plan (USFS 2006c) changed regulations to not allow grazing after August 15 in pastures adjacent to the South Fork Tieton River.
• As of 2010 the number of permitted livestock was reduced (prior to August 15) from 398 cow/calf pairs to 248 cow/calf pairs.
• Fencing (300 feet total) was constructed along South Fork Tieton River in 2002 and 2003 at a dispersed campsite and at Minnie Meadows Campground, protecting four acres of riparian habitat.
• Fencing (600 feet) was constructed in 2009 along lower Corral Creek protecting two acres of riparian habitat and eliminating motorized access.
• A Forest Service watershed restoration project in 2010 decommissioned 1.1 miles of system roads, decommissioned 0.3 miles of unauthorized jeep road, removed 4 impassible stream culverts on minor tributaries of South Fork Tieton River, and closed 2 jeep trail fords in bull trout spawning habitat (lower Spruce Creek and South Fork Tieton River at Grey Creek Campground)
• Fishing regulations have been implemented to protect bull trout in South Fork Tieton River including along the shoreline of the lake at the river's mouth during the spawning migration.

Recommended Actions

Relevant Multiple Population Actions

• Multiple Populations #1: Outreach on bull trout conservation issues (landowners, recreationists, anglers, school groups, and others).
• Multiple Populations #2: Continue annual spawning surveys in established index areas.
• Multiple Populations #3: Continue temperature monitoring.
• Multiple Populations #5: Carcass analog placement if pilot studies demonstrate success.
• Multiple Populations #8: Manage Rimrock 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)

South Fork Tieton Actions

• South Fork Tieton River #1: Minimize Dispersed Recreation Impacts on Bull Trout
• South Fork Tieton River #2: Address Problem Roads
• South Fork Tieton River #3: Implement Dry Forest Restoration Strategy
• South Fork Tieton River #4: Remove Passage Barrier at the Mouth
• South Fork Tieton River #5: Monitor Grazing Allotment Management Plan Implementation
• South Fork Tieton River #6: Assess Population for use as Donor Stock for Reintroduction (New in 2025)
• South Fork Tieton River #7: Address Threats of Illegal Angling in the South Fork Tieton River (New in 2025)

Actions in the Yakima Steelhead Recovery Plan that benefit this population

Areas upstream of Tieton Dam were not included in the Yakima 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: