Subbasin.  
Flathead Subbasin.  This project conducts mitigation actions in the Flathead River headwaters downstream to Flathead Lake, including lakes within the subbasin boundary.

Abstract

In 1991, the Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam (Mitigation Plan) was prepared by Montana Fish Wildlife & Parks (MFWP) and the Confederated Salish and Kootenai Tribes (CSKT) (MFWP and CSKT 1991).  The Mitigation Plan presented fisheries losses, mitigation options, and recommendations to protect, mitigate, and enhance resident fish and aquatic habitat affected by the construction and operation of Hungry Horse Dam.  The Northwest Power and Conservation Council (Council, formerly NWPPC) approved the loss statement: annual fisheries losses of 250,000 juvenile bull trout (Salvelinus confluentus) and 65,000 juvenile westslope cutthroat trout (Oncorhynchus clarki lewisi). The Mitigation Plan also identified 124 km of critical, low gradient spawning and rearing habitat that was inundated and lost when Hungry Horse Reservoir (HHR) filled.  To date, this program has improved approximately 25.8 km of stream habitat. The Council then directed MFWP and CSKT to immediately develop an Implementation Plan for federal fiscal year 1992.  The Council subsequently adopted the Hungry Horse Dam Fisheries Mitigation Implementation Plan (Implementation Plan) in 1993, which directs and prioritizes ongoing and future mitigation actions. This project is one of few federally funded, Columbia River mitigation projects carrying out a plan that has been specifically adopted by the Council.  On-the-ground mitigation activities began in 1992.  These elements were later adopted by the Council in the Flathead Subbasin Plan.

During this contract period (July 1, 2005 through June 30, 2006), Hungry Horse Mitigation (HHM) will complete work elements described in the SOW.  HHM will finalize planning for the 10-year South Fork Flathead Drainage Westslope Cutthroat Trout (WCT) Conservation Project designed to protect the strongest remaining core area for WCT in Montana.  Records of decision by BPA, MFWP and USFS will be completed this fall in preparation for project implementation next fall.  Mountain Lakes proposed for treatment will be monitored for trout genetics, macro-invertebrates and amphibians and additional assays will be performed.  During the interim, HHM will assist MFWP managment biologists to remove illegally introduced northern pike from the Martin Lakes near Olney, MT.  Once successfully treated, the two Martin Lakes will be  repopulated with a WCT trout fishery.  The Haskill Creek project was rescheduled for fall 2005 when plants will have better survival than during the heat of summer.  The Hallowatt Creek project will restore normative channel functions in 3 miles of prime bull trout spawning and rearing habitat using large woody debris and modest channel reconstruction activities.  Pit tag detection wiers installed during 2004 and 2005 will continue to monitor juvenile emigration and adult returns.  A larger weir is becoming operational on Trail Creek as part of the same investigation to determine the mechanisms responsible for expanding hybridization problems that threaten the remaining populations of genetically pure WCT populations downstream of Hungry Horse Dam.  These same weirs will be used to estimate recruitment of juvenile bull trout and WCT to the Flathead River.  Winter electrofishing and spawner surveys will determine growth and survival in the mainstem Flathead to assist with monitoring the effects of operations called for by the NPCC's mainstem amendments (pending full funding of the NPCC mainstem amendment monitoring project).  The recently developed RivBio benthic biomass model (developed by Natural Solutions) calibrated for two reaches in the Flathead and Kootenai Rivers, will be used to assess the relative influence of various dam operation scenarios.  Recent refinements of the reservoir models (HRMOD and LRMOD) will continue to assess biological responses attributable to various dam operation strategies in the reservoirs.  Pre-aquisition activities will occur on 10.7 acres adjacent to Sekokin Springs to determine the feasibility of purchasing the land to protect the headwaters of Spring #4 and provide room for future expansion of Sekokini Springs along the access road.  The Master Plan will be updated and a long-term RM&E plan will be developed for Sekokini Springs.  Our goal is to obtain NPCC approval through the 3-step APR process and begin renovating the site next year.  Our research on non-lethal sampling of fish scales to determine their stream of origin was published in TAFS in 2005 and research continues to assess more strontium isotopes to remove much of the remaining varience.  Combined, these projects were designed to protect native WCT and bull trout and their habitats and make progress toward mitigating the NPCC approved loss statement.

PROJECT BACKGROUND

In 1991, the Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam (Mitigation Plan) was prepared by Montana Fish Wildlife & Parks (MFWP) and the Confederated Salish and Kootenai Tribes (CSKT) (MFWP and CSKT 1991).  The Mitigation Plan presented fisheries losses, mitigation options, and recommendations to protect, mitigate, and enhance resident fish and aquatic habitat affected by the construction and operation of Hungry Horse Dam.  The Northwest Power and Conservation Council (Council, formerly NWPPC) approved the loss statement: annual fisheries losses of 250,000 juvenile bull trout (Salvelinus confluentus) and 65,000 juvenile westslope cutthroat trout (Oncorhynchus clarki lewisi). The Mitigation Plan also identified 124 km of critical, low gradient spawning and rearing habitat that was inundated and lost when Hungry Horse Reservoir (HHR) filled.  To date, this program has improved approximately 25.8 km of stream habitat. The Council then directed MFWP and CSKT to immediately develop an Implementation Plan for federal fiscal year 1992.  The Council subsequently adopted the Hungry Horse Dam Fisheries Mitigation Implementation Plan (Implementation Plan) in 1993, which directs and prioritizes ongoing and future mitigation actions. This project is one of few federally funded, Columbia River mitigation projects carrying out a plan that has been specifically adopted by the Council.  On-the-ground mitigation activities began in 1992.  These elements were later adopted by the Council in the Flathead Subbasin Plan.

PLANNING DOCUMENTS:

Bull Trout ESA Listing (63 FR 31647)
Westslope Cutthroat proposed Listing (63 FR 31691)
Bull trout recovery plans and actions (Montana Bull Trout Restoration Team 1997; Montana Bull Trout Scientific Group 1996a and 1996b; MFWP and CSKT 1991, 1993; Montana Westslope Cutthroat Trout Recovery Team)
NMFS hydrosystem operations for salmon recovery (56 FR 58619; 57 FR 14653; 2000 BiOp)
USFWS hydrosystem operations for bull trout recovery (USFWS 1999 and 2000 BiOp)

Project history  

See WORD document (tables would not fit in this form)

Scientific Framework (see WORD document for complete framework)  



Rationale for project selection and prioritization

The scientific framework addresses varying levels of scope, progressing from basin-wide issues toward site-specific details.  Each level is addressed by individual mitigation actions.  Our first priority is to prevent impacts that can reduce the overall health of the subbasin.  Basin-wide issues include federal and private dam operations and the prevention or containment of invasive aquatic nuisance species.   Onsite mitigation addresses habitat degradation, fish passage barriers, genetic introgression in pure native fish stocks and negative interactions between native and nonnative fish species. Offsite mitigation presents opportunities to create genetic reserves to conserve native species and to increase angling opportunities.

Basin-wide Priorities

Field research has shown that reservoir drawdown and refill failure reduces biological production in the Reservoir and create unnatural flow and temperature fluctuations in the Flathead River downstream.  Modifications to dam operation have a far-reaching influence on environmental conditions in the reservoirs and rivers throughout the Columbia River basin.  Montana has actively pursued a basin-wide operating strategy beneficial to imperiled fish stocks in the headwaters, as well as anadromous fish in the Columbia River downstream.  In the Hungry Horse Mitigation Plan, we estimated that modifying dam operation could mitigate roughly 50% of the Council-approved fisheries losses.  Much of the remaining losses can be mitigated using techniques that do not require changes in reservoir or river management.  Complete mitigation of the fisheries losses documented in the Mitigation Plan is not currently possible on-site, given the state of the science. Therefore, off-site mitigation will be necessary to achieve the best possible outcome. This mitigation program uses a mixture of fisheries techniques designed to produce the greatest benefit to the fishery resource.  Monitoring is used to assess the cost-effectiveness of various techniques and improve the program over time.
Field research has shown that reservoir drawdown and refill failure reduces biological production in the Reservoir and create unnatural flow and temperature fluctuations in the Flathead River downstream (Marotz et al. 1996).  Dam operations affected reservoir morphometry through alterations in surface area, water volume, shoreline length and water depth.  Combined, these changes adversely affected primary productivity, benthic invertebrates, and fish production in the reservoir.  Integrated Rule Curves (IRCs) were developed to balance the requirements of fish and wildlife with power production and flood control (Marotz et al. 1996). More recently, computer models developed by this project have been used to balance the requirements of resident fish in the headwaters (including ESA-listed resident fish species) with the needs of ESA-listed anadromous species in the lower Columbia River (USFWS 1999, 2000; Marotz et al. 1999).   The models have also been used to evaluate various flood control alternatives (SOR EIS 1995).

Aquatic nuisance species (ANS) pose an immense threat to aquatic ecosystems throughout the United States.  Preventing their establishment and spread in Montana is the best policy, and can save millions of dollars.  Even though BPA is not responsible for introducing ANS to the Columbia Watershed, once established, species such as Eurasian watermilfoil, zebra mussels, whirling disease, noxious weeds and exotic fish species, could be extremely difficult and expensive to control.   It is therefore in the interest of BPA and its rate payers to contribute to the solution.  For example, BPA could lose much revenue if zebra mussels  invaded penstocks, locks or fishways.  The first priority of Hungry Horse Mitigation is to prevent impacts that can reduce the overall health of the subbasin.  ANS projects are an integral component of our native fish restoration program in the Flathead River system, combating negative interactions between native and nonnative fish species and preventing the introduction of exotic aquatic organisms. Offsite mitigation presents opportunities to prevent the spread of invasive species that threaten the long-term persistence of native species assemblages in the upper Flathead River drainage.  Total eradication of ANS can be virtually impossible if not detected immediately, so prevention and early detection are critical to avoid disrupting of the ecological balance in the subbasin.  This project initiated a multi-agency cost-sharing program.  Cooperators use pamphlets, interpretive signs and public service announcements to alert the public to threats associated with ANS.  Pamphlets describe how to identify ANS, avoid their spread, and how to report their presence when discovered.  Radio traveler information systems are being installed to warn recreationists entering Montana to wash their vehicles and boats before traveling off road or launching on Montana's waterways.  

Subbasin Priorities

Priority areas for watershed restoration and preservation were developed based on habitat quality, fish community composition, and native fish abundance (See Flathead Subbasin Plan).   Focal species include genetically pure WCT and bull trout populations.  Fish habitat surveys are conducted to classify existing habitat conditions using a Rosgen habitat classification approach (Knotek et al. 1997).  Fish population surveys document the community structure of fish assemblages that share the basin.   Protection of undisturbed habitat that contains strong populations of native species was given the highest priority. Projects address riparian degradation, major sediment and nutrient sources, channel and bank instability, and impacts caused by non-native fish introductions.  Degraded watersheds with introduced species and limited or non-existent native fish populations were classified as lower priority for mitigation projects.
Maintaining the genetic integrity of native fish species is crucial to perpetuate native fish species and meets MFWP's responsibility to the Westslope Cutthroat Trout MOU and Conservation Agreement (1999).  Surveys have identified sources of genetic introgression between native westslope cutthroat and nonnative rainbow trout and Yellowstone cutthroat trout (Hitt 2003; Grisak 2003). Bull trout hybridize with brook trout where they coexist and the progeny are largely sterile. If no action is taken, genetic introgression will continue to erode the remaining stocks of native trout. Where possible, this project will remove nonnative species or attempt to prevent their spread to other waters.  In May 2005, MFWP, BPA and USFS will release a joint FEIS for our westslope cutthroat conservation project. The proposed action is to use icthyotoxins to remove nonnative and genetically introgressed fish that are threatening pure populations of native westslope cutthroat trout in the South Fork Flathead River drainage.  The development of this EIS has lead MFWP to conduct numerous field and lab evaluations. We investigated the performance of two icthyotoxins by assay on trout and non-target organisms like native amphibians (see Grisak et al. 2005a In prep). This will allow the highest level of precision when using fish toxins in a project as comprehensive as the South Fork Flathead Watershed Westslope Cutthroat Trout Conservation Project.  Monitoring has continued on  63 lake rotenone projects conducted from 1948 through 2000 to determine long term effects on non-target species and fisheries. HHM instituted the most comprehensive evaluation in area history on the status and distribution of native amphibians in 86 streams and 75 lakes in the South Fork Flathead River drainage (Grisak et al. 2005b). We conducted plankton analyses on 35 lakes to characterize seasonal abundance and species composition. In addition, HHM is testing the effectiveness of manually removing adult spawners from streams that contain hybrid populations by operating migrant traps during the spring spawning period.  
Streams that were damaged by fire during summer 2002 in the North Fork Flathead River will be repaired by the USFS.  An interagency cost-share has been arranged to simultaneously enhance or prevent fish passage depending on site-specific objectives.   In some locations, fish barriers will be maintained or installed to protect native stocks from competition and/or hybridization with exotic trout.. Barriers are usually constructed at existing road culverts.   Barriers will also be used to prevent spawning where concentrations of nonnative fish are discovered.  For example, radio-telemetry results demonstrated that Abbott Creek, a direct tributary to the main stem Flathead River near Hungry Horse, Montana, is a major source population of rainbow trout x westslope cutthroat trout  hybrids.  In 2002 we installed a fish barrier to preclude spawning and eliminate the threat of chronic genetic introgression. Another barrier installed on Gooderich Bayou of the Flathead River resulted in a 75% reduction in rainbow trout spawning in the first year alone. In other areas HHM improves fish passage to facilitate natural reproduction of native and endangered species.  For example, passage improvements at road culverts surrounding Hungry Horse Reservoir have increased the amount of spawning and rearing habitat remaining above full pool by 16 percent (Table 2).  Knotek et al. (1997) estimated that these fish passage projects will produce 5,221 juvenile WCT recruits to Hungry Horse Reservoir annually.   This estimate has not yet been verified post- construction.  Annual losses of naturally reproduced juvenile WCT caused by the construction and operation of Hungry Horse Reservoir was estimated at 65,000 (MFWP and CSKT 1991).  Secure populations will provide a source of genetic material to be used in future restoration activities at the Sekokini Springs facility.  

Information Dissemination and Stakeholder Involvement

Public and agency support for the mitigation program is crucial. Project staff informs citizens about the value of native fish species, teaches species identification and promotes the need for diverse habitat to support healthy fisheries.  We receive input from organized civic and sportsman groups, schools and cooperating agencies.  Fluvial dynamics are taught using visual aids such as the "stream table" to illustrate the affects of stream channelization, removal of riparian vegetation or stream restoration techniques.  When complete, the Sekokini Springs facility will play a vital role in public education and support for native fish restoration.  The proposed interpretive pathway at Sekokini Springs would inform the public and school groups on the importance of habitat, wetlands, native plants and animals, water conservation and impacts caused by species introductions.  Exhibits would highlight progress by HHM on westslope cutthroat trout conservation and timely issues.  Two fish viewing galleries would present an underwater view of Montana's state fish.  The site would also accommodate visiting scientists and volunteers. MFWP's "Hooked on Fishing" program introduces children and adults to sport fishing and fish conservation.  Project personnel present an aquatic education exhibit at the annual Forestry Expo, sponsored by conservation agencies and timber companies.