USGS ScienceSearch

Geology topics

Patrick J. Connolly

Publications and source records attributed to Patrick J. Connolly.

At least 37 records · Page 2Linked to original sources

The floodplain food web mosaic: a study of its importance to salmon and steelhead with implications for their recovery

Although numerous studies have attempted to place species of interest within the context of food webs, such efforts have generally occurred at small scales or disregard potentially important spatial heterogeneity. If food web approaches are to be employed to manage species, studies are needed that evaluate the multiple habitats and associated webs of interactions in which these species participate. Here, we quantify the food webs that sustain rearing salmon and steelhead within a floodplain landscape of the Methow River, Washington, USA, a location where restoration has been proposed to restore side channels in an attempt to recover anadromous fishes. We combined year-long measures of production, food demand, and diet composition for the fish assemblage with estimates of invertebrate prey productivity to quantify food webs within the main channel and five different, intact, side channels; ranging from channels that remained connected to the main channel at low flow to those reduced to floodplain ponds. Although we found that habitats within the floodplain had similar invertebrate prey production, these habitats hosted different local food webs. In the main channel, 95% of total prey consumption flowed to fishes that are not the target of proposed restoration. These fishes consumed 64% and 47% of the prey resources that were found to be important to fueling chinook and steelhead production in the main channel, respectively. Conversely, in side channels, a greater proportion of prey was consumed by anadromous salmonids. As a result, carrying capacity estimates based on food were 251% higher, on average, for anadromous salmonids in side channels than the main channel. However, salmon and steelhead production was generally well below estimated capacity in both the main and side channels, suggesting these habitats are under-seeded with respect to food, and that much larger populations could be supported. Overall, this study demonstrates that floodplain heterogeneity is associated with the occurrence of a mosaic of food webs, all of which were utilized by anadromous salmonids, and all of which may be important to their recovery and persistence. In the long term, these and other fishes would likely benefit from restoring the processes that maintain floodplain complexity.

Washington

Theoretical life history responses of juvenile Oncorhynchus mykiss to changes in food availability using a dynamic state-dependent approach

Marine subsidies can play an important role in the growth, survival, and migratory behavior of rearing juvenile salmonids. Availability of high-energy, marine-derived food sources during critical decision windows may influence the timing of emigration or the decision to forego emigration completely and remain in the freshwater environment. Increasing growth and growth rate during these decision windows may result in an altered juvenile population structure, which will ultimately affect the adult population age-structure. We used a state dependent model to understand how the juvenile Oncorhynchus mykiss population structure may respond to increased availability of salmon eggs in their diet during critical decision windows. Our models predicted an increase in smolt production until coho salmon eggs comprised more than 50 percent of juvenile O. mykiss diet at the peak of the spawning run. At higher-than intermediate levels of egg consumption, smolt production decreased owing to increasing numbers of fish adopting a resident life-history strategy. Additionally, greater growth rates decreased the number of age-3 smolts and increased the number of age-2 smolts. Increased growth rates with higher egg consumption also decreased the age at which fish adopted the resident pathway. Our models suggest that the introduction of a high-energy food source during critical periods of the year could be sufficient to increase smolt production.

Open-File Report

Using broad landscape level features to predict redd densities of steelhead trout ( Oncorhynchus mykiss ) and Chinook Salmon ( Oncorhynchus tshawytscha ) in the Methow River watershed, Washington

We used broad-scale landscape feature variables to model redd densities of spring Chinook salmon ( Oncorhynchus tshawytscha ) and steelhead trout ( Oncorhynchus mykiss ) in the Methow River watershed. Redd densities were estimated from redd counts conducted from 2005 to 2007 and 2009 for steelhead trout and 2005 to 2009 for spring Chinook salmon. These densities were modeled using generalized linear mixed models. Variables examined included primary and secondary geology type, habitat type, flow type, sinuosity, and slope of stream channel. In addition, we included spring effect and hatchery effect variables to account for high densities of redds near known springs and hatchery outflows. Variables were associated with National Hydrography Database reach designations for modeling redd densities within each reach. Reaches were assigned a dominant habitat type, geology, mean slope, and sinuosity. The best fit model for spring Chinook salmon included sinuosity, critical slope, habitat type, flow type, and hatchery effect. Flow type, slope, and habitat type variables accounted for most of the variation in the data. The best fit model for steelhead trout included year, habitat type, flow type, hatchery effect, and spring effect. The spring effect, flow type, and hatchery effect variables explained most of the variation in the data. Our models illustrate how broad-scale landscape features may be used to predict spawning habitat over large areas where fine-scale data may be lacking.

Washington

Distribution and movement of Big Spring spinedace ( Lepidomeda mollispinis pratensis ) in Condor Canyon, Meadow Valley Wash, Nevada

Big Spring spinedace (Lepidomeda mollispinis pratensis) is a cyprinid whose entire population occurs within a section of Meadow Valley Wash, Nevada. Other spinedace species have suffered population and range declines (one species is extinct). Managers, concerned about the vulnerability of Big Spring spinedace, have considered habitat restoration actions or translocation, but they have lacked data on distribution or habitat use. Our study occurred in an 8.2-km section of Meadow Valley Wash, including about 7.2 km in Condor Canyon and 0.8 km upstream of the canyon. Big Spring spinedace were present upstream of the currently listed critical habitat, including in the tributary Kill Wash. We found no Big Spring spinedace in the lower 3.3 km of Condor Canyon. We tagged Big Spring spinedace ≥70 mm fork length (range 70–103 mm) with passive integrated transponder tags during October 2008 (n = 100) and March 2009 (n = 103) to document movement. At least 47 of these individuals moved from their release location (up to 2 km). Thirty-nine individuals moved to Kill Wash or the confluence area with Meadow Valley Wash. Ninety-three percent of movement occurred in spring 2009. Fish moved both upstream and downstream. We found no movement downstream over a small waterfall at river km 7.9 and recorded only one fish that moved downstream over Delmue Falls (a 12-m drop) at river km 6.1. At the time of tagging, there was no significant difference in fork length or condition between Big Spring Spinedace that were later detected moving and those not detected moving. We found no significant difference in fork length or condition at time of tagging of Big Spring spinedace ≥70 mm fork length that were detected moving and those not detected moving. Kill Wash and its confluence area appeared important to Big Spring spinedace; connectivity with these areas may be key to species persistence. These areas may provide a habitat template for restoration or translocation. The lower 3.3 km of Meadow Valley Wash in Condor Canyon may be a good candidate section for habitat restoration actions.

Nevada

Wind River watershed restoration. Annual report. November 2011 through October 2012

Introduction This report summarizes work by U.S. Geological Survey’s Columbia River Research Laboratory (USGS-CRRL) in the Wind River subbasin, from November 2011 through October 2012. Funding was provided by Bonneville Power Administration (BPA) under contract 55275. The primary focus of USGS activities during this time was tagging of parr steelhead Oncorhynchus mykiss with Passive Integrated Transponder (PIT) tags, and establishing a network of instream PIT tag interrogation systems (PTIS). The PIT-tagged parr steelhead will provide movement and life history data through recapture events and detections at instream PTIS systems, will contribute to estimates of adult steelhead returning to the Wind River, and aid in the evaluation of the removal of Hemlock Dam on Trout Creek steelhead populations. The Wind River Watershed project (BPA Project Number 1998-019-00) is a collaborative effort to restore wild steelhead in the Wind River, WA. The four partner agencies are the U.S. Forest Service (USFS), Washington Department of Fish and Wildlife (WDFW), USGS-CRRL, and Underwood Conservation District (UCD). This partnership was established in the early 1990s with support from BPA, and has continued to conduct extensive habitat, research, monitoring, and coordination activities across the subbasin. The project works at multiple levels to identify and characterize key limiting habitat factors in the Wind River; restore degraded habitats and watershed processes; document fish populations, life histories, and interactions; investigate efficacy of restoration actions; and to share information across agency and non-agency boundaries. Long-term research in the Wind River has focused on assessments of steelhead/rainbow trout populations, relationships with introduced populations of spring Chinook salmon O. tshawytscha and brook trout Salvelinus fontinalis , and effects of habitat variables and habitat restoration on fish productivity. During the period covered by this report, we PIT tagged steelhead parr in headwater sections of the subbasin (Figure 1), maintained a PTIS in Trout Creek, installed a PTIS in the Wind River, and installed smaller scale PTISs in Trapper Creek, Paradise Creek, and the Wind River upstream of Paradise Creek (Figure 2). Additionally we maintained thermologgers to collect water temperature data near the PIT tagging sites. A statement of work (SOW) was submitted to BPA in October 2011 that outlined work to be performed by USGS-CRRL. The SOW was organized by Work Element (WE), with each describing a research task. This report summarizes the progress completed under each WE.

Washington

Potential effects of changes in temperature and food resources on life history trajectories of juvenile Oncorhynchus mykiss

Increasing temperatures and changes in food resources owing to climate change may alter the growth and migratory behavior of organisms. This is particularly important for salmonid species like Oncorhynchus mykiss , where some individuals remain in freshwater to mature (nonanadromous Rainbow Trout) and others migrate to sea (anadromous Steelhead). Whether one strategy is adopted over the other may depend on the individual's growth and size. In this study, we explored (1) how water temperature in Beaver Creek, a tributary to the Methow River, Washington, may increase under four climate scenarios, (2) how these thermal changes may alter the life history trajectory followed by O. mykiss (i.e., when and if to smolt), and (3) how changes in food quality or quantity might interact with increasing temperatures. We combined bioenergetic and state-dependent life history models parameterized for O. mykiss in Beaver Creek to mimic baseline life history trajectories. Based on our simulations, when mean water temperature was increased by 0.6°C there was a reduction in life history diversity and a 57% increase in the number of individuals becoming smolts. When mean temperature was increased by 2.7°C, it resulted in 87% fewer smolts than in the baseline and fewer life history trajectories expressed. A reduction in food resources led to slower growth, more life history trajectories, and a greater proportion of smolts. In contrast, when food resources were increased, fish grew faster, which reduced the proportion of smolts and life history diversity. Our modeling suggests that warmer water temperatures associated with climate change could decrease the life history diversity of O. mykiss in the central portion of their range and thereby reduce resiliency to other disturbances. In addition, changes in food resources could mediate or exacerbate the effect of water temperature on the life history trajectories of O. mykiss .

Transactions of the American Fisheries Society

Monitoring of stream restoration habitat on the main stem of the Methow River, Washington, during the pre-treatment phase (October 2008-May 2012) with a progress report for activities from March 2011 to November 2011

Introduction The U.S. Geological Survey (USGS) received a request from the Bureau of Reclamation (Reclamation) to provide monitoring and an evaluation of the effectiveness of habitat actions that Reclamation plans to implement in the Upper Columbia River basin, which includes the Methow River. This monitoring and evaluation program is to partially fulfill Reclamations part of the 2008 Biological Opinion for the Federal Columbia River Power System that includes a Reasonable and Prudent Alternative (RPA) to protect listed salmon and steelhead across their life cycle. The target species in the Methow River for this monitoring and restoration effort include Upper Columbia River (UCR) spring Chinook salmon ( Oncorhynchus tshawytscha ), UCR steelhead ( O. mykiss ), and bull trout ( Salvelinus confluentus ), which are listed as threatened or endangered under the Endangered Species Act. This report covers UCR activities performed by USGS personnel from March 2011 to November 2011. It involves collecting and analyzing data collected during pre-implementation (2008–2012) there will be a follow-up after actions are completed (2012–2014). The goal of Reclamation is to maximize the potential of habitat and improve proposed limiting factors affecting the middle Methow River subwatershed (Reclamation, 2010). The Middle Methow (M2) reach (river kilometer mile [rkm] 843.065 to 843.080) of the Methow River was selected as the treatment reach for this study based on possible stream restoration plans by Reclamation (fig. 1). The upper Methow River (rkm 843.094 and 843.080), Chewuch River, and the Methow River downstream of the Twisp River (rkm 843.065) are being sampled as reference and control reaches in this study (fig. 2). This report covers the third year in the pre-evaluation of the M2 reach and its side channels. Restoration of the M2 reach is scheduled for 2012, which is planned to be followed by a multi-year intensive post-evaluation period. The intent of the summary of information provided in this report is to fulfill the objectives and tasks submitted in a statement of work to Reclamation in November 2010 (Connolly and Martens, 2011). The study design provides data by which to assess potential fish response to a Reclamation habitat restoration effort focused to improve juvenile salmonid rearing habitat in the M2, which runs between the towns of Winthrop and Twisp, Washington (fig. 1). The pre-treatment phase of the study is designed so that specific questions about the response of target fish species (spring Chinook salmon, steelhead, and bull trout) to the restoration actions can be addressed. Effectiveness is being determined by measuring fish productivity and habitat connectivity of the restoration reach and adjoining reaches, and their tributaries. The study includes sampling efforts directed to understand the relationships between stream habitat and the abundance of various fish species and to assess the response of the fish community. To complement these measurements, we will use models to predict response to treatment, and we will update the model with empirically derived data as these data become available. This modeling effort is expected to inform us of data gaps, sensitivity of key variables, and ability to detect response based on variability of the data. The approach and actions taken or planned by Reclamation to modify off-channel habitat are largely untested as to their effectiveness to improve target fish species’ productivity and survival needs. Those documented strategies that identify both physical parameters and biological relationships and benefits have been identified (Reclamation, 2008). To assess biological performance, we plan to compare age structure, growth, and age at smolting between those fish that stay in natal areas versus those fish that move. To assess retention in, and movement from or into, the restoration reach, we have used a combination of within-reach and out-of-reach sampling. We are using passive integrated transponder (PIT) tags, a network of instream PIT tag interrogation systems, and smolt traps to assess differences in biological performance and the magnitude of retention in, and movement from and into, the restoration reach.

Washington

Fish population and habitat analysis in Buck Creek, Washington, prior to recolonization by anadromous salmonids after the removal of Condit Dam

We assessed the physical and biotic conditions in the part of Buck Creek, Washington, potentially accessible to anadromous fishes. This creek is a major tributary to the White Salmon River upstream of Condit Dam, which was breached in October 2011. Habitat and fish populations were characterized in four stream reaches. Reach breaks were based on stream gradient, water withdrawals, and fish barriers. Buck Creek generally was confined, with a single straight channel and low sinuosity. Boulders and cobble were the dominant stream substrate, with limited gravel available for spawning. Large-cobble riffles were 83 percent of the available fish habitat. Pools, comprising 15 percent of the surface area, mostly were formed by bedrock with little instream cover and low complexity. Instream wood averaged 6—10 pieces per 100 meters, 80 percent of which was less than 50 centimeters in diameter. Water temperature in Buck Creek rarely exceeded 16 degrees Celsius and did so for only 1 day at river kilometer (rkm) 3 and 11 days at rkm 0.2 in late July and early August 2009. The maximum temperature recorded was 17.2 degrees Celsius at rkm 0.2 on August 2, 2009. Minimum summer discharge in Buck Creek was 3.3 cubic feet per second downstream of an irrigation diversion (rkm 3.1) and 7.7 cubic feet per second at its confluence with the White Salmon River. Rainbow trout ( Oncorhynchus mykiss ) was the dominant fish species in all reaches. The abundance of age-1 or older rainbow trout was similar between reaches. However, in 2009 and 2010, the greatest abundance of age-0 rainbow trout (8 fish per meter) was in the most downstream reach. These analyses in Buck Creek are important for understanding the factors that may limit fish abundance and productivity, and they will help identify and prioritize potential restoration actions. The data collected constitute baseline information of pre-dam removal conditions that will allow assessment of changes in fish populations now that Condit Dam has been removed and anadromous fish have an opportunity to recolonize Buck Creek.

Washington

Hood River PIT-tag interrogation system efficiency study. Annual report of U.S. Geological Survey activities: November 2010-October 2011

Introduction During summer 2010, an agreement was made between the US Geological SurveyColumbia River Research Laboratory (USGS-CRRL) and the Confederated Tribes of the Warm Springs (CTWS) to operate an experimental Passive Integrated Transponder (PIT)-tag interrogation system (PTIS) near the mouth of the Hood River for a year and provide fishdetection efficiency estimates (Bonneville Power Administration (BPA) project number 1988- 053-03, contract number 50150). A previous agreement between Oregon Department of Fish and Wildlife (ODFW) and USGS-CRRL had funded materials acquisition, construction, and installation of the PTIS (BPA project number 1988-053-04, contract number 48684). The primary purpose of the project was to test the efficacy of a PTIS in the lower Hood River for providing data on returning adult salmonids to the Hood River as part of the Hood River Production Monitor and Evaluation project (HRPME). Because PIT tags are small, relatively inexpensive, carry no internal battery, and last through the lifespan of most fishes, they are commonly used in long term fish monitoring projects. They have been extensively used in the Columbia River basin to monitor salmonid behavior and survival through life stages and migration routes in the mainstem Columbia River (Skalski et al. 1998; Zabel and Achord 2004). Increasingly, PIT-tag detection equipment has been deployed in streams to investigate salmonid behavior (Zydlewski et al. 2001, 2006; Riley et al. 2003; Bond et al. 2007). Most of the detection systems deployed and evaluated to date have been in much smaller streams than the mainstem of the Hood River (Zydlewski et al. 2001, 2006; Bond et al. 2007; Horton et al. 2007; Connolly et al. 2008), but researchers are attempting to expand detection abilities to larger streams and rivers. Large streams and rivers can prove extremely challenging to monitor. Some systems have showed promise for contributing valuable detection data, others have proved less successful. A detection system in the Klamath River (Beeman et al. 2012), a site similar in size to the Hood River, suffered problems from cables being dislodged and high water that resulted in a detection efficiency estimate for juvenile coho salmon of less than 0.05. An additional USGS-CRRL task, under contract number 50150, was to build three antennas for use with Destron-Fearing 2001F-ISO PIT tag readers. These antennas would be 5 used at the East Fork Hood River Acclimation site. They would be placed in the outflow channel to inform managers about the number of PIT tagged steelhead smolts released to the Hood River after a period of acclimation when some mortality and predation might occur.

Oregon

Wind River watershed restoration: Annual report of U.S. Geological Survey activities November 2010 – October 2011

This report summarizes work completed by U.S. Geological Survey’s Columbia River Research Laboratory (USGS-CRRL) in the Wind River subbasin during November 2010 through October 2011 under Bonneville Power Administration (BPA) contract 40481. The primary focus of USGS activities during this contract was on tagging of juvenile steelhead Oncorhynchus mykiss with Passive Integrated Transponder (PIT) tags, and working toward a network of instream PIT tag detection systems to monitor movements and life histories of these fish.

Report

Estimating the hatchery fraction of a natural population: a Bayesian approach

There is strong and growing interest in estimating the proportion of hatchery fish that are in a natural population (the hatchery fraction). In a sample of fish from the relevant population, some are observed to be marked, indicating their origin as hatchery fish. The observed proportion of marked fish is usually less than the actual hatchery fraction, since the observed proportion is determined by the proportion originally marked, differential survival (usually lower) of marked fish relative to unmarked hatchery fish, and rates of mark retention and detection. Bayesian methods can work well in a setting such as this, in which empirical data are limited but for which there may be considerable expert judgment regarding these values. We explored a Bayesian estimation of the hatchery fraction using Monte Carlo–Markov chain methods. Based on our findings, we created an interactive Excel tool to implement the algorithm, which we have made available for free.

North American Journal of Fisheries Management

Big Spring spinedace and associated fish populations and habitat conditions in Condor Canyon, Meadow Valley Wash, Nevada

Executive Summary: This project was designed to document habitat conditions and populations of native and non-native fish within the 8-kilometer Condor Canyon section of Meadow Valley Wash, Nevada, with an emphasis on Big Spring spinedace (Lepidomeda mollispinis pratensis). Other native fish present were speckled dace (Rhinichthys osculus) and desert sucker (Catostomus clarki). Big Spring spinedace were known to exist only within this drainage and were known to have been extirpated from a portion of their former habitat located downstream of Condor Canyon. Because of this extirpation and the limited distribution of Big Spring spinedace, the U.S. Fish and Wildlife Service listed this species as threatened under the Endangered Species Act in 1985. Prior to our effort, little was known about Big Spring spinedace populations or life histories and habitat associations. In 2008, personnel from the U.S. Geological Survey's Columbia River Research Laboratory began surveys of Meadow Valley Wash in Condor Canyon. Habitat surveys characterized numerous variables within 13 reaches, thermologgers were deployed at 9 locations to record water temperatures, and fish populations were surveyed at 22 individual sites. Additionally, fish were tagged with Passive Integrated Transponder (PIT) tags, which allowed movement and growth information to be collected on individual fish. The movements of tagged fish were monitored with a combination of recapture events and stationary in-stream antennas, which detected tagged fish. Meadow Valley Wash within Condor Canyon was divided by a 12-meter (m) waterfall known as Delmue Falls. About 6,100 m of stream were surveyed downstream of the falls and about 2,200 m of stream were surveyed upstream of the falls. Although about three-quarters of the surveyed stream length was downstream of Delmue Falls, the highest densities and abundance of native fish were upstream of the falls. Big Spring spinedace and desert sucker populations were highest near the upper end of Condor Canyon, where a tributary known as Kill Wash, and several springs, contribute flow and moderate high and low water temperature. Kill Wash and the area around its confluence with Meadow Valley Wash appeared important for spawning of all three native species. Detections of PIT-tagged fish indicated that there were substantial movements to this area during the spring. Our surveys included about 700 m of Meadow Valley Wash upstream of Kill Wash. A small falls about 2 m high was about 560 m upstream of Kill Wash. This falls is likely a barrier to upstream fish movement at most flows. Populations of all three native species were found upstream of this small falls. Age-0 fish of all three species were present, indicating successful spawning. The maximum upstream extent of native fish within Meadow Valley Wash was not determined. Our surveys included about 700 m of Meadow Valley Wash upstream of Kill Wash. A small falls about 2 m high was about 560 m upstream of Kill Wash. This falls is likely a barrier to upstream fish movement at most flows. Populations of all three native species were found upstream of this small falls. Age-0 fish of all three species were present, indicating successful spawning. The maximum upstream extent of native fish within Meadow Valley Wash was not determined. A population of non-native rainbow trout (Oncorhynchus mykiss) was found within the 2,000 m of stream immediately downstream of Delmue Falls. Non-native crayfish were very common both upstream and downstream of Delmue Falls. We were not able to quantify crayfish populations, but they compose a significant portion of the biomass of aquatic species in Condor Canyon. There were some distinctive habitat features that may have favored native fish upstream of Delmue Falls. Upstream of the falls, water temperatures were moderated by inputs from springs, turbidity was lower, pool habitat was more prevalent, substrate heterogeneity was higher, and there was less fine sediment than

Open-File Report

Composition and relative abundance of fish species in the lower White Salmon River, Washington, prior to the removal of Condit Dam

Information about the composition and relative abundance of fish species was collected by a rotary screw trap and backpack electrofishing in the lower White Salmon River, Washington. The information was collected downstream of Condit Dam, which is at river kilometer (rkm) 5.2, and is proposed for removal in October 2011. A rotary screw trap was installed in the White Salmon River at rkm 1.5 and operated from March through June during 2006–09. All captured fish were identified to species and enumerated. Daily subsets of fish were weighed, measured, and fin clipped for a genetic analysis by the U.S. Fish and Wildlife Service. Fall Chinook salmon ( Oncorhynchus tshawytscha ) were captured in the highest numbers (n=18, 640), and were composed of two stocks: tule and upriver bright. Almost all captured fall Chinook salmon were age-0, with only 16 (0.09 percent) being age-1 or older. Tule fall Chinook salmon, the native stock, generally out-migrated from mid-March through early April. The tule stock was the more abundant fall Chinook salmon subspecies, comprising 85 percent of those captured in the trap. Upriver bright fall Chinook salmon comprised 15 percent of the Chinook salmon catch and generally out-migrated from late May to early June. Coho salmon ( kisutch ) and steelhead trout ( O. mykiss ) were captured by the rotary screw trap in all years. Coho salmon were caught in low numbers (n=661) and 69 percent were age-0 fish. Steelhead were slightly more abundant (n=679) than coho salmon and 84 percent were age-1 or older fish. Trap efficiency estimates varied widely (range, 0-10 percent) by species, fish size, and time of year. However, if we use only the estimates from efficiency tests where more than 300 wild age-0 Chinook salmon were released, there was a mean trapping efficiency of 1.4 percent (n=4, median, 1.3 percent, range, 0.3–2.4 percent) during the tule out-migration period, and a mean trapping efficiency of 0.8 percent (n=2, range, 0.3–1.2 percent) during the upriver bright fall Chinook salmon out-migration period. When water levels in the White Salmon River declined in late summer, we electrofished the river margins in 2006–09 along three sites at rkm 1.5, 2.3, and 4.2. Age-0 steelhead were the most abundant fish captured (n=565, 62 percent), followed by age-0 coho salmon (n=222, 24 percent). In autumn, age-0 Chinook salmon were collected while electrofishing (n=40, 4 percent). This suggests that there may be a migration in the autumn as age-0 Chinook salmon or in the spring as age-1 Chinook salmon, since the Chinook salmon that migrate as age-0 fish in the spring departed several months earlier (the typical life history for fall Chinook salmon). The only age-1 salmonids captured while electrofishing were steelhead (n=84, 9 percent). Fish distribution and abundance will likely change when Condit Dam is removed and anadromous fish gain access to their historical spawning and rearing areas in the White Salmon River. These findings should provide a baseline with which to compare juvenile fish species composition and relative abundance after Condit Dam is removed.

Washington

Movement of bull trout in the upper Jarbidge River watershed, Idaho and Nevada, 2008-09--A supplement to Open-File Report 2010-1033

We monitored bull trout ( Salvelinus confluentus ) in 2008 and 2009 as a continuation of our work in 2006 and 2007, which involved the tagging of 1,536 bull trout with passive integrated transponder (PIT) tags in the East Fork Jarbidge River and West Fork Jarbidge River and their tributaries in northeastern Nevada and southern Idaho. We installed PIT tag interrogation systems (PTISs) at established locations soon after ice-out, and maintained the PTISs in order to collect information on bull trout movements through December of each year. We observed a marked increase of movement in 2008 and 2009. Bull trout tagged in the uppermost portions of the East Fork Jarbidge River at altitudes greater than 2,100 meters moved to the confluence of the East Fork Jarbidge River and West Fork Jarbidge River in summer and autumn. Ten bull trout tagged upstream of the confluence of Pine Creek and the West Fork Jarbidge River moved downstream and then upstream in the East Fork Jarbidge River, and then past the PTIS at Murphy Hot Springs (river kilometer [rkm] 4.1). Two of these fish ascended Dave Creek, a tributary of the East Fork Jarbidge River, past the PTIS at rkm 0.4. One bull trout that was tagged at rkm 11 in Dave Creek on June 28, 2007 moved downstream to the confluence of the East Fork Jarbidge River and West Fork Jarbidge River (rkm 0) on July 28, 2007, and it was then detected in the West Fork Jarbidge River moving past our PTIS at rkm 15 on May 4, 2008. Combined, the extent and types of bull trout movements observed indicated that the primarily age-1 and age-2 bull trout that we tagged in 2006 and 2007 showed increased movement with age and evidence of a substantial amount of fluvial life history. The movements suggest strong connectivity between spawning areas and downstream mainstem areas, as well as between the East Fork Jarbidge River and West Fork Jarbidge River.

Open-File Report

Effectiveness of a redesigned water diversion using rock vortex weirs to enhance longitudinal connectivity for small Salmonids

For nearly 100 years, water diversions have affected fish passage in Beaver Creek, a tributary of the lower Methow River in north-central Washington State. From 2000 to 2004, four dam-style water diversions were replaced with a series of rock vortex weirs (RVWs). The weirs were designed to allow fish passage while maintaining the ability to divert water into irrigation canals. We observed the new appearance of three species (juvenile Chinook salmon Oncorhynchus tshawytscha , juvenile coho salmon O. kisutch , and mountain whitefish Prosopium williamsoni ) upstream of the RVWs, indicating successful restoration of longitudinal connectivity. We used passive integrated transponder (PIT) tags and instream PIT tag interrogation systems during 2004–2007 to evaluate upstream passage of small salmonids (<240 mm fork length) through one series of RVWs. We documented 109 upstream passage events by small salmonids through the series of RVWs; most of the events (81%) involved passage of rainbow trout O. mykiss or juvenile steelhead (anadromous rainbow trout). Small rainbow trout or steelhead ranging from 86 to 238 mm (adjusted fork length) were able to pass upstream through the RVWs, although a delay in fish passage at discharges below 0.32 m 3 /s was detected in comparison with nearby control sections.

Washington

Distribution and movement of bull trout in the upper Jarbidge River watershed, Nevada

In 2006 and 2007, we surveyed the occurrence of bull trout ( Salvelinus confluentus ), the relative distributions of bull trout and redband trout ( Oncorhynchus mykiss ), and stream habitat conditions in the East and West Forks of the Jarbidge River in northeastern Nevada and southern Idaho. We installed passive integrated transponder (PIT) tag interrogation systems at strategic locations within the watershed, and PIT-tagged bull trout were monitored to evaluate individual fish growth, movement, and the connectivity of bull trout between streams. Robust bull trout populations were found in the upper portions of the East Fork Jarbidge River, the West Fork Jarbidge River, and in the Pine, Jack, Dave, and Fall Creeks. Small numbers of bull trout also were found in Slide and Cougar Creeks. Bull trout were numerically dominant in the upper portions of the East Fork Jarbidge River, and in Fall, Dave, Jack, and Pine Creeks, whereas redband trout were numerically dominant throughout the rest of the watershed. The relative abundance of bull trout was notably higher at altitudes above 2,100 m. This study was successful in documenting bull trout population connectivity within the West Fork Jarbidge River, particularly between West Fork Jarbidge River and Pine Creek. Downstream movement of bull trout to the confluence of the East Fork and West Fork Jarbidge River both from Jack Creek (rkm 16.6) in the West Fork Jarbidge River and from Dave Creek (rkm 7.5) in the East Fork Jarbidge River was detected. Although bull trout exhibited some downstream movement during the spring and summer, much of their emigration occurred in the autumn, concurrent with decreasing water temperatures and slightly increasing flows. The bull trout that emigrated were mostly age-2 or older, but some age-1 fish also emigrated. Upstream movement by bull trout was detected less than downstream movement. The overall mean annual growth rate of bull trout in the East Fork and West Fork Jarbidge River was 36 mm. This growth rate is within the range reported in other river systems and is indicative of good habitat conditions. Mark-recapture methods were used to estimate a population of 147 age-1 or older bull trout in the reach of Jack Creek upstream of Jenny Creek.

Open-File Report

Guidelines to indirectly measure and enhance detection efficiency of stationary PIT tag interrogation systems in streams

With increasing use of passive integrated transponder (PIT) tags and reliance on stationary PIT tag interrogation systems to monitor fish populations, guidelines are offered to inform users how best to use limited funding and human resources to create functional systems that maximize a desired level of detection and precision. The estimators of detection efficiency and their variability as described by Connolly et al. (2008) are explored over a span of likely performance metrics. These estimators were developed to estimate detection efficiency without relying on a known number of fish passing the system. I present graphical displays of the results derived from these estimators to show the potential efficiency and precision to be gained by adding an array or by increasing the number of PIT-tagged fish expected to move past an interrogation system.

Book chapter

Guidelines to indirectly measure and enhance detection efficiency of stationary PIT tag interrogation systems in streams

With increasing use of passive integrated transponder (PIT) tags and reliance on stationary PIT tag interrogation systems to monitor fish populations, guidelines are offered to inform users how best to use limited funding and human resources to create functional systems that maximize a desired level of detection and precision. The estimators of detection efficiency and their variability as described by Connolly et al. (2008) are explored over a span of likely performance metrics. These estimators were developed to estimate detection efficiency without relying on a known number of fish passing the system. I present graphical displays of the results derived from these estimators to show the potential efficiency and precision to be gained by adding an array or by increasing the number of PIT-tagged fish expected to move past an interrogation system.

Book chapter