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Katrina E. Simmons

Publications and source records attributed to Katrina E. Simmons.

2 recordsLinked to original sources
USGS2012

Assessing fish predation on migrating juvenile steelhead and a retrospective comparison to steelhead survival through the Priest Rapids Hydroelectric Project, Columbia River, Washington, 2009-11

The U.S. Geological Survey (USGS) and the Washington Department of Fish and Wildlife (WDFW) have been working with the Public Utility District No. 2 of Grant County, Washington (Grant PUD), to increase their understanding of predator-prey interactions in the Priest Rapids Hydroelectric Project (PRP), Columbia River, Washington. For this study, the PRP is defined as the area approximately 6 kilometers upstream of Wanapum Dam to the Priest Rapids Dam tailrace, 397.1 miles from the mouth of the Columbia River. Past year’s low survival numbers of juvenile steelhead ( Oncorhynchus mykiss ) through Wanapum and Priest Rapids Dams has prompted Grant PUD, on behalf of the Priest Rapids Coordinating Committee, to focus research efforts on steelhead migration and potential causal mechanisms for low survival. Steelhead passage survival in 2009 was estimated at 0.944 through the Wanapum Development (dam and reservoir) and 0.881 through the Priest Rapids Development and for 2010, steelhead survival was 0.855 for Wanapum Development and 0.904 for Priest Rapids Development. The USGS and WDFW implemented field collection efforts in 2011 for northern pikeminnow ( Ptychocheilus oregonensis ), smallmouth bass ( Micropterus dolomieu ), and walleye ( Sander vitreus , formerly Stizostedion vitreum ) and their diets in the PRP. For predator indexing, we collected 948 northern pikeminnow, 237 smallmouth bass, 18 walleye, and two largemouth bass ( Micropterus salmoides ). The intent of this study was to provide standardized predation indices within individual reaches of the PRP to discern spatial variability in predation patterns. Furthermore, the results of the 2011 study were compared to results of a concurrent steelhead survival study. Our results do not indicate excessively high predation of Oncorhynchus spp. occurring by northern pikeminnow or smallmouth bass in any particular reach throughout the study area. Although we found Oncorhynchus spp. in the predator diets, the relative proportion was small. Predation index values in 2011 were highest in the Priest Rapids mid-reservoir reach for northern pikeminnow and smallmouth bass. Predation indices generally were high in the tailrace areas for northern pikeminnow, and high in the forebay areas for smallmouth bass. Steelhead survival in 2011 was consistently high throughout the study period and the PRP, although predation indices were relatively low, which suggests that fish predation did not significantly affect steelhead survival throughout the study area. Our efforts to correlate retrospective predation indices with survival estimates for 2009 and 2010 did provide some evidence for high predation occurring in some of the same reaches, which had low steelhead survival, such as the Priest Rapids tailrace in 2009. However, for 2010, our results indicated that the loss of salmonids to predation were more contradictory to the survival results, where predation indices were higher for reaches in the Priest Rapids Development than in the Wanapum Development. Establishing correlations between steelhead survival and observed predation indices for previous research years, in 2009 and 2010 was confounded by the lack of coordination of these two studies during the initial study design, implementation period for such an analysis. Future efforts to correlate steelhead survival with fish predation would benefit from efforts to better coordinate the studies with consistent study reaches, and better timing of concurrent efforts.

Washington↗
USGS2012

Assessing native and introduced fish predation on migrating juvenile salmon in Priest Rapids and Wanapum Reservoirs, Columbia River, Washington, 2009--11

Hydroelectric development on the mainstem Columbia River has created a series of impoundments that promote the production of native and non-native piscivores. Reducing the effects of fish predation on migrating juvenile salmonids has been a major component of mitigating the effects of hydroelectric development in the Columbia River basin. Extensive research examining juvenile salmon predation has been conducted in the lower Columbia River. Fewer studies of predation have been done in the Columbia River upstream of its confluence with the Snake River; the most comprehensive predation study being from the early 1990s. The Public Utility District No. 2 of Grant County, Washington initiated a northern pikeminnow removal program in 1995 in an attempt to reduce predation on juvenile salmonids. However, there has been no assessment of the relative predation within the Priest Rapids Project since the removal program began. Further, there is concern about the effects of piscivores other than northern pikeminnow ( Ptychocheilus oregonensis ), such as channel catfish ( Ictalurus punctatus ), smallmouth bass ( Micropterus dolomieu ), and walleye ( Sander vitreus , formerly Stizostedion vitreum ). The Public Utility District No. 2 of Grant County, Washington and the Priest Rapids Coordinating Committee requested that the U.S. Geological Survey, in collaboration with the Washington Department of Fish and Wildlife, assist them in evaluating the effects of native and introduced predatory fish on migrating juvenile salmon. From 2009 to 2010, we conducted sampling in the 103 kilometers (64 river miles) of the Columbia River from the tailrace of Rock Island Dam downstream to the tailrace of Priest Rapids Dam. To assess predation, we used electrofishing to collect northern pikeminnow, smallmouth bass, and walleye to analyze their diets during 2009 and 2010. In 2009, we used methods to allow comparisons to a previous study conducted in 1993. During 2009, we also used an alternate sampling strategy using habitat data and geographic information system software to select sites and allocate samples. In 2010, we used the data collected during 2009 to further refine our sampling design, with the intent of using the data collected during 2010 to formulate a design strategy for implementation during 2011. Based on the results of 2011, we would then propose a strategy for future studies. However, during 2011, our efforts were redirected to specifically address factors that may be affecting steelhead trout survival in the Priest Rapids Reservoir, Columbia River. We used the catch and diet data collected in 2009 and 2010 to estimate relative abundance, consumption, and predation indices for northern pikeminnow and smallmouth bass. Despite extensive sampling in the study area in 2009 and 2010, very few channel catfish and walleye were captured. The mean total lengths of northern pikeminnow were much lower than those observed in 1993; suggesting that efforts to remove northern pikeminnow in the study area may be shifting the population towards smaller fish. The northern pikeminnow predation index values were lower in 2009 than in the 1993 study. The reduced predation levels observed may be due to the prevalence of smaller pikeminnow in our catches than in catches reported in 1993. Predation by smallmouth bass was lower in 2009 than in 2010, and generally was greater than predation for northern pikeminnow. Predation for northern pikeminnow was concentrated in the tailrace areas of Priest Rapids, Wanapum, and Rock Island Dams; predation for smallmouth bass was concentrated in the forebay and mid-reservoir sections of the study area. Our results indicate areas where control measures for smallmouth bass could be concentrated to reduce predation in the Priest Rapids Project.

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