20 research outputs found
Rising land falling fishery: the effects of isostatic rebound and rapid succession on east Alsek River sockeye salmon
Thesis (M.S.) University of Alaska Fairbanks, 2008This thesis includes research conducted in the Dry Bay Preserve of Glacier Bay National Park in 2005 and 2006 for the U.S. National Park Service. The research mission was to determine the cause of collapse in the East Alsek commercial sockeye fishery. The focus of the study was to determine if the collapse was due to human caused events or if there was a broader ecological basis for the recent downturn in returning sockeye. The East Alsek had undergone a dramatic decline in returning sockeye in recent years and the changing quality and quantity of habitat was thought to be the culprit for this downturn. However, fishery records and other environmental variables were also examined in order to establish a retrospective association between reduced production, ambient environmental conditions, and commercial fishing. The research for this thesis was funded by the U.S. National Park Service under the request of the City and Borough of Yakutat
Ecological effects of reservoir operations on Blue Mesa Reservoir
Includes bibliographical references.Annual progress report, May 1, 1995-April 30, 1996
Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at Bonneville Dam, Spring 2010
The purpose of this study was to estimate the survival for yearling Chinook salmon and steelhead smolts during spring 2010 in a portion of the Columbia River that includes Bonneville Dam. The study estimated smolt survival from a virtual release at Bonneville Dam to a survival array 81 km downstream of Bonneville Dam. We also estimated median forebay residence time, median tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. A single release design was used to estimate survival from Bonneville Dam to a primary array located 81 km downstream of Bonneville. The approach did not include a reference tailrace release. Releases of acoustic-tagged smolts above John Day Dam to Hood River contributed to the formation of virtual releases at a Bonneville Dam forebay entrance array and at the face of the dam. A total of 3,880 yearling Chinook salmon and 3,885 steelhead smolts were tagged and released in the investigation. The Juvenile Salmon Acoustic Telemetry System (JSATS) tag model number ATS-156dB, weighing 0.438 g in air, was used in this investigation
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The Feasibility of Using an Ultrasonic Fish Tracking System in the Tailrace of Lower Granite Dam in 2002
This report describes a study conducted by PNNL in Spring 2002 at Lower Granite Dam on the Snake River for the US Army Corps of Engineers Portland District. Our goal was to determine the feasibility of using ultrasonic fish tracking in the untested environment of a hydroelectric dam tailrace. If fish tracking were determined to be feasible, we would track the movement of juvenile hatchery chinook (Oncorhynchus tshawytscha), juvenile hatchery steelhead (O. mykiss), and juvenile wild steelhead (O. mykiss) and relate their movement to dam operations. The majority of fish to be tracked were released as a part of a separate study conducted by the Biological Resources Division of the U.S. Geological Survey (BRD), which was investigating the movement of juvenile salmon in the forebay of Lower Granite Dam in relation to Removable Spillway Weir (RSW) testing. The two studies took place consecutively from April 14 to June 7, 2002
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Optimization of Concurrent Deployments of the Juvenile Salmon Acoustic Telemetry System and Other Hydroacoustic Equipment at John Day Dam
The purpose of this report is to document the results of the acoustic optimization study conducted at John Day Dam during January and February 2008. The goal of the study was to optimize performance of the Juvenile Salmon Acoustic Telemetry System (JSATS) by determining deployment and data acquisition methods to minimize electrical and acoustic interference from various other acoustic sampling devices. Thereby, this would allow concurrent sampling by active and passive acoustic methods during the formal evaluations of the prototype surface flow outlets at the dam during spring and summer outmigration seasons for juvenile salmonids. The objectives for the optimization study at John Day Dam were to: 1. Design and test prototypes and provide a total needs list of pipes and trolleys to deploy JSATS hydrophones on the forebay face of the powerhouse and spillway. 2. Assess the effect on mean percentage decoded of JSATS transmissions from tags arrayed in the forebay and detected on the hydrophones by comparing: turbine unit OFF vs. ON; spill bay OPEN vs. CLOSED; dual frequency identification sonar (DIDSON) and acoustic Doppler current profiler (ADCP) both OFF vs. ON at a spill bay; and, fixed-aspect hydroacoustic system OFF vs. ON at a turbine unit and a spill bay. 3. Determine the relationship between fixed-aspect hydroacoustic transmit level and mean percentage of JSATS transmissions decoded. The general approach was to use hydrophones to listen for transmissions from JSATS tags deployed in vertical arrays in a series perpendicular to the face of the dam. We used acoustic telemetry equipment manufactured by Technologic and Sonic Concepts. In addition, we assessed old and new JSATS signal detectors and decoders and two different types of hydrophone baffling. The optimization study consisted of a suite of off/on tests. The primary response variable was mean percentage of tag transmissions decoded. We found that there was no appreciable adverse effect on mean percentage decoded for JSATS transmitters from: turbine operations; spillway operations; DIDSON/ADCP acoustic energy; and PAS hydroacoustic systems at transmit level of -12 dB, although there was a significant impact at all higher transmit levels (-11 to -6 dB). The main conclusion from this optimization study is that valid JSATS telemetry data can be collected simultaneously with a DIDSON/ADCP and a PAS hydroacoustic system at transmit level -12 dB. Multiple evaluation tools should be considered to increase the robustness and thoroughness of future fish passage evaluations at John Day and other dams
Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2010
Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams
The genetic architecture of the human cerebral cortex
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder
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Evaluation of the Fish Passage Effectiveness of the Bonneville I Prototype Surface Collector using Three-Dimensional Ultrasonic Fish Tracking
This report describes tests conducted at Bonneville Dam on the Columbia River in the spring of 2000 using three-dimensional acoustic telemetry and computational fluid dynamics hydraulic modeling to observe the response of outmigrating juvenile steelhead and yearling chinook to a prototype surface collector installed at the Powerhouse. The study described in this report was one of several conducted for the U.S. Army Corps of Engineers to prepare a decision document on which of two bypass methods: surface flow bypass or extended-length submersible bar screens to use to help smolts pass around Bonneville dams without going through the turbines
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Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at Bonneville Dam, Spring 2010
The purpose of this study was to estimate the survival for yearling Chinook salmon and steelhead smolts during spring 2010 in a portion of the Columbia River that includes Bonneville Dam. The study estimated smolt survival from a virtual release at Bonneville Dam to a survival array 81 km downstream of Bonneville Dam. We also estimated median forebay residence time, median tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. A single release design was used to estimate survival from Bonneville Dam to a primary array located 81 km downstream of Bonneville. The approach did not include a reference tailrace release. Releases of acoustic-tagged smolts above John Day Dam to Hood River contributed to the formation of virtual releases at a Bonneville Dam forebay entrance array and at the face of the dam. A total of 3,880 yearling Chinook salmon and 3,885 steelhead smolts were tagged and released in the investigation. The Juvenile Salmon Acoustic Telemetry System (JSATS) tag model number ATS-156dB, weighing 0.438 g in air, was used in this investigation
Recommended from our members
Evaluation of the Fish Passage Effectiveness of the Bonneville I Prototype Surface Collector using Three-Dimensional Ultrasonic Fish Tracking
This report describes tests conducted at Bonneville Dam on the Columbia River in the spring of 2000 using three-dimensional acoustic telemetry and computational fluid dynamics hydraulic modeling to observe the response of outmigrating juvenile steelhead and yearling chinook to a prototype surface collector installed at the Powerhouse. The study described in this report was one of several conducted for the U.S. Army Corps of Engineers to prepare a decision document on which of two bypass methods: surface flow bypass or extended-length submersible bar screens to use to help smolts pass around Bonneville dams without going through the turbines