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Articles 1 - 5 of 5
Full-Text Articles in Life Sciences
Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh
Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh
Watershed Sciences Faculty Publications
Historically, thousands of Snake River Sockeye salmon returned to the Sawtooth Valley to spawn. Evermann (1896) reported that the Sawtooth Valley Lakes were teeming with red fish. Bjornn (196~) estimated that 4,360 sockeye returned to Redfish Lake in 1955. These numbers no longer exist. In the 1980's, less than 50 Snake River sockeye salmon survived to spawn (Bowler 1990). Since 19-90, only 13 sockeye have returned. Because of recent declines, the Shoshone-Bannock Tribes (SBT) petitioned the National Marine Fisheries Service (NMFS-) to list Snake River sockeye as endangered. As a result, Snake River sockeye were listed and the Bonneville Power …
Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service
Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service
Environmental Assessments (NV)
No abstract provided.
Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh
Effects Of Moonlight And Daylight On Hydroacoustic Estimates Of Pelagic Fish Abundance, Chris Luecke, Wayne A. Wurtsbaugh
Watershed Sciences Faculty Publications
To determine how moonlight and daylight affect hydroacoustic estimates of fish abundance, we used a dual-beam transducer and echo integration to survey pelagic fish (primarily Bonneville ciscoes Prosopium gemmifer) in Bear Lake, Utah and Idaho. During the new moon, the fish were dispersed (not schooling) below the thermocline, chiefly at the depths of 10–20 m. At full moon, they were dispersed but much closer to the bottom, where they were difficult to detect. Acoustic estimates offish density and biomass during full moons were approximately 50% of values derived during new moons. A diel survey during a new moon indicated that …
An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh
An Empirical Model Of Gastric Evacuation Rates For Fish And An Analysis Of Digestion In Piscivorous Brown Trout, E. He, Wayne A. Wurtsbaugh
Watershed Sciences Faculty Publications
The gastric evacuation rates of brown trout Salmo trutta (0.9–1.6 kg) feeding on fingerling rainbow trout Oncorhynchus mykiss (3.5–7.6 g) were measured in the laboratory at five temperatures (4.5, 9.0, 14.0, 19.0, and 22.5°C). Instantaneous gut evacuation rates (Re) increased exponentially with temperature (T): Re = 0.053se^0.073T, r^2 = 0.98; they varyied from 7%sh^–1 at 4.5°C to 29%sh^–1 at 22.5°C. Linear regressions described the relationship between time and qualitative measures of fish digestion, thus allowing investigators to determine how long an ingested fish would be identifiable at different temperatures. An analysis of published evacuation rates (N = 121) of 22 …
Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service
Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service
Environmental Assessments (NV)
No abstract provided.