Aquaculture and Fisheries Commons^™

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 …

The Influence Of Redd Distribution And Microhabitat Availability On The Distribution And Abundance Of Young-Of-The-Year Trout In The Green River, Utah, Michael J. Buntjer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Redd distribution, redd density, and physical habitat were used to explain the distribution and abundance of young-of-the-year (YOY) brown trout (Salmo trutta) and rainbow trout (Oncorhynchus mykiss) in the Green River, Utah. The importance of variables at both a microhabitat and macrohabitat scale were assessed using stepwise regression analysis. Availability of cover (rock and vegetation) and proximity to spawning sites were the most important variables used to explain the distribution and abundance of YOY brown trout and rainbow trout. In addition, YOY brown trout and rainbow trout occupied specific microhabitats and showed patterns of use for …

Visual Feeding By Juvenile Bear Lake Sculpin, D. Neverman, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Young-of-the-year Bear Lake sculpin Cottus extensus feed throughout the day on benthic invertebrates and cease feeding at night when they migrate to the metalimnion. We investigated their reliance on vision by conducting feeding trials at different light levels in the laboratory. Feeding rate reached a maximum at intermediate light levels (near 10^16 photons sm^–2 ss^–1; approximately 1 lux) but decreased as light intensity increased beyond this range. At this maximum rate, the fish fed nine times faster than they were able to feed in the dark, showing that young Bear Lake sculpin rely heavily upon vision to feed. The light …

A Trophic Gradient Analysis Of Lake Powell During Spring Runnoff 1992, Wayne A. Wurtsbaugh, Clyde Lay, Darren Carlise, Corey Huxol, Craig Schaugaard, Beau Clements, David Beauchamp

Watershed Sciences Faculty Publications

Between 26 April and 2 May 1992, students in a utah state university aquatic ecology class visited Lake Powell to do a study of trophic gradients of the reservoir. The main axis of the reservoir was surveyed, as well as less detailed analyses of Moki and Escalante Canyons. The work was conducted in collaboration with personnel from the u.s. Bureau of Reclamation headed by Bill Vernieu, and from the u.s. Geological Survey (Dick Marzolf). Some of their data appear in the physical-chemical section of this report.

Each student was responsible for compiling a report on one of the following specific …

Snake River Sockeye Salmon (Oncorhynchus Nerka) Habitat/Limnologic Research, Scott Spaulding, Wayne A. Wurtsbaugh, Shoshone-Bannock Tribe

Watershed Sciences Faculty Publications

This report outlines long-term planning and monitoring activities that occurred in 1991 and 1992 in the Stanley Basin Lakes of the upper Salmon River, Idaho for the purpose of sockeye salmon (Oncorhynchus nerka) recovery. Limnological monitoring and experimental sampling protocol, designed to establish a limnological baseline and to evaluate sockeye salmon production capability of the lakes, are present:ed. Also presented are recommended passage improvements for current fish passage barriers/impediments on migratory routes to the lakes. We initiated O. Nerka population evaluations for Redfish and Alturas lakes; this included population estimates of emerging kokanee fry entering each lake in the spring …

Lake Trout Spawning In Lake Tahoe: Egg Incubation In Deepwater Macrophyte Beds, D. A. Beauchamp, B. C. Allen, R. C. Richards, Wayne A. Wurtsbaugh, C. R. Goldman

Watershed Sciences Faculty Publications

Although most populations of lake trout Salvelinus namaycush spawn over rocky shoals, use of these substrates by lake trout has not yet been found in Lake Tahoe. Large cobble substrate exists at depths less than 20 m, and steep, fractured, rocky substrate can be found in isolated areas from the surface down to at least 100 m, but no evidence of spawning activity in these areas has been found. Instead, at least a portion of the population spawns on deepwater mounds (40–60 m deep) over beds of the macrophyte Chara delicatula. This is the first known report of lake trout …

Investigations Of Forage Fish And Lake Trout Salvelinus Namaycush Interactions In Flaming Gorge Reservoir, Wyoming-Utah, Daniel L. Yule

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated the interaction of lake trout (Salvelinus namaycush) and their dominant forage fish populations, Utah chub (Gila atraria) and kokanee salmon (Oncorhynchus nerka), in Flaming Gorge Reservoir, Wyoming-Utah. Through bioenergetics modeling, I quantified the consumption dynamics of the lake trout population. From hydroacoustics analyses, I quantified the density and biomass of the two dominant forage fish populations.

In Chapter II, I report the results of the energetics analysis. The objective of this chapter was to understand the role of lake trout predation in recent changes in fish assemblage structure of the reservoir. Through …

Winter Habitat Selection Of Cutthroat Trout (Oncorhynchus Clarki) In A Large Regulated River, Ronald A. Englund

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microhabitat use by cutthroat trout and macrohabitat use by both cutthroat and rainbow trout were studied i n the Green River below Flaming Gorge Dam during the winters of 1988 and 1989. Microhabitat parameters used by cutthroat trout, such as focal velocity, depth, and fish elevation, differed significantly in eddies, runs, and riffles. Mean focal velocities in runs were 0.79 body lengths/seconds (bl/s), in riffles 0.66 bl/s, and in eddies 0.24 bl/s. Cutthroat trout size also varied significantly with macrohabitat; larger fish were found in riffles.

Macrohabitat use by cutthroat trout and rainbow trout differed significantly among species, macrohabitat types, …

Is Rainbow Trout Condition Influenced By Invertebrate-Drift Density?, Randall B. Filbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Users of the Instream Flow Incremental Methodology CTFIM) commonly assume that there is a positive linear relationship between available habitat (WUA) and stream fish biomass. However, several studies have shown a lack cf correlation between WUA and biomass. Such poor relationships may occur if other factors limit fish abundance. Food availability is a potentially important factor limiting abundance of stream fishes and can affect blomass by influencing fish condition (individual weight). I collected rainbow trout (Oncorhynchus mykiss) exposed to different levels of invertebrate-drift density to determine if condition was greater where food was more abundant. I also examined …

Predation Risk And The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems, R. A. Tabor, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Juvenile rainbow trout Oncorhynchus mykiss stocked in midelevation reservoirs in Utah inhabit shallow nearshore areas and are vulnerable to predation from piscivorous fish and birds. We determined the use and importance of nearshore habitats by (1) measuring habitat selection by, prey availability to, and feeding of juvenile rainbow trout in two reservoirs with populations of predators, and (2) measuring survival and growth rates in the presence and absence of cover in a pond experiment where adult brown trout Salmo trutta were predators. In the reservoirs juvenile rainbow trout (60–120 mm standard length) were abundant in complex inshore habitats but avoided …

The Effects Of Disease, Prey Fluctuation, And Clear-Cutting On American Marten In Newfoundland, Canada, Richard J. Fredrickson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Individual variation in survival and behavior of American marten (Martes americana) was studied in relation to disease, prey fluctuation, and clear-cutting from 10 January 1986 through 20 August 1987 in Newfoundland, Canada. Thirty-seven of forty marten captured on the study area were telemetered and monitored for part or all of the study.

Marten mortality was concentrated in two intervals, fall 1986 and late winter 1987. Mortality during fall 1986 was attributable to encephalitis, while marten deaths during late winter 1987 resulted from predation and starvation attributable to the prey decline. Nonsuppurative encephalitis was first detected 7 October 1986; …

Recreation Specialization And Preferences Of Utah Anglers, Bruce P. Andersen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purposes of this study were to gain a better understanding of anglers and angler preferences and to examine differences between subgroups of anglers based on level of specialization. Understanding these similarities and differences between user groups will provide valuable input for more effective fisheries management.

A randomized mail survey was sent to resident, adult fishing-license holders in Utah. A 68% response rate yielded 1216 usable returns for data analysis. An analysis of three recreation specialization dimensions (participation, equipment and investment, and lifestyle) and further analysis of participation and investment variables were used to develop a typology of Utah anglers. …

The Importance Of Cover For Juvenile Rainbow Trout In Lentic Systems: Field Observations And An Experimental Study On Predation, Roger Allen Tabor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Juvenile rainbow trout Oncorhynchus mykiss stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by (1) direct observations (snorkel transects) of habitat selection in two reservoirs and (2) measurements of survival and growth rates in a pond experiment where adult brown trout Salmo trutta were predators. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day, juvenile trout were abundant in complex inshore habitats and avoided simple habitats such as sand and gravel. Measurements …

Survival Of Trout Strains As Affected By Limnological Parameters, Wayne A. Wurtsbaugh, Timothy Modde, Chris Luecke, Cheryl Courtney

Watershed Sciences Faculty Publications

Juvenile rainbow trout Oncorhynchus mykiss. (ca. 80 mm S.L.) stocked into mid-elevation reservoirs in Utah are vulnerable to predation from piscivorous fish and birds. I determined how effectively juvenile trout used cover to avoid these predators by using direct observations (snorkel transects) on habitat selection in two reservoirs. Observations of juvenile trout were conducted within five weeks of stocking in 1988 and 1989. During the day juvenile trout were abundant in complex inshore habitats. Juvenile trout actively fed during the day but the time of peak feeding was variable. Large Daphnia made of > 95% of the diet of juvenile trout. …

Trophic Interactions Between Fish And Invertebrates In Bear Lake, Utah-Idaho, Wayne A. Wurtsbaugh, Charles P. Hawkins

Watershed Sciences Faculty Publications

An intensive study of the limnology, invertebrates and fishes of Bear Lake was conducted in 1987 in order to define the productivity and food web of the community. Limno10gica1 parameters and invertebrates were measured at approximately monthly intervals while fish distribution and feeding was analyzed in February, June, August, and October. Samples were collected at three to eight stations along a transect running from the shallow littoral area on the west side of the lake, to the deep profundal zone.

Survival Of Trout Strains As Affected By Limnological Parameters, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Prior work at East Canyon Reservoir, Utah indicated that adult trout are important predators of stocked juvenile rainbow trout. Brown trout, in particular, were exclusively piscivorous when th~y exceeded 185 mm standard length. Fish became increasingly important in the diet of cutthroat trout greater than 330 mm. The purpose of this study was to further document the effect of adult trout on survival of juvenile rainbow trout in mid-elevation reservoirs. Causey Reservoir was chosen because it was thought to contain large brown and cutthroat trout and had not been intensively studied during the last eight years.

A Mass Mortality Of Fishes In Lake Titicaca (Peru-Bolivia) Associated With The Protozoan Parasite Ichthyophthirius Multifiliis, Wayne A. Wurtsbaugh, R. Alfaro

Watershed Sciences Faculty Publications

In December 1981 , an epizootic of the protozoan parasite Ichthyophthirius multifiliis killed an estimated 18 million killifish Orestias spp. in Lake Titicaca, a high-altitude tropical system. Of the dead fish collected, 93% were adult O. agassii, a commercially important species that is abundant in the littoral zone. Juvenile Orestias spp., pelagic species, and some other littoral zone fis hes were slightly affected. lchthyophthirius multifiliis was probably introduced with exotic fishes brought to Lake Titicaca in the 1940s and 1950s.

Importance Of Predation By Adult Trout On Mortality Rates Of Fingerling Rainbow Trout Stocked In East Canyon Reservoir, Utah, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Personnel from Utah State University, working in cooperation with the Utah Division of Wildlife Resources and the Utah Cooperative Fish and Wildlife Research Unit, are attempting to determine various sources of mortality of fingerling rainbow trout (Salmo gairdneri) stocked into mid-elevation reservoirs in the State. Returns of planted fish are often much below desired levels. Angler surveys indicate that in East Canyon Reservoir, fishermen harvest only about 30% of the fingerling trout stocked, and this is a much higher return than in many other waters.

Microhabitat Selection And Diel Movements Of Juvenile Rainbow Trout (Salmo Gairdneri) Introduced Into Mid-Elevation Reservoirs In Utah, Wayne A. Wurtsbaugh, Roger Tabor

Watershed Sciences Faculty Publications

The distribution and movement patterns of fingerling rainbow trout stocked into reservoirs in Utah were investigated with · SCUBA observations and by vertical gill netting. For several weeks after stocking, fingerling trout (ca. 80 mm standard length) were strongly oriented to the shore, and selected habitats providing cover. During the underwater observations, no fish were seen below depths of 2 meters. Two weeks after stocking, the fingerlings were most abundant under docks near where they were planted, indicating that dispersal was relatively slow. Jacob's electivity indices for natural substrates in water 0-1.5 meter deep were in sand, gravel, cobble, boulders …

Aspects Of The Feeding Ecology Of The Bonneville Cisco Of Bear Lake, Utah-Idaho, David C. Lentz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bonneville cisco (Prospium gemmiferum), a small planktivorous whitefish, is an important part of the distinctive fish community of Bear Lake, Utah-Idaho. The Bonneville cisco plays a key role in the trophic structure by converting zooplankton to fish biomass and providing a major forage source for cutthroat and lake trout. Aspects of cisco feeding ecology studied include characterization of the zooplankton community composition and dynamics and cisco feeding habits and prey selection.

Composition and seasonal dynamics of the zooplankton community were determined for a fifteen month period during 1981-1982. The community was dominated by a calanoid copepod, Epischura …

Proceedings -- National Wilderness Research Conference: Current Research, United States Department Of Agriculture, Forest Service

Forestry

Includes more than 70 reports of current wilderness research. Papers are organized around nine topics: wilderness resource research, including natural fire, air quality, impacts to soil and vegetation, fish and wildlife, and water; and wilderness user research related to recreational use and user characteristics, attitudes and behavior, benefits, and management concepts and tools.

Coprecipitation Of Phosphorus With Calcium Carbonate In Bear Lake, Utah - Idaho, Paul W. Birdsey Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Monitoring of Bear Lake was conducted in 1981 and 1982 to describe the current limnology and trophic state of the lake. The nutrient loadings of various parameters were measured from April, 1981 through June, 1982. The rate of coprecipitation of phosphorus was determined for different initial phosphorus concentrations by use of non-algal assays. Algal bioassays with Selenastrum capricornutum were used to determine the reduction in potential algal biomass as a result of the coprecipitation of phosphorus.

The lake exhibited chemical characteristics indicative of mesotrophy or eutrophy. Total phosphorus values averaged 11μg/1 for 1981 and 20 μg/1 for 1982. A hypolimnetic …

The Vertical Distribution And Feeding Chronology Of Larval Bear Lake Sculpin (Cottus Extensus) In Bear Lake, Utah-Idaho, D. Neverman Devroy, Wayne A. Wurtsbaugh, S. Ohlhorst

Watershed Sciences Faculty Publications

Preliminary sampling in Bear Lake, Utah/Idaho, with bottom trawls and larval fish nets indicate