Aquaculture and Fisheries Commons^™

The Impacts Of A Quagga And Zebra Mussel Infestation, Casey Silva

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Invasive species issues have been on the rise in the United States for decades. These organisms can disrupt the natural flow of an ecosystem and overtake native species, altering an environment as a whole. The introduction of the zebra mussel (Dreissena polymorpha) in 1988, followed by the quagga mussel (Dreissena rostriformis) in 1989 is arguably the most prolific aquatic infestation the nation is currently up against (Hoddle, 2022). Beginning in the Great Lakes, both quagga and zebra mussels quickly spread their infestations through the Midwest and the East coast. The potential invasion of these species across …

Evaluating The Effect Of The Removal Of Non-Native Trout In Two High Elevation Tributary Streams In The Intermountain West, Clint Brunson

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Native fish species such as Bonneville Cutthroat Trout (BCT) require cold, clear, well-connected streams for spawning and rearing as well as access to complimentary habitats. Increasing river temperatures and lower water flows may have allowed non-native Brown Trout (BNT) to migrate into higher elevation pristine streams. Additionally, anthropogenic actions such as stocking non-native Brown and Brook (BKT) and Rainbow Trout (RBT) for angling opportunities impact BCT. Invasion of these tributaries by non-native species may reduce or eliminate cutthroat trout by predation, competition, displacement, genetic suppression, and exclusion. A seven-fold increase in BNT numbers of 50 to 350 from 2017 to …

A Comparison Of Five Statistical Methods For Predicting Stream Temperature Across Stream Networks, Maike F. Holthuijzen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The health of freshwater aquatic systems, particularly stream networks, is mainly influenced by water temperature, which controls biological processes and influences species distributions and aquatic biodiversity. Thermal regimes of rivers are likely to change in the future, due to climate change and other anthropogenic impacts, and our ability to predict stream temperatures will be critical in understanding distribution shifts of aquatic biota. Spatial statistical network models take into account spatial relationships but have drawbacks, including high computation times and data pre-processing requirements. Machine learning techniques and generalized additive models (GAM) are promising alternatives to the SSN model. Two machine learning …

From Disaster To Sustainability: The Story Of The Pacific Groundfish, Matthew Richards

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This paper reviews the circumstances that led to the collapse of the Pacific groundfish fishery and the steps that fishery managers took to curb over-harvesting and bring the fishery back to sustainability. Fishery managers utilized various management tools such as a vessel buyback program, regulatory mechanisms, and market strategies to improve the available data on the fishery, improve safety for fishermen, and reduce harvest rates and overcapitalization. By employing a diverse range of measures, managers developed a system by with they successfully balanced conservation objectives and minimized adverse impacts to fishing communities. Overcapitalization and overharvest continue to degrade the health …

Evaluating Habitat-Based Niche Requirements And Potential Recruitment Bottlenecks For Imperiled Bluehead Sucker (Catostomus Discobolus), Bryan C. Maloney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes to rivers that alter physical and thermal habitat may cause fish population abundance to decline, due to fewer individuals maturing and entering the adult population. The Weber River has become highly degraded with many dams and diversions altering fish habitat, river volume, velocity, and temperature, and limiting movement between reaches. Bluehead suckers (Catostomus discobolus) occupy only 47% of their historical range and the genetically-distinct Weber River (northern UT) population is declining and contains few young, juvenile fish. My objectives were to determine whether spawning and rearing habitat available in the Weber River may be limiting bluehead sucker …

Colorado River Cutthroat Trout Habitat Resistance And Resilience To Climate Change, Kate H. Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Government agencies and private organizations spend large amounts of public money attempting to return ecosystems to a more natural state, which have often been harmed or even destroyed as a result of modern development. Colorado River cutthroat trout, Oncorhyncus clarki pleuriticus, are a subspecies of cutthroat trout. Cutthroat trout live in the Rocky Mountains of the western United States. The population of this particular subspecies has been severely reduced by human actions, and currently only 12% of its historic populations still exist. To improve the condition of cutthroat trout, fisheries professionals and biologists are working to restore natural populations. …

Comparison Of Topographic Surveying Techniques In Streams, Sara G. Bangen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Bonneville Power Administration (BPA) Fish and Wildlife Program (FWP) mitigates impacts, including mortality, from hydroelectric dams in the Columbia River Basin for ESA-listed salmon and steelhead populations and other species of special concern. Given the extensive economic resources invested in mitigation and the incredible diversity of in-stream habitat across the Columbia River basin, questions have arisen about which sampling strategies are most tractable across the entire Columbia River Watershed, but also produce datasets that allow researchers to answer meaningful questions about salmonid populations and trends in habitat. In response to these issues, the NOAA Integrated Status and Effectiveness Monitoring …

Genetic Status Of Isolated Populations Of Colorado River Cutthroat Trout (Oncorhynchus Clarkii Pleuriticus) In The North Fork Little Snake River Drainage, Wyoming, Rachel Van Horne

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the last century native cutthroat trout populations have declined in the western United States. Habitat fragmentation is one of the main causes for this decline. Human actions such as the construction of roads, weirs, dams, and water diversions intersect streams and prevent the natural movement of fish. In many cases native cutthroat trout are now confined to headwater streams above human-created barriers. These barriers not only fragment the populations but also increase the risk of individual population extinction.

This study established a baseline genetic structure for nine isolated populations of Colorado River cutthroat trout in the North Fork Little …

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …

The Effect Of Irrigation Diversions On The Mountain Whitefish (Prosopium Williamsoni) Population In The Big Lost River, Patrick Allen Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Management agencies documented a decline in the mountain whitefish (Prosopium williamsoni) population on the Big Lost River, and unscreened diversions were recognized as a potential factor for this decline. Research suggests the Big Lost River mountain whitefish population is genetically unique, and it has been petitioned for protection under the Endangered Species Act. In 2007, a basin-wide synopsis of diversions was conducted to describe relative entrainment and identify diversions that entrained the most mountain whitefish. This larger scaled synopsis facilitated a more precise assessment of entrainment by a subset of diversions in 2008. In 2008, the volume that …

Maintaining Population Persistence In The Face Of An Extremely Altered Hydrograph: Implications For Three Sensitive Fishes In A Tributary Of The Green River, Utah, Jared L. Bottcher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ability of an organism to disperse to suitable habitats, especially in modified and fragmented systems, determines individual fitness and overall population viability. The bluehead sucker (Catostomus discobolus), flannelmouth sucker (Catostomus latipinnis), and roundtail chub (Gila robusta) are three species native to the upper Colorado River Basin that now occupy only 50% of their historic range. Despite these distributional declines, populations of all three species are present in the San Rafael River, a highly regulated tributary of the Green River, Utah, providing an opportunity for research. Our goal was to determine the timing and …

Movement Patterns And Multi-Scale Factors That Influence Exotic Brook Trout And Endemic Bonneville Cutthroat Trout Distribution And Abundance In The Mill Creek Drainage, Utah, Benjamin Keith Nadolski

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Introduced brook trout (Salvelinus fontinalis) are implicated as a primary factor leading to the decline in distribution and abundance of native cutthroat trout (Oncorhynchus clarkii). However, not all introductions are successful, suggesting local conditions influence the success of invasions. Therefore, I sought to determine the multi-scale factor(s) that influence brook trouts’ invasion success of native Bonneville cutthroat trout (Oncorhynchus clarkii utah) habitats in Mill Creek, Utah. I conducted patch occupancy surveys to determine watershed-scale brook trout and cutthroat trout distribution. I also determined the relative abundance of brook trout and cutthroat trout at the …

Kokanee Fry Recruitment And Early Life History In The Lake Tahoe Basin, Christine K. Gemperle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lake Tahoe kokanee salmon have experienced decreasing mean adult size and fluctuating populations since 1970. We proposed to determine whether fish production was limited by spawning and incubation processes in Taylor Creek, or by growth constraints, or by mortality in the lake by studying egg-to-fry survival rates and early life history. Estimated egg-to-fry survival was 15. 9% for the 1994 brood year and 1.5% for the 1995 brood year. Egg-to-adult survival was 3.5% for the 1991 brood year and 5.9% for the 1992 brood year. Of the 35 possible survival scenarios, egg-to-fry survival was 7.5-20% and fry-to-adult survival (inlake phase) …

Effects Of Uv-B Radiation On Egg And Larval Golden Shiner (Notemigonus Crysoleucas) In Castle Lake, California, Jai-Ku Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied effects of UV-B radiation on egg and larval golden shiner (Notemigonus crysoleucas) in Castle Lake, California, USA. To compare egg hatching and survival of larval golden shiner, I exposed eggs and larval fish to three different UV-B treatments, low UV-B (4% UV-B), high UV-B (92% UV-B), and ambient (100% UV-B). The egg experiment was conducted in lake and pond water, whereas proto- and mesolarval stage experiments were conducted in lake water only.

High and ambient UV-B radiation affected the hatching rate of golden shiner eggs. The mean hatching rate was 13% lower in high UV-B, and …

Evaluation Of Translocation Criteria For Trumpeter Swans Reintroduced To Northern Utah: Habitat Quality And Interactions With Tundra Swans, Katharina A. M. Engelhardt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fifty-seven Trumpeter swans (Cygnus buccinator) were translocated to the Bear River Migratory Bird Refuge and the Bear River Club Company in northern Utah. The purpose of this effort was to encourage dispersal of the Rocky Mountain population of Trumpeter swans during the winter, and to reestablish a migratory route to southern wintering grounds. I assessed the success of the translocation by evaluating 13 translocation criteria proposed in the literature. In this study I addressed two of these criteria in detail by evaluating habitat quality at the translocation sites and by analyzing potential competitive interactions with Tundra swans ( …

Assessment Of Kokanee Salmon, Oncorhynchus Nerka, Genetic Stocks In Flaming Gorge Reservoir, Utah-Wyoming, Michael F. Canning

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated the relative abundance, spatial distributions, return to the creel, and growth rates of two genetic stocks of kokanee salmon, Oncorhynchus nerka, in Flaming Gorge Reservoir, Utah-Wyoming. The two genetic stocks consist of fish from the two major spawning populations of kokanee in the reservoir. One population, Shore Spawners, spawns along the eastern shoreline of the Open Hills area of the reservoir. The other population, Sheep Creek, spawns in Sheep Creek, a tributary located in the Canyon area of the reservoir.

Mitochondrial DNA of kokanee from each population was analyzed to determine haplotype differences between stocks. These haplotype …

Physical Factors Influencing Survival To Emergence And Time Of Emergence Of Shoreslope-Spawned Kokanee Salmon In Flaming Gorge Reservoir, Utah-Wyoming, Randall J. Jeric

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I used incubation baskets containing viable eggs and spawning substrate to estimate the survival to emergence and time of emergence of kokanee salmon Oncorhynchus nerka at depths to 20 m in Flaming Gorge Reservoir, Utah-Wyoming. Traps on the incubation baskets captured fry emerging from a known quantity of eggs. Water drawn into a syringe from an intragravel pipe buried near each incubation basket was used to determine intragravel dissolved oxygen concentrations throughout the intragravel period. Water from control baskets without eggs did not have significantly greater dissolved oxygen concentrations than adjacent water. A jar associated with each incubation basket collected …

Habitat Selection And Movement Of A Stream-Resident Salmonid In A Regulated River And Tests Of Four Bioenergetic Optimization Models, Mark D. Bowen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A bioenergetics model was constructed for stream-resident drift-feeding salmonids. Model predictions of surplus power (energy available per unit time for growth and reproduction) were not statistically distinguishable from observations of surplus power in three laboratory studies. Of 40 experimental trials in these three studies, the model correctly predicted surplus power in 39 cases (p < 0.05).

I collected observations of rainbow trout (Oncorhynchus mykiss) focal velocity and physical habitat availability in the Green River of northeastern Utah, USA (1988-1990). In the winter of 1988, Flaming Gorge Dam generated hydropower and delivered an lJDStable discharge regime with a higher mean discharge …

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 …

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 …

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 …

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 …

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 …

Investigation Of Selected Aspects Of Kokanee (Onchorhynchus Nerka) Ecology In Porcupine Reservoir, Utah, With Management Implications, Paul Joel Janssen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several aspects of kokanee (Onchorhynchus nerka) ecology were studied in the fluctuating, 80ha Porcupine Reservoir, Utah in order to determine optimum management strategies. In 1981, escapement was enumerated and estimates of egg deposition were made. An estimate of the resulting fry recruitment was also attempted and was successful up to the arrival of spring runoff. In 1982, escapement was enumerated and estimates of egg deposition were made, with subsequent estimates of egg deposition and percent survival to the advanced eyed stage. Age and growth rates were determined and survival rates estimated.

Escapement for 1981 and 1982 was 5,463 …

Cougar Predation And Ecological Energetics In Southern Utah, Bruce Bennet Ackerman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diet of cougars (Felis concolor) was studied from December 1978 to August 1981, on a 4500 km2 study area near Escalante, Utah. Prey eaten was determined from analysis of 112 animals consumed as prey, and from 239 cougar scats. Mule deer (Odocoileus hemionus) were the major prey item, comprising 81% of biomass consumed. Lagomorphs, large rodents, and smaller predators were also important components. Cattle comprised <1% of the diet, although commonly grazed on the cougar's summer range. Adult male and juvenile (<1yr) mule deer were killed more often than expected, in fall (P<0.10) and in winter (P<0.005). Cougars were a major cause of mortality of adult deer (41% of all adult female deaths, 35% of male), but only 6% of mortality of juveniles. Selection of prey seemed to be a function of prey vulnerability, rather than one of active choice by the predator.

Motion-sensitive radio-transmitters were placed on 15 cougars, from 3 months to 7-9 years of age. Three parameters of the radio signal were used to determine activity levels during 6843 …

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …