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All Graduate Theses and Dissertations

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Untangling The Economic And Social Impediments To Producer Adoption Of Organic Wheat, Donya L. Ralph-Quarnstrom May 2019

Untangling The Economic And Social Impediments To Producer Adoption Of Organic Wheat, Donya L. Ralph-Quarnstrom

All Graduate Theses and Dissertations

Consumer demand for organic products has shown double-digit growth in recent years encouraging the development of a wider range of goods (Greene, 2017). Americans with an annual household income under $30,000 actively purchase organic foods at nearly the same rate as households with over $75,000 in annual incomes, 42% versus 49% (Greene et al., 2017). Previous research observed the adoption of organic farming practices on a combination of different grains, fruits and vegetables, meat, and dairy products from across the globe. However, this is the first study to examine the adoption of organic wheat in the Western U ...


Impacts Of Cattle Grazing As A Tool To Control Phragmites Australis In Wetlands On Nitrogen, Phosphorus, And Carbon, Brittany L. Duncan May 2019

Impacts Of Cattle Grazing As A Tool To Control Phragmites Australis In Wetlands On Nitrogen, Phosphorus, And Carbon, Brittany L. Duncan

All Graduate Theses and Dissertations

Phragmites australis is a plant that is causing problems in wetlands by outcompeting native plants that provide food and shelter for millions of migratory birds. Currently, managers try to control Phragmites australis by spraying herbicide, burning, and mowing, but these methods are costly, time consuming, and have low levels of success. Adding grazing as a tool to control Phragmites australis provides a cheap and low labor alternative. However, there are many concerns regarding if grazing will cause nutrient loading in our wetlands that will decrease water quality and alter beneficial functions of wetlands.

To better understand the effects of grazing ...


The Macroinvertebrate And Fish Communities Of In-Stream Beaver Ponds In Northeastern Utah, Susan Washko Dec 2018

The Macroinvertebrate And Fish Communities Of In-Stream Beaver Ponds In Northeastern Utah, Susan Washko

All Graduate Theses and Dissertations

Beavers were virtually extirpated from North America during the fur trade, but populations have since recovered. Dams built by recolonizing beaver alter stream habitat by forming deep, slow ponds within the streams. Such changes to the habitat is likely to have consequences for organisms such as macroinvertebrates and fish. The objective of this study was to identify the differences in the macroinvertebrate and trout community in beaver ponds and lotic (e.g. flowing reaches of a stream) reaches in tributaries to the Logan River in northeastern Utah. The macroinvertebrate community of beaver ponds had fewer species, fewer numbers, and lower ...


Interactions Between Fire Severity And Forest Biota In The Central Sierra Nevada: Formation And Impact Of Small-Scale Fire Refugia And The Effect Of Fire On Forest Structure Predictive Of Fisher (Pekania Pennanti) Den Habitat, Erika M. Blomdahl Dec 2018

Interactions Between Fire Severity And Forest Biota In The Central Sierra Nevada: Formation And Impact Of Small-Scale Fire Refugia And The Effect Of Fire On Forest Structure Predictive Of Fisher (Pekania Pennanti) Den Habitat, Erika M. Blomdahl

All Graduate Theses and Dissertations

Fire is a natural and essential component of forests in western North America. Fire maintains biodiversity through the creation of different habitat types, and regular fire rotations reduce the accumulation of woody fuels and thick understory plant densities that give rise to catastrophic fire. The practice of fire exclusion has altered western forests and increased the risk of widespread change under rising temperatures projected for the 21st century. To manage for the reintroduction of fire it is critical that we understand the interactions between fire and forest biota in recently fire-suppressed forests.

In Chapter 2, I studied the formation ...


Patterns Of Use Before And After A Labeling Intervention Among Collegiate Division I Athletes At A Fueling Station, Julie A. Buzzard Dec 2018

Patterns Of Use Before And After A Labeling Intervention Among Collegiate Division I Athletes At A Fueling Station, Julie A. Buzzard

All Graduate Theses and Dissertations

The Fueling Station at Utah State University was created to provide pre-workout fueling and post-workout recovery foods to the Utah State University athletes. The athletes use an online survey to mark what foods they selected after each visit to the Fueling Station.

There is a large amount of research on the lack of sports nutrition knowledge in collegiate athletes, but there is little information on the dietary intake of athletes, the education of athletes, and the education of macronutrient timing in athletes.

A food labeling system named “Gain Your Edge” food labels that targeted the education of timing was created ...


The Abiotic And Biotic Controls Of Arctic Lake Food Webs: A Multifaceted Approach To Quantifying Trophic Structure And Function, Stephen L. Klobucar Dec 2018

The Abiotic And Biotic Controls Of Arctic Lake Food Webs: A Multifaceted Approach To Quantifying Trophic Structure And Function, Stephen L. Klobucar

All Graduate Theses and Dissertations

The Arctic is warming faster than any other region of the globe. To conserve and manage many thousands of lakes across arctic landscapes, scientists need to understand historic and present conditions within these lakes to predict how the lakes, and the organisms that inhabit them, may respond to a changing climate. The goal of my research was to improve our understanding of what physical, chemical, and biological factors contribute to: 1) how lake food webs are assembled; and, 2) how these food webs may change in the future. First, I used long-term observations and lab experiments to determine how fish ...


A Needs Assessment Of Arizona Agricultural Education Equine Science Curriculum, Emily Tobler Dec 2018

A Needs Assessment Of Arizona Agricultural Education Equine Science Curriculum, Emily Tobler

All Graduate Theses and Dissertations

Like any other agricultural industry, many different career paths in the equine field are becoming more technologically advanced. To adapt to technological progress, current standards need to be integrated into school-based agricultural education courses to properly train and teach students about current industry standards. In addition to equine science curriculum development, emphasis must also be focused on providing assistance to secondary-school-based agriculture teachers so they can effectively teach industry-based equine science objectives in their programs.

The equine curriculum objectives were measured in terms of perceived importance by equine professionals and post-secondary equine educators as well as Arizona school-based agriculture teachers ...


Plant Evolutionary Response To Climate Change: Detecting Adaptation Across Experimental And Natural Precipitation Gradients, Jacqueline J. Peña Dec 2018

Plant Evolutionary Response To Climate Change: Detecting Adaptation Across Experimental And Natural Precipitation Gradients, Jacqueline J. Peña

All Graduate Theses and Dissertations

Global climate change is a real-time problem that presents threats to many species. Climate change can alter ecosystems and may lead to species extinction. Species can respond to climate change by moving to a better environment or adapting. Therefore, it is necessary to rely on several approaches and perspectives to anticipate ecological impacts of climate change. A common strategy uses models to understand how populations respond to different climate scenarios. Ecological models have helped usunderstand population persistence, but they often ignore how populations adapt to environmental stress. Adaptive evolution has been ignored because it was assumed that evolution was too ...


Identification Of Sperm Chromatin Proteins As Candidate Markers Of Stallion Fertility, Chelsea C. Ketchum Dec 2018

Identification Of Sperm Chromatin Proteins As Candidate Markers Of Stallion Fertility, Chelsea C. Ketchum

All Graduate Theses and Dissertations

During spermatogenesis, histones are largely replaced by transition proteins and protamines in normal stallions. Incomplete nucleoprotein exchange results in the abnormal retention of histones and transition proteins, which is an indicator of poor sperm quality. Equine nucleoprotein exchange has not previously been investigated in detail, so that equine sperm chromatin quality problems, which are often responsible for poor breeding performance of stallions, are not well understood. In order to characterize chromatin remodeling events in stallion spermatogenesis and to identify proteins indicative of sperm chromatin defects, such as excessive amounts of histones, we identified antibodies that recognize equine testis-specific proteins of ...


Assessing The Ecological Implications Of The Altered Flow And Sediment Regimes Of The Rio Grande Along The West Texas-Mexico Border, Demitra E. Blythe Dec 2018

Assessing The Ecological Implications Of The Altered Flow And Sediment Regimes Of The Rio Grande Along The West Texas-Mexico Border, Demitra E. Blythe

All Graduate Theses and Dissertations

Large, exotic (those whose headwaters are in distant places) rivers are some of the most unique and diverse ecosystems on earth. Because they often flow through a multitude of biomes and climates, their waters are a vital resource not only for the organisms that inhabit these rivers, but for human societies as well. Thus, large rivers, like the Rio Grande, that flow through arid and agricultural regions are highly regulated and diverted. Regulation and dewatering upset a river’s natural flow regime (e.g., magnitude, duration, timing of large flood events), subsequently impacting the river’s ability to transport its ...


Geospatial Modeling Of Land Cover Change In The Chocó-Darien Global Ecoregion Of South America: Assessing Proximate Causes And Underlying Drivers Of Deforestation And Reforestation, José Camilo Fagua Dec 2018

Geospatial Modeling Of Land Cover Change In The Chocó-Darien Global Ecoregion Of South America: Assessing Proximate Causes And Underlying Drivers Of Deforestation And Reforestation, José Camilo Fagua

All Graduate Theses and Dissertations

The Chocó-Darien Global Ecoregion (CGE) in South America is one of 25 global biodiversity hotspots prioritized for conservation. I performed the first land-use and land-cover (LULC) change analysis for the entire CGE in this dissertation. There were three main objectives: 1) Select the best available imagery to build annual land-use and land-cover maps from 2001 to 2015 across the CGE. 2) Model LULC across the CGE to assess forest change trends from 2002 to 2015 and identify the effect of proximate causes of deforestation and reforestation. 3) Estimate the effects of underlying drivers on deforestation and reforestation across the CGE ...


Comparison Of Methods For Extracting Lactobacillus Wasatchensis Dna From Broth Media, Milk, And Cheese For Subsequent Pcr-Based Analyses, Tyler Allen Dec 2018

Comparison Of Methods For Extracting Lactobacillus Wasatchensis Dna From Broth Media, Milk, And Cheese For Subsequent Pcr-Based Analyses, Tyler Allen

All Graduate Theses and Dissertations

The Western Dairy Center at Utah State University funded this project as part of its BUILD Dairy program with support from the dairy farmers of Idaho, to investigate the problem of splits that form in cheese during storage. The bacteria, Lactobacillus wasatchensis had previously been identified as a cause of unwanted gas production in cheese and the defects then make the cheese unsuitable for cutting into slices.

The project team proposed a two-year, $150,912 project to investigate methods for determining the presence of this bacterium in cheese by extracting DNA from the cheese and looking for DNA that was ...


Co-Digestion Of Cattle Manure And Cheese Whey For Biogas Production And Characterization Of Biomass Effluent, Dillon Fallon Dec 2018

Co-Digestion Of Cattle Manure And Cheese Whey For Biogas Production And Characterization Of Biomass Effluent, Dillon Fallon

All Graduate Theses and Dissertations

The Western Dairy Center at Utah State University had recognized through traiing of cheesemaking that a challenge that can exist for farmstead and artisan cheese manufacturing operations is disposal or utilization of the whey that is produced when milk is converted into cheese. Land application of whey is limited and can cause odor problems which would be detrimental to a cheesemaking operation located at the rual-urban interface.

The project provided information in support of a research grant from the Western Sustainable Agribulture Research and Education program that was investigating economics and feasiblity of using anaerobic digestion for treatment of whey ...


Evaluation Of Antioxidant Properties Of Native Utah Berries And Their Potential For Use In Meats, Xiaoxi Wang Dec 2018

Evaluation Of Antioxidant Properties Of Native Utah Berries And Their Potential For Use In Meats, Xiaoxi Wang

All Graduate Theses and Dissertations

In industry, antioxidants are added to prevent changes that affect quality due to oxidation, such as the development of off flavors, unacceptable odors and discoloration. New resources that are familiar to consumers and may work as antioxidants should be studied.

The changes in antioxidant activity were determined for four freeze-dried native wild berry powder species in Utah, including skunkbush (Rhus trilobata), chokecherry (Prunus virginiana), river hawthorn (Crataegus douglasii) and silver buffaloberry (Shepherdia argentea), during cold storage (-20 °C) for 6 months. The total antioxidant activity was stable in most of the berry powders during the six months of frozen storage ...


Development And Application Of A Reverse Genetics System For Zika Virus, Jordan C. Frank Dec 2018

Development And Application Of A Reverse Genetics System For Zika Virus, Jordan C. Frank

All Graduate Theses and Dissertations

Zika virus (ZIKV) has emerged in many regions of the world, with infection outcomes spanning from no apparent illness to crippling nervous system disease. ZIKV and its close relatives, West Nile virus, Japanese encephalitis virus, dengue virus, and yellow fever virus are primarily transmitted by mosquitoes. Three ZIKVs were selected: MR-766 (Uganda, 1947), P6-740 (Malaysia, 1966), and PRVABC-59 (Puerto Rico, 2015), whose place of origin and time of isolation differ substantially. Stable, complementary DNA (cDNA) copies of the three ZIKV RNA genomes were cloned to examine the significance of viral and host genetic variations in directing ZIKV infection outcomes. Using ...


Landscape Planning For Climate Change Resilience In The Southern Rockies, Jeffrey D. Haight Dec 2018

Landscape Planning For Climate Change Resilience In The Southern Rockies, Jeffrey D. Haight

All Graduate Theses and Dissertations

The unique species, ecosystems and landscapes of the Western United States are experiencing unprecedented pressures from climate change, creating new challenges for conservation. As temperatures rise and patterns of precipitation shift, plant and wildlife species have been shifting their ranges to new areas in search of more suitable climates, building groupings of species that are historically unfamiliar. These climate -driven migrations place an additional burden on species that are already threatened from habitat loss and other human-related activities. The impacts of climate change are of particular concern in landscapes that have long been conserved and managed based on the ecological ...


Sociodemographic And Climatic Factors Shaping The Development Of Drought Policies In Major U.S. Cities, Riana S. Gayle Dec 2018

Sociodemographic And Climatic Factors Shaping The Development Of Drought Policies In Major U.S. Cities, Riana S. Gayle

All Graduate Theses and Dissertations

In most parts of the world, drought is an inevitable and natural occurrence. However, as the climate continues to warm, and populations grow and expand, the negative impacts of this extreme weather event are predicted to become more pronounced. This leads many communities and stakeholders to question what is being done to prepare society for widespread drought? The following research determines different social and atmospheric characteristics that affect a city’s likelihood of having a drought policy in place.To do this, a thorough search was conducted at the city level to determine where drought policies are currently located in ...


Efficacy Of Translocation As A Management Tool For Urban Mule Deer In Utah, Channing R. Howard Dec 2018

Efficacy Of Translocation As A Management Tool For Urban Mule Deer In Utah, Channing R. Howard

All Graduate Theses and Dissertations

An increase in urbanization in the United States has led to an increase in human-wildlife interactions with deer (Odocoileus spp.) which have been able to adapt and thrive in these urban environments. In Utah, urbanization has occurred along the Wasatch Front which was once traditional mule deer (Odocoileus hemionus) winter range habitat. This urban expansion coupled with an increasing use of these urban areas by mule deer, have led to increasing conflicts with deer. Overabundant urban deer have led to increased concerns over safety from deer-vehicle collisions, and damage to personal property including gardens and landscaping. Lethal methods of urban ...


A Simple Metabolic Switch May Activate Apomixis In Arabidopsis Thaliana, David Alan Sherwood Dec 2018

A Simple Metabolic Switch May Activate Apomixis In Arabidopsis Thaliana, David Alan Sherwood

All Graduate Theses and Dissertations

Apomixis, asexual or clonal seed production in plants, can decrease the cost of producing hybrid seed and enable currently open pollinated crops to be converted to more vigorous and higher yielding hybrids that can reproduce themselves through their own seed. Sexual reproduction may be triggered by a programmed stress signaling event that occurs in both the meiocyte, just prior to meiosis, and later in the egg just prior to embryo sac maturation. The prevention of stress signaling and the activation of a pro-growth signal prior to meiosis triggered apomeiosis, the first half of apomixis. The same approach was used prior ...


Influence Of Environmental Variables On Survival Rates Of Pronghorn (Antilocapra Americana) Neonates Across Idaho, Brett R. Panting Dec 2018

Influence Of Environmental Variables On Survival Rates Of Pronghorn (Antilocapra Americana) Neonates Across Idaho, Brett R. Panting

All Graduate Theses and Dissertations

This study was completed to better understand pronghorn antelope (Antilocapra americana) populations found throughout Idaho. Antelope were studied in three separate and distinct study areas. The Big Desert, Camas Prairie, and Little Lost and Pahsimeroi valleys were all selected as study sites. Idaho Department of Fish and Game (IDFG) is concerned with current pronghorn populations found throughout Idaho. Pronghorn are a valued big game species found in Idaho. Increasing pronghorn populations in Idaho is a focus of IDFG.

We captured and VHF-collared pronghorn fawns found in our three study areas. Fawns were monitored daily with telemetry equipment for survival. Field ...


Organic Matter Sources, Composition, And Quality In Rivers And Experimental Streams, Julia E. Kelso Dec 2018

Organic Matter Sources, Composition, And Quality In Rivers And Experimental Streams, Julia E. Kelso

All Graduate Theses and Dissertations

Organic matter (OM) is often considered the “currency” for ecosystem processes, such as respiration and primary production. OM in aquatic ecosystems is derived from multiple sources, and is a complex mixture of thousands of different chemical constituents. Therefore, it is difficult to identify all the sources of OM that enter and exit aquatic ecosystems. As humans develop undisturbed land, the rate at which terrestrial OM (e.g.soil and plants) and associated nutrients (e.g.nitrogen) enters rivers has increased. Increased nutrients may lead to increased primary production from aquatic plants and algae, potentially causing eutrophication and harmful algal blooms ...


Interactions Between Biochar And Compost In Organic Winter Wheat Production And Soil Quality Under Dryland Conditions, Phearen Kit Miller Dec 2018

Interactions Between Biochar And Compost In Organic Winter Wheat Production And Soil Quality Under Dryland Conditions, Phearen Kit Miller

All Graduate Theses and Dissertations

Organic wheat grown under dryland conditions encounters challenges such as limited nutrients and water. Maintaining organic wheat production requires solutions to these problems in order to retain economic sustainability for the farmers.

Research on biochar and compost have been conducted globally. Despite well known benefits of compost on soil and crop production, few organic farmers apply compost to their fields. Research on biochar is still new. Biochar is charcoal created from pyrolyzing agricultural material under conditions of low oxygen and high heat. Many studies claim that biochar is a valuable soil amendment for improving organic production and reducing environmental pollution ...


An Evaluation Of Bull Trout Movement Dynamics In The Walla Walla River, Courtney Newlon Dec 2018

An Evaluation Of Bull Trout Movement Dynamics In The Walla Walla River, Courtney Newlon

All Graduate Theses and Dissertations

Bull trout are a fish species listed as threatened under the Endangered Species Act.Historically, they ranged from Northern California at the southernmost extent, into Canada at the northern most extent, and east into Nevada and Montana. Bull trout are highly migratory and require large, unfragmented habitats to persist and are thus highly susceptible to human induced land-use practices. The goal of my thesis was to obtain a better understanding of bull trout movement patterns in the Walla Walla River, Washington using complimentary techniques; Passive Integrated Transponder (PIT)technology and otolith microchemistry. PIT tags can be injected into a fish ...


The Nesting Ecology Of Woodpeckers In The Eastern Cascades And Their Interactions With Nest Competitors And Predators, Samuel D. Cowell Dec 2018

The Nesting Ecology Of Woodpeckers In The Eastern Cascades And Their Interactions With Nest Competitors And Predators, Samuel D. Cowell

All Graduate Theses and Dissertations

Woodpeckers create nesting cavities for other birds and animals in forests. This creates dynamic interactions between both woodpeckers and these other animals. Using video cameras, we documented direct behavioral interactions between nesting woodpeckers and other animals in the Eastern Washington Cascades during the 2015 and 2016 breeding seasons. Additionally, we offered 937 students in a General Biology laboratory course to participate in this original research opportunity and described and the impact the experience had on the participants as well as the researchers.

In 2015, Western Blubebirds took over two active Black-backed Woodpecker nests by physically attacking the woodpeckers. In 2016 ...


Blue And Red Light Effects On Stomatal Oscillations, Trevor R. Ballard Dec 2018

Blue And Red Light Effects On Stomatal Oscillations, Trevor R. Ballard

All Graduate Theses and Dissertations

Plants absorb CO2 through pores in their leaves called stomata, which are known to open and close in response to myriad environmental and physiological triggers. We demonstrate that blue light inhibits stomatal aperture oscillations in both the guard cells and surrounding tissue layers, whereas these oscillations continue under the influence of red light. This observation of blue light behavior agrees with recent research and suggests another physiological pathway for oscillations.


Comparative Pollination Efficacies Of Bees On Raspberry And The Management Of Osmia Lignaria For Late Blooming Crops, Corey J. Andrikopoulos Aug 2018

Comparative Pollination Efficacies Of Bees On Raspberry And The Management Of Osmia Lignaria For Late Blooming Crops, Corey J. Andrikopoulos

All Graduate Theses and Dissertations

Unlike other rosaceous fruit crops such as apple and cherry, commercial raspberry cultivars are largely self-fertile and can set fruit in the absence of pollinators. However, their floral morphology often prevents complete self-pollaintion. Incomplete pollination yields unmarketable small or crumbly fruits. Insect visitation is therefore essential to maximizing raspberry yield. Honey bees are typically used to pollinate commercial raspberry; however, escalating prices for hive rentals coupled with increasing acreage encourage evaluation of other manageable pollinators. Bumble bees (Bombus spp.) and several mason bees (Osmia spp.) are promising raspberry pollinators. Five bee species were evaluated and compared for their single-visit pollination ...


Phenotypic Association Between Lactose And Other Milk Components In Western Us Dairy Herds And Japan, Takuji Asami Aug 2018

Phenotypic Association Between Lactose And Other Milk Components In Western Us Dairy Herds And Japan, Takuji Asami

All Graduate Theses and Dissertations

Lactose in milk has relatively low variation regardless of season, breed, or country. The study of lactose concentration and correlation among other milk components is limited. Furthermore, dairy farmers have limited access to the lactose data and are not familiar with it. This study was conducted to: 1) investigate the phenotypic correlation between lactose and other milk components; and 2) determine the importance of lactose for dairy herds.

Monthly DHIA records from Utah (DHIA), Dairy Herd Performance Test (DHTP) records from Ibaraki, Japan, and California herd average data (CHAD) covering 27 states were used to analyze the relationships between milk ...


Utilizing Legumes To Improve Production And Nutritive Value Of Intermountain West Pastures, Jacob T. Briscoe Aug 2018

Utilizing Legumes To Improve Production And Nutritive Value Of Intermountain West Pastures, Jacob T. Briscoe

All Graduate Theses and Dissertations

Pastures in the Intermountain Western United States mainly consist of cool-season grasses which lack production without supplemental nitrogen. Legumes provide nitrogen at reduced cost compared to nitrogen fertilizer. There is a need for proven methods of inter-seeding legumes into existing cool-season grass pastures as well as knowledge of how animals prefer legumes to grasses and how the nutritive value of forages change throughout the growing season. This research provides a resource for effective integration of legumes into pastures of the Intermountain West. Alfalfa, birdsfoot trefoil, and cicer milkvetch were inter-seeded into existing cool-season grass pastures following pretreatments of light tillage ...


Incentivizing Fruit, Vegetable, And Physical Activity Level Change: Expansion And Evaluation Of The Fit Game Program For Healthy Behavior Change In Elementary Schools, Damon L. Joyner Aug 2018

Incentivizing Fruit, Vegetable, And Physical Activity Level Change: Expansion And Evaluation Of The Fit Game Program For Healthy Behavior Change In Elementary Schools, Damon L. Joyner

All Graduate Theses and Dissertations

Researchers in the Nutrition, Dietetics and Food Science department and Psychology department sought to improve healthy behaviors in elementary schools such as fruit and vegetable consumption (FV) and daily physical activity (PA). We chose to use a healthy behavior program called the “FIT Game” that has successfully increased FV consumption among elementary-aged children over short periods of time. Our aim was to improve the program by lowering operating costs, adjusting its materials to target PA and see if it could maintain healthy eating improvements over a longer period of time. Our series of research shows encouraging results: short term improvements ...


Using Anthropogenic Risks To Inform Salmonid Conservation At The Landscape Scale, Andrew W. Witt Aug 2018

Using Anthropogenic Risks To Inform Salmonid Conservation At The Landscape Scale, Andrew W. Witt

All Graduate Theses and Dissertations

The expansion and industrialization of humanity has caused many unforeseen consequences to the natural world. Due to the importance of freshwater for people, rivers have been particularly altered to meet human needs, often at the expense of the natural world. Supplying water for farms, industries, and cities has reshaped the natural state of rivers by altering river paths, chemistry, and species compositions. These changes have harmed many species that prospered before widespread human alterations, including the native trout and salmon of western North America. As human populations continue to grow, new threats will surface for rivers, and the trout and ...