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Full-Text Articles in Physical Sciences and Mathematics

The Irrigation Efficiency Trap: Rational Farm-Scale Decisions Can Lead To Poor Hydrologic Outcomes At The Basin Scale, Christina N. Morrisett, Robert W. Van Kirk, London O. Bernier, Andrea L. Holt, Chloe B. Perel, Sarah E. Null Aug 2023

The Irrigation Efficiency Trap: Rational Farm-Scale Decisions Can Lead To Poor Hydrologic Outcomes At The Basin Scale, Christina N. Morrisett, Robert W. Van Kirk, London O. Bernier, Andrea L. Holt, Chloe B. Perel, Sarah E. Null

Watershed Sciences Faculty Publications

Agricultural irrigation practices have changed through time as technology has enabled more efficient conveyance and application. In some agricultural regions, irrigation can contribute to incidental aquifer recharge important for groundwater return flows to streams. The Henrys Fork Snake River, Idaho (United States) overlies a portion of the Eastern Snake Plain Aquifer, where irrigated agriculture has occurred for over a century. Using irrigator interviews, aerial and satellite imagery, and statistical streamflow analysis, we document the impact of farm-scale decisions on basin-scale hydrology. Motivated to improve economic efficiency, irrigators began converting from surface to center-pivot sprinkler irrigation in the 1950s, with rapid …


From Mountain Streams To Urban Rivers: An Assessment Of Microplastic Sources And Characteristics, Macy Gustavus May 2023

From Mountain Streams To Urban Rivers: An Assessment Of Microplastic Sources And Characteristics, Macy Gustavus

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plastic products are produced and discarded at an alarming rate. Bottles, bags, toys, and clothing break down into tiny plastic pieces called microplastics, ranging in size from an eraser on the top of a pencil to smaller in size than a red blood cell. Microplastics are becoming so common in the environment that they travel in the atmosphere, rivers, and ocean currents in ways that are similar to other types of Earth Systems Cycles (i.e., the water cycle). In this study, we explored microplastic sources and sinks in a freshwater river system and how seasonal changes in discharge affect how …


Beavers Alter Stream Macroinvertebrate Communities In Northeastern Utah, Susan E. Washko, Brett B. Roper, Trisha Brooke Atwood Dec 2019

Beavers Alter Stream Macroinvertebrate Communities In Northeastern Utah, Susan E. Washko, Brett B. Roper, Trisha Brooke Atwood

Watershed Sciences Faculty Publications

  1. Understanding changes in macroinvertebrate communities is important because they play a large role in stream ecosystem functioning, and they are an important food resource for fish. Beaver‐induced changes to stream morphology could alter macroinvertebrate communities, which in turn could affect food webs and ecosystem function. However, studies investigating the effects of North American beaver activities on macroinvertebrates are rare in the inter‐mountain west, an area with high potential for beaver‐assisted restoration.
  2. The aim of this study was to quantify differences in the macroinvertebrate community between unaltered segments of streams and within beaver ponds in north‐eastern Utah, U.S.A. We assessed macroinvertebrate …


Natural And Managed Watersheds Show Similar Responses To Recent Climate Change, Darren L. Ficklin, John T. Abatzoglou, Scott M. Robeson, Sarah E. Null, Jason H. Knouft Aug 2018

Natural And Managed Watersheds Show Similar Responses To Recent Climate Change, Darren L. Ficklin, John T. Abatzoglou, Scott M. Robeson, Sarah E. Null, Jason H. Knouft

Watershed Sciences Faculty Publications

Changes in climate are driving an intensification of the hydrologic cycle and leading to alterations of natural streamflow regimes. Human disturbances such as dams, land-cover change, and water diversions are thought to obscure climate signals in hydrologic systems. As a result, most studies of changing hydroclimatic conditions are limited to areas with natural streamflow. Here, we compare trends in observed streamflow from natural and human-modified watersheds in the United States and Canada for the 1981–2015 water years to evaluate whether comparable responses to climate change are present in both systems. We find that patterns and magnitudes of trends in median …


Calibration Parameter Selection And Watershed Hydrology Model Evaluation In Time And Frequency Domains, Karthik Kumarasamy, Patrick Belmont May 2018

Calibration Parameter Selection And Watershed Hydrology Model Evaluation In Time And Frequency Domains, Karthik Kumarasamy, Patrick Belmont

Watershed Sciences Faculty Publications

Watershed scale models simulating hydrological and water quality processes have advanced rapidly in sophistication, process representation, flexibility in model structure, and input data. With calibration being an inevitable step prior to any model application, there is need for a simple procedure to assess whether or not a parameter should be adjusted for calibration. We provide a rationale for a hierarchical selection of parameters to adjust during calibration and recommend that modelers progress from parameters that are most uncertain to parameters that are least uncertain, namely starting with pure calibration parameters, followed by derived parameters, and finally measured parameters. We show …


The Relationship Between Measures Of Annual Livestock Disturbance In Western Riparian Areas And Stream Conditions Important To Trout, Salmon, And Char, Lindsey M. Goss, Brett B. Roper Apr 2018

The Relationship Between Measures Of Annual Livestock Disturbance In Western Riparian Areas And Stream Conditions Important To Trout, Salmon, And Char, Lindsey M. Goss, Brett B. Roper

Watershed Sciences Faculty Publications

Managing livestock disturbance in riparian zones in a manner that provides economic returns to ranchers while protecting streams is an important aspect of rangeland management on public lands in the western United States. Attempts to balance economic and ecologic outcomes have been made more difficult due to the presence of several salmonid species that are protected under the Endangered Species Act. One approach to proper management of livestock use near streams has been to define the allowable limits of disturbance using 2 metrics, streambank alteration and stubble height. We evaluated 153 stream reaches within the Interior Columbia Basin to determine …


A Study Of The Spawning Ecology And Early Life History Survival Of Bonneville Cutthroat Trout, Phaedra E. Budy, Sarah Wood, Brett B. Roper May 2012

A Study Of The Spawning Ecology And Early Life History Survival Of Bonneville Cutthroat Trout, Phaedra E. Budy, Sarah Wood, Brett B. Roper

Watershed Sciences Faculty Publications

We completed a large-scale field experiment in four tributaries of the Logan River, Utah, where the largest metapopulation of imperiled Bonneville cutthroat trout Oncorhynchus clarkii utah persists. We documented the spatial and temporal distributions of spawners, quantified substrate use versus substrate availability, and evaluated differences in hatch and emergence fry success between and among sites in relation to habitat characteristics. We observed considerable variability in the timing, magnitude, and duration of spawning among study areas (streams), in part as a function of a variable, multipeaked hydrograph. Nevertheless, across study areas, >70% of redds were constructed on the final descending limb …


Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg Jul 2011

Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg

Watershed Sciences Faculty Publications

No abstract provided.


Mercury And Selenium Bioaccumulation In The Stromatolite Community Of The Great Salt Lake, Utah, Usa, Wayne A. Wurtsbaugh Jan 2011

Mercury And Selenium Bioaccumulation In The Stromatolite Community Of The Great Salt Lake, Utah, Usa, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.


Lakes As Buffers Of Stream Dissolved Organic Matter (Dom) Variability: Temporal Patterns Of Dom Characteristics In Mountain Stream-Lake Systems, K. J. Goodman, Michelle A. Baker, Wayne A. Wurtsbaugh Jan 2011

Lakes As Buffers Of Stream Dissolved Organic Matter (Dom) Variability: Temporal Patterns Of Dom Characteristics In Mountain Stream-Lake Systems, K. J. Goodman, Michelle A. Baker, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Lakes within fluvial networks may affect dissolved organic matter (DOM) dynamics in streams by dampening spring DOM snowmelt flushing responses and/or by increasing summer DOM production. We assessed the temporal variability of dissolved organic carbon (DOC) concentration and DOM characteristics (specific ultraviolet absorbance (SUVA254); DOC:dissolved organic nitrogen (DOC:DON)), as well as DOC export in seven paired lake inflows and outflows in the Sawtooth Mountain lake district, Idaho. We hypothesized that lakes would decrease stream DOM temporal variability and increase DOM export as a result of autotrophic production. We correlated DOM variability with landscape factors to evaluate potential drivers of DOM …


Absence Of Predation Eliminates Coexistence: Experience From The Fish-Zooplankton Interface, Z. M. Gilwicz, Wayne A. Wurtsbaugh, E. Szymansk Jan 2010

Absence Of Predation Eliminates Coexistence: Experience From The Fish-Zooplankton Interface, Z. M. Gilwicz, Wayne A. Wurtsbaugh, E. Szymansk

Watershed Sciences Faculty Publications

Examples from fishless aquatic habitats show that competition among zooplankton for resources instigates rapid exclusion of competitively inferior species in the absence of fish predation, and leads to resource monopolization by the superior competitor. This may be a single species or a few clones with large body size: a cladoceran such as Daphnia pulicaria, or a branchiopod such as Artemia franciscana, each building its population to a density far higher than those found in habitats with fish. The example of zooplankton from two different fish-free habitats demonstrates the overpowering force of fish predation by highlighting the consequences of its absence. …


Nutrient Limitation Of Phytoplankton By Nitrogen And Phosphorus: Erosion Of The Phosphorus Paradigm, Wayne A. Wurtsbaugh, William M. Lewis Iii Jan 2009

Nutrient Limitation Of Phytoplankton By Nitrogen And Phosphorus: Erosion Of The Phosphorus Paradigm, Wayne A. Wurtsbaugh, William M. Lewis Iii

Watershed Sciences Faculty Publications

No abstract provided.


Mercury In The Biostrome Community Of The Great Salt Lake, Wayne A. Wurtsbaugh, Caleb Izdepski Jan 2009

Mercury In The Biostrome Community Of The Great Salt Lake, Wayne A. Wurtsbaugh, Caleb Izdepski

Watershed Sciences Faculty Publications

No abstract provided.


Freshwater Responses To Nitrogen And Phosphorus Pollution And A Case Study Of Cutler And Dingle Marsh Wetlands, Wayne A. Wurtsbaugh Jan 2009

Freshwater Responses To Nitrogen And Phosphorus Pollution And A Case Study Of Cutler And Dingle Marsh Wetlands, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.


Limnological Analyses Of Cutler Reservoir And Dingle Marsh With Respect To Eutrophication, J. D. Abbott, Deb Collins, Colin Cook, Dan Lamarra, Ryan Leonard, Ben Marret, Justin Stout, Gilbert Rowley, Jeremy Rowley, Wayne A. Wurtsbaugh Jan 2009

Limnological Analyses Of Cutler Reservoir And Dingle Marsh With Respect To Eutrophication, J. D. Abbott, Deb Collins, Colin Cook, Dan Lamarra, Ryan Leonard, Ben Marret, Justin Stout, Gilbert Rowley, Jeremy Rowley, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Cutler Reservoir is located in Cache county, Utah and was created for the purposes of irrigation, water storage and flood control. High nutrient loading to Cutler has raised concerns about the health of this system and has resulted in it being listed on the state's 303(d) list of impaired waters. The TMDL plan being drafted for Cutler lists dissolved oxygen and phosphorous as the key issues of concern. The underlying problem created by nutrient loading is eutrophication. If Cutler is to remain as a valuable source of recreation, wildlife habitat, and water for the Cache Valley we must understand the …


Nutrient Loading And Eutrophication In The Great Salt Lake, Wayne A. Wurtsbaugh Nov 2008

Nutrient Loading And Eutrophication In The Great Salt Lake, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.


Spatial Analyses Of Trophic Linkages Between Basins In The Great Salt Lake, Wayne A. Wurtsbaugh, David Naftz, Shane Bradt Jan 2006

Spatial Analyses Of Trophic Linkages Between Basins In The Great Salt Lake, Wayne A. Wurtsbaugh, David Naftz, Shane Bradt

Watershed Sciences Faculty Publications

Although the Great Salt Lake is frequently treated as if it were a single body of water, the natural bays and transportation causeways have divided it into a system of four bays. The bays, however, do not function independently because water, nutrients and other contaminants flow between them. The purpose of our study was to analyze the water quality in three of the bays (Farmington, Bear River and Gilbert), to determine fluxes of nutrients between them, and to determine how this was influencing brine shrimp populations in the lake. Discharge and nutrient concentrations were measured at constrictions separating the three …


Continuing Analysis Of Phytoplankton Nutrient Limitation In Farmington Bay And The Great Salt Lake, Wayne A. Wurtsbaugh, Amy M. Marcarelli Apr 2005

Continuing Analysis Of Phytoplankton Nutrient Limitation In Farmington Bay And The Great Salt Lake, Wayne A. Wurtsbaugh, Amy M. Marcarelli

Watershed Sciences Faculty Publications

Farmington Bay is a nutrient-enriched, highly eutrophic embayment of the Great Salt Lake. The highly variable salinity of the bay influences what species of plankton can survive there. Previous analyses suggested that cyanobacteria (blue-green algae) may not be able to survive or fix atmospheric nitrogen at high salinities, thus maintaining the lake in a nitrogen-limited state. To determine the interacting influence of nutrients and salinity on the growth and nitrogen fixation of plankton we performed a 28-day bioassay with water from Farmington and Gilbert Bays in October 2004. We tested the response of the plankton to additions of nitrogen (N) …


Ecological Analysis Of Nutrient, Plankton And Benthic Communities In Farmington Bay And The Great Salt Lake, Utah (2004), Amy M. Marcarelli, Wayne A. Wurtsbaugh Feb 2005

Ecological Analysis Of Nutrient, Plankton And Benthic Communities In Farmington Bay And The Great Salt Lake, Utah (2004), Amy M. Marcarelli, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

In Fall 2004, the Aquatic Ecology Practicum class at Utah State University finished a third year of research on limnological and ecological characteristics of Farmington Bay and Gilbert Bays of the Great Salt Lake. Our previous research has produced interesting findings in Farmington Bay, including hypereutrophy (Marcarelli et a!. 2001), high phosphorus loading into the Bay, overnight water column anoxia linked to high winds (Wurtsbaugh et a!. 2002), potential predator control of brine shrimp, and high levels of hydrogen sulfide in the sediment and deep brine layer (Marcarelli et a!. 2003). These class findings have lead to increased interest in …


Analysis Of Phytoplankton Nutrient Limitation In Farmington Bay And The Great Salt Lake, Wayne A. Wurtsbaugh, Amy M. Marcarelli Jun 2004

Analysis Of Phytoplankton Nutrient Limitation In Farmington Bay And The Great Salt Lake, Wayne A. Wurtsbaugh, Amy M. Marcarelli

Watershed Sciences Faculty Publications

The Great Salt Lake is bordered to the south and east by a growing metropolitan area that contributes high nutrients to Farmington Bay. This large bay is eutrophic, and there is concern that continued increases in effluents from the Salt Lake City area could extend to impact the much larger, and currently less productive, Gilbert Bay. This study focused on determining how nutrient supplies might limit, and therefore control, algal populations in Farmington Bay and Gilbert Bay at different salinities. We tested both short and long-term responses of algal growth using laboratory nutrient addition bioassays in the summer and fall …


Hydrogen Sulfide In Farmington Bay And The Great Salt Lake: A Potential Odor-Causing Agent, Wayne A. Wurtsbaugh, Amy M. Marcarelli Mar 2004

Hydrogen Sulfide In Farmington Bay And The Great Salt Lake: A Potential Odor-Causing Agent, Wayne A. Wurtsbaugh, Amy M. Marcarelli

Watershed Sciences Faculty Publications

Odors from Farmington Bay and/or the Great Salt Lake frequently impact residents of Salt Lake and Davis counties, but the agent causing the problem and the origin of the odor is uncertain. Hydrogen sulfide (H2S) gas is produced in the deeper layers of water in Farmington Bay and Gilbert Bay in the Great Salt Lake, but these deeper waters are generally part of high salinity deep-brine layers that are resistant to wind mixing. Hydrogen sulfide has a "rotten-egg" odor and is a likely component contributing to the "lake stink." The goals of this study were to determine (1) whether wind …


Continuing Studies Of Water Quality In Farmington Bay And The Great Salt Lake, Utah, Amy M. Marcarelli, Wayne A. Wurtsbaugh May 2003

Continuing Studies Of Water Quality In Farmington Bay And The Great Salt Lake, Utah, Amy M. Marcarelli, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

For the past three years, an Aquatic Ecology Practicum class at Utah State University has conducted research examining the limnology of Farmington Bay. In 2000, our class discovered that Farmington Bay could be classified as hypereutrophic, and had significantly higher levels of chlorophyll and phytoplankton than the Great Salt Lake proper (Marcarelli et al. 2001). In 2001, individual student projects identified high phosphorus loading into Farmington Bay from surrounding sewage treatment plants, brine shrimp biomass five times lower than in the Great Salt Lake, and that the water in the bay lost all oxygen on a windy night in October …


Comparative Analysis Of Pollution In Farmington Bay And The Great Salt Lake, Utah, Wayne A. Wurtsbaugh, Amy M. Marcarelli, Cameron Christison, Joel Moore, Donovan Gross, Sophia Bates, Sara Kircher Feb 2002

Comparative Analysis Of Pollution In Farmington Bay And The Great Salt Lake, Utah, Wayne A. Wurtsbaugh, Amy M. Marcarelli, Cameron Christison, Joel Moore, Donovan Gross, Sophia Bates, Sara Kircher

Watershed Sciences Faculty Publications

Farmington Bay covers 94 mi2 (260 km2) in the SW comer of the Great Salt Lake, and is essentially a separate lake because it is enclosed by Antelope Island and a causeway leading to the island from the mainland. The bay has received wastes from the adjoining Salt Lake City metropolitan area for decades. Because of water quality concerns for Farmington 8ay, the Aquatic Ecology Laboratory class at Utah State University studied the bay and a nearby control site (Bridger Bay) in the Great Salt Lake during the fall of 2001. Field sampling and laboratory experiments, as well as other …


The Role Of An Invasive Exotic Plant On The Structure Of Aquatic Invertebrate Assemblages: Tamarix In The Southwest United States, Bert Lewis May 1998

The Role Of An Invasive Exotic Plant On The Structure Of Aquatic Invertebrate Assemblages: Tamarix In The Southwest United States, Bert Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Over the past 100 years, riparian vegetation communities throughout the Southwest United States have been extensively invaded by Tamarix spp. (saltcedar). Saltcedar derives its common name from its physiological adaptation to excrete salts. The production of Tamarix detritus with associated secondary chemicals may affect the quality of aquatic invertebrate food and habitat resources. An alteration in food and habitat quality may affect the composition and structure of aquatic invertebrate assemblages.

A series of experiments was conducted contrasting aquatic invertebrate assemblage densities, colonization rates, and growth rates associated with Tamarix versus native vegetation, Populus fremontii (cottonwood) and Salix exigua (willow), to …


Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh, Kirsten L. Gallo Jan 1997

Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell 1997, Wayne A. Wurtsbaugh, Kirsten L. Gallo

Watershed Sciences Faculty Publications

Physical characteristics of lakes are highly interrelated with biological characteristics. We measured and analyzed the physical characteristics of two side canyons in order to better understand differences in productivity between side canyons and the main channel and to provide general information on the characteristics of the lake.


Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell, Wayne A. Wurtsbaugh, Kirsten L. Gallo Jan 1996

Comparison Of The Aquatic Ecology Of Side-Canyons And The Main Channel Of Lake Powell, Wayne A. Wurtsbaugh, Kirsten L. Gallo

Watershed Sciences Faculty Publications

From 18-21 April 1996, students in a Utah State University class (Aquatic Ecology Laboratory; FW 560) measured limnological and fisheries characteristics in two side canyons (Halls Creek Bay and Moki Canyon) and the main channel of Lake Powell. Inclement weather precluded sampling of two other side canyons. Most of the sub-projects, directed by indiVIdual students, addressed the following two hypotheses: (1) productivity gradients existed from the inflows of the side canyons toward the main channel and; (2) productivity was higher in the side canyons than in the main channel of the lake. In most cases, parameters were measured at 3-5 …


Brine Shrimp Ecology In The Great Salt Lake, Utah, Wayne A. Wurtsbaugh Jun 1995

Brine Shrimp Ecology In The Great Salt Lake, Utah, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

Hypersaline lakes are noted for their simple communities which facilitate understanding ecological interactions (Williams et al. 1990; Wurtsbaugh 1992; Jellison and Melack 1988). Nevertheless, we still cannot easily predict how environmental changes will effect the population dynamics in these lakes, at least in part because even these simple ecosystems may be more complex than we .realize. Many hypersaline lakes are dominated by the brine shrimp Artemia spp. The production of brine shrimp is often very high because the terminal, saline lakes accumulate nutrients that make them rich, and because the short food chains in them (nutrients-->phytoplankton-->brine shrimp) minim …


The Trophic Gradient In Lake Powell, Wayne A. Wurtsbaugh, G. Steinhart Jan 1995

The Trophic Gradient In Lake Powell, Wayne A. Wurtsbaugh, G. Steinhart

Watershed Sciences Faculty Publications

From April 21 st to April 25th, 1995 students from Utah State University's FW 462 class sampled the trophic gradient in Lake Powell between Bullfrog (Mile 99) and Hite Marinas (Mile 144). We sampled at 3-12 stations along the gradient, depending on the parameter measured. The purpose of the trip was three-fold. First, the primary objective of the class was to provide field and laboratory experiences in aquatic ecology for the students. Secondly, we wished to provide data on the trophic environment that the endangered razorback sucker larvae from the Colorado River would encounter when the entered the reservoir. Thirdly, …


Acidic Deposition, Ecosystem Processes, And Nitrogen Saturation In A High Elevation Southern Appalachian Watershed, C. S. Nodvin, H. Van Miegroet, S. E. Lindberg, N. S. Nicholas, D. W. Johnson Jan 1995

Acidic Deposition, Ecosystem Processes, And Nitrogen Saturation In A High Elevation Southern Appalachian Watershed, C. S. Nodvin, H. Van Miegroet, S. E. Lindberg, N. S. Nicholas, D. W. Johnson

Watershed Sciences Faculty Publications

High-elevation red spruce-Fraser fir forests in the Southern Appalachian mountains: 1) receive among the highest rates of atmospheric deposition measured in North America, 2) contain old-growth forests, 3) have shown declines in forest health, 4) have sustained high insect-caused fir mortality, and 5) contain poorly buffered soils and stream systems. High rates of nitrogen and sulphur deposition (sim1900 and sim2200 Eq·ha–1·yr–1, respectively) are dominated by dry and cloud deposition processes. Large leaching fluxes of nitrate-nitrogen (100–1400 Eq·ha–1·yr–1) occur within the soil profile. We have expanded the study to the watershed scale with monitoring of: precipitation, throughfall, stream hydrology, and stream …


Snake River Sockeye Salmon Habitat And Limnological Research, David Teuscher, Doug Taki, Wayne A. Wurtsbaugh Jan 1995

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 (1968) 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 1990, only 14 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 …