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The focus of this report is the endangered and threatened fishes of the Upper Colorado River system, but a full appreciation would not be possible without an adequate knowledge of the ecosystems in which they live. The six major sections of the report are: abiotic components, biological components, species description, river basin descriptions, major factors inducing environmental change, and urgent needs and recommended research priorities in regard to the upper Colorado River System. (Deal-EIS)
A written survey of 200 Moab residents was used to measure residents' attitudes toward tourism. Three regression models were developed using variables identified in the tourism literature to measure the relative importance of interpersonal contacts with tourists, negative impacts to outdoor-recreation experiences, and community experience in predicting attitudes toward tourism. Interpersonal contacts and recreation impacts both had fairly high predictive capabilities. It was concluded that interactions between recreation visitors/tourists and local residents should be a focus of further research. Data from the Moab resident survey were also used in conjunction with a survey of mountain bikers visiting or living...
Sage-grouse (Centrocercus spp.) populations have declined dramatically throughout the western United States since the 1960s. Increased gas and oil development during this time has potentially contributed to the declines. I investigated impacts of development of natural gas fields on greater sage- grouse (C. urophasianus) breeding behavior, seasonal habitat selection, and population growth in the upper Green River Basin of western Wyoming. Greater sage-grouse in western Wyoming appeared to be excluded from attending leks situated within or near the development boundaries of natural gas fields. Declines in the number of displaying males were positively correlated with decreased distance from leks to gas-field-related...
The deposition of aeolian (windblown) dust is a global phenomenon with significant implications for terrestrial ecosystems. In particular, the geochemical flux of dust can be an important factor for biogeochemical cycling in soils and, in some settings, may influence ecosystem productivity and chemical weathering. To quantify the role of exogenous dust in soils, the flux and composition of dust must be compared with local soil forming factors. In general, the magnitude, particle size, and geochemical composition of dust vary regionally and are primarily dependent on the distance from dust source area. Each winter/spring the San Juan Mountains (SJM) receive a substantial flux of exogenous dust, which most likely...
Soil organic matter content in the cold desert of the Canyonlands physiographic section of the Colorado Plateau is low and poorly studied. In this environment there is a strong temporal offset between soil temperature and moisture. Because of this temporal offset between soil temperature and moisture, turnover of soil organic matter is regulated on the basis of thresholds. When soil moisture is above 9.5% and temperature is below 15.7�C, turnover of soil organic matter is high but when soil temperature is above 15.7�C moisture is limiting and turnover is slow. This threshold based regulation of soil organic matter turnover is different from what occurs in other ecosystems where soil temperature and moisture continuously...
Population genetic structure of boreal toad (Bufo boreas boreas) in Utah: A basis for defining units of conservation, credited to Hogrefe, Todd C, published in 2001.
Categories: Publication;
Types: Citation,
Thesis Citation;
Tags: Boreal toad,
Conservation biology,
Population genetics
A grassland restoration project was conducted in Canyonlands National Park on an area recently disturbed due to construction. Two native grasses (Oryzopsis hymenoides and Stipa comata) were seeded with 18 different soil treatments. Stipa density and relative mycorrhizal colonization were measured. None of the soil treatments resulted in significantly greater Stipa density than the control treatment of seeding only plus water. There was very little correlation between Stipa density and mycorrhizal colonization based on the treatments (r2= 0.011 p = 0.05). Three treatments produced 3 to 5 times the VAN colonization as the control including spring cryptobiotic soil crusts, with and without sugar, and fall soil crusts...
Categories: Publication;
Types: Citation,
Thesis Citation;
Tags: Revegetation,
Vesicular-arbuscular mycorrhizas
Habitat selection by the relict leopard frog (Rana onca): Assessment of vegetation use at two scales
In recent years, two populations of the rare Relict Leopard Frog (Rana onca) have gone extinct. These population extinctions occurred concomitantly with the encroachment of native emergent vegetation into pools in which frogs were usually observed. In order to determine if adult Rana onca prefer more vegetatively open habitats, a radio-telemetry study was conducted. A total of 809 radio telemetry observations were made on 34 frogs from April 2 through December 7, 2004. Binary Logistic Regression was used with both macrohabitat and microhabitat data to compare habitat characteristics between low-use and high-use segments of the spring. A more traditional multiple analysis of variance (MANOVA) approach was also used...
Bromus tectorum impacts soil carbon storage in semiarid grasslands of Canyonlands National Park, credited to Englund, Sylvia Ruth, published in 2004.
Water is essential to life because its unique properties facilitate a vast number of biochemical processes that enable all organisms to exist. Maintenance of proper water concentration in the body is thus a vital activity. Colonization of terrestrial habitats placed organisms in desiccating environments that emphasized problems of water balance. The procurement and economical use of water has since been a central organizing theme in biology and has shaped the morphology, physiology, behavior, and spatial distribution of organisms. In hot, and environments like North American deserts, organisms are faced with especially challenging abiotic conditions characterized by variable and often extreme temperatures, intense...
Categories: Publication;
Types: Citation,
Thesis Citation;
Tags: Anatomy & physiology,
Animals,
Zoology
I studied desert bighorn sheep (Ovis canadensis, nelsoni) behavior and habitat use in response to boating activities during 1985. The percent of total observed time in attention behavior before the boating season, during the boating season, and while riverboats were < 0.8 km from bighorn sheep groups was 1, 1.4, and 12.2, respectively. Estimated energy expenditure did not significantly differ for high riverboat pressures (p > 0.2) or seasonal comparisons (p > 0.1). Habitat use significantly differed for proximity to the river, which was probably related to the summer use of the river for drinking. Moderate, minor, and no responses to passing riverboats were observed 3, 39, s and 58%, respectively. Responses to riverboats...
Categories: Publication;
Types: Citation,
Thesis Citation;
Tags: Ovis canadensis,
Utah,
disturbance,
ethology,
human,
The greenback cutthroat trout (Oncorhynchus clarki stomias) is federally listed as threatened under provisions of the Endangered Species Act of 1973. Listed species require a 5-year status review be performed to ensure that the listing classification of a species is current. This capstone project compiled and researched all readily available information on the species to aid the United States Fish and Wildlife Service in completing an official 5-year Review. Information reviewed included the species? biology, population trends, habitat, threats, and other relevant information. The results of this status review indicated that the species should remain listed as threatened. In addition, 12 recommendations were identified...
We tested the adequacy of standard 30 m riparian buffers for semi-aquatic vertebrate species, using the boreal toad (Bufo boreas boreas) as an example. We monitored toad populations in south-central Utah using radio telemetry during the summers of 2003 and 2004. We found 30 m buffers inadequate for protecting boreal toads and suggest this is likely true for other species as well. Managers must consider several factors when constructing buffers: (1) Buffer requirements may vary by time of year. While we located toads most often in wet habitats, toads commonly utilized upland habitats in late summer, occasionally at distances greater than 100 m from water. (2) A single year’s observation may not be sufficient to...
Mathematical programming models of agricultural production in the Colorado River Upper Basin were integrated with a hydrology model of the Colorado River to assess the impacts of transferring water from irrigation uses in the Upper Basin to urban users in the Lower Basin. One strategy involved a long-term lease of irrigation water on an annual basis. The other assessed a lease-option strategy by the Lower Basin to take Upper Basin water only when needed. The economic impacts measured were changes in regional income, agriculturally generated income, crop production, land use, and input expenditures. Environmental impacts considered were changes in river salinity levels and increased hydropower production resulting...
This study examined activity patterns and habitat use of pygmy rabbits (Brachylagus idahoensis) in mechanically treated and untreated areas in south-central Utah 2005-2008. We monitored fecal pellet plots in continuous sagebrush habitat as well as along treatment edges to record deposition and leporid presence over timed periods. Pygmy rabbit use of big sagebrush was higher than black-tailed jackrabbits (Lepus californicus) and mountain cottontail rabbits (Sylvilagus nuttallii ) (P< 0.01) relative to treated areas (P <0.01). We also compared pygmy rabbit use of areas with continuous sagebrush to residual sagebrush in a sample of mechanically treated areas. Our results suggest a treatment effect with higher (P <0.01)...
Fracture network patterns have been studied in two areas with different structural settings: (a) Dolomitic limestones on Teton anticline, in the frontal part of the fold thrust belt in the Sawtooth Range, Montana and (b) Cedar Mesa sandstones within normal faulted structures in the Canyonlands area, Utah. GIS-based techniques were used to study the two-dimensional distribution of fractures on exposed bedding planes in both areas. Individual fracture characteristics, such as fracture length, orientation, and density were analyzed along with the connectivity pattern of fracture networks. The latter parameter is important in determining whether the fractures are isolated or form extensive connected pathways. Studies...
Changes in the hydrologic equilibrium of a river basin resulting from resource development also produce changes in the quality pattern. since the burden of quality maintenance must be shared by users (just as are quantities) predictions are needed for quality changes which might result from contemplated development at any specified location within the river system. This study reports the development of a computer simulation model of the water and salt flow systems within the Upper Colorado River Basin. Because of the close relationship between the hydrologic and salinity flow systems, an understanding of the hydrologic system is essential to successful management of the salinity system. In this study development...
Categories: Publication;
Types: Citation,
Thesis Citation;
Tags: colorado river basin,
computer models,
flow,
forecasting,
irrigation efficiency,
Introduction of Bromus tectorum (cheatgrass) into western rangelands has had a profound effect on the diversity and health of native ecosystems. Introduced in the late 19th century, B. tectorum has rapidly out-competed native species and colonized large areas of the Great Basin region (Mack, 1981). The objective of this research is to assess changes in soil physical and hydrologic properties on former A. tridentata sites now invaded by B. tectorum and to quantify the scope of the alterations through time. Study site selection was based upon a range of A. tridentata stand replacing fire histories spanning approximately 20 years and subsequent colonization of each fire site by B. tectorum. Fire sites sampled were...
Between 1943 and 1988, four towns in the American West--Uravan, Colorado; Moab, Utah; Grants, New Mexico; and Jeffrey City, Wyoming--twice boomed and busted due, in large part, to their dependence on the uranium industry and the United States federal government. Yellowcake, processed uranium ore, not only impacted these towns' economies but also transformed their landscapes and images. This analysis examines the interplay of changing federal policy, the uranium industry, and the four communities by comparing two company towns--Uravan and Jeffrey City--against the two independent ones, Moab and Grants. This study frames this interaction through five different intervals: the radium and vanadium period, 1910-1942;...
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