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Sheep Bedding In The Centennial Mountains Of Montana And Idaho: Effects On Vegetation, Steven S. Seefeldt, April B. Leytem

Western North American Naturalist

In summer, bands of sheep are grazed in western North American mountains. At night the sheep are concentrated into bedding areas. In the study area, each bedding area is only utilized by sheep for one night a year for 2 out of 3 years. Vegetation in the bedding areas was compared to vegetation outside these areas. Both perennial forb cover and total perennial cover were greater outside (48% and 61%, respectively) than inside (29% and 36%, respectively) the bedding areas. Annual forb cover one year after sheep grazing was greater inside (17%) bedding areas than outside (5%). Immediately after sheep …

Patterns In Shoreline Vegetation And Soils Around Lake Mohave, Nevada And Arizona: Implications For Management, Nita Tallent, Maliha Nash, Chad L. Cross, Lawrence R. Walker

Western North American Naturalist

Lake Mohave, on the lower Colorado River in Nevada and Arizona, was created by the construction of Davis Dam for power generation, flood control, and water supply. Management has led to the periodic lowering of the water level of the reservoir (drawdown), such that it reveals a gradient of zones around the margins of the reservoir that range from frequently inundated to frequently dry. The initial filling of Lake Mohave flooded the preexisting native riparian woodlands of Populus-Salix (cottonwood-willow), creating a new shoreline and plant community. We analyzed the spatial distribution of the plant species that dominate the plant community …

Activity Patterns Of Black Bears In Relation To Sex, Season, And Daily Movement Rates, Jesse S. Lewis, Janet L. Rachlow

Western North American Naturalist

Activity patterns of animals can vary depending on both endogenous and environmental factors. Although black bears exhibit substantial variation in activity across the year, relatively little is known about how daily activity patterns and associated movement rates differ among sex and age classes across seasons. We used fine-scale movement data from black bears fitted with GPS collars to evaluate movement and activity patterns across sex and age classes for daily and seasonal time periods in relation to mating and foraging behavior. Black bears were most active during crepuscular time periods, moderately active during the day, and least active at night, …

The Ocelot (Leopardus Pardalis In Northern Texas, With Comments On Its Northern Biogeography, Frederick B. Stangl Jr., John H. Young

Western North American Naturalist

A road-killed specimen of a large male ocelot (Leopardus pardalis) was salvaged on March 2010 from Palo Pinto County in north central Texas. Our review of the northern biogeography of the species indicates that the specimen is not out of historical context. The possibility that the animal represents a broader range of sparsely distributed individuals within the elusive cat’s known historical range deserves consideration.


Un ocelote (Leopardus pardalis) muerto de sexo masculino y de tamaño grande fue recuperado en una carretera del Condado Palo Pinto en el centro-norte de Texas en Marzo del año 2010. Una …

Greater Sage-Grouse Movements And Habitat Use During Winter In Central Oregon, Jennifer R. Bruce, W. Douglas Robinson, Steven L. Petersen, Richard F. Miller

Western North American Naturalist

Greater Sage-Grouse (Centrocercus urophasianus) depend on sagebrush habitat for food and cover during winter, yet few sage-grouse winter ecology studies have been conducted. During January and February 2007, we monitored 22 radio-collared sage-grouse (7 females and 15 males) in central Oregon to characterize winter habitat use and movement patterns. We estimated distances traveled between locations on a weekly basis and quantified habitat characteristics at locations used by male and female sage-grouse. The birds we collared moved extensively across the landscape, using approximately 1480 km². Sagebrush canopy height in sites used by sage-grouse varied from 0.25 to …

Limited Plasticity Of Biomass Allocation In Alpine Forbs, Pikes Peak, Colorado, Michael M. Myerburg, James J. Ebersole, Lauren G. Shoemaker, M. Shane Heschel

Western North American Naturalist

Alpine plant species are thought to have limited phenotypic plasticity, but few data exist on forbs. We assessed plasticity in allocation of biomass to belowground and aboveground parts and to reproduction in 5 forb species from a 50-year-old disturbance and adjacent undisturbed areas in an alpine dry meadow. Three of the species, mostly those with variable numbers of stems per genet, increased in size in the disturbed areas. All 5 forbs showed very limited plasticity in allocation of biomass. Lack of phenotypic plasticity in these forbs may limit their ability to respond to future changes in environment.


Se cree que …

Front Matter, Vol. 71 No. 3

Western North American Naturalist

No abstract provided.

Natural History Of Maguire Primrose, Primula Cusickiana Var. Maguirei (Primulaceae), Jacob B. Davidson, Paul G. Wolf

Western North American Naturalist

Natural history information for rare plants can help land managers better understand the threats to extinction that a taxon may face. Our focus is on the natural history of Maguire primrose (Primula cusickiana var. maguirei, Primulaceae), an endemic, threatened plant found along a narrow corridor within a single canyon in northern Utah. We examined floral morphology, air temperature, relative humidity during flowering, dichogamy, blooming period, and visits from flying insects. As with most Primula,Maguire primrose displays distinct floral distyly. Within the distylous flowers, 17% of our samples had a timing difference in the maturation of anthers and stigmas, …

Influence Of Domestic Livestock Grazing On American Pika (Ochotona Princeps) Haypiling Behavior In The Eastern Sierra Nevada And Great Basin, Constance I. Millar

Western North American Naturalist

In a pilot study, I observed a relationship between domestic livestock grazing and location of American pika (Ochotona princeps) haypiles in the eastern Sierra Nevada and several Great Basin mountain ranges. Where vegetation communities adjacent to talus bases (forefields) were grazed, mean distance from the talus borders to the closest fresh haypiles was 30.1 m (SD = 18.9 m, n = 27), and haypiles were found only high in the talus. In ungrazed forefields, mean distance was 1.8 m (SD = 0.9 m, n = 57), and haypiles were found along the low-elevation talus–vegetation border. Where grazing was …

Growth Sensitivity To Drought Of Co-Occurring Pinus Spp. Along An Elevation Gradient In Northern Mexico, Isaac N. Bickford, Peter Z. Fulé, Thomas E. Kolb

Western North American Naturalist

Climate change is predicted to increase the frequency of severe drought, yet little information exists on the impacts of drought on dominant trees of Mexican pine forests, which are among the most biologically diverse forests in the world. We conducted the first comparison of growth sensitivity to drought of two co-occurringPinus species in Mexico to understand whether growth of dominant pines of the Sierra Madre Occidental in northern Mexico is sensitive to drought and temperature variation and to understand how sensitivity differs between tree species and elevations. We sampled and analyzed tree-ring data across a 400-m elevation gradient for …

Vibrational Communication Of Nine California Stonefly (Plecoptera) Species, John B. Sandberg

Western North American Naturalist

The drumming signals of 9 California stonefly species from 8 families are reported. Signal interval patterns of the individual interbeat, intragroup, and intergroup intervals are graphed and used to determine signal type (monophasic, varied beat-interval, diphasic, and grouped). Signals of Kathroperla takhoma Stark & Surdick are described for the first time. New signal characters and signals from additional locations are described for 8 species: Bolshecapnia maculata (Jewett), Calineuria californica (Banks),Doroneuria baumanni Stark & Gaufin, Megaleuctra complicata Claassen, Nemoura spiniloba Jewett, Oemopteryx vanduzeea (Claassen), Pteronarcys princeps Banks, andSierraperla cora Needham & Smith.


Se reportan las señales de tamborileo de …

An Assessment Of The Lethal Thermal Maxima For Mountain Sucker, Luke D. Schultz, Katie N. Bertrand

Western North American Naturalist

Temperature is a critical factor in the distribution of stream fishes. From laboratory studies of thermal tolerance, fish ecologists can assess whether species distributions are constrained by tolerable thermal habitat availability. The objective of this study was to use lethal thermal maxima (LTM) methodology to assess the upper thermal tolerance for mountain sucker Catostomus platyrhynchus, a species of greatest conservation need in the state of South Dakota. Adult fish were captured from wild populations in the Black Hills of South Dakota and acclimated to 20, 22.5, and 25 °C. Four endpoints (3 sublethal, 1 lethal) were recorded, with death being …

End Matter, Vol. 71 No. 3

Western North American Naturalist

No abstract provided.

Fabrication And Application Of Vertically Aligned Carbon Nanotube Templated Silicon Nanomaterials, Jun Song

Theses and Dissertations

A process, called carbon nanotube templated microfabrication (CNT-M) makes high aspect ratio microstructures out of a wide variety of materials by growing patterned vertically aligned carbon nanotubes (VACNTs) as a framework and then infiltrating various materials into the frameworks by chemical vapor deposition (CVD). By using the CNT-M procedure, a partial Si infiltration of carbon nanotube frameworks results in porous three dimensional microscale shapes consisting of silicon-carbon nanotube composites. The addition of thin silicon shells to the vertically aligned CNTs (VACNTs) enables the fabrication of robust silicon nanostructures with edibility to design a wide range of geometries. Nanoscale dimensions are …

Quantifying Mass Sediment Movement In Deer Creek Reservoir During Spring Runoff And Potential Water Quality Impacts, Colin Rodger Ricks

Theses and Dissertations

The accurate prediction of water quality is essential for management of reservoirs used for drinking water supply. Since algae are a major source of taste and odor problems in drinking water, understanding and controlling algal growth and production is an important task. Deer Creek Reservoir supplies drinking water for over one million people in northern Utah and has been highly eutrophic in the past. Despite major reductions in external nutrient loading, including phosphorus, seasonal algal blooms in Deer Creek have not decreased to desired levels. Resuspension of sediment has been suggested as a potential source of internal nutrient loading for …

The Cost Effectiveness Of Individual And Family Therapy For Schizophrenia In Managed Care, Fufan Chiang

Theses and Dissertations

Much research has explored the cost effectiveness of psychotherapy for schizophrenia. However, to date, no studies have investigated the cost effectiveness of family and individual therapy for schizophrenia in the "real world" of managed care. The purpose of the present study is to compare the cost effectiveness of individual and family therapy for schizophrenia in one leading Health Care Insurer: CIGNA. Six years of outpatient data (2001–2006) and more than 2,100 unique schizophrenic outpatients are included. Research questions in this study concern the total treatment costs, the cost effectiveness, recidivism rates and the dropout rates of individual and family outpatient …

Improving Multi-Label Classification By Avoiding Implicit Negativity With Incomplete Data, Derrall L. Heath

Theses and Dissertations

Many real world problems require multi-label classification, in which each training instance is associated with a set of labels. There are many existing learning algorithms for multi-label classification; however, these algorithms assume implicit negativity, where missing labels in the training data are automatically assumed to be negative. Additionally, many of the existing algorithms do not handle incremental learning in which new labels could be encountered later in the learning process. A novel multi-label adaptation of the backpropagation algorithm is proposed that does not assume implicit negativity. In addition, this algorithm can, using a naive Bayesian approach, infer missing labels in …

Total Synthesis Of 4'-Ester Resveratrol Analogs And 8.9-Amido Geldanamycin Analog And Toward The Total Synthesis Of (-)-Englerin A, Yong Wang

Theses and Dissertations

Total Synthesis of 4'-ester Resveratrol Analogs and 8, 9-amido Geldanamycin Analog and toward the Total Synthesis of (-)-Englerin A Yong Wang Department of Chemistry and Biochemistry, BYU Doctor of Philosophy The phytoalexin resveratrol and its 4'-ester analogs have been prepared with a decarbonylative Heck reaction. The deprotecting step has been modified and improved to increase yield and avoid chromatography. A set of resveratrol analogs and resveratrol have been tested with melanoma and pancreatic cell assays. The 8, 9-amido Geldanamycin analog has been synthesized with a convergent route, involving 28 simplified steps in its longest linear sequence. Synthetic methodologies, such as …

Follicular Dendritic Cells, Resting Cd4+ T Cells And Human Immunodeficiency Virus Expression, Changna Wang

Theses and Dissertations

Many events associated with Human Immunodeficiency Virus (HIV) infection/replication occur in and around the germinal centers (GCs) of secondary lymphoid tissues where follicular dendritic cells (FDCs) reside, suggesting that this microenvironment may contribute unique signaling that is important to viral progression. My research focused on characterizing signaling, both positive and negative, contributed by FDCs that affects HIV infection and replication. Specifically, I determined if FDC signals could induce the expression of latent HIV in T cells and if so, to characterize the signaling pathways involved. Moreover, I also examined the ability of FDCs to produce inhibitory signals that might block …

Participational Agency, Stephen C. Yanchar

Faculty Publications

Participational agency is presented as a conceptual account of human action, volition, and possibility. Rooted in hermeneutic and narrative traditions, this view differs from other theorizing about agency (and most psychological theorizing in general) in that it makes no effort to explain human action by virtue of reified constructs. As an alternative to traditional theorizing in this area, participational agency is defined as meaningful engagement in the world and treats the experienced meaningfulness of practical human activity as its central feature. The concept of meaningful engagement is clarified through the presentation of four related themes—situated participation, existential concern, dispositional action, …

Taxonomic And Nomenclatural Rearrangements In Artemisia Subgen. Tridentatae, Including A Redefinition Of Sphaeromeria (Asteraceae, Anthemideae), Sónia Garcia, Teresa Garnatje, E. Durant Mcarthur, Jaume Pellicer, Stewart C. Sanderson, Joan Vallés

Western North American Naturalist

A recent molecular phylogenetic study of all members of Artemisia subgenusTridentatae, as well as most of the other New World endemic Artemisia and the allied genera Sphaeromeria and Picrothamnus, raised the necessity of revising the taxonomic framework of the North American endemic Artemisia. Composition of the subgenusTridentatae is enlarged to accommodate other North American endemics and is organized into 3 sections: Tridentatae, Nebulosae, and Filifoliae. This paper deals with the combination of one section, the amendment of 2 more sections, and the combination in or the reversion to Artemisia of some Sphaeromeria and Picrothamnusspecies. The new names …

Diversification Within The Mexican Vole (Microtus Mexicanus) And The Role Of Post-Pleistocene Climate Change, Dolly L. Crawford, Jerry W. Dragoo, Felisa A. Smith, Andrea N. Chavez

Western North American Naturalist

To examine the partitioning of genetic variation within the Mexican vole (Microtus mexicanus), we analyzed variation within the cytochrome b (cytb, ca. 953 bp) from 44 samples of the Mexican vole from the mountains of the southwestern United States and Mexico. Phylogeographic analyses demonstrated strong support for a western clade and an eastern clade, corresponding to the Sierra Madre Occidental and mountains of the southwestern United States (western clade) and the Sierra Madre Oriental and the Sierra Madre del Sur (eastern clade). Levels of genetic distinctiveness among vole populations in Mexico and the southwestern United States support …

Improving National-Scale Invasion Maps: Tamarisk In The Western United States, Catherine S. Jarnevich, Paul Evangelista, Thomas J. Stohlgren, Jeffery Morisette

Western North American Naturalist

New invasions, better field data, and novel spatial-modeling techniques often drive the need to revisit previous maps and models of invasive species. Such is the case with the at least 10 species of Tamarix, which are invading riparian systems in the western United States and expanding their range throughout North America. In 2006, we developed a National Tamarisk Map by using a compilation of presence and absence locations with remotely sensed data and statistical modeling techniques. Since the publication of that work, our database of Tamarix distributions has grown significantly.

Using the updated database of species occurrence, new predictor variables, …

Native Plants Dominate Understory Vegetation Following Ponderosa Pine Forest Restoration Treatments, Michael T. Stoddard, Christopher M. Mcglone, Peter Z. Fulé, Daniel C. Laughlin, Mark L. Daniels

Western North American Naturalist

Dense ponderosa pine forests in the southwestern United States inhibit understory production and diversity and are susceptible to high-severity wildfire. Restoration treatments involving overstory thinning and prescribed burning are being implemented to increase understory productivity and diversity and to reduce the risk of severe wildfire. However, disturbances associated with treatments may favor invasion of nonnative species, and the severity of the disturbance may be related to the level of nonnative species establishment. We examined understory community composition, species richness, and plant cover responses to 3 stand-scale replicates of 4 different tree-thinning intensities. Restoration treatments altered the composition of the understory …

Seed Bank Dynamics And Habitat Indicators Of Arctomecon Californica, A Rare Plant In A Fragmented Desert Environment, Laura Megill, Lawrence R. Walker, Cheryl Vanier, Debra Johnson

Western North American Naturalist

Protection of endangered desert plant species is frequently complicated by a lack of information about seeds, the most stress-resistant and populous life stage. We studied the relative locations of seeds and plants of a rare endangered herbaceous perennial, the Las Vegas bearpoppy (Arctomecon californica) in seven 1-ha sites randomly located within a 100-ha study area that was slated for development in Las Vegas, Nevada. We also measured the physical and biological attributes of the environment supporting the seeds and plants, including soil hardness, rock cover, cryptogamic crust cover, and associated vegetation.

Arctomecon californica seed density was 0.651 seeds …

Effects Of Elevation On Litter-Size Variation Among Lizard Populations In The Sceloporus Grammicus Complex (Phrynosomatidae) In Mexico, Aurelio Ramírez-Bautista, Adrian Leyte-Manrique, Jonathon C. Marshall, Geoffrey R. Smith

Western North American Naturalist

We examined the effect of elevation on litter-size variation in viviparous lizards of theSceloporus grammicus complex in 10 states of Mexico. Female snout–vent length (SVL) decreased with increasing elevation, and absolute litter size based on embryos also tended to de crease with increasing elevation. However, after controlling for variation in female body size, we found that litter sizes tended to be relatively larger at higher elevation. Elevation therefore appears to influence litter size in these lizards; however, relatively little of the variation is explained by elevation; thus, other factors are likely making substantial contributions to the observed litter-size variation. …

Maternal Investment By Yellowstone Pronghorn Following Winter Habitat Deterioration, Kerey K. Barnowe-Meyer, P. J. White, John A. Byers

Western North American Naturalist

Spring and summer–autumn nutrition are the prime determinants of reproductive investment in most largeherbivore populations, though winter severity is known to affect reproductive rates in some situations. To evaluate the effects of a long-term decline in winter habitat quality, a diet shift away from sagebrush (Artemisia spp.) during winter, and differential habitat selection during spring–autumn on pronghorn (Antilocapra americana) reproduction, we assessed female and fawn condition, maternal investment, and early fawn survival in migrant and nonmigrant portions of the Yellowstone pronghorn population in Montana and Wyoming during 1999–2001. Mean female mass at capture in late winter (46.81 …

Effects Of Habitat On Clutch Size Of Ornate Tree Lizards, Urosaurus Ornatus, Gregory Haenel

Western North American Naturalist

Clutch size is an important determinant of female reproductive success in reptiles. Although female body size explains much variation in clutch size, other important factors include differences in food availability, predation risk, morphology, and demography. Ornate tree lizards, Urosaurus ornatus, display extensive variation in life history traits, including clutch size. Tree lizards primarily use 2 distinct habitat types—trees and rock surfaces—which influence both the performance and morphology of this species and may affect life history traits such as clutch size. As food availability, microclimate, and, potentially, predator escape probabilities differ between these 2 habitats, I predicted that tree- and rockdwelling …

First Record Of Multiple Paternity In The Pygmy Rabbit (Brachylagus Idahoensis): Evidence From Analysis Of 16 Microsatellite Loci, Wilfredo Falcón, Caren S. Goldberg, Lisette P. Waits, Wendy A. Estes-Zumpf, Janet L. Rachlow

Western North American Naturalist

Although promiscuity is believed to be common among leporids, little is known about the mating system of free-ranging pygmy rabbits (Brachylagus idahoensis). We used 16 polymorphic microsatellite markers and DNA extracted from tissue samples of 10 rabbits from 2 litters collected in east central Idaho to evaluate paternity. We incorporated maternal genotypes for better resolution and employed an exclusion approach to detect multiple paternity. Our results demonstrated multiple paternity at 6 of the 16 loci tested for each litter. These findings support the expectation that pygmy rabbits have a promiscuous mating system. It has been proposed that multiple …

Effects Of Wildfire And Postfire Floods On Stonefly Detritivores Of The Pajarito Plateau, New Mexico, Nicole K. M. Vieira, Tiffany R. Barnes, Katharine A. Mitchell

Western North American Naturalist

Wildfires alter the quantity and quality of allochthonous detritus in streams by burning riparian vegetation and through flushing during postfire floods. As such, fire disturbance may negatively affect detritivorous insects that consume coarse organic matter. We assessed how 2 crown fires impacted stonefly detritivores in streams of the Pajarito Plateau, New Mexico. We documented stonefly populations before and after the fires and postfire floods, and compared recovery trajectories among unburned, lightly burned, and severely burned reaches. We also conducted experiments to assess burned detritus as a food resource for Pteronarcella badia Hagen. Specifically, we characterized microbial conditioning, nutrient content, and …