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Effects Of Douglas-Fir Beetle (Coleoptera: Scolytidae) Infestations On Forest Overstory And Understory Conditions In Western Wyoming, Joel D. Mcmillin, Kurt K. Allen

Western North American Naturalist

Douglas-fir beetle (Dendroctonus pseudotsugae Hopk.) infestations frequently result from disturbance events that create large volumes of weakened Douglas-fir trees, Pseudotsuga menziesii (Mirb.) Franco. Previous research has focused on determining susceptibility of forest stands to Douglas-fir beetle and predicting the amount of tree mortality from Douglas-fir beetle infestations following disturbance events. Little work has been done on consequent changes in the forest overstory and understory. In the early 1990s, populations of Douglas-fir beetle increased in fire-scorched trees, subsequently infesting undamaged neighboring stands in the Rocky Mountains of western Wyoming, USA. In 1999 transect sampling and 25 pairs of previously infested …

Index [And Table Of Contents] To Volume 63

Western North American Naturalist

No abstract provided.

Plant Invasions In Protected Areas At Multiple Scales: Linaria Vulgaris (Scrophulariaceae) In The West Yellowstone Area, Aníbal Pauchard, Paul B. Alaback, Eric G. Edlund

Western North American Naturalist

Invasive alien plants have long been recognized as a threat to low-elevation, disturbed environments, but the case of Linaria vulgaris Mill. in Yellowstone National Park and Gallatin National Forest shows that invasions can also spread to high-elevation natural reserves. Because invasions in protected areas are a product of complex processes occurring over a broad range of scales, we argue that a multi-scale research approach is needed to capture both patterns and potential mechanisms of the invasion process. Mapping L. vulgaris at the landscape scale, we found the species occupying a broad range of sites, apparently originating from just 2 historical …

A New Record Of Heribaudiella Fluviatilis, A Freshwater Brown Alga (Phaeophyceae), From Oregon, John D. Wehr, Alissa A. Perrone

Western North American Naturalist

Members of the algal class Phaeophyceae (brown algae) are almost entirely marine species. A few genera have been described from freshwater habitats, but their distribution and ecological requirements, especially in North America, are very poorly known. The 1st specimens of a freshwater species of brown algae from Oregon, Heribaudiella fluviatilis, were discovered in 3 localities of the McKenzie River, near McKenzie Bridge and Belknap Springs (44°22′N, 122°00′-15′W). This is the 4th extant population of this species known from the United States. The alga forms distinctive, macroscopic, dark brown patches on rocks in rapidly flowing water. In the McKenzie River …

Responses Of Opossums And Raccoons To Bobcat And Coyote Feces, Philip S. Gipson, Troy R. Livingston, Gerald L. Zuercher, Mark E. Howard

Western North American Naturalist

No abstract provided.

Reproductive Ecology Of Dusky Flycatchers In Montane Meadows Of The Central Sierra Nevada, James W. Cain Iii, Michael L. Morrison

Western North American Naturalist

Avian species with expansive ranges or those that occupy more than one vegetative association may vary in aspects of their life histories across their ranges. The distribution of Dusky Flycatchers encompasses a variety of vegetative associations, including riparian communities. However, much of the literature on this species details studies conducted in upland areas. Our objectives were to describe the breeding ecology and fecundity of Dusky Flycatchers nesting in montane meadows of the central Sierra Nevada, California. We monitored 36 territories and located 37 Dusky Flycatcher nests in 8 meadows. Average clutch size was 3.9 eggs. Egg laying, incubation, and nestling …

Democratization, Ethnicity, And War, Lindsay Baxter

Sigma: Journal of Political and International Studies

No abstract provided.

Vol. 21, Sigma: Journal Of Political And International Studies, Sigma: Journal Of Political And International Studies

Sigma: Journal of Political and International Studies

No abstract provided.

A New Approach To Modeling Vertical Stiffness In Heel-Toe Distance Runners, Iain Hunter

Faculty Publications

Various models have been used to describe distance running technique. Among these, the mass-spring model is fairly simple to use and apply, but when employed as a model, does not predict vertical force accurately especially when a heel strike is exhibited. The purpose of this article is to demonstrate how the mass-spring model can be modified to provide a simple, yet accurate prediction of ground reaction forces in distance running. Sixteen subjects ran on a force instrumented treadmill. Vertical forces during running at a self-selected pace were collected at 500 Hz. Vertical stiffness was calculated using the conventional mass-spring model …

Understanding Why Adult Participants At The World Senior Games Choose A Healthy Diet, Ray M. Merrill, Eric C. Shields

Faculty Publications

Identifying those seniors most likely to adopt a healthy diet, the relative importance they place on certain perceived benefits associated with a healthy diet, and whether these perceived benefits are associated with selected demographic, lifestyle, and health history variables is important for directing effective dietary health promotion programs. Methods: Analyses are based on a cross-sectional convenience sample of 670 seniors aged 50 years and older at the 2002 World Senior Games in St. George, Utah. Data are assessed using frequencies, bivariate analysis, analysis of variance, and multiple logistic regression analysis. Results Fruit and vegetable consumption was significantly higher in individuals …

Predicting Drag Polars For Micro Air Vehicles, Mark Elden Luke

Theses and Dissertations

Drag polars for three Micro Air Vehicles (MAVs) were measured at Reynolds numbers of 70,000, 50,000, 30,000, and 10,000 and compared to predictions generated using the classical approach. The MAVs tested had different configurations and aspect ratios varying from 1.2 to 1.6 and ratios of wetted surface area to planform area from 2.6 to 3.9.

A force balance was used to measure the lift and drag on the MAVs at angles of attack ranging from -5 degrees (or -10 degrees) to 10 degrees. The force balance allowed the MAVs to rotate in the pitching axis. The MAV angle of attack …

Globalizations: The First Ten, Hundred, Five Thousand, And Million Years, David Wilkinson

Comparative Civilizations Review

No abstract provided.

Latin America And Liberation Theology, Dong Sull Choi

Comparative Civilizations Review

No abstract provided.

Kroeber's Cultural Configurations, Sorokin's Culture Mentalities, And Generational Time-Series Analysis: A Quantitative Study Of Civilizations, Dean Keith Simonton

Comparative Civilizations Review

No abstract provided.

John Farrenkopf. Prophet Of Decline: Spengler On World History And Politics, John J. Reilly

Comparative Civilizations Review

No abstract provided.

The World After Modernity, John J. Reilly

Comparative Civilizations Review

No abstract provided.

The Gentics Of Civilization: An Empirical Classification Of Civilizations Based On Writing Systems, Bosworth, Andrew Bosworth

Comparative Civilizations Review

No abstract provided.

Trust Negotiation For Authentication And Authorization In Healthcare Information Systems, Charles D. Knutson, Kent E. Seamons, Tore L. Sundelin, David K. Vawdrey

Faculty Publications

The expanding availability of health information in an electronic format is strategic for industry-wide efforts to improve the quality and reduce the cnst of health care. The implementation of electronic medical record systems has been hindered by inadequate security provisions. This paper describes the use of frust negotiation as a framework for providing authentication and access control services in healthcare information systems. nust negotiation enables two parties with no pre-existing relationship to establish the trust necessary to perform sensitive transactions via the mutual disclosure of attributes contained within digital credentials. An extension of this system, surrogate irusf negoikiion is introduced …

Hrt: Decide Based On The Evidence, Sandra Lookinland, Renea L. Beckstrand

Faculty Publications

The effectiveness and safety of hormone replacement therapy (HRT) have been studied since the 1980s. However, much of the available evidence was contradictory, and practitioners were uncertain how to counsel peri- and postmenopausal patients. In this article, recent evidence, both for and against use of HRT in peri- and postmenopausal patients, is compared to past studies with recommendations for practice.

Epidemiology Of Ustilago Bullata Berk. On Bromus Tectorum L. And Implication For Biological Control, Toupta Boguena

Theses and Dissertations

The seedling-infecting pathogen Ustilago bullata Berk. is a naturally occurring biological control agent for cheatgrass (Bromus tectorum L.). The effects of temperature and nutrients on pathogen teliospore germination behavior and the effects of temperature on host seed germination were examined. The effects of temperature on sporidial proliferation, host infection in a temperature-controlled environment and in a field setting for eight populations were investigated. The infection success of Ustilago bullata on Bromus tectorum in cultivated fields as a function of seeding date, inoculation method, inoculum density, supplemental watering, and litter was also investigated. Teliospores germinated faster on potato dextrose agar than …

Recurrence Of Mexican Long-Tongued Bats (Choeronycteris Mexicana) At Historical Sites In Arizona And New Mexico, Paul M. Cryan, Michael A. Bogan

Western North American Naturalist

The Mexican long-tongued bat (Choeronycteris mexicana) is a nectar-eating species that seasonally inhabits the southwestern United States. Since 1906, fewer than 1500 individuals of C. mexicana have been documented throughout the range of the species. We conducted a field survey in Arizona and New Mexico during summer 1999 to check historically occupied areas for recurrence of C. mexicana. We observed C. mexicana occupying a majority (75%, n = 18) of visited sites. Multiple individuals were observed at many sites, including young-of-year. Choeronycteris mexicana roosted in lighted areas close to entrances within mine adits, abandoned buildings, wide rock …

Northern Saw-Whet Owl (Aegolius Acadicus) Migration In The Pacific Northwest, Graham G. Frye, Richard P. Gerhardt

Western North American Naturalist

Northern Saw-whet Owls (Aegolius acadicus) were captured in north central Oregon, USA, during autumn 1999 and 2000 as a pilot study on migration in the Pacific states. We captured 70 individuals, with annual capture rates comparable to those reported for larger studies in the eastern and Midwestern U.S. We investigated differential capture by time of night, time of season, and age. No results were significant due to small samples and brief duration of the study, although some results tended toward significance (P < 0.10). Here we provide a descriptive account of our observations of Northern Saw-whet Owl migration in north central Oregon, the first such study to be presented for the Pacific states.

Dispersal Of Sagebrush-Steppe Seeds By The Western Harvester Ant (Pogonomyrmex Occidentalis), John F. Mull

Western North American Naturalist

Like many seed-harvesting ants, the western harvester ant (Pogonomyrmex occidentalis) can act as both a predator and a seed disperser. Dispersal results when seeds are dropped en route to the nest, are left in nest granaries when colonies die or are abandoned, or are removed from granaries and discarded in nest middens. This study examined the density and species identity of seeds discarded in harvester ant nest middens and compared them with those found in nearby soils. Nineteen species of seeds were recovered from middens, compared with 13 species in 5-m reference areas and 9 species in adjacent …

Roosting Behavior Of The Mexican Free-Tailed Bat (Tadarida Brasiliensis) In A Highway Overpass, Mario P. Sgro, Kenneth T. Wilkins

Western North American Naturalist

A colony of Mexican free-tailed bats (Tadarida brasiliensis) roosting in an interstate highway overpass in Belton, Bell County, Texas, was studied weekly from 28 June to 21 November 1996 (except for the week of 4 July). We examined 2 aspects of roosting behavior: site-specific fidelity to locations within the roost and gender-related segregation within the roost. Colony estimates based on guano production showed a marked decrease in the number of bats from 19 to 26 July; many of these departing bats were adult females. No female bats sampled after this interval were pregnant. Male bats outnumbered females on …

Geobotany Of The Niobrara Chalk Barrens In Colorado: A Study Of Edaphic Endemism, Sylvia Kelso, Nathan W. Bower, Kirsten E. Heckmann, Paul M. Beardsley, Darren G. Greve

Western North American Naturalist

The chalk barrens of the Niobrara Formation in the Arkansas River valley of Colorado exhibit a high degree of plant endemism and rarity. We examined their geochemistry and structure as well as the reproductive ecology of their signature species Mirabilis rotundifolius to assess factors influencing endemism. While no single component consistently identified the barren soils, the natural locations that support Mirablilis can be identified using elemental profiles from a cluster analysis of soil extracts. Because seeds germinate and plants proliferate in transplant gardens with non-calcic soils, bedrock and soil chemistry do not appear to be determinant components of endemism. Mirabilis …

Estimates Of The Incidence Of Mistletoes In Pinyon-Juniper Woodlands Of The Coconino National Forest, Arizona, Carolyn M. Daugherty, Robert L. Mathiasen

Western North American Naturalist

The relative incidence of mistletoes found in pinyon-juniper woodlands is estimated for the Coconino National Forest, Arizona, using a roadside survey. Approximately 50% of the pinyon-juniper woodlands surveyed were infested with juniper mistletoes (Phoradendron juniperinum or P. capitellatum). In contrast, only about 12% of the areas surveyed were infested with pinyon dwarf mistletoe (Arceuthobium divaricatum). In these infested woodlands, 70% with juniper mistletoes and 44% with pinyon dwarf mistletoe were lightly infested. Most areas where pinyon dwarf mistletoe populations were observed (90%) also had juniper mistletoe (P. juniperinum) present, but many juniper mistletoe populations …

Insect-Mediated Pollination In Slickspot Peppergrass, Lepidium Papilliferum L. (Brassicaceae), And Its Implications For Population Viability, Ian C. Robertson, Danielle Klemash

Western North American Naturalist

Field experiments on the pollination biology of slickspot peppergrass, Lepidium papilliferum L. (Brassicaceae), a rare species endemic to microsites in sagebrush-steppe habitat in southwestern Idaho, were conducted at 2 sites from May to July 2001. Site KB contained over 10,000 plants, whereas site WG contained less than 150 plants. Insect exclusion experiments revealed that seed production in L. papilliferum is dependent on insect-mediated pollination; median percent seed set dropped from 70% to 2% when insects were excluded from flowers. A total of 25 insect families from 5 orders visited L. papilliferum flowers: 24 families at KB and 11 families at …

Occurrence Of The California Red-Legged Frog (Rana Aurora Draytonii) In Nevada, Usa, Jamie Kristine Reaser

Western North American Naturalist

No abstract provided.

Fall Diet Of Chukars (Alectoris Chukar) In Eastern Oregon And Discovery Of Ingested Lead Pellets, Hanspeter Walter, Kerry P. Reese

Western North American Naturalist

No abstract provided.

Assortative Mating In Insects: Sexual Selection Vs. Sampling Artifact, Ruth Bernstein, Stephen Bernstein

Western North American Naturalist

In this report we analyze patterns of size-assortative mating in an insect genus by (1) describing the consistency and strength of assortative mating among populations of a species and among species of a genus, and (2) determining the role of sampling artifacts in generating this nonrandom pattern of mating. Our data consist of 18 samples of soldier beetles (8 species of the genus Chauliognathus) from 17 sites within the southwestern United States. Of the 18 samples, just 6 exhibited significant correlations between elytron lengths of mating pairs. We show how these and other significant correlations are generated by 3 …