bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of Mycobacterium tuberculosis DNA in CD34+ peripheral blood mononuclear cells of Ugandan adults with latent infection: a cross-sectional and nested prospective study
Authors: Mayito Jonathan , Andia Biraro Irene , T. Reece Stephen , R. Martineau Adrian , P. Kateete David
Published: July 2020

Background: Tuberculin skin test and interferon gamma release assay (IGRA) show limitations in diagnosing latent tuberculosis infection (LTBI) and poorly predict progression to active tuberculosis. This study will explore detection of Mycobacterium tuberculosis (M.tb) DNA in CD34+ peripheral blood mononuclear cells (PBMCs) as a biomarker for LTBI and monitoring chemoprophylaxis response.

Methods: In a cross-sectional study, 120 household contacts (60 HIV positive and 60 HIV negative) will be recruited. Also, 10 patients with sputum positive pulmonary tuberculosis and 10 visitors from low incidence countries with no history of TB treatment will be recruited as positive and negative controls, respectively. Participants will donate 100 ml (50 ml for TB patients) of blood to isolate PBMCs using density gradient centrifugation. Isolated PBMCs will be separated into CD34+ and CD34- enriched cellular fractions. DNA from each fraction will be purified, quantified and subjected to droplet digital PCR targeting IS6110 (a M.tb Complex multi-copy gene) and rpoB, a single copy gene. Also, 4 ml of blood will be drawn for IGRA. In a nested prospective study, 60 HIV positive participants will be given 300 mg of Isoniazid Preventive Therapy (IPT) daily for six months, after which they will donate a second 100 ml blood sample that will be processed as described above.

Data from the cross-sectional study will be analysed to determine the proportion of individuals in whom M.tb DNA is detectable in CD34+ and CD34- fractions and number of M.tb genomes present. Data from the prospective study will be analysed to compare the proportion of individuals with detectable M.tb DNA in CD34+ and CD34- fractions, and median M.tb genome copy number, post vs pre-IPT.

Discussion: This study will determine whether detection of M.tb DNA in CD34+ PBMCs holds promise as a biomarker for LTBI and monitoring chemoprophylaxis response.
Mortality risk factors among National Football League players: An analysis using player career data
Authors: Ehrlich Justin , Kmush Brittany , Walia Bhavneet , Sanders Shane
Published: July 2020

In general, National Football League (NFL) players tend to live longer than the general population. However, little information exists about the long-term mortality risk in this population. Frequent, yet mild, head trauma may be associated with early mortality in this group of elite athletes. Therefore, career playing statistics can be used as a proxy for frequent head trauma. Using data from Pro Football Reference, we analyzed the association between age-at-death, position, and NFL seasons-played among 6,408 NFL players that were deceased as of July 1, 2018. The linear regression model allowing for a healthy worker effect demonstrated the best fit statistics (F-statistic = 9.95, p-value = 0.0016). The overall association of age-at-death and seasons-played is positive beginning at the 10.75 and 10.64 seasons-played point in our two models that feature seasons-played and seasons-played squared as explanatory variables. Previous research that does not account for this survivorship bias/healthy worker effect may not adequately describe mortality risk among NFL players.
Recent advances in understanding and managing acne
Authors: Kurokawa Ichiro , Nakase Keisuke
Published: July 2020

Multidisciplinary investigations into the pathogenesis of acne have significantly progressed over the past three years. Studies of the etiology of acne from the perspectives, for example, of sebaceous gland biology, sebum, genetics, keratinization, differentiation, hair cycles, immunology, bacteriology, and wound healing have elucidated its pathogenesis. This has led to the development of new therapies and paved the way for advanced studies that will enable the further evolution of acne treatment.
Models of service delivery for optimizing a patient’s first six months on antiretroviral therapy for HIV: an applied research agenda
Authors: Rosen Sydney , Grimsrud Anna , Ehrenkranz Peter , Katz Ingrid
Published: July 2020

Differentiated models of service delivery (DSD models) for HIV treatment in sub-Saharan Africa were conceived as a way to manage rapidly expanding populations of experienced patients who are clinically “stable” on antiretroviral therapy (ART). Entry requirements for most models include at least six months on treatment and a suppressed viral load. These models thus systematically exclude newly-initiated patients, who instead experience the conventional model of care, which requires frequent, multiple clinic visits that impose costs on both providers and patients. In this open letter, we argue that the conventional model of care for the first six months on ART is no longer adequate. The highest rates of treatment discontinuation are in the first six-month period after treatment initiation. Newly initiating patients are generally healthier than in the past, with higher CD4 counts, and antiretroviral medications are better tolerated, with fewer side effects and substitutions, making extra clinic visits unnecessary. Improvements in the treatment initiation process, such as same-day initiation, have not been followed by innovations in the early treatment period. Finally, the advent of COVID-19 has made it riskier to require multiple clinic visits. Research to develop differentiated models of care for the first six-month period is needed. Priorities include estimating the minimum number and type of provider interactions and ART education needed, optimizing the timing of a patient’s first viral load test, determining when lay providers can replace clinicians, ensuring that patients have sufficient but not burdensome access to support, and identifying ways to establish a habit of lifelong adherence.
The relationship between donor-recipient genetic distance and long-term kidney transplant outcome
Authors: Stapleton Caragh P. , Lord Graham M. ,   UK and Ireland Renal Transplant Consortium, Conlon Peter J. , Cavalleri Gianpiero L.
Published: July 2020

Background: We set out to quantify shared genetic ancestry between unrelated kidney donor-recipient pairs and test it as a predictor of time to graft failure.  

Methods: In a homogenous, unrelated, European cohort of deceased-donor kidney transplant pairs (n pairs = 1,808), we calculated, using common genetic variation, shared ancestry at the genic (n loci=40,053) and genomic level. We conducted a sub-analysis focused on transmembrane protein coding genes (n transcripts=8,637) and attempted replication of a previously published nonsynonymous transmembrane mismatch score. Measures of shared genetic ancestry were tested in a survival model against time to death-censored graft failure.

Results: Shared ancestry calculated across the human leukocyte antigen (HLA) significantly associated with graft survival in individuals who had a high serological mismatch (n pairs = 186) with those who did not have any HLA mismatches indicating that shared ancestry calculated specific loci can capture known associations with genes impacting graft outcome. None of the other measures of shared ancestry at a genic level, genome-wide scale, transmembrane subset or nonsynonymous transmembrane mismatch score analysis were significant predictors of time to graft failure.

Conclusions: In a large unrelated, deceased-donor European ancestry renal transplant cohort, shared donor-recipient genetic ancestry, calculated using common genetic variation, has limited value in predicting transplant outcome both on a genomic scale and at a genic level (other than at the HLA loci).
Fire Effects on the Biological and Geological Characteristics of Sediments in Yellowstone Lake: A Basis for Improved Fire Management Policy
Authors: Shero Brian , Singer Jill
Published: July 2020

A number of studies have examined the effect of forest fires on the nutrient and productivity levels of lakes and streams, but no consistent pattern has been identified. In the specific case of Yellowstone Lake, Romme and Knight (1982) and Albin (1979) suggested that cyclic fires in the Yellowstone Lake drainage basin could potentially increase nutrient loading of the lake and thereby increase its productivity.
Post Glacial Fire Frequency and its Relation to Longterm Vegetational and Climatic Changes in Yellowstone Park
Authors: Whitlock Cathy
Published: July 2020

The paleoecologic record provides unique insights into the response of communities to environmental perturbations of different duration and intensity. Climate is a primary agent of environmental change and its long-term effect on the vegetation of the Yellowstone/Grand Teton region is revealed in a regional network of pollen records. Fire frequency is controlled by climate, and as climate changes, so too does the importance of fire in shaping and maintaining spatial patterns of vegetation. The prehistoric record of Yellowstone's Northern Range, for example, shows the response of vegetation to the absence of major fires in the last 150 years (Whitlock et al. 1991; Engstrom et al. in press). In longer records spanning the last 13,000 years, periods of frequent fires are suggested by sediments containing high percentages of lodgepole pine (Pinus contorta) and Douglas-fir (Pseudotsuga menziesii) and high amounts of charcoal (Barnosky et al. 1987; Whitlock in prep.).
Front Matter and Table of Contents
Authors: Plumb Glenn
Published: July 2020

This entry contains the front cover, front matter and back cover.
Biogeography of Invertebrates in Hanging Gardens of the Colorado Plateau
Authors: Stanton Nancy , Buskirk Steven , Fowler James
Published: July 2020

Hanging gardens are relatively small, isolated mesophytic communities surrounded by the xeric environment of canyon walls in the entrenched dendritic drainage pattern of the Colorado Plateau (Welsh 1989a, Malanson 1980, Welsh and Toft 1972). Various sandstone formations such as the NavaJo in Zion National Park serve as aquifers which produce permanent seeps or springs when underlain by impervious layers (Welsh and Toft 1972). These reliable sources of water and the associated processes of erosion and sedimentation, allow the formation of biotic communities that starkly contrast with the surrounding desert. Several endemic plant species have been found in Utah hanging garden surveys (Welsh 1989b, Loope 1977, Welsh and Toft 1972) and Dinosaur National Monument (T. Naumann, personal comm.). Virtually nothing is known about the invertebrate fauna. Our specific research objectives are to (1) survey the plant and invertebrate animal communities of hanging gardens in Zion National Park (ZION) and Glen Canyon National Recreation Area (GLCA), (2) map the geographic distribution of the endemics identified and determine levels of endemism within and among parks; (3) determine levels of similarity between each sampled hanging garden plant and insect community, and to (4) determine similarities among plant communities and among insect communities across gardens.
Rare Plants of Bryce Canyon National Park, Utah
Authors: Peabody Frederick
Published: July 2020

A literature survey has been completed in order to determine plant species that have been considered rare, and also plant species that are potentially rare. Dr. Stan Welsh of the Botany and Range Science Department of Brigham Young University (Provo, Utah) was contacted personally during the field season. His experience in the region has provided a list of additional species that are considered rare for the state of Utah and occur on specific sites near the National Park (Table 1). It is possible that these additional rare species may occur within the boundaries of the park.
Assessment of the Aquatic Plant Community in Jackson Lake, Grand Teton National Park, Wyoming: 1991 Status Report
Authors: Brewer Carol
Published: July 2020

Since the construction of the first dam at the Snake River outlet at Jackson Lake in the early 1900's, the littoral habitat has been subjected to numerous perturbations of varying intensities. Changing water levels, a consequence of reservoir drawdown schedules, alter plant community species composition and distribution over time. From the perspective of a plant, water level changes present a challenge to growth and community persistence. A plant which begins the growing season 2 m deep may be under 4 m of water after spring runoff fills the reservoir. Later in the summer, the same plant may be left at a depth of only 1 m as water is removed from the reservoir during summer drawdown. The magnitude and timing of water level fluctuations may be one of the most important factors regulating macrophyte community processes upslope on the vertical gradient in Jackson Lake (Brewer and Parker 1990). Under normal regulation, annual changes of 3-4 m are sufficient to select for a plant community with a typically weedy phenology (e.g., Elodea canadensis). In natural lakes with substantially lower annual changes in water levels, species that produce seeds annually are favored (e.g., Potamogeton species). Moreover, drawdowns greater than several meters substantially reduce the lake bed area suitable for the development of extensive shallow water plant beds. The most recent perturbations to the littoral habitat in Jackson Lake began in 1978, when the water level was lowered first from 2065 m (normal pool) to somewhere between 2060 - 2062 m. Then in 1985, the surface elevation of Jackson Lake was further lowered to 2057 m to facilitate repair and modification of the Jackson Lake dam. The entire lake bed was seriously impacted during the four years that the dam was being restored. While the lake bed in the borrow zone and the area adjacent to the dam were obviously impacted by repair activities, the entire shallow littoral zone was severely perturbed when previously inundated sediments were exposed for four years. In 1989, repair was completed and the reservoir was allowed to fill back to the normal pool elevation of 2065 m. Because of severe impacts to the littoral habitat and significant reduction of the submergent plant community caused by restoration of the dam, the status of the aquatic plant community was monitored during the summers of 1989-1991. This report summarizes the status of the aquatic plant community three years after repair of the dam was completed.
Population Densities and Community Structure of Birds in Jackson Hole: A Reassessment after 25 Years
Authors: Cody Martin
Published: July 2020

The award covers research expenses for a comparison of bird community structure--species, diversities, densities and distribution, and interspecific interactions--in two habitat types in Jackson Hole/Grand Teton-National Park, 1966-68 data versus 1991-92 data. In 1991 two study sites were re-established in the park, in sites as nearly overlapping as possible sites worked previously in 1966-68. The sites are a) willow scrub habitat, ca. 100 m west of Moran Junction; b) grass-sagebrush/forb meadow, ca. 200 m SE of Moran Junction.
Giardia and Other Parasites of Small Mammals in Grand Teton National Park
Authors: O'Dell William , Watkins Raychel , Moshier Suzanne , Pinter Aelita
Published: July 2020

The objectives of this study are to document the effects and cost of parasitism on vole populations and to determine the potential of small mammals of Grand Teton National Park to serve as reservoirs of human parasites. Specific goals for this year were: (1) to continue surveying small mammals for Babesia microti; (2) to collect and identify ticks found with these animals; (3) to determine if I. eastoni is a tick vector of B. microti; (4) to compare spleen histology of babesiosis in laboratory-infected and uninfected animals; and (5) to continue documentation of the occurrence of Giardia as an intestinal parasite of the montane vole.
Climatic Factors, Reproductive Success and Population Dynamics in the Montane Vole, Microtus montanus
Authors: Pinter Aelita
Published: July 2020

Multiannual fluctuations in population density ("cycles") of small rodents have been known since antiquity (Elton 1942). Numerous hypotheses have been proposed to explain this phenomenon (for reviews see Finerty 1980, Taitt and Krebs 1985). However, none of these hypotheses, alone or in combination, have been able to explain the causality of cycles. The objectives of this long-term study are to determine whether environmental variables, possibly acting through reproductive responses, contribute to the multiannual fluctuations of the montane vole, Microtus montanus.
Distribution and Significance of Mesozoic Vertebrate Trace Fossils in Dinosaur National Monument
Authors: Lockley Martin , Conrad Kelly , Paquette Marc , Farlow James
Published: July 2020

Search for new tracksites has now revealed a total of 25 localities in the older Mesozoic sedimentary rocks of Dinosaur National Monument (DNM). To date, the most productive units have proved to be the Late Triassic Chinle Group and the mainly Early Jurassic Glen Canyon Group in the western part of DNM. In addition several sites, that are an integral part of the overall paleontological picture, have been found just outside the boundaries of DNM. All these sites (and stratigraphic levels) add up to a total of about 45 tracksites in the DNM area. Chinle sites have now yielded dozens of trackways of theropod dinosaurs, ?prosauropod dinosaurs, mammal-like reptiles, ?phytosaurs, aetosaurs, lepidosaurs and tanystropheids, producing one of the most diverse Late Triassic track assemblages known anywhere. The ?prosauropod tracks are the first Late Triassic examples ever reported from the North American continent. The Lower Jurassic has also yielded theropod and prosauropod dinosaur tracks. These tracks are useful for correlation with other Early Mesozoic tracksites around the world and can be used to help construct a series of track zones (or Palichnostratigraphy) for the western United States. The discovery of prosauropod tracks (Pseudotetrasauropus) in the Chinle Group and in the lower part of Glen Canyon Group (Otozoum) points to a much wider distribution of prosauropod tracks in the western United States than previously supposed, and the need for a thorough study of these and similar track types. Further examination of the Jurassic Cannel Formation close to the DNM boundaries, reveals several tracksites that require further study.
Reclamation of Disturbed Lands in Glen Canyon National Recreation Area
Authors: McKell Cyrus
Published: July 2020

At Glen Canyon National Recreation Area (GCNRA) a number of disturbed sites require revegetation for aesthetic reasons and to maintain their natural appearace as part of the setting expected of a National Park or Recreation Area. Old road ways, decommissioned service areas, construction sites and bare areas characterize such sites. The purpose of thie project is (1) to conduct a literature review of revegetation reports pertinent to the climate and conditions of GCNRA and, (2) to extabllish two revegetation study areas at sites selected in consultation with NPS. Revegetation is necessary for functional reasons: 1) to prevent soil erosion and maintain or support the ecological balance of functioning ecosystems adjacent to the disturbed areas, and 2) to restore natural functions such as nutrient cycling, hydrology, soil stability and plant growth of the sites. Two of these sites were chosen as the location for revegetation tests.
Opportunistic Courtship Feeding in Sagebrush Crickets
Authors: Sakaluk Scott , Bangert Patricia , Swanson Lars , Eggert Anne-Katrin
Published: July 2020

The sagebrush cricket, Cyphoderris strepitans is one of only five extant species belonging to an ancient insect lineage, the Haglidae, believed to be ancestral to modern-day crickets and katydids (Orthoptera: Ensifera) (Morris and Gwynne 1978, Vickery 1989). C. strepitans occurs exclusively in mountainous areas of Wyoming and Colorado, where it is found primarily in high-altitude sagebrush meadow habitat. Adults become sexually active in May, shortly after snow melt, and remain active for the next 4-6 weeks. Pair formation is mediated through acoustic signaling by males, which functions to attract sexually receptive females (Snedden and Sakaluk 1992). Copulation is initiated when a receptive female climbs onto the dorsum of a male, at which time he attempts to transfer a spermatophore. During copulation, the female feeds on the male's fleshy hindwings and bodily fluids leaking from the wounds she inflicts, behavior which constitutes a form of courtship feeding (Dodson et al. 1983, Sakaluk et al. 1987, Morris et al. 1989, Sakaluk and Snedden 1990). At the same time, the female is secured by the male's abdominal pinching organ, a device known as a "gin trap" (Morris 1979). The gin trap of a male C. strepitans consists of two pairs of recurved spines, one pair directed anteriorally and the other posteriorally, located on the 10th and 8th tergites, respectively. The spines are brought together, pinching the female's abdomen, as the male's tergites are telescoped inward during his attempts to secure genitalic contact (Morris 1979). Although the gin trap clearly serves a reproductive role, its precise functional significance remains unknown; comparable reproductive structures are not known from any other family of the Orthoptera.
Surface Flow on Medano, Mosca, and Sand Creeks in Relation to Fault Zones and Water Tables
Authors: McCalpin James
Published: July 2020

This project seeks to determine the relation between surging surface flow and projected groundwater declines at the Great Sand Dunes National Monument. Surging flow in Medano Creek is a unique visitor attraction at the Monument, and is exhibited from April through July at easily accessible sites. Projected water table declines of up to 46 m due to an adjacent groundwater development scheme may increase infiltration rates in Monument creeks, thus leading to diminished or eliminated surge flow. This report covers the third 6-month period of the contract (May 15-Nov. 15, 1992).
Die-Off of Utah Juniper Natural Bridges National Monument
Authors: Weber Darrell , Nelson David
Published: July 2020

Utah junipers (Juniperus osterosperma (forr.)) are the dominant trees in the landscape of the southwestern states (35 million hectares). In Utah, the pinyon-juniper woodland represents 28.6% of the vegetation and are an important part of the aesthetic value of the Utah national parks. Over the past several years, extensive foliar damage has occurred to Utah juniper, yet little foliar damage has been observed in Natural Bridges National Monument, Canyonlands National Park, Arches National Park, Mesa Verde National Park and Colorado National Monument. The characteristic pattern is for the distal foliage to become chlorotic and die. Mortality progresses along twigs until whole branches or even the entire tree dies. The cause for the foliar damage is unknown. The loss of juniper trees in the national parks in southern Utah would have a dramatic ecological impact and would be an aesthetic blight in the parks. The purpose of this investigation is to determine the cause of the die-off of Utah junipers and suggest management options concerning the juniper die-off problem.
Impact of the 1988 Forest Fires on the Chemistry of Ground Water in Yellowstone National Park
Authors: Siders Mary , Runnells Donald
Published: July 2020

To determine the character and extent of possible changes in the chemistry of non-thermal ground waters in Yellowstone National Park that may have occurred as a result of the 1988 forest fires, a two-year program of sampling and analysis was begun in August, 1989. Samples from ground-water wells for which pre-fire chemical data could be obtained were selected for this study. The influx of ground water into surface waters (as baseflow) presents a possible pathway for ashÂ­ derived components to impact surface waters in the Park. Data from a recent study of a silicic, nonÂ­carbonate aquifer system suggest even small amounts of ground water can significantly affect the chemical balance of dilute lake waters (Kenoyer and Bowser 1992a, 1992b). Because of the dilute nature of nonÂ­thermal waters in the Park and the unknown effects that the fire may have had on the solute content of the ground water, this study was commissioned by the National Park Service (NPS) to examine possible fire-induced changes in the chemistry of shallow ground-waters in the Park. Results of this study may allow the NPS to anticipate any future impact upon the chemistry of surface waters in Yellowstone, in addition to identifying any deleterious effects of the fire on quality of non-thermal ground water in the Park. Due to the geochemical, biological and hydrological processes that modify infiltrating precipitation, it was anticipated that the impact of the forest fires on the chemistry of ground-water would be of lesser magnitude than the chemical and physical effects of fire on surface waters in the Park. Samples of soil water and ground water were collected and analyzed to evaluate the impact of the fires on the shallow, non thermal ground waters in the Park. For detailed study sites and methodology see Runnells and Siders (1992).
Taxonomy and Ecology of Ectomycorrhizal Macrofungi in the Vicinity of Grand Teton and Yellowstone National Parks
Authors: McKnight Kent , Moser Meinhard
Published: July 2020

The long-term objectives of this study are (1) to determine which species of higher fungi grow in forest, range, and pasturelands in and around Grand Teton and Yellowstone National Parks; (2) to gain a better understanding of the role of fungi in the ecosystem; (3) to prepare descriptions, keys, and illustrations for as many species as possible; and (4) to compare the fungal communities of this area with those of similar vegetation types in Europe. Fieldwork in the 1991 and 1993 seasons concentrated on the mushroom genus Cortinarius Fries, although other macrofungi are studied when permitted by time and availability of specimens.
Pollination Ecology and Breeding System of Delphinium Occidentale
Authors: Scogin Ron
Published: July 2020

Delphinium occidentale Nutt. (Ranunculaceae), the tall larkspur, occurs sporatically as isolated local populations in moist locations at lower and middle elevations of Grand Teton National Park. Individual plants of this species exhibit flowers which occur as one of three distinct color morphs and which occur mixed in the local populations. The three floral morphs are 1) plants exhibiting the most familiar, uniformly dark purple pigmented flower form, 2) plants exhibiting an all white, nonpigmented, albino form, and 3) plants whose flowers are intermediate in form between the extremes of 1) and 2), a semi-albino form which exhibits normally pigmented petals, but white, nonpigmented sepals. The occurrence of mixed, polymorphic populations of D. occidentale floral morphs can be rationalized by two alternative hypotheses: 1. A stable, balanced polymorphism exists among the three morphs. This polymorphism is actively maintained by selective pressures, probably on some aspect of the reproductive biology (perhaps pollination ecology) of the floral morphs, or 2. The distribution of polymorphs is merely a founder effect, reflecting the distribution of morphs present in the seed collection which initially established the colonizing population. The research undertaken during 1993 represents an effort to discriminate between these alternative explanations of flower color polymorphism in D. occidentale.
Effects of 1988 Fires on Ecology of Coyotes in Yellowstone National Park: Baseline Preceding Possible Wolf Recovery
Authors: Crabtree Robert
Published: July 2020

Sixty healthy adult coyote Canis latrans and 53, 8-12 week old pups captured at dens were radioÂ­ tagged in the Lamar Valley and Blacktail Plateau areas of the northern range of Yellowstone National Park. Adults range in age from 1 to 12 years and average nearly 3.3 years old. Territorial packs in both study areas are adjacent, non-overlapping, contiguous, and average 15 km2. Based on information from the last four winters and data collected from 1946 to 1949, territorial areas are traditional and have changed little in the last 45 years. We estimate that 85 to 90% of coyotes on the northern range belong to packs. A territorial group or pack during the winter consists of 2 alpha individuals, 2 or 3 beta adults, and 2 or 3 adult-sized pups (average pack size = 7). Fifteen marked coyotes have died since November of 1992. Initial density estimates are 1.4 coyotes per square mile. Preliminary scat analysis suggests that small mammals, especially voles, dominate the diet with ungulate remains becoming important in May through July (presumably elk calves) and late winter (mostly scavenging). Two graduate students have finished their data collection and another student is currently working on his last field season. More than 2500 hours of foraging observations were conducted from January 1991 through June 1993 resulting in data collection on more than 4400 predation attempts on small mammals. Eight hundred and fifty hours of den observations were completed during 1992 and 1993. Beta pack members were observed to bring food to pups and protect den sites from intruders. Coyote behavior and ungulate mortality data were collected on sixty-one carcasses found during the 1992-1993 winter. Five successful and 4 unsuccessful predations by coyotes on ungulates have been seen. Coyotes appear to impact ungulate numbers in 3 ways: predation on calves and fawns shortly after birth (up to 8 weeks), predation on short-yearlings and adults during winter, and indirect impact from harassment of other predators at ungulate-kills. Coyotes may be the major ungulate predator on the northern range due to their cooperative social and foraging behavior, ability to take advantage of vulnerable ungulates, and high population levels. Wolf extirpation has probably resulted in high coyote population densities and coyotes have, at least partially, slid into this vacant niche.
Spectral and Ecological Characterization of Yellowtsone Lodgepole Pine Cover Types
Authors: Jakubauskas Mark , Price Kevin
Published: July 2020

Accurate mapping of forest successional stages, or cover types, is critical for fire behavior prediction, animal habitat management, and preservation of biodiversity. Two research projects were based at the UW/NPS Research Station during the 1993 summer field season. The first project is a continuation of work begun in 1992, in which Landsat Thematic Mapper multispectral data are being used to identify the spectral reflectance characteristics of Yellowstone lodgepole pine cover types, and examine the relationships between spectral and biotic factors. A second project to characterize interception of photosynthetically active radiation (PAR) in lodgepole pine cover types using a portable integrating radiometer was initiated in 1993, but poor field conditions limited the number of samples that were taken.
Biogeography of Hanging Gardens of the Colorado Plateau
Authors: Stanton Nancy , Buskirk Steven , Fowler James , Hartman Ronald
Published: July 2020

The lush plant growth of hanging gardens attracted the attention of early explorers, botanists, and pioneers of the Colorado Plateau, a region dominated by bare rock and xeric vegetation. Hanging gardens are small, hydrophytic, herbaceous plant communities (Malanson 1980, Welsh and Toft 1975, Tuhy and MacMahon 1988, Welsh 1989a, Heil et al. 1991) on canyon walls in the entrenched drainage system of the Colorado Plateau. The microclimate of larger hanging gardens contrasts sharply with the surrounding high desert: water is abundant, soils are moist, and canyon walls offer periodic shade. This study was conducted to expand our current knowledge of hanging gardens with baseline data from a comparative ecological approach. Hanging gardens, in seven National Park Service units on the Colorado Plateau, were sampled for vascular plant diversity, distribution, abundance, levels of endemism, and biogeographic origin of endemic taxa. At the consumer level, insects, other arthropods, and small mammals were collected on selected hanging gardens to determine species diversity, distribution, and relative abundance. Since the publication of MacArthur and Wilson's (1967) Theory of Island Biogeography, many attempts have been made to use the positive correlation between island size and species richness to conserve species diversity in fragmented and natural terrestrial habitat islands (see Shafer 1990 for a review). An initial impetus for this study was the island-like appearance of hanging garden habitats. Theoretical work on the species richnessÂ­area relationship have prompted many empirical studies testing support for one of three alternate hypotheses: (1) MacArthur and Wilson's (1963, 1967) equilibrium hypothesis, (2) Williams' (1943) (and later Connor and McCoy 1979) habitat diversity hypothesis, and (3) Arrhenius' (1921) passive sampling hypothesis. This study describes the hanging-garden vascular plant species-area relationship and tests support for these alternate hypotheses. The immigration and extinction curves that MacArthur and Wilson (1967) incorporated into their equilibrium hypothesis were recently put into a spatially structured, multispecies metapopulation model (Gotelli 1991) as an alternative to an original metapopulation model and Hanski's (1982) coreÂ­satellite species metapopulation model. Gotelli (1991) then introduced a fourth metapopulation model which incorporated both propagule rain and the rescue effect. The last model, as well as the original metapopulation model, and the equilibrium hypothesis (MacArthur and Wilson 1967) based model, predict a unimodal distribution on species occurrence histograms (Gotelli 1991). The coreÂ­satellite model predicts a bimodal distribution on species-occurrence histograms. This study was primarily designed to collect distribution and abundance data for hanging-garden plant and bee species as a test of the core-satellite prediction.
The Roosting Ecology of the Silver-Haired Bat Lasionycteris noctivagans in the Black Hills of South Dakota
Authors: Mattson Todd , Stanton Nancy , Buskirk Steven
Published: July 2020

The silver-haired bat Lasionycteris noctivagans occurs widely across North America (Kunz 1982a) at highly variable densities (Barbour and Davis 1969). Still, little is known of its ecology and behavior, especially of its summer roosting habits (Kunz 1982a). Summer roost sites have been alledged to be mostly in trees, but few reliable records are available (Kunz 1982a). Barclay et al. (1988) searched trees in Manitoba and found silverÂ­haired bats roosting under folds of loose bark during the migration period. Likewise, Parsons et al. (1986) and Novakowski (1956) each reported finding a small maternity colony of silver-haired bats in hollow trees in Canada. Studies in the northwestern United States have suggested that silver-haired bats occur more frequently in late-successional forest dominated by trees over 200 yr old than in early seres (Perkins and Cross 1988, Thomas 1988). This association has been attributed to the presence of high concentrations of standing dead trees, some of which have exfoliated bark, cracks in the wood, and cavities excavated by birds sites that may be preferred by bats for roosting (Perkins and Cross 1988, Thomas 1988). To better understand roost selection and habitat requirements of silver-haired bats, we investigated the roosting ecology of this species in the Black Hills of South Dakota.
Survey of Precise Leveling Array Grand Teton National Park
Authors: Sylvester Arthur , Smith Robert
Published: July 2020

Fifteen permanent bench marks were established east and south of the existing 22 km-long line of 50 bench marks across the Teton normal fault in Grand Teton National Park to compare height changes of Jackson Hole relative to the Teton Range on the west and Shadow Mountain on the east. The new bench marks, together with three other agency bench marks and three temporary bench marks, constitute a 7. 8 km-long extension to the existing line tied to the old line at bench mark GT01. The new bench marks were precisely leveled between 30 August and 5 September 1994. Misclosure of the double-run survey was 0.86 mm, thus the precision of the total survey is 1 part in 10 million. If the misclosure is simply spread equally among the (n-1) bench marks, then the probable error associated with the relative height of a single bench mark is effectively zero.
Seed Bank Viability in Jackson Lake Grand Teton National Park, Wyoming
Authors: Brewer Carol , Brown Melissa
Published: July 2020

The submersed plant community in Jackson Lake is an important resource in Grand Teton National Park for both terrestrial and aquatic organisms. Since the early 1900's, Jackson Lake has been influenced by a series of drawdowns of varying magnitude that influenced the composition and extent of the macrophyte community in the littoral zone. While many physical conditions have been linked to macrophyte growth and distribution in lakes (e.g., light, sediments, nutrients, slope) recent work suggests that the magnitude and timing of water level fluctuations may be the most important factor regulating macrophyte community processes at shallower depths in regulated reservoirs (Brewer and Parker 1990; Gasith and Gafny 1990; Rerslett 1984, 1987). Because of the importance of the aquatic plant community in Jackson Lake as a food source and shelter for wildlife (waterfowl, fish,invertebrates, mammals), the factors affecting growth and recovery after disturbance have received periodic attention since the late 1960's (Hayden 1969; Brewer 1986; Brewer and Rerslett 1987; Brewer and Parker 1990; Brewer and Thompson 1994). Initial work on plant community dynamics in Jackson Lake has shown that the aquatic plant community in Jackson Lake has been exposed to a varied disturbance regime that has impacted recolonization, species diversity and peak biomass development. Because the extent of littoral habitat suitable for macrophyte growth in regulated lakes depends on the timing and magnitude of seasonal and long-term drawdowns, drawdown schedules and resulting fluctuating water levels may be selecting for a plant community characterized by low diversity and patchy distribution. Peak production under such conditions in Jackson Lake tends to be shifted into deeper waters (Brewer and Parker 1990; Brewer and Thompson 1994). Furthermore, clonal, weedy species with reduced value for wildlife (e.g., Elodea canadensis, Myriophyllum sibericum) have enhanced opportunities for dispersal under such a disturbance regime and are favored when maximum drawdown occurs during the period of peak standing crop. While historical records describing changing patterns of macrophyte distribution are available for Jackson Lake, few data are available to evaluate the influence of fluctuating water levels on the seed bed, and the potential for recruitment after disturbance from this source. The objective for our work was to establish protocols and collect preliminary data on the potential for recruiting macrophytes from the littoral seed bank by measuring germination of seeds from lake sediments.
Post-Copulatory Female Choice in Sagebrush Crickets
Authors: Johnson J. , Ivy Tracie , Eggert Anne-Katrin , Sakaluk Scott
Published: July 2020

Male sagebrush crickets (Cyphoderris strepitans) permit females to engage in an unusual form of sexual cannibalism during copulation: females feed on males' fleshy hind wings and ingest haemolymph oozing from the wounds they inflict. These wounds are not fatal, and normally only a portion of the hind wings are eaten at any one mating, so that mated males are not precluded from mating again. However, non-virgin males have fewer resources to offer females than do virgin males, such that females should be selected to preferentially mate with virgin males. Because previous work has indicated a lack of pre-copulatory female choice, we tested the hypothesis that females accept matings with non-virgin males, but discriminate against them afterwards by re-mating sooner than they otherwise would after matings with virgin males. If the last male to copulate with a female prior to egg laying does in fact sire the majority of her offspring, then such post-copulatory behavior would constitute a form of female choice. To test this, we experimentally manipulated both female diet (high protein vs. low protein), and the female's ability to feed on males' wings during mating. We predicted that females prevented from wing feeding and held on a low protein diet would remate sooner than females allowed to wing feed and held on a high protein diet. We measured the amount of time males spent calling in mating trials, and the time to first and second mountings and matings for each female. Our results reveal an effect of wing treatment on the time to first mating. Low protein females mated with winged males significantly more readily than they did with deÂ­winged males. Female diet also had a significant effect on the time to first mounting. Females fed only lettuce (low protein) mounted males sooner than females provisioned with apple and a bee pollen supplement (high protein), indicating that a female's overall nutrient intake may determine her propensity to mate regardless of the mating status of the male she is paired with. No effect of diet or wing treatment was found for time to second mounting or mating.
Parasites of Small Mammals in Grand Teton National Park: Babesia and Hepatozoon
Authors: Watkins Raychel , Moshier Suzanne , Pinter Aelita
Published: July 2020

Babesia microti, a parasitic protozoan, is endemic in the Microtus montanus of Grand Teton National Park. It is transmitted by the tick Ixodes eastoni and reproduces in the erythrocytes of its vole host. A second protozoan parasite, Hepatozoon sp., which is widespread in small mammals in Europe, is also found in reptiles throughout the world. The record of Hepatozoon in North American small mammals is not extensive. Hepatozoon, unlike Babesia, may be a two-host or a three-host parasite. Also unlike Babesia, for which the intermediate host is always a tick, the intermediate host of Hepatozoon may be a tick, a mite, a flea, or a mosquito. The method of transmission by the vector also differs in the two parasites. Babesia is transmitted in the tick's saliva when it bites, whereas Hepatozoon infection requires the vertebrate host to ingest a vector. In our 1996 studies, we sought more data on these two parasites. The objectives for 1996 focused on Hepatozoon: to sample specific populations of M. montanus, in which we have previously documented Hepatozoon infections; to determine whether differences exist in the infection rates at different study sites in the park; and to search for any additional vectors of Hepatozoon sp. infections in M. montanus by examining ectoparasites. These studies contributed to our long-term objectives of documenting the effects and cost of parasitism on M. montanus populations.
Trophic State Evaluation of Jackson Lake in Grand Teton National Park
Authors: Miller Woodruff
Published: July 2020

This study is the continuation of an evaluation of the trophic state of lakes located in Grand Teton National Park, Wyoming. The original 1995 study was motivated by concern that the water quality of the lakes within the Park may be declining due to increased human usage over the past several years. A trophic state evaluation, featuring nutrient and chlorophyll-a analyses, was chosen because it is believed to be a sound indicator of the lakes' overall water quality. In this 1996 study, a thorough evaluation was made of Jackson Lake. This summary is taken from the complete 100 page report which is available from Woodruff Miller at Brigham Young University or Hank Harlow at the University of Wyoming. In most cases water samples were taken four times during the summer of 1996, in June, July, August, and October. Jackson Lake was sampled at eight different locations on thesurface and at depths near the bottom. The lake inlet and outlet were also sampled four times. Jackson Lake was sampled from a motor boat which also provided a means to measure the lake transparency and depth. The chlorophyll-a and nutrient concentrations were analyzed by the Utah State Health Department, Division of Laboratory Services. Jackson Lake was evaluated using the models of Carlson, Vollenweider, and LarsenÂ­Mercier. The nature of the Larsen-Mercier and Vollenweider models, based on system inflow and outflow data, is such that they yield one trophic state assessment of the lake per inflow and outflow sample set. The Carlson Trophic State Indices (TSI), on the other hand, are based on in situ properties of the water at any point in the lake. Consequently, while there are four Vollenweider and four Larsen-Mercier evaluations for Jackson Lake, individual Carlson evaluations were made for the eight sample sites around the lake at the surface and at depth, and an evaluation for the lake as a whole was constructed using averages taken from the site evaluations. This allowed us to examine the relative water quality of different portions of the lake at different time periods.
Climatic Factors, Reproductive Success and Population Dynamics in the Montane Vole, Microtus montanus
Authors: Pinter Aelita
Published: July 2020

Multiannual fluctuations ("cycles") in population density of small rodents doubtless result from the interaction of a multitude of factors, as evidenced by the variety of hypotheses proposed to explain the phenomenon (for reviews see Finerty 1980, Taitt and Krebs 1985). However, the inability of these hypotheses - alone or in combination - to explain the causality of cycles rests in no small measure with the fact that long-term studies of the phenomenon are notoriously uncommon. The objectives of this project are to continue a long-term study of the population dynamics of the montane vole, Microtus montanus, in Grand Teton National Park. On the basis of earlier observations (Pinter 1986, 1988) particular emphasis will be placed on how environmental variables, possibly acting through reproductive responses, contribute to the population density cycles of these rodents.
Virgin Male Mating Advantage in Sagebrush Crickets: No Role for an Acoustically-Mediated Female Preference
Authors: Sakaluk Scott , Brady Pamela , Ivy Tracie , Sakaluk Marion , Schaus Jennifer
Published: July 2020

The sagebrush cricket, Cyphoderris strepitans, is one of only five extant species belonging to an obscure orthopteran lineage, the Haglidae, closely related to the true crickets (Gryllidae) and katydids (Tettigoniidae) (Morris & Gwynne 1978). C. strepitans occurs exclusively in mountainous areas of the western United States, where it is found primarily in high-altitude sagebrush meadow habitat. Adults become sexually active in late spring, shortly after snow melt, and remain active for the following 4-6 weeks. The acoustic signals produced by males function to attract females (Snedden & Irazuzta 1994), thereby enhancing male mating opportunities (Snedden & Sakaluk 1992). Copulation is initiated when a receptive female climbs onto the dorsum of a male, at which time he attempts to transfer a spermatophore. During copulation, the female feeds on the male's fleshy hind wings and bodily fluids leaking from the wounds she inflicts. Previous field studies involving the markÂ­recapture of a large number of males have shown that once a male has mated, his probability of obtaining an additional copulation is reduced relative to that of a virgin male securing his first mating (Morris et al. 1989). One explanation for the virgin-male mating advantage is that non-virgin males, having lost a substantial portion of their energy reserves through sexual cannibalism by females and the transfer of a large spermatophore, may be unable to sustain the costly acoustical signaling activity required to attract additional females. In support of the "male fatigue" hypothesis, electronic assays of male signaling behavior have shown that virgin male C. strepitans call for significantly longer durations than recently mated males (Sakaluk et al. 1987; Sakaluk & Snedden 1990).