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Remembering The Days Of Old: Data Exploration And Simple Statistics, Christopher N. Jacques Dec 2015

Remembering The Days Of Old: Data Exploration And Simple Statistics, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! By the time you read this editorial, most of you will probably be enjoying spectacular seasonal changes in the outdoors this autumn and a hint of winter in the air (for those of us in the northern Great Plains region). I write this editorial during my favorite time of year, deer hunting in the Midwest. Temperatures are finally start- ing to resemble the fall and the Christmas Holiday season is just around the corner. Much like my children have images of Santa dancing in their heads on Christmas Eve, each fall I replay images of a trophy …


Notes: Woodpecker Forage Availability In Habi- Tat Disturbances Of The Black Hills, Brian E. Dickerson, Angie K. Ambourn, Mark A. Rumble, Kurt K. Allen, Chad P. Lehman Dec 2015

Notes: Woodpecker Forage Availability In Habi- Tat Disturbances Of The Black Hills, Brian E. Dickerson, Angie K. Ambourn, Mark A. Rumble, Kurt K. Allen, Chad P. Lehman

The Prairie Naturalist

Habitat disturbance events are critical to ecological systems in which some bird species have become specialized. The vegetation community, reduced competition, ability to avoid predators, nest-site characteristics, and forage opportunities within a disturbed ecosystem are all aspects that make it desirable for selection by particular species (Svärdson 1949, Cody 1981, Martin 1998). Specifically, avian species rely on the forest conditions created by fire, insects, and disease (Brawn et al. 2001, Hunter et al. 2001, Devictor et al. 2008). In the Black Hills National Forest (BHNF) of South Dakota,two major types of natural disturbances include wildfires and mountain pine beetle (Dendroctonus …


Estimating Herbaceous Biomass Of Grassland Vegetation Using The Reference Unit Method, Eric D. Boyda, Jack L. Bulter, Lan Xu Dec 2015

Estimating Herbaceous Biomass Of Grassland Vegetation Using The Reference Unit Method, Eric D. Boyda, Jack L. Bulter, Lan Xu

The Prairie Naturalist

Aboveground net primary production provides valuable information on wildlife habitat, fire fuel loads, and forage availability. Aboveground net primary production in herbaceous plant communities is typically measured by clipping aboveground biomass. However, the high costs associated with physically harvesting plant biomass may prevent collecting sufficient data to account for natural spatial and temporal variability of vegetation at a landscape scale. Various double-sampling techniques have been developed to increase sample size while reducing cost. We applied a biomass estimation technique previously developed for estimating shrub biomass using representative samples or “reference units” to estimate herbaceous grassland biomass. Our reference units consisted …


Sage-Grouse Nests In An Active Conifer Mastication Site, Charles P. Sandford, David K. Dahlgren, Terry A. Messmer Dec 2015

Sage-Grouse Nests In An Active Conifer Mastication Site, Charles P. Sandford, David K. Dahlgren, Terry A. Messmer

The Prairie Naturalist

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) have experienced long-term range-wide population declines and now may occupy less than 50% of their historic range (Schroeder et al. 2004). Conifer encroachment into sagebrush (Artemisia spp.) habitat was identified as a major conservation threat by the United States Fish and Wildlife Service (USFWS) as the agency reviewed the listing status of the species for possible protection under the Endangered Species Act of 1973 (USFWS 2013).

Conifer encroachment into sagebrush habitats negatively impacts sage-grouse at landscape scales (Doherty et al. 2008, Casazza et al. 2011, Baruch-Mordo et al. 2013). Sage-grouse will utilize …


North Shore: A Natural History Of Minnesota’S Superior Coast, Janet R. Keough Dec 2015

North Shore: A Natural History Of Minnesota’S Superior Coast, Janet R. Keough

The Prairie Naturalist

Many readers of The Prairie Naturalist have lived along or visited Lake Superior’s coast. Like me, you have probably wondered about the geology and history of this beautiful and dramatic feature of northeastern Minnesota. Chel Anderson and Adelheid Fischer have written an accessible book that comprehensively describes the history and geology of the coast, surrounding highlands, and Lake Superior itself. In addition, the authors have provided fascinating subchapters on some of the most interesting species that are key elements of the region.

This rather large but beautiful book is arranged in five major chapters that cover the dominant geological units …


Distribution And Occurrence Of Bat Species In North Dakota, Josiah J. Nelson, Paul R. Barnhart, Erin H. Gillam Dec 2015

Distribution And Occurrence Of Bat Species In North Dakota, Josiah J. Nelson, Paul R. Barnhart, Erin H. Gillam

The Prairie Naturalist

Prior to 2009, a detailed survey of occurrence and distribution of bats in North Dakota had not been conducted. Localized surveys, occurrence reports, and museum specimens provided the only records of bats in the state. Ongoing habitat loss, exploitation of natural resources, and the impending spread of white-nose syndrome to the western United States are major threats to bat populations of the region. The objective of this study was to document presence and distributions of bat species resident in North Dakota. From 2009 to 2012, multiple mist-netting and acoustic surveys were conducted to document species presence across North Dakota. A …


Use Of Hppd-Inhibiting Herbicides For Control Of Common Weeds In Arkansas And Current Status Of Herbicide-Resistance Among Echinochloa Populations In Arkansas, Clay Starkey Dec 2015

Use Of Hppd-Inhibiting Herbicides For Control Of Common Weeds In Arkansas And Current Status Of Herbicide-Resistance Among Echinochloa Populations In Arkansas, Clay Starkey

Graduate Theses and Dissertations

Herbicide-resistant weeds in Arkansas cause problems for growers. Up-to-date information and new technologies can help plan mitigation strategies to slow resistant weeds. The objectives of this research were to provide a ‘snapshot’ of herbicide-resistant Echinochloa spp. in rice producing counties, determine how much resistance has spread across the state, and understand the effectiveness of 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides for control of glyphosate-resistant (GR) Palmer amaranth relative to commercial standards currently labeled in soybean. To assess the prevalence of Echinochloa spp. resistance, 82 samples were collected from 23 rice producing counties in 2010. The samples were tested for resistance to commonly …


Variation Between Peripheral And Center Achene Morphology And Attributes Of Achene Germination In The Invasive Species, Centaurea Melitensis, Kandee Bain Dec 2015

Variation Between Peripheral And Center Achene Morphology And Attributes Of Achene Germination In The Invasive Species, Centaurea Melitensis, Kandee Bain

Electronic Theses, Projects, and Dissertations

Invasive species are often successful and problematic because of their ability to persist in disturbed and undisturbed environments despite weed management practices. Understanding reproduction and dispersal strategies in these species can aid in developing management approaches to help control their spread. Centaurea melitensis, a nonnative invasive with European origins, is found in disturbed areas of southern California. It produces three different types of flower heads that develop at different times and at different locations on the plant during the growing season. The chasmogamous (CH) flower heads are located at the top of the plant, the initial cleistogamous (iCL) heads …


Predicting Invasive Range Of Eucalyptus Globulus In California, Anthony J. Lopez Dec 2015

Predicting Invasive Range Of Eucalyptus Globulus In California, Anthony J. Lopez

Master's Theses

Eucalyptus globulus is the subject of intense debate in California. Its invasive potential, aggressive growth, reproductive biology, and association with fire make the prediction of spread important in California. Two modeling simulations, Climex and Maxent, will illustrate the distribution and potential growth range of E. globulus in California based on climate and presence. Modeling the potential range of growth will predict invasive spread. The anticipated result is the continued spread of E. globulus in coastal regions with adequate moisture and suitable climate. Predicting the range of E. globulus in California dictates management strategy and is key for preventing further introduction, …


Canola: A Modern Crop For A Modern Era, Kenneth J. Roché Nov 2015

Canola: A Modern Crop For A Modern Era, Kenneth J. Roché

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska-Lincoln Doctor of Plant Health program is a professional doctorate program with a comprehensive approach to plants and agriculture. The program emphasizes a broad interdisciplinary education across all plant-related disciplines, practical learning, research, and experience through internships. For my final required internship, I worked as a senior agricultural research intern with Research Designed for Agriculture (RD4AG) in Montana. RD4AG is a contract research organization based in Yuma, AZ with over thirty-years of experience. During my three month internship at RD4AG in Montana, a large portion of my responsibilities centered on managing regulated canola trials that were undertaken …


Enhancing The Effectiveness Of Biological Control Programs Of Invasive Species By Utilizing An Integrated Pest Management Approach, Invasive Species Advisory Committee Oct 2015

Enhancing The Effectiveness Of Biological Control Programs Of Invasive Species By Utilizing An Integrated Pest Management Approach, Invasive Species Advisory Committee

National Invasive Species Council

Conclusion

Biological control has been shown on many occasions to be the most cost-effective invasive species management tool available. However, integrating biological control projects with the full breadth of other integrated pest management (IPM) tools, expanding post-re- lease monitoring to maximize efficacy, adaptive management, and incorporating new and innovative ecological, and genetic technologies may provide private and public land managers greater opportunities for long-term success in suppression of established invasive species.


Pengaruh Keberadaan Gulma (Ageratum Conyzoides Dan Boreria Alata) Terhadap Pertumbuhan Dan Hasil Tiga Ukuran Varietas Kedelai (Glycine Max L. Merr) Pada Percobaan Pot Bertingkat, Abdul Karim Kilkoda, Tati Nurmala, Dedi Widayat Oct 2015

Pengaruh Keberadaan Gulma (Ageratum Conyzoides Dan Boreria Alata) Terhadap Pertumbuhan Dan Hasil Tiga Ukuran Varietas Kedelai (Glycine Max L. Merr) Pada Percobaan Pot Bertingkat, Abdul Karim Kilkoda, Tati Nurmala, Dedi Widayat

Jurnal Kultivasi

Percobaan dilaksanakan di rumah kaca Fakultas Pertanian Universitas Padjadjaran, Jati-nangor, Kabupaten Sumedang, Jawa Barat. Tujuan dari penelitian ini adalah untuk menguji eksudat akar yang terdapat pada gulma Ageratum conyzoides dan Borreria alata terhadap pertumbuhan dan hasil tanaman kedelai. Percobaan dilakukan mulai dari bulan Oktober 2014 sampai dengan bulan Desember 2014 dengan menggunakan rancangan acak kelompok pola faktorial. Faktor perlakuan pertama adalah jenis gulma terdiri dari 3 taraf antara lain gulma A. Conyzoides, gulma B. alata dan tanpa gulma (kontrol). Perlakuan kedua adalah ukuran benih varietas kedelai yang terdiri dari 3 taraf. Total kombinasi perlakuan adalah 9 kombinasi perlakuan, dengan 3 …


Pengaruh Dosis Herbisida Glifosat Terhadap Gulma, Pertumbuhan, Dan Hasil Tiga Kultivar Kedelai (Glycine Max (L.) Pada Sistem Tanpa Olah Tanah (Tot), Dedi Widayat, R. Ganilda Yustisiyanika Oct 2015

Pengaruh Dosis Herbisida Glifosat Terhadap Gulma, Pertumbuhan, Dan Hasil Tiga Kultivar Kedelai (Glycine Max (L.) Pada Sistem Tanpa Olah Tanah (Tot), Dedi Widayat, R. Ganilda Yustisiyanika

Jurnal Kultivasi

Penelitian ini bertujuan untuk mengetahui pengaruh interaksi antara dosis herbisida Glifosat dan kultivar kedelai terhadap gulma, pertum-buhan, dan hasil tanaman kedelai. Percobaan dilakukan di Kebun Percobaan Saung Meeting Ciparanje Universitas Padjadjaran Jatinangor, Kabupaten Sumedang. Rancangan percobaan yang digunakan adalah rancangan acak kelompok pola faktorial yang terdiri dari dua faktor dan diulang 3 kali. Faktor yang pertama adalah kultivar kedelai yang tediri dari tiga yaitu kultivar Tidar, Burangrang, dan Slamet. Faktor yang kedua dosis herbisida glifosat yang terdiri dari 3 taraf yaitu 1,5l/ha, 3l/ha, dan 4,5l/ha. Kombinasi perlakuan kultivar dan dosis herbisida glifosat tidak memberikan pengaruh interaksi terhadap bobot kering gulma …


Assessing Multiple-Herbicide Resistance In A 2,4-D Resistant Waterhemp (Amaranthus Tuberculatus) Biotype From Nebraska: Student Research, Roberto Crespo Oct 2015

Assessing Multiple-Herbicide Resistance In A 2,4-D Resistant Waterhemp (Amaranthus Tuberculatus) Biotype From Nebraska: Student Research, Roberto Crespo

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

A waterhemp biotype was recently reported resistant to 2,4-D in Nebraska. In addition to the repeated use of 2,4-D, atrazine and imazathapyr were reported to be frequently used to control broadleaf weeds. Greenhouse experiments were conducted to confirm 2,4-D resistance and test for resistance to growth regulator herbicides and other herbicide modes-of-action (MoA). A single dose-response experiment showed reduced sensitivity in all three waterhemp biotypes to atrazine, imazethapyr and lactofen; therefore, they were generally considered resistant to those three herbicide MoA. None of the biotypes contained the Ser264 target-site mutation. Since the ametryn dose-response experiment resulted in all susceptible biotypes, …


When An Invasive Plant Fails To Invade, Stephen L. Young Oct 2015

When An Invasive Plant Fails To Invade, Stephen L. Young

West Central Research and Extension Center, North Platte

In 2012, much of the US Midwest was gripped in one of the most severe droughts on record. While conducting experimental fieldwork at a site in Nebraska during June of that year, I noticed a single musk thistle (Carduus nutans; Figure 1) that appeared to be in the bolt or early flowering stage, which is typical for the species at that time. Here, however, two things were unusual: this plant was less than 1 meter tall (with adequate moisture and light, musk thistle typically grows to heights of 1–2.5 meters before flowering), and was only 3 months old (the bolt …


The Invasive American Weed Parthenium Hysterophorus Can Negatively Impact Malaria Control In Africa, Vincent O. Nyasembe, Xavier Cheseto, Fatma Kaplan, Woodbridge A. Foster, Peter E.A. Teal, James H. Tumlinson, Christian Borgemeister, Baldwyn Torto Sep 2015

The Invasive American Weed Parthenium Hysterophorus Can Negatively Impact Malaria Control In Africa, Vincent O. Nyasembe, Xavier Cheseto, Fatma Kaplan, Woodbridge A. Foster, Peter E.A. Teal, James H. Tumlinson, Christian Borgemeister, Baldwyn Torto

All Peer-Reviewed Publications

The direct negative effects of invasive plant species on agriculture and biodiversity are well known, but their indirect effects on human health, and particularly their interactions with disease-transmitting vectors, remains poorly explored. This study sought to investigate the impact of the invasive Neotropical weed Parthenium hysterophorus and its toxins on the survival and energy reserves of the malaria vector Anopheles gambiae. In this study, we compared the fitness of An. gambiae fed on three differentially attractive mosquito host plants and their major toxins; the highly aggressive invasive Neotropical weed Parthenium hysterophorus (Asteraceae) in East Africa and two other adapted weeds, …


Prescribed Fire Monitoring Report, Tallgrass Prairie National Preserve 2014 (Iqcs Fire Number 285382, 285383, 266782, 285677), Sherry A. Leis, Sarah E. Hinman Sep 2015

Prescribed Fire Monitoring Report, Tallgrass Prairie National Preserve 2014 (Iqcs Fire Number 285382, 285383, 266782, 285677), Sherry A. Leis, Sarah E. Hinman

United States National Park Service: Publications

Introduction

In 2014, the preserve’s federal and NGO partners conducted prescribed fires during March, April, and October that encompassed 8129.8 acres of Tallgrass Prairie National Preserve (TAPR). This was a unique burn year in that prescribed burns occurred in the spring, the traditional burn season, and the fall. Fall burns were conducted to support needed archaeological surveys as part of the environmental compliance for a symphony event scheduled for June 2015 at the preserve. Burns at TAPR were coordinated with local US Fish and Wildlife Service (USFWS), The Nature Conservancy (TNC), and various units of the National Park Service.

Burns …


Plant Community Associations Of Two Invasive Thistles, Emily S.J. Rauschert, Katriona Shea, Sarah Goslee Jun 2015

Plant Community Associations Of Two Invasive Thistles, Emily S.J. Rauschert, Katriona Shea, Sarah Goslee

Biological, Geological, and Environmental Faculty Publications

In order to combat the growing problems associated with biological invasions, many researchers have focused on identifying which communities are most vulnerable to invasion by exotic species. However, once established, invasive species can significantly change the composition of the communities that they invade. The first step to disentangling the direction of causality is to discern whether a relationship with other vegetation exists at all. Carduus nutans and C. acanthoides are similar invasive thistles, which have caused substantial economic damage worldwide. We assessed the associations between the thistles and the standing flora in four sites in central Pennsylvania in which they …


Vascular Plants Of The Forest River Bi- Ology Station, North Dakota, Alexey Shipunov, Kathryn A. Yurkonis, John C. La Duke, Vera L. Facey Jun 2015

Vascular Plants Of The Forest River Bi- Ology Station, North Dakota, Alexey Shipunov, Kathryn A. Yurkonis, John C. La Duke, Vera L. Facey

The Prairie Naturalist

During summer 2013 we completed a listing of the plant species of the joint University of North Dakota (UND) Forest River Biology Station and North Dakota Game and Fish Department Wildlife Management Area (FRBS).The FRBS is a 65 ha tract of land that encompasses the south half of the SW 1⁄4 of section 11 (acquired by UND in 1952) and the north half of the NW 1⁄4 of section 14 (acquired by UND in 1954) in Inkster Township (T154N, R55W). The two parcels are bisected by the Forest River, a tributary of the Red River of the North. The area …


Food Habits Of Fall-Collected Age-0 Walleyes In Eastern South Dakota Gla- Cial Lakes, Benjamin J. Schall, Matthew J. Phayvanh, Jeffrey D. Grote, Daniel J. Dembkowski, Melissa R. Wuellner Jun 2015

Food Habits Of Fall-Collected Age-0 Walleyes In Eastern South Dakota Gla- Cial Lakes, Benjamin J. Schall, Matthew J. Phayvanh, Jeffrey D. Grote, Daniel J. Dembkowski, Melissa R. Wuellner

The Prairie Naturalist

Food habits of age-0 fishes can influence their growth and survival prior to the first winter (Hoxmeier et al. 2006, Shoup and Wahl 2011). Ontogenetic diet shifts in juvenile piscivorous fishes result in a transition in consumption from zooplankton to macroinvertebrates and eventually fish throughout development (Mittelbach and Persson 1998). Certain food items may be more energetically beneficial to fishes than others as consumption of prey fishes may lead to faster growth rates of predators, decreased overwinter starvation, avoidance of competition, and reduced predation risk (Werner and Gilliam 1984). By the time age-0 walleyes (Sander vitreus) have reached lengths of …


Improving Communication Through Writing, Christopher N. Jacques Jun 2015

Improving Communication Through Writing, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! By the time you read this editorial, most of us will be enjoying the summer vacation and all that the Great Plains has to offer. Warmer temperatures, increasing day length, and time in the field are a welcomed change from the seemingly endless grip of “old man” winter (for those of us in the northern Great Plains). Of course, believing that anyone could truly enjoy the clouds of tormenting, biting insects and high humidity across the Great Plains is hard to imagine, in my opinion. There are plenty of summer activities for the outdoor enthusiasts among us, …


Bot Fly Infestation Of Thirteen-Lined Ground Squirrels In Colorado Shortgrass Steppe, Kim Conway, Paul Stapp Jun 2015

Bot Fly Infestation Of Thirteen-Lined Ground Squirrels In Colorado Shortgrass Steppe, Kim Conway, Paul Stapp

The Prairie Naturalist

We studied prevalence of bot fly infestation of thirteen-lined ground squirrels (Ictidomys tridecemlineatus) trapped during 13 years of population monitoring in shrub and grassland habitats in northern Colorado. We also investigated effects of prescribed burning, a common habitat management practice in grasslands, on bot fly prevalence. Infested squirrels were rarely located on shrub sites and during spring (May–Jun) trapping. Across all summers, mean prevalence in grasslands was 7.9% (range: 2.1–23.8%), with years of highest prevalence corresponding to years when the fewest hosts were captured in spring. Infested squirrels had from one to seven warbles, with 46.7% having only one warble. …


Habitat-Related Differences In Necroph- Ilous Species Composition: Implications For Resource Competition, Adrienne L. Conley, Elisabeth K. Jorde, Rachel E. Jorde, Lauren K. Yares, Kenzie K. Lee, Carrie L. Hall, Daniel R. Howard Jun 2015

Habitat-Related Differences In Necroph- Ilous Species Composition: Implications For Resource Competition, Adrienne L. Conley, Elisabeth K. Jorde, Rachel E. Jorde, Lauren K. Yares, Kenzie K. Lee, Carrie L. Hall, Daniel R. Howard

The Prairie Naturalist

Competition for resources is one of the most important selective factors influencing the expression of life history traits in both plants and animals (Darwin 1859). In grasslands, competition for resources such as nutrients, water, and space often is constrained by stochastic processes (Axelrod 1985). Disturbance factors such as fire, grazing by large herbivores, and fluctuating climatic conditions tend to alter the structure and magnitude of competition for limited resources among grassland communities more frequently than in other ecosystems (Snaydon 1987, van der Maarel 1993). Vertebrate carrion is one important resource used by both plants and animals in grasslands, providing a …


Comparison Of Two Trap Net Designs For Sampling Muskellunge, Brian G. Blackwell, Todd M. Kaufman, Tyrel S. Moos, David O. Lucchesi Jun 2015

Comparison Of Two Trap Net Designs For Sampling Muskellunge, Brian G. Blackwell, Todd M. Kaufman, Tyrel S. Moos, David O. Lucchesi

The Prairie Naturalist

Sampling adequate numbers of muskellunge (Esox masquinongy) is necessary to evaluate stocking success and to collect information on various population metrics (e.g., growth, condition, relative abundance). However, muskellunge are often difficult to sample with standard fish sampling gears. We collected muskellunge in trap nets of two different designs (large trap nets [1.5-m × 1.8-m frames, 1.5-m diameter hoops, double throated, single 1.5-m × 30.5-m lead and 19-mm knotless mesh] and small trap nets [0.9-m × 1.5-m frames, 0.9-m diameter hoops, single throat, single 0.9-m × 15.2-m lead and 19-mm knotted mesh]. We also estimated abundance of muskellunge (>600 mm …


Notes: Are Land-Use Changes Reflected In Diets Of Mourning Doves (Zenaida Macroura) In Eastern South Dakota, Joshua B. Smith, Troy W. Grovenburg, Matthew A. Perrion, Jason M. Augspurger, Trevor W. Bultje, Anna M. Robinson, Brandi L. Crider, Datta Shubham, Jonathan A. Jenks Jun 2015

Notes: Are Land-Use Changes Reflected In Diets Of Mourning Doves (Zenaida Macroura) In Eastern South Dakota, Joshua B. Smith, Troy W. Grovenburg, Matthew A. Perrion, Jason M. Augspurger, Trevor W. Bultje, Anna M. Robinson, Brandi L. Crider, Datta Shubham, Jonathan A. Jenks

The Prairie Naturalist

Food habits of the mourning dove (Zenaida macroura) have been extensively studied in the southern United States (McClure 1943, Korschgen 1958, Carpenter 1971) and consist primarily of vegetable matter throughout their range (Beckwith 1959). Diet studies in several states have indicated agricultural crops, specifically corn and wheat, were the most readily consumed plant seeds (Korshgen 1958, Carpenter 1971). Similarities observed in diets of doves were dependent on the agricultural crops available within the area. For example, in Missouri, some seasonal variability was documented suggesting doves forage based on food availability as much as by food preference (Korschgen 1958). However, in …


Inter- And Intra-Specific Interactions In Germination And Seedling Establishment Of Cheatgrass And Russian Wildrye, Erin K. Espeland Jun 2015

Inter- And Intra-Specific Interactions In Germination And Seedling Establishment Of Cheatgrass And Russian Wildrye, Erin K. Espeland

The Prairie Naturalist

Cheatgrass (Bromus tectorum) is an invasive species in the arid and semi-arid west of the USA, and is weedy in disturbed prairie landscapes. Perennial Russian wildrye (Psathyrostachys juncea) limits population growth of cheatgrass, but the mechanism is unclear. I conducted glasshouse and greenhouse experiments to test if intra- and interspecific competitive interactions of seeds and seedlings of cheatgrass and Russian wildrye were different across a geographic soil gradient with different cultivation legacies in eastern Montana, USA. Seed-seed interactions occurred in both species. Cheatgrass and Russian wildrye inhibited one another’s emergence in one edaphic condition in one experiment. Cheatgrass growth was …


West Nile Virus And Ferruginous Hawks (Buteo Regalis) In The Northern Great Plains, Shubham Datta, Jonathan A. Jenks, David E. Knudsen, Kent C. Jensen, Will M. Inselman, Christopher C. Swanson, Troy W. Grovenburg Jun 2015

West Nile Virus And Ferruginous Hawks (Buteo Regalis) In The Northern Great Plains, Shubham Datta, Jonathan A. Jenks, David E. Knudsen, Kent C. Jensen, Will M. Inselman, Christopher C. Swanson, Troy W. Grovenburg

The Prairie Naturalist

Emerging infectious diseases (EID) present significant threats to the conservation of global biodiversity (Daszak et al. 2000). Evaluating impacts (spatial, temporal and demographic) of EIDs on sensitive and declining wildlife populations is challenging because quantitative information is usually dependent on estimates rather than counts (Wobeser 2007) and mortality rates are seldom quantified with conventional monitoring (Naugle et al. 2005).

West Nile virus (WNv), a mosquito-borne Flavivirus (family Flaviviridae; Komar 2001), was discovered in northwest Uganda in 1937 (Smithburn et al. 1940). First encountered in the western hemisphere in New York in 1999 (Nash et al. 2001), WNv has become enzootic …


Using Otolith Microchemistry To Classify Yellow Perch As Stocked Or Naturally Produced, Andrew K. Carlson, Matthew J. Ward, Brian D.S Graeb Jun 2015

Using Otolith Microchemistry To Classify Yellow Perch As Stocked Or Naturally Produced, Andrew K. Carlson, Matthew J. Ward, Brian D.S Graeb

The Prairie Naturalist

Fisheries managers routinely use stocking to supplement fish populations (Schramm and Piper 1995, Fisher 1996). Stocking eyed-eggs offers substantial cost savings compared to stocking fry and fingerlings (PFBC 2011); however, traditional stocking evaluation using oxytetracycline (OTC) marking of otoliths is ineffective for eyed-eggs of some species (e.g., yellow perch, [Perca fla- vescens]). Thus, there is a need for additional approaches to be able to classify fish as stocked or naturally produced. Fish otoliths are paired calcified structures in the inner ear that permanently deposit trace elements in proportion to water column concentrations (Campana 1999, Campana et al. 2000). Coupled with …


Background Paper On Systematics, Invasive Species Advisory Committee May 2015

Background Paper On Systematics, Invasive Species Advisory Committee

National Invasive Species Council

The Invasive Species Advisory Committee (ISAC) makes recommendations to the Federal government agencies that have an invasive species portfolio. This systematics recommendation strives to motivate action in the agencies that have been identified in the Situation Report as the agencies with systematics capabilities in the Federal government.

The USDA Agricultural Research Service (ARS) and the Smithsonian Institution are repositories of a large amount of the systematics collections and human capabilities for systematics essential work on invasive species. Conducting the Survey of their systematics capabilities and needs is urgent. The Survey will describe actions in research, specimen-based collections, a biodiversity informatics …


Plant Diversity Affects Performance Of Invasive Thistles In Restored Nebraska Grasslands, Katilyn J. Price May 2015

Plant Diversity Affects Performance Of Invasive Thistles In Restored Nebraska Grasslands, Katilyn J. Price

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species threaten native grasslands, affecting nutrient cycling, biodiversity, wildlife habitat, and usable land for production. Consequently, preventing establishment of invasive species is critical before removal becomes difficult and expensive. The purpose of this study was to examine the effects of grassland plant diversity on musk thistle (Carduus nutans) and Canada thistle (Cirsium arvense) establishment and determine which environmental factors (light penetration, soil moisture, plant diversity, and soil nitrogen) account for resistance to invasions. In a field experiment at The Nature Conservancy’s Wood River site (Nebraska), the two invasive thistle species were planted into replicated …