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Birds Of The Central Platte River Valley And Adjacent Counties, Mary Bomberger Brown, Paul A. Johnsgard

Zea E-Books Collection

The central Platte River Valley region of Nebraska is described ecologically, and defined as encompassing 11 counties and nearly 10,000 square miles, and extending about 120 miles from the western edge of Lincoln County to the eastern edge of Merrick County. At its center is the Platte River, the historic spring staging area for Sandhill and Whooping cranes, five species of geese, and millions of waterfowl and water-dependent birds, in addition to providing the breeding habitats for more than 100 other bird species. Collectively, at least 373 bird species have been reported from the Central Platte Valley, making it the …

Using Stable Isotope Analysis Of Zooplankton To Document Trophic And Biogeochemical Changes In The San Francisco Estuary, Steven C. Westbrook, Julien Moderan

STAR Program Research Presentations

Zooplankton represent a vital link between phytoplankton and fish, like the endangered Delta Smelt. Human interferences (nitrates from waste water, flow alteration, invasive species introduction…) have altered the structure of the San Francisco Estuary (SFE) ecosystem. We use stable isotope analysis to improve our knowledge of the planktonic food web in the SFE and gain insights into its evolution over the past decades. We use the ratios of certain isotopes (Nitrogen, Carbon, Sulfur, etc.) in different species of zooplankton to tell us what it is feeding on as well as the trophic level it feeds in. My research focused on …

Imaginenative 2012: Ecocinema And The Indigenous Film Festival, Salma Monani, Miranda Brady

Environmental Studies Faculty Publications

Much scholarship points to how ecological concerns are never far from Indigenous struggles for political sovereignty and public participation. In this paper we turn to the Indigenous film festival as a relatively understudied yet rich site to explore such ecological concerns. Specifically, we highlight the ImagineNATIVE 2012 film festival based in Toronto, Canada.

Consequences Of Climate Change For The Soil Climate In Central Europe And The Central Plains Of The United States, Miroslav Trnka, Kurt Christian Kersebaum, Josef Eitzinger, Michael Hayes, Petr Hlavinka, Mark Svoboda, Martin Dubrovský, Daniela Semerádová, Brian D. Wardlow, Eduard Pokorný, Martin Možný, Donald A. Wilhite, Zdeněk Žalud

National Drought Mitigation Center: Faculty Publications

This study aims to evaluate soil climate quantitatively under present and projected climatic conditions across Central Europe (12.1°–18.9° E and 46.8°–51.1° N) and the U.S. Central Plains (90°–104° W and 37°–49° N), with a special focus on soil temperature, hydric regime, drought risk and potential productivity (assessed as a period suitable for crop growth). The analysis was completed for the baselines (1961–1990 for Europe and 1985–2005 for the U.S.) and time horizons of 2025, 2050 and 2100 based on the outputs of three global circulation models using two levels of climate sensitivity. The results indicate that the soil climate (soil …

Spring Clipping, Fire, And Simulated Increased Atmospheric Nitrogen Deposition Effects On Tallgrass Prairie Vegetation, Alexander J. Smart, Tabitha K. Scott, Sharon A. Clay, David E. Clay, Michelle K. Ohrtman, Eric M. Mousel

Agronomy, Horticulture and Plant Science Faculty Publications

Defoliation aimed at introduced cool-season grasses, which uses similar resources of native grasses, could substantially reduce their competitiveness and improve the quality of the northern tallgrass prairie. The objective was to evaluate the use of early season clipping and fire in conjunction with simulated increased levels of atmospheric nitrogen deposition on foliar canopy cover of tallgrass prairie vegetation. This study was conducted from 2009 to 2012 at two locations in eastern South Dakota. Small plots arranged in a split-plot treatment design were randomized in four complete blocks on a warm-season grass interseeded and a native prairie site in east-central South …

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

Promoting Amphibian Conservation Through The College Classroom: Detection Of Batrachochytrium Dendrobatidis Among Local Amphibians, Julie Wunder, Noel Lampazzi, Kelsey Acre, Nicholas Bent, Sadie Canter, Alexandra Chapman, Margaret Davies, David Kashan, Jonathan Keiley, Rachel Macintyre, Tamara Milton, Kara Weichler, Matthew Wilson, Mizuki Takahashi

Faculty Journal Articles

Many global amphibian declines have been linked to the fungal pathogen Batrachochytrium dendrobatidis (Bd). The knowledge on Bd distribution provides a fundamental basis for amphibian conservation planning. Yet, such Bd distribution information is currently insufficient, in particular at a regional scale. The college classroom provides an excellent opportunity to expand the knowledge of Bd distribution. Here we provide an example of such research projects to detect Bd prevalence among local amphibians in a college course setting and present the results of work conducted in central Pennsylvania, USA. We collected toe clips and conducted PCR assays of six species, …

Ecology And Invasive Properties Of Musk Thistle (Carduus Nutans) In The Central Prairies Of Nebraska, Chengchou Han

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

Musk thistle (Carduus nutans) is an herbaceous monocarpic herb introduced to the U. S. from Eurasia. The invasion of musk thistle can reduce forage area, soil stability, and reduce recreation and open areas for humans and wildlife.

Resistance of warm season and cool season perennial grass communities to musk thistle invasion is important for land managers to consider, especially where disturbance has made an area particularly susceptible. Our results show that disturbances, such as overgrazing can open up niches in canopies of warm season grass communities and facilitate invasion but not in cool season grass communities. The mechanism …

Soil Nematodes And Their Prokaryotic Prey Along An Elevation Gradient In The Mojave Desert (Death Valley National Park, California, Usa), Amy M. Treonis, Kelsey Sutton, Brendan Kavanaugh, Archana Narla, Timothy Mcllarky, Jasmine Felder, Cecilia O'Leary, Megan Riley, Alyxandr Pikus, Sarah Thomas

Biology Faculty Publications

We characterized soil communities in the Mojave Desert across an elevation gradient. Our goal was to test the hypothesis that as soil quality improved with increasing elevation (due to increased productivity), the diversity of soil prokaryotes and nematodes would also increase. Soil organic matter and soil moisture content increased with elevation as predicted. Soil salinity did not correlate to elevation, but was highest at a mid-gradient, alluvial site. Soil nematode density, community trophic structure, and diversity did not show patterns related to elevation. Similar results were obtained for diversity of bacteria and archaea. Relationships between soil properties, nematode communities, and …

Behavioral And Physiological Female Responses To Male Sex Ratio Bias In A Pond-Breeding Amphibian, Kristine L. Grayson, Stephen P. De Lisle, Jerrah E. Jackson, Samuel J. Black, Erica J. Crespi

Biology Faculty Publications

Introduction: The phenomenon of sexual conflict has been well documented, and in populations with biased operational sex ratios the consequences for the rarer sex can be severe. Females are typically a limited resource and males often evolve aggressive mating behaviors, which can improve individual fitness for the male while negatively impacting female condition and fitness. In response, females can adjust their behavior to minimize exposure to aggressive mating tactics or minimize the costs of mating harassment. While male-male competition is common in amphibian mating systems, little is known about the consequences or responses of females. The red-spotted newt (Notophthalmus …

Functional Response Of Protected Larval Stage Delta Smelt (Hypomesus Transpacificus), Jorge Ruiz, Lindsay Sullivan, Wim Kimmerer, Joan Lindberg

STAR Program Research Presentations

Delta smelt (Hypomesus transpacificus) is a protected slender-bodied fish endemic to the San Francisco Estuary. Smelt prey upon various zooplankton including the copepods such as Pseudodiaptomus forbesi. This experiment studied the prey maximum feeding rate of 2 larval stages (21 DHP, 35 DPH) of Delta smelt on various concentrations of P. forbesi. The copepod prey was offered at 7 different concentrations (2No./L–120No./L). After feeding was terminated the free prey and ingested prey were counted and analyzed to find the feeding rate of Delta smelt. Maximum feeding rate was found to be at much higher prey densities …

Developing Monitoring Methods For Leptasterias Spp. As Sentinel Species In Detecting Local Environmental Changes, Zachary Sturbaum, Kathryn Nuessly, Riley J. Smith, C. Sarah Cohen

STAR Program Research Presentations

Leptasterias spp., a six-rayed sea star, is found in rocky intertidal habitats ranging from Alaska to central California. Leptasterias spp. can be monitored on a broad scale throughout their range by a variety of means using timed counts and random plot censusing in order to detect both large-scale and local-level changes in the environment due to climate change, land-based human activity, or other environmental events. Leptasterias brood their young externally until the embryos grow into fully developed juveniles. These juveniles disperse by crawling away, limiting their dispersal potential. This localized dispersal provides an opportunity to use Leptasterias spp …

Testing The Salinity Tolerance Levels Of Similar Invasive Species Found In The San Francisco Bay, Julia M. Smith, C. Sarah Cohen, Elizabeth Sheets

STAR Program Research Presentations

Testing the salinity tolerance levels of similar invasive species found in the San Francisco Bay

Julia Smith^1,2, Elizabeth Sheets², and C. Sarah Cohen²

¹Department of Teacher Education, California State University, Sacramento ²Department of Biology and Romberg Tiburon Center, San Francisco State University

Three non-indigenous colonial ascidian species, Botrylloides violaceus, Botrylloides diegensis, and Botryllus schlosseri, have become well established in San Francisco Bay. Two species, B. violaceous and B. schlosseri, are globally distributed, and understanding the salinity ranges and tolerances of these successful invaders in their introduced habitats is important for …

Trophy Hunting And Trophy Size In Ugalla Game Reserve, Western Tanzania, P Wilfred

Tanzania Journal of Science

The present paper explores trends and variations in trophy size among wildlife species hunted in the Ugalla Game Reserve (UGR) of western Tanzania, in relation to hunting success (animals shot species-1 quota-1). Data on trophy hunting from 2006 – 2010 were obtained from the UGR office in Tabora Region. Forty-seven species were targeted by trophy hunters. Hunting success differed significantly across the species (Generalised Linear Model [GLM] with a binomial error structure: deviance chi-square [X2] = 9.64, d.f. = 44, p<0.001). Twenty-eight species had trophy size measurements, but only 6 species had measurements taken consistently throughout the data period. Although most of the shot animals were above their minimum trophy size limits (official trophy limits below which animals could not be removed) there was significant variation among species (GLM with normal errors: F5,201 = 509.12, p<0.001). Time (years) had no significant effect on trophy size, but the trend over time in trophy size differed significantly among species (F5,194 = 5.42, p<0.001). Of the trophy species, greater kudu (Tragelaphus strepsiceros) had the largest mean trophy size, whereas warthog (Phacochoerus africanus) had  the lowest trophy size and showed a considerable decline. The majority of the animals had trophy sizes hovering just above their minimum limits. This should be monitored rigorously to avoid removing large numbers of actively breeding animals.

The Likelihood Of Extinction Of Iconic And Dominant Herbivores And Detritivores Of Coral Reefs: The Parrotfishes And Surgeonfishes, Mia T. Comeros-Raynal, John H. Choat, Beth A. Polidoro, Kendall D. Clements, Rene Abesamis, Matthew T. Craig, Muhammad E. Lazuardi, Jennifer Mcilwain, Andreas Muljadi, Robert F. Myers, Cleto L. Nanola Jr., Shinta Pardede, Luiz A. Rocha, Barry Russell, Jonnell C. Sanciangco, Brian Stockwell, Heather Harwell, Kent E. Carpenter

Biological Sciences Faculty Publications

Parrotfishes and surgeonfishes perform important functional roles in the dynamics of coral reef systems. This is a consequence of their varied feeding behaviors ranging from targeted consumption of living plant material (primarily surgeonfishes) to feeding on detrital aggregates that are either scraped from the reef surface or excavated from the deeper reef substratum (primarily parrotfishes). Increased fishing pressure and widespread habitat destruction have led to population declines for several species of these two groups. Species-specific data on global distribution, population status, life history characteristics, and major threats were compiled for each of the 179 known species of parrotfishes and surgeonfishes …

Increase In Ponderosa Pine Density In The Nebraska Sandhills: Impacts On Grassland Plant Diversity And Productivity, Alexa Armstrong

Department of Environmental Studies: Undergraduate Student Theses

Increase in woody species encroachment into semi-arid grasslands and savannas has been of great concern at a global level. Temperature and precipitation are key factors determining vegetation cover; however other factors, such as fire regime and grazing may be at play in semi-arid ecosystems. Historically, in Nebraska’s semi-arid grasslands, woody species have been controlled by periodic fires. Changes in social values and land use, fire suppression, overgrazing, increased N deposition, and climate change, have attributed to the observed shift from grasslands to shrublands or woodlands. The primary objectives of this study were to determine the impacts of Ponderosa pine ( …

Exploring The Seed Bank Dynamics Of Red Brome: Longevity, Density, And Relationship To Fire, Benjamin S. Jurand

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research explores several untested aspects of the seed bank characteristics of red brome (Bromus rubens), an invasive annual grass in southwestern United States arid lands. Red brome is a formidable competitor to native plant species, both annual and perennial alike, and produces many seeds that germinate easily. The stalks of red brome contribute continuous-cover fuel loads that facilitate wildfires destructive to mature native Mojave Desert plant communities. This makes it a priority species for land managers, particularly when dealing with recovery after fire.

This project addressed questions related to the longevity of red brome seeds in soil seed banks …

Investigating Three Decades Of Vegetation Change In A Mojave Desert Mountain Range, Chris Lee Roberts

UNLV Theses, Dissertations, Professional Papers, and Capstones

This project is a vegetation change study spanning 29 years in the Newberry Mountains of Southern Nevada. Long term monitoring data are crucial for understanding the effects of climate change on vegetation dynamics. Successful management intervention in vegetation change will require identification of early indicator plant species and their responses to climatic cues. This project is one of the oldest comparisons of resurveyed Mojave vegetation community plots with repeatable methodology and the longest survey interval reported for the southeastern Mojave Desert. 103 plots were relocated and resurveyed based on data methods in Jim Holland's thesis titled "A Vegetative Analysis of …

Effects Of Vegetation, Corridor Width And Regional Land Use On Early Successional Birds On Powerline Corridors, Robert A. Askins, Corrine M. Folsom-O'Keefe, Margaret C. Hardy

Biology Faculty Publications

Powerline rights-of-way (ROWs) often provide habitat for early successional bird species that have suffered long-term population declines in eastern North America. To determine how the abundance of shrubland birds varies with habitat within ROW corridors and with land use patterns surrounding corridors, we ran Poisson regression models on data from 93 plots on ROWs and compared regression coefficients. We also determined nest success rates on a 1-km stretch of ROW. Seven species of shrubland birds were common in powerline corridors. However, the nest success rates for prairie warbler (Dendroica discolor) and field sparrow (Spizella pusilla) were

A Postulate For Tiger Recovery: The Case Of The Caspian Tiger, Carlos A. Driscoll, I Chestin, H Jungius, Y Darman, E Dinerstein, J Seidensticker, J Sanderson, S Christie, S J. Luo, M Shrestha, Y Zhuravlev, O Uphyrkina, Y V. Jhala, S P. Yadav, D G. Pikunov, N Yamaguchi, D E. Wildt, J D. Smith, Marker, Philip J. Nyhus, R Tilson, D W. Macdonald, S J. O'Brien

Faculty Scholarship

Recent genetic analysis has shown that the extinct Caspian Tiger (P. t. virgata) and the living Amur Tigers (P. t. altaica) of the Russian Far East are actually taxonomically synonymous and that Caspian and Amur groups historically formed a single population, only becoming separated within the last 200 years by human agency. A major conservation implication of this finding is that tigers of Amur stock might be reintroduced, not only back into the Koreas and China as is now proposed, but also through vast areas of Central Asia where the Caspian tiger once lived. However, under the current tiger conservation …

The Fine-Scale Habitat Use Of Risso’S Dolphins Off Bardsey Island, Cardigan Bay (Uk), Marijke N. De Boer, Sonja Eisfeld, Mark P. Simmonds

Ecology Collection

The main objectives of this study were (1) to estimate the population size of Risso’s dolphins off Bardsey Island using mark-recapture techniques (De Boer et al., 2013); and (2) to study habitat-use in relation to fine-scale oceanographic features. This work provides preliminary information on the habitat-use of Risso’s dolphins and will benefit future studies, along with the development of effective conservation measures for this species throughout the region.

Cetaceans And Marine Debris: The Great Unknown, Mark Peter Simmonds

Ecology Collection

Plastics and other marine debris have been found in the gastrointestinal tracts of cetaceans, including instances where large quantities of material have been found that are likely to cause impairment to digestive processes and other examples, where other morbidity and even death have resulted. In some instances, debris may have been ingested as a result of the stranding process and, in others, it may have been ingested when feeding. Those species that are suction or “ram” feeders may be most at risk. There is also evidence of entanglement of cetaceans in marine debris. However, it is usually difficult to distinguish …

Winter 2012, Nsu Oceanographic Center

Currents

No abstract provided.

Grts And Graphs: Monitoring Natural Resources In Urban Landscapes, Todd R. Lookingbill, John Paul Schmit, Shawn L. Carter

Geography and the Environment Faculty Publications

Environmental monitoring programs are an important tool for providing land managers with a scientific basis for management decisions. However, many ecological processes operate on spatial scales that transcend management boundaries (Schonewald-Cox 1988). For example, adjacent lands may influence protected-area resources via edge effects, source-sink dynamics, or invasion processes (Jones et al. 2009). Hydrologic alterations outside management units also may have profound effects on the integrity of resources being managed (Pringle 2000). The impacts of climate change are presenting challenges to resource management at local-to-global scales (Karl et al. 2009). This potential disparity between ecological and political boundaries presents an interesting …

Fine Roots Of Aspen Clones In High Salt And Petroleum Hydrocarbon Pollution, Kim Yrjälä, Ivika Ostonen, Shinjini Mukherjee, Timo Sipila, Lu-Min Vaario, Pertti Pulkkinen

Aspen Bibliography

The quality of polluted soil can much be improved and the environmental risks reduced by use of phytoremediation. Harmful hydrocarbon compounds can be degraded through the activity of plant and its associated microbes. We previously showed that PAHs increase aromatic ring-cleavage gene diversity in rhizosphere of birch (Sipilä et al. 2008, Yrjälä et al. 2010a) and the rhizosphere of aspen harbors Burkholderia bacteria able to degrade aromatics (Yrjälä et al. 2010b). The results are promising for successful remediation of polluted soils with woody plants. The aim of our studies is to elucidate the response of the plant and the associated …

A Comparison Of The Effectiveness Of Scent Lures On Attracting Mesopredators, Tom Batter

Department of Environmental Studies: Undergraduate Student Theses

A mesopredator is a medium-sized middle trophic level predator such as a raccoon (Procyon lotor), red fox (Vulpes vulpes), striped skunk (Mephitis mephitis), or coyote (Canis latrans; Crooks and Soule 1999). Mesopredators have long been trapped for recreational, economic, or academic reasons. Throughout human history trapping has been used to capture animals for food and skins, as well as to prevent personal harm and property damage from predators. In order to increase the probability of success, scent lures are often used as an attractant (Geary 1984, Mills et al. 2010, Schlexer 2008).

Herpetofaunal Diversity At Yankee Hill State Lake And Wildlife Management Area, Lancaster County, Nebraska, Shelby Klima

Department of Environmental Studies: Undergraduate Student Theses

A survey for amphibians and reptiles was conducted in March through October 2011 at Yankee Hill Wildlife Management Area in Lancaster County, Nebraska. The survey was conducted using several different techniques including: visual and auditory encounters, artificial and natural cover objects, aquatic trappings and road surveys. A total of 145 individuals representing 12 species were identified including seven reptiles and five amphibians. A total of 48% of the species that may potentially occur on the site were encountered, all of which are common, widely distributed generalist species. Neither Graham’s Crayfish Snake nor the Massasauga, both target species for this survey, …

Avian Species Abundance In Response To Recreational Trail Use, Carrie A. Wencel

Department of Environmental Studies: Undergraduate Student Theses

Studies have indicated that non-consumptive outdoor recreation may affect wildlife. Thus, as the nation increases interest in outdoor recreation, data suggests the effect on wildlife will also increase. Previous studies indicate that as disturbance to wildlife increases, both avian species richness will decrease. Knowing how to anticipate effects on native species when planning and managing recreational areas is important in order to both provide for human desires and ensure the least impact to local species diversity.

The goal of this project was to observe and compare avian species richness and diversity between selected trail sites within Shevlin Park, Bend, Oregon …

Prey Selection By The Northern Watersnake, Nerodia Sipedon, Kyle O' Connell

Department of Environmental Studies: Undergraduate Student Theses

Prey selection and composition of the northern waternake, Nerodia sipedon was investigated between 8/2010 and 3/2011 by palpation of stomach contents in the field and conducting laboratory trials. 41 snakes were captured, five yielded prey contents. Fish parts, freshwater mussels, and an insect exoskeleton were found. No amphibians were found despite availability at study sites. Snakes in the laboratory underwent 22 trials, feeding on 11 occasions. Snakes fed on an equal number of both fish species, revealing no selection. Further research is needed to determine the rate of digestion of N. sipedon.

Environmental Impact Of The Three Kids Mine Tailings, Henderson, Nv, Ji Hye Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focused on the distribution of the Three Kids Mine tailings in surface soils in and around the mine in Henderson, Nevada. It is situated next to the communities of Calico Ridge and Lake Las Vegas Resort, and, just the west of the Lake Mead Recreation area. Even though the mine has been inactive for almost 50 years (1917-1961), tailing piles and other sources of contamination on the mine are currently exposed to the atmosphere. In this study, surface soil samples were collected along eight transects emanating from the center of Three Kids Mine tailing piles up to five …