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Effects Of Soil Erosion Barriers On Percent Cover And Sediment Size, Michael Perez

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, introducing nonnative megafauna that put selective grazing pressures on endemic species. Dense groves of island oak (Q. tomentella) are aid in sediment deposition and retention. A current restoration effort, involved installing soil erosion barriers, known as wattles, to prevent sediment from being lost upslope and recruit plant growth whose root systems could further stabilize the slope. This experiment was designed to compare percent cover of vegetation growth in areas with and without soil erosion barriers. This was done using the line intercept method (n=42) on three meter transects, measuring …

Eucalyptus In Kenya; Impacts On Environment And Society, Brandy M. Garrett Kluthe

Graduate Theses and Dissertations

Eucalyptus trees were introduced to Kenya a little over a century ago. European colonization along with the development of a railway system increased the demand for a fast growing wood source. The expansion of the tree across the fertile lands in Kenya raises concerns about the environmental impact on ecosystems where it has been introduced. These concerns include degraded soils, loss of water resources, co-introduction of ectomycorrhizal species, and allelopathy. Economic benefits to local landowners were also explored as well as the potential for large Eucalyptus woodlots to maximize the sequestration of CO₂ from the atmosphere. This was examined through …

Effects Of Invasive Shrub Honeysuckle (Lonicera Maackii) And Forest Composition On Bird Communities In Woodland Stands., Katie Rae Lynch

Electronic Theses and Dissertations

Invasive species pose a threat to aquatic and terrestrial ecosystems by decreasing biodiversity (Didham et al. 2005). Amur bush honeysuckle (Lonicera maackii) has typically reduced native plant diversity and altered animal communities by influencing animal abundance and activity (Collier and Vankat 2002). This study was intended to determine whether honeysuckle density or other characteristics of forested stands influence avian diversity, whether impacts are seasonally dependent, and whether correlations exist between attributes of forested stands and honeysuckle density. In order to test the hypotheses, thirteen forest stands within the Louisville Metropolitan Area were selected. They had similar tree composition …

Guideline For Stakeholder Engagement On Aquatic Resource Management-Related Processes, Department Of Fisheries

Fisheries Occasional Publications

No abstract provided.

The Interactive Effects Of Pesticide Exposure And Infectious Disease On Amphibian Hosts, Katherine M. Pochini

Open Access Theses

Natural systems are home to a multitude of natural and anthropogenic stressors, which draw an array of effects on ecological communities. While these effects have been investigated individually, it is important, given the routine co-occurrence of these stressors, to understand their interactive effects. Pesticide exposure and infectious disease are two common, co-occurring stressors that each have documented detrimental effects on species and, as evidence suggests, may have interactive effects. Moreover, existing research suggests that these interactive effects are highly context dependent, eliciting different results based on species, disease agent, toxin, and environment. Given the variability with which species may experience …

The Biology And Management Of Waterhemp In Indiana, Joseph M. Heneghan

Open Access Theses

Waterhemp is a dioecious weed species indigenous to the Midwestern United states yet it has only recently become problematic in agronomic crop production in Indiana. Waterhemp is a small-seeded broadleaf which has increased in prevalence in conjunction with an increase in conservation tillage practices. Waterhemp germinates and emerges from the top 3 cm of soil and is known to exhibit extended periods of continual emergence, longer than most other summer annual weed species that are typically present in agronomic production settings. As a C4 species, waterhemp then grows rapidly and is capable of producing thousands of seeds, while effectively competing …

Reflexivity: A First Demonstration, Melissa Jane Swisher

Open Access Dissertations

Currently, the emergent relation of reflexivity after training a set of baseline relations has not been demonstrated with any animal—human or nonhuman. True reflexivity can only be demonstrated if no identity (i.e., physically matching stimulus) relations are trained. In six experiments, the emergence of reflexivity and its opposite, anti-reflexivity, were explored. Pigeons received concurrent successive matching training on two or three arbitrary tasks: AB hue-form and BC form-hue (and AC hue-hue) matching. Once they had acquired these tasks, they were tested for BB (form-form) reflexivity or BB’ (form-form) anti-reflexivity matching. Most (10 of 13) pigeons that received three arbitrary tasks …

Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez

Open Access Dissertations

Habitat replacement and fragmentation associated with projected climate change pose a critical threat to global biodiversity. Edaphically limited plant species with restricted dispersal abilities will be especially handicapped to track their optimal climate spatially. Instead, the persistence of these species will depend on their capacity to adapt in situ to novel climate regimes. Here I evaluated the evolutionary potential of Lasthenia fremontii, an annual plant species restricted to ephemeral wetlands called vernal pools in California to adapt to the projected patterns of climate change. Across L. fremontii distribution there is a latitudinal gradient in precipitation which, combined with reduced …

Behavioral Differences Between Native And Exotic Invertebrate Prey Affect Susceptibility To Predation By A Native Amphibian Predator, Zachary Cava

Biology Theses

Invasive species threaten global biodiversity via mechanisms that include altering the dynamics and structure of native food webs. Whereas much research has focused on how exotic species respond to native predators, less is known about how native predators are affected by invasive prey. Here I investigate the response of a rare and threatened native predator—the Eastern Hellbender (Cryptobranchus alleganiensis) to a high-profile invasive crayfish species, Orconectes rusticus. Hellbenders have declined throughout much of their range, and although the potential for exotic predators (i.e. sport fish) to negatively impact C. alleganiensis has been addressed, effects of exotic prey …

Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.

Biology Theses

Invasive plants often dominate novel habitats where they did not co-evolve with local species. Several hypotheses suggest mechanisms that explain increased exotic plant success, including 'novel weapons' and 'degraded mutualisms'. Japanese knotweed (Fallopia japonica) and European buckthorn (Rhamnus cathartica) are widespread plant invaders in North America that can dominate ecosystems. The goal of this study is to test whether these impacts are more consistent with novel weapons or degraded mutualism hypotheses. I examine tree seedling recruitment, (germination and initial survival) growth, (biomass) and mycorrhizal invasion (AMF content) as a function of F. japonica and R. cathartica …

Forest Islands In A Sea Of Urban Habitat, Michael J. Olejniczak

Biology Theses

Urban forests are poorly defined as ecological communities. Substantive links between anthropogenic landscape features and forest ecology are lacking. ‘Urbaness’ is commonly defined by human population density or land use classifications, but their use is inconsistent throughout the literature, and rarely is linked with ecological processes. Furthermore, it is unknown whether urban forests are functioning parts of a patchy urban woodland system or isolated islands amidst an ocean of unsuitable habitat. I first used digital satellite imagery and publicly available U.S. National Park data to link urban land use with forest processes. I then linked those land use classifications with …

Stream Microbial Communities As Potential Indicators Of River And Landscape Disturbance In North-Central Arkansas, Wilson Howard Johnson

Graduate Theses and Dissertations

In the past decade, 29 shale basins have been actively developed across 20 states for extraction of natural gas (NG) via horizontal drilling/hydraulic fracturing (=fracking). This includes ~5000 wells within the Fayetteville shale of north-central Arkansas. Development often impacts both river- and landscapes, and management requires catchment-level evaluations over time, with organismal presence/absence as indicators. For this study next-generation sequencing was used to identify/characterize microbial communities within biofilm of eight Arkansas River tributaries, so as to gauge potential catchment influences. Streams spanned a gradient of landscape features and hydrological flows, with four serving as ‘potentially impacted catchment zones’ (PICZ) and …

A Review On The Invasion Ecology Of Amur Honeysuckle (Lonicera Maackii, Caprifoliaceae), A Case Study Of Ecological Impacts At Multiple Scales, Rachel E. Mcneish, Ryan W. Mcewan

Biology Faculty Publications

Invasive species are of global importance because of their impacts on ecological communities, habitat structure, native community dynamics, and ecosystem processes and function. Scientists and conservation managers are increasingly focusing on the biological impacts of invasive species and on devising management practices that emphasize the health of ecosystems based on measured biological processes. Amur honeysuckle (Lonicera maackii (Rupr.) Herder) is a highly successful invasive shrub in forests of eastern North America. The scientific literature surrounding this species has grown in the past several decades as researchers have investigated L. maackii impacts across multiple ecological scales. In this review we …

Incomplete Denitrification In Thermus Species, Chrisabelle Mefferd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Members the bacterial genus Thermus have been shown to be incomplete denitrifiers, terminating with nitrite or nitrous oxide (N2O). However, the ability to carry out denitrification and the evolution of nitrogen oxide reductase genes in Thermus remains poorly understood. This study tests the hypothesis that incomplete denitrification is common in Thermus and seeks to uncover patterns in the evolution of denitrification pathways in Thermus. Denitrification capacity was determined in a collection of 25 strains representing ten species of Thermus and phylogenetic analysis was performed to determine whether denitrification genes evolved horizontally in Thermus. No strains in this study reduced nitrate …

Ecological And Phenotypic Factors Influencing The Movement Dynamics Of The Blackspotted Topminnow, Fundulus Olivaceus, Scott Richard Clark

Dissertations

Movement of individuals throughout a landscape is a complex behavior that has important consequences on numerous ecological and evolutionary processes. Perhaps most notably is the relationship between movement and reproduction, as this has implicit ramifications on individual fitness and consequently, population level processes. Although this relationship has been theoretically and empirically demonstrated across a number of animal taxa, its role in fishes remains understudied and largely unknown. Using a series of outdoor mesocosms, in combination with a field study, I employed passive integrated transponder (PIT) tags to experimentally assess the sex-specific movement dynamics of a small-bodied, sexually-dimorphic stream fish, the …

Blackbirds, Richard A. Dolbeer, George M. Linz

Wildlife Damage Management Technical Series

The term blackbird loosely refers to a diverse group of about 10 species of North American birds that belong to the avian family Icteridae. The most common species include: Red-winged blackbird (Agelaius phoeniceus) Common grackle (Quiscalus quiscula) Great-tailed grackle (Quiscalus mexicanus) Brown-headed cowbird (Molothrus ater) Yellow-headed blackbird (Xanthocephalus xanthocephalus) Brewer’s blackbird (Euphagus cyanocephalus) Rusty blackbird (Euphagus carolinus) In addition to blackbirds, this family includes orioles, meadowlarks, and bobolinks.

Human-Wildlife Conflicts 1 Damage Identification 3 Management Methods 4 Economics 7 Species Overview 8 Legal Status 11 Glossary …

Double-Crested Cormorants, Brian S. Dorr, Kristi L. Sullivan, Paul D. Curtis, Richard Chipman, Russell D. Mccullough

Wildlife Damage Management Technical Series

The history of conflict between double-crested cormorants (Figure 1) and human interest in fisheries is long and convoluted. Following a low point in the 1970s, populations of cormorants expanded in North America, as did concerns about impacts on fisheries. By the late 1990s, natural resource agencies in 27 states reported losses of free-ranging fish stocks to cormorants. Agencies in 10 states, ranging from the Southwest to the Northeast, considered cormorant predation to be of moderate to major concern to fishery management.

Overall, double-crested cormorants are not major consumers of commercial and sportfish species. However, exceptions have been recorded at specific …

Bird Dispersal Techniques, Thomas W. Seamans, Allen L. Gosser

Wildlife Damage Management Technical Series

Conflicts between humans and birds likely have existed since agricultural practices began. Paintings from ancient Greek, Egyptian, and Roman civilizations depict birds attacking crops. In Great Britain, recording of efforts at reducing bird damage began in the 1400s, with books on bird control written in the 1600s. Even so, the problem persists. Avian damage to crops remains an issue today, but we also are concerned with damage to homes, businesses, and aircraft, and the possibility of disease transmission from birds to humans or livestock. Successful dispersal techniques should capitalize on bird sensory capabilities. If birds cannot perceive the dispersal technique, …

Geese, Ducks And Coots, John L. Cummings

Wildlife Damage Management Technical Series

Canada geese, snow geese, ducks, and American coots all have been implicated in agricultural crop and turf damage. Canada geese and snow geese that graze on winter wheat and rye crops can reduce subsequent grain and vegetative yields. Canada geese also cause serious damage to sprouting soybeans in spring and to standing cornfields in the autumn. The most common damage to agricultural resources associated with geese results from consumption of crops. Other impacts involve unacceptable accumulations of feces in pastures, trampling of emerging crops, and increased erosion and runoff from fields where the cover crop has been grazed. Canada geese …

Effect Of Migration, Carrying Capacity, And Fecundity On The Formation Of Clinal Patterns During Range Expansions., Neha J. Angal

Electronic Theses and Dissertations

Range expansions, empirically and in simulations, lead to clinal patterns of genetic diversity. Clines are often used as spatial markers of past migrations. This study investigated the effects of migration, growth, and carrying capacities on clinal patterns during range expansions, using forward-time simulations in Nemo. Initial results show, in the absence of prior population structure, range expansions result in a loss of diversity strongly affected by migration, growth, and carrying capacity. This loss of diversity did not persist to the final generation, corresponding to 10,000 years, indicating clinal patterns are less durable than previously assumed—challenging the utility of clinal patterns …

Effect Of Dung Beetles On Dung Decomposition And Nutrient Cycling In A Nebraska Rangeland, Kenneth Shay Evans

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

Management practice can have impacts on the abundance and frequency of dung beetle populations and nutrient cycling in grazing systems. Also, agriculture and livestock production land use is a considerable source of anthropogenic greenhouse gas (GHG) emissions, which are known to be one of the causes of global climate change. In this study, we evaluated the effect of dung beetle presence on the fluxes of greenhouse gasses (GHG’s) from dung pats in the semi-arid Sandhills region of Nebraska, by using closed chambers to measure the fluxes of carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N …

Gang Behavior At Carcasses In Wintering Striated Caracaras (Phalcoboenus Australis) In The Falkland Islands, Anna Rose Autilio

Boise State University Theses and Dissertations

Avian scavengers perform vital ecosystem services by removing waste and by slowing disease. Yet few details are known about the purpose or purposes of social interactions near carcasses and their role in the physical depletion of carcasses (Gangoso et al. 2013). The globally Near-Threatened Striated Caracara is a social scavenging falconid that relies on seabird colonies for food during the breeding season in the Falkland Islands, a principal stronghold in its range. The birds have been persecuted as livestock pests since the late 1800s. Although the population is now protected and remains stable, it does not appear to be growing. …

Gyrfalcon Diet During The Brood Rearing Period On The Seward Peninsula, Alaska, In The Context Of A Changing World, Bryce W. Robinson

Boise State University Theses and Dissertations

As climate change impacts increase so does our need to understand their effects on ecosystem dynamics. I studied Gyrfalcon (Falco rusticolus) diet during the brood rearing period to improve our knowledge on dietary habits during nesting, and provide necessary information for understanding climate change impacts to Arctic ecosystems. I studied diet over two breeding seasons on the Seward Peninsula, Alaska, using two methods: motion-activated cameras and the collection of prey remains. I observed three important dietary shifts: the proportion of ptarmigan in the diet declined significantly throughout the season, the proportion of large prey items declined significantly throughout …

An Investigation Of Herbivory And Seed Predation On Slickspot Peppergrass, Michelle I. Jeffries

Boise State University Theses and Dissertations

This study was completed during the summers of 2014 and 2015 to continue research on the relationship between harvester ants (Pogonomyrmex salinus) and slickspot peppergrass (Lepidium papilliferum). Slickspot peppergrass is a rare mustard endemic to south western Idaho. Over the past century, the species has declined in abundance, largely as a result of habitat degradation and fragmentation. In addition to these reasons for decline, seed foraging by harvester ants and plant destruction by harvester ants and small mammal herbivores have been recently indicated as potential factors. This study confirmed that harvester ants remove large numbers of …

Genetic Analysis Of Eurasian Populations Of Taeniatherum Caput-Medusae Subspecies Asperum: Biogeography Of An Invasive, Self-Pollinating, Annual Grass In Its Native Range, Peter Guerdan

Boise State University Theses and Dissertations

Understanding species’ distributions provides a comprehensive biogeographical framework with which to evaluate theoretical and applied ecological and evolutionary questions. To date, few studies have used amplified fragment length polymorphisms (AFLPs) to assess the biogeographical patterns of a broadly distributed grass species, and none that I have found used AFLPs to specifically study biogeographical patterns of an invasive annual grass in its native range. The overall objective of my study was to assess the biogeographic pattern of the invasive, self-pollinating, annual grass Taeniatherum caput-medusae subspecies asperum (medusahead) in its native range in Eurasia using AFLPs. Seventy populations of medusahead from 13 …

Earlier Nesting By A Predatory Bird Is Associated With Human Adaptations To Climate Change, Shawn Heath Smith

Boise State University Theses and Dissertations

Advancing growing seasons and prey abundance drive earlier breeding in dietary specialists because, ultimately, consumers benefit by timing their reproduction to coincide with peak prey abundance. The selective pressure to breed earlier may be lower for species that forage on diverse prey items that vary in abundance both spatially and temporally. The selective pressure may be reduced further if predators have access to a mosaic of habitats, each of which having different shifts in growing seasons. We studied whether earlier breeding of a predatory generalist, the American kestrel (Falco sparverius) nesting in a mosaic of habitat types was …

Water Source Partitioning For Shrubland Transpiration In A Mixed Phreatophytic Plant Community, Amanda Jean Wagner

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater in the basins of east central Nevada (Great Basin Desert, NV) has been permitted for export to southern Nevada. These basins are also vulnerable to changes in climate that could lead to declining recharge. Any decline in groundwater levels no matter the driving force could significantly impact phreatophytes (deep rooted shrubs), which utilize water from both the vadose zone and the capillary fringe to meet plant water needs, to support growth, and for overall health. A reduction in groundwater due to these forces could have a significant impact on the decoupling of phreatophytes from what is normally a reliable …

Polyandry In The Absence Of Fitness Benefits In A Species With Female-Biased Sexual Size Dimorphism, Marie Claire Chelini, Eileen A. Hebets

Eileen Hebets Publications

Most studies exploring the evolution of female mating systems focus on species in which females are either monandric (mate with a single male) or highly polyandric (mate with multiple males), but less is understood about variation in mating decisions within a species. How and why do females of a single species decide whether or not to copulate with additional mates? In this study we attempt to answer this question in the highly dimorphic crab spider, Mecaphesa celer, whose females may be either monandric or polyandric. We tested three hypotheses: (1) a female’s decision to remate is based on sequential mate …

Cryptosporidium Parvum Among Coprolites From La Cueva De Los Muertos Chiquitos (600–800 Ce), Rio Zape Valley, Durango, Mexico, Johnica J. Morrow, Karl Reinhard

Karl Reinhard Publications

In the present study, 90 coprolites from La Cueva de los Muertos Chiquitos (CMC) were subjected to enzyme-linked immunosorbent assay (ELISA) tests for 3 diarrhea-inducing protozoan parasites, Entamoeba histolytica, Giardia duodenalis, and Cryptosporidium parvum, to determine whether these parasites were present among the people who utilized this cave 1,200–1,400 yr ago. These people, the Loma San Gabriel, developed as a culture out of the Archaic Los Caracoles population and lived throughout much of present-day Durango and Zacatecas in Mexico. The Loma San Gabriel persisted through a mixed subsistence strategy of hunting-gathering and agricultural production. The results of …

Development Of Genomic Resources For The Evaluation Of Red Snapper, An Emerging Species Candidate For Marine Aquaculture And Stock Enhancement, Adrienne Elise Norrell

Master's Theses

The northern red snapper (Lutjanus campechanus) is a highly targeted reef fish candidate for marine aquaculture and stock enhancement in the southern United States. This work aimed to develop genomic resources for the genetic management of aquaculture programs and to investigate population structure using high-throughput sequencing technologies. Eighty-four new microsatellite markers were developed through screening of Illumina paired-end sequencing reads. Microsatellite loci and Single Nucleotide Polymorphisms (SNPs) generated through Restriction Site Associated DNA (RAD) sequencing were assayed in 5 outbred full-sib families to construct a high-density linkage map of the red snapper genome. The map consists of 7,964 …