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Plant-Microbial Interactions Are Strong Determinants Of Plant Population And Community Dynamics, Yan-Yi Anny Chung 9485698 2017 University of New Mexico

Plant-Microbial Interactions Are Strong Determinants Of Plant Population And Community Dynamics, Yan-Yi Anny Chung 9485698

Biology ETDs

Plant-microbial interactions are ubiquitous and yet the consequences of these interactions on plant population and community dynamics are relatively unknown. Here, we used two different classes of plant-microbial interactions to examine their effects on key plant population and community characteristics such as commonness and rarity, competition and coexistence, as well as community stability.

Vertically-transmitted endophytes had stage-dependent effects on the population growth of two grass species Poa sylvestris and Poa alsodes, and generally increased host population growth rates. However, it was the intrinsic demographic advantage of P. sylvestris that allowed its population to grow at a much faster rate …


Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett 2017 East Tennessee State University

Range-Wide Prevalence And Impacts Of Pseudocercosporella Inconspicua On Lilium Grayi And An Assessment Of L. Superbum And L. Michauxii As Reservoirs, Cindy L. Barrett

Electronic Theses and Dissertations

Lilium grayi (Gray’s Lily), a southern Appalachian endemic species, is threatened by a Lilium-specific fungal pathogen, Pseudocercosporella inconspicua. The disease is characterized by tan lesions that can cause early senescence, while also lowering seed production and viability. This project tested for P. inconspicua conidia and accessed health at nine locations. The disease was present and ubiquitous across the range of L. grayi. Through identification of P. inconspicua conidia in the field, L. superbum (Turk’s Cap Lily) was identified as an additional host, while L. michauxii (Michaux’s Lily) was disease-free. However, infection was inducible in both species. With …


Assessment Of The Calling Detection Probability Throughout The Day Of Two Invasive Populations Of Bullfrog (Lithobates Catesbeianus) In Uruguay, Gabriel Laufer, Noelia Gobel, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. de Sá 2017 University of Richmond

Assessment Of The Calling Detection Probability Throughout The Day Of Two Invasive Populations Of Bullfrog (Lithobates Catesbeianus) In Uruguay, Gabriel Laufer, Noelia Gobel, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá

Biology Faculty Publications

Bullfrog invasion is a major conservation concern in South America, so there is an urgent need to detect and monitor its many invasion foci. Amphibian sampling methods commonly use calling display, specifically the nuptial calls of males. With the aim of obtaining the better day period to sample and monitor Lithobates catesbeianus presence, we recorded its calls at three ponds in two invaded localities in Uruguay (Aceguá, Cerro Largo, and San Carlos, Maldonado) during the reproductive season. Then, we studied the records, obtaining a subsample of calling intensity at the first 5 minutes for each hour. We detected that vocalization …


Ecological Importance Of Invader Source Population And Disturbance In Aquatic Invasions, Nicole Elizabeth Graham 2017 University of Arkansas, Fayetteville

Ecological Importance Of Invader Source Population And Disturbance In Aquatic Invasions, Nicole Elizabeth Graham

Graduate Theses and Dissertations

Invasive species are a global problem and their effects on recipient ecosystems may be mediated by disturbance and intraspecific variation. Crayfish can substantially influence stream structure and function, and invasive crayfish often have differential impacts than native crayfish in aquatic ecosystems. Since species traits often vary across a distribution, it is possible that invasive crayfish from different source populations may have distinct impacts on recipient ecosystem structure and function. In the Ozark Highlands of Arkansas and Missouri, USA, invasive O. neglectus (the Ringed Crayfish) may be leading to the displacement of native O. eupunctus (the Coldwater Crayfish). The objective of …


The Behavior And Ecology Of Cursorial Predators And Dangerous Prey: Integrating Behavioral Mechanisms With Population-Level Patterns In Large Mammal Systems, Aimee Tallian 2017 Utah State University

The Behavior And Ecology Of Cursorial Predators And Dangerous Prey: Integrating Behavioral Mechanisms With Population-Level Patterns In Large Mammal Systems, Aimee Tallian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Driving into Yellowstone National Park for the first time is a moving experience. Gazing over the sweeping landscapes, seeing a geyser erupt 80 feet into the air, and having your first ‘wildlife encounter’, whether that be a 2 ton bull bison aggressively wallowing on his dirt mound, snorting and kicking up dust, or watching a pack of 6 wolves move through a valley off in the distance, pausing to howl in search of their companions. Yellowstone staff wishes to manage our park in a way that preserves these remarkable experiences. In order to effectively manage this dynamic ecosystem, it is …


Gregariousness Does Not Vary With Geography, Developmental Stage, Or Group Relatedness In Feeding Redheaded Pine Sawfly Larvae, John W. Terbot II, Ryan L. Gaynor, Catherine R. Linnen 2017 University of Kentucky

Gregariousness Does Not Vary With Geography, Developmental Stage, Or Group Relatedness In Feeding Redheaded Pine Sawfly Larvae, John W. Terbot Ii, Ryan L. Gaynor, Catherine R. Linnen

Biology Faculty Publications

Aggregations are widespread across the animal kingdom, yet the underlying proximate and ultimate causes are still largely unknown. An ideal system to investigate this simple, social behavior is the pine sawfly genus Neodiprion, which is experimentally tractable and exhibits interspecific variation in larval gregariousness. To assess intraspecific variation in this trait, we characterized aggregative tendency within a single widespread species, the redheaded pine sawfly (N. lecontei). To do so, we developed a quantitative assay in which we measured interindividual distances over a 90-min video. This assay revealed minimal behavioral differences: (1) between early-feeding and late-feeding larval instars, …


Phylogenetic And Ecological Analysis Of Two Populations Of The Kitsatchie Painted Crayfish, Orconectes Maletae (Decapoda: Cambaridae), Larrimy Beth Brown 2017 University of Texas at Tyler

Phylogenetic And Ecological Analysis Of Two Populations Of The Kitsatchie Painted Crayfish, Orconectes Maletae (Decapoda: Cambaridae), Larrimy Beth Brown

Biology Theses

The primary aim of this study was to assess the conservation status of the East Texas population of the Kistachie Painted Crayfish, Orconectes maletae. Orconectes maletae has been given a Global Heritage Ranking of G2, or imperiled, because of population declines in the Kisatchie Bayou drainage in Louisiana; however, similar data for Texas is lacking. For the current study, surveys of 25 historical sites in Texas were conducted in the Cypress Creek and Caddo Lake drainage from June to August 2014 and revealed that O. maletae was either absent or in low enough abundance to evade detection at close …


Trap-Neuter-Return Programs And The Importance Of Associated Public Awareness, Nicolette Sliwa 2017 Augustana College, Rock Island Illinois

Trap-Neuter-Return Programs And The Importance Of Associated Public Awareness, Nicolette Sliwa

Biology: Student Scholarship & Creative Works

The focus of this paper is to describe a typical Trap-Neuter-Return (TNR) program and highlight the major pros and cons surrounding this somewhat controversial method of managing the overwhelming free-roaming cat population. The effects of the species’ overabundance on the environment and human health are also discussed. Citing studies completed on TNR programs around the globe as well as mathematical models, the effectiveness of this method is compared to other, currently used alternatives. Finally, it has been suggested that the general awareness level a neighborhood possesses about the true goals of TNR programs has a potentially significant impact on the …


Development Of A Wild Infant Woolly Monkey Social Interactions, Time Allocation And Behavior Of A Wild Lagothrix Lagotricha Poeppigii Infant And Her Mother, Saba Zewdie 2017 SIT Study Abroad

Development Of A Wild Infant Woolly Monkey Social Interactions, Time Allocation And Behavior Of A Wild Lagothrix Lagotricha Poeppigii Infant And Her Mother, Saba Zewdie

Independent Study Project (ISP) Collection

The lowland woolly monkey (Lagothrix lagotricha poeppigii), like all species of woolly monkey, is extremely threatened due to anthropologic activities such as deforestation, petroleum drilling and commercial hunting across their habitat. Due to their low reproductive rate and low reproductive success in captivity, the captive population is decreasing every year as habitat loss increases. In late February of 2017 an infant female was born on the island of Sumak Allpa, a monkey rehabilitation organization and reserve in the western Ecuadorian Amazon. The woolly monkeys are completely independent on the reserve; and as such her birth marks the first …


What, Where, Why: A Survey Of Felidae Populations At Enashiva Nature Refuge, Tanzania, Lucrecia Aguilar 2017 SIT Study Abroad

What, Where, Why: A Survey Of Felidae Populations At Enashiva Nature Refuge, Tanzania, Lucrecia Aguilar

Independent Study Project (ISP) Collection

As felid populations worldwide continue to deteriorate due to human activities, understanding how felid species utilize various landscapes, along with what factors affect such use or disuse, becomes essential to the preservation of these species. While previous research has examined felid populations around the world, many species and locations remain understudied. This study surveyed felid species at Enashiva Nature Refuge (ENR) in the Serengeti-Mara ecosystem to determine (1) what felid species are present at ENR, (2) where these species generally occur, and (3) why felids reside at ENR in low or high numbers. Through the use of opportunistic camera trapping, …


Monitoring Anuran Populations In Bosque Protector Candelaria: A Multi-Year Comparison Of Frog Populations In An Ecuadorian Cloud Forest, Mindee Goodrum 2017 SIT Study Abroad

Monitoring Anuran Populations In Bosque Protector Candelaria: A Multi-Year Comparison Of Frog Populations In An Ecuadorian Cloud Forest, Mindee Goodrum

Independent Study Project (ISP) Collection

For many years, amphibian populations around the world have been declining due to climate change, habitat loss or change, and diseases such as Ranavirus or the Chytrid fungus. However, there is still a great lack of information regarding the diversity of frogs, especially in the cloud forests of Ecuador where this study was conducted. This study was conducted in April and May of 2017 in the Ecominga Reserve of Cerro Candelaria in El Placer, Ecuador. The objective was to conduct visual-encounter surveys of several sites in the reserve and compare the results to studies that have been conducted in the …


Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone 2017 Old Dominion University

Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone

Virginia Journal of Science

We used monthly live trapping for 2.5 years to evaluate the life-history features of the most common small mammal, Sigmodon hispidus (hispid cotton rat), in an old field at its northern limit of distribution on the Atlantic Coast. Peak densities, achieved in late autumn or early winter, were among the highest recorded for the species and were more typical of geographically marginal populations rather than of central ones. Unlike some other marginal populations, hispid cotton rats in southeastern Virginia did not lose significant body mass over the winter (when few juveniles were present) and survival in winter was not significantly …


A Reexamination The Freshwater Mussels (Family Unionidae) In Lower Big Walnut Creek, Kierra M. Lathrop 2017 Otterbein University, Ohio

A Reexamination The Freshwater Mussels (Family Unionidae) In Lower Big Walnut Creek, Kierra M. Lathrop

Undergraduate Distinction Papers

Freshwater mussels (family Unionidae) have become increasingly rare as the threats to water quality, habitat quality, and other aquatic animals, which the mussels depend on, have increased. The absence of mussels can provide evidence that one of these factors is insufficient. Lower Big Walnut Creek (BWC) is known to support a diverse community of mussels but they are unevenly distributed throughout the creek with abundance, density, and richness being high in the upper section, very low in the midsection, and intermediate in the lower section. It has been suggested water quality nor symbiotic fish host communities are responsible for this …


The North American Whistling-Ducks, Pochards, And Stifftails, Paul A. Johnsgard 2017 University of Nebraska - Lincoln

The North American Whistling-Ducks, Pochards, And Stifftails, Paul A. Johnsgard

Zea E-Books Collection

Although the 12 species representing three waterfowl tribes described in this volume are not closely related, they fortuitously provide an instructive example of adaptive evolutionary radiation within the much larger waterfowl lineage (the family Anatidae), especially as to their divergent morphologies, life histories, and social behaviors.

The whistling-ducks (Dendrocygna), with three known North American species, are notable for their permanent pair-bonds, extended biparental family care, and strong social cohesion. In contrast, males of the five typical pochards of North American diving ducks (Aythya) establish monogamous pair-bonds that are maintained only long enough to assure that the female’s eggs are fertilized. …


Patterns In Greater Sage-Grouse Population Dynamics Correspond With Public Grazing Records At Broad Scales, Adrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. Casazza 2017 Colorado State University

Patterns In Greater Sage-Grouse Population Dynamics Correspond With Public Grazing Records At Broad Scales, Adrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. Casazza

Wildland Resources Faculty Publications

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004-2014, we modeled population trends in response to grazing level (represented by a relative grazing index) …


Hitching A Ride: First Record Of A Least Chipmunk (Tamias Minimus) In Eastern Nebraska, Keith Geluso, Michael L. Forsberg 2017 University of Nebraska—Kearney

Hitching A Ride: First Record Of A Least Chipmunk (Tamias Minimus) In Eastern Nebraska, Keith Geluso, Michael L. Forsberg

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

On 10 October 2016, a Least Chipmunk (Tamias minimus) was discovered in a residential area of Lincoln, Lancaster County, Nebraska. The closest populations of Least Chipmunks reside > 640 km to the west in northwestern Nebraska and southeastern Wyoming. The most parsimonious explanation for this unusual observation is that the chipmunk was transported to the city by humans. A likely scenario is that the chipmunk hitched a ride to Lincoln in a motor vehicle on 2 October 2016, when one of us drove 1500 km in a single day from Jackson, Teton County, Wyoming, after residing in that area …


Biotic And Abiotic Factors Predicting The Global Distribution And Population Density Of An Invasive Large Mammal, Jesse S. Lewis, Mathew L. Farnsworth, Christopher L. Burdett, David M. Theobald, Miranda Gray, Ryan S. Miller 2017 Conservation Science Partners, Fort Collins, CO

Biotic And Abiotic Factors Predicting The Global Distribution And Population Density Of An Invasive Large Mammal, Jesse S. Lewis, Mathew L. Farnsworth, Christopher L. Burdett, David M. Theobald, Miranda Gray, Ryan S. Miller

Other Publications in Wildlife Management

Biotic and abiotic factors are increasingly acknowledged to synergistically shape broad-scale species distributions. However, the relative importance of biotic and abiotic factors in predicting species distributions is unclear. In particular, biotic factors, such as predation and vegetation, including those resulting from anthropogenic land-use change, are underrepresented in species distribution modeling, but could improve model predictions. Using generalized linear models and model selection techniques, we used 129 estimates of population density of wild pigs (Sus scrofa) from 5 continents to evaluate the relative importance, magnitude, and direction of biotic and abiotic factors in predicting population density of an invasive large mammal …


Subterranean Systems Provide A Suitable Overwintering Habitat For Salamandra Salamandra, Monika Balogová, Dušan Jelić, Michaela Kyselová, Marcel Uhrin 2017 P. J. Šafárik University

Subterranean Systems Provide A Suitable Overwintering Habitat For Salamandra Salamandra, Monika Balogová, Dušan Jelić, Michaela Kyselová, Marcel Uhrin

International Journal of Speleology

The fire salamander (Salamandra salamandra) has been repeatedly noted to occur in natural and artificial subterranean systems. Despite the obvious connection of this species with underground shelters, their level of dependence and importance to the species is still not fully understood. In this study, we carried out long-term monitoring based on the capture-mark-recapture method in two wintering populations aggregated in extensive underground habitats. Using the POPAN model we found the population size in a natural shelter to be more than twice that of an artificial underground shelter. Survival and recapture probabilities calculated using the Cormack-Jolly-Seber model were very …


Estimating Seasonal Variation In Condition Of Yellow Perch, Emily Anne Powers 2017 Bemidji State University

Estimating Seasonal Variation In Condition Of Yellow Perch, Emily Anne Powers

Biology Graduate Theses

Research has shown that Yellow Perch Perca flavescens, found throughout lakes and streams of North America, are good indicators of environmental health. Due to the correlation between fish condition and ecosystem health it is essential to reliably estimate condition to better manage our fisheries. Therefore, the study objectives were to measure the seasonal changes in adult Yellow Perch percent dry weight (PDW), and compare the reliability of bioelectrical impedance analysis (BIA) and morphometric-based estimates of condition. The seasonal fluctuations in average monthly PDW were measured over a two- year period and were sinusoidal in shape with peaks in August 2015 …


2016 Christmas Bird Counts, Don Paseka 2017 Nebraska Ornithologists' Union

2016 Christmas Bird Counts, Don Paseka

Nebraska Bird Review

Fourteen Nebraska counts were held during the 2016 CBC season, which is one less than last year. The Harrison and Crawford counts were cancelled this year, but in the opposite corner of the state, a new count was started that includes Indian Cave State Park. An unusually mild November and a seasonable start to December were followed by a modest cold snap during the second week of the month. The Harlan County count was run early in the period on the 15th with ample open water, and it produced a record number of species (90) for that circle. But in …


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