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Molecular And Evolutionary Analysis Of Cyanobacterial Taxonomic Methods, Chelsea Denise Villanueva 2018 University of North Florida

Molecular And Evolutionary Analysis Of Cyanobacterial Taxonomic Methods, Chelsea Denise Villanueva

UNF Graduate Theses and Dissertations

Cyanobacteria are a group of photo-oxygenic bacteria found in nearly every ecosystem, but much cyanobacterial diversity, in various habitats, has yet to be explored. Cyanobacteria are often conspicuous components of photosynthetic flora, providing significant carbon and nitrogen inputs to surrounding systems. As possible primary colonizers of stone substrates not native to this region, cyanobacteria isolated from headstones may provide biogeographically informative data. An exploratory study of lichen-dominated microbial consortia, growing on headstones, was conducted to isolate and identify novel microaerophytic cyanobacteria, and resulted in the establishment of four novel cyanobacterial taxa. Phylogenetic analyses of photobionts in one tripartite lichen revealed …


Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind 2018 Virginia Commonwealth University

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …


Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi 2018 Michigan Technological University

Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi

Dissertations, Master's Theses and Master's Reports

Cladophora glomerata is a filamentous green alga native to the Great Lakes. However, its nuisance growth in phosphorus rich waters negatively affects the lakes’ aesthetic and water quality. The Great Lakes Cladophora Model (GLCM) v1, developed in 1982, was the first mechanistic model to simulate Cladophora growth basing phosphorus availability and environmental conditions followed by Cladophora Growth Model and GLCM v2. In this study, the light and temperature mediation factors for Cladophora net growth are revised as a necessary step prior to the development of a self-shading algorithm. The concept of a fixed-value, maximum achievable biomass (carrying capacity) employed in …


Intraspecific Genetic Variation, Population Structure, And Performance Of The Invasive Aquatic Macrophyte Eurasian Watermilfoil (Myriophyllum Spicatum) In Waterbodies With And Without Histories Of Chemical Herbicide Treatment Across Michigan, Taylor Zallek 2018 Michigan Technological University

Intraspecific Genetic Variation, Population Structure, And Performance Of The Invasive Aquatic Macrophyte Eurasian Watermilfoil (Myriophyllum Spicatum) In Waterbodies With And Without Histories Of Chemical Herbicide Treatment Across Michigan, Taylor Zallek

Dissertations, Master's Theses and Master's Reports

Populations of invasive species are often subjected to novel selective forces in the form of anthropogenic control agents in their introduced ranges. These control agents, applied unevenly among populations within a species’ new range, can send invasive populations on drastically different evolutionary and ecological trajectories. In these studies, we aimed to see if different histories of chemical herbicide treatment are differentially influencing the genetic diversity, structure, and performance of populations of invasive watermilfoil (Myriophyllum spicatum and M. spicatum x M. sibiricum hybrids) from waterbodies in the state of Michigan. We sampled ten waterbodies with different histories of herbicide treatment …


Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon 2018 Georgia Southern University

Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon

College of Graduate Studies: Theses & Dissertations

Rivers and streams provide essential ecosystem services to the degree that the monitoring and maintenance of these systems becomes imperative. Biomonitoring provides managers and policymakers with the tools to make informed decisions, and macroinvertebrates are often the object of biomonitoring because they are ubiquitous in most systems and are known to be good indicators of water quality. However, methods for sampling macroinvertebrates in non-wadeable streams (i.e., large rivers) have not been standardized across states and regions and an established method for macroinvertebrate biomonitoring in large rivers of Georgia is not currently available. My study compared macroinvertebrates collected with three types …


A Comparison Of Two Methods Of Quantifying Mating Success In Low Density Gypsy Moth (Lymantria Dispar) Populations, Alexandra Barry, Hannah Byrne, Derek M. Johnson 2018 Virginia Commonwealth University

A Comparison Of Two Methods Of Quantifying Mating Success In Low Density Gypsy Moth (Lymantria Dispar) Populations, Alexandra Barry, Hannah Byrne, Derek M. Johnson

UROP Posters

The gypsy moth (Lymantria dispar) is a defoliating pest native to Europe and invasive to North America. The gypsy moth is subject to depressed mating success in low density populations, which may restrict spread of the forest pest. Research focusing on gypsy moth density as it relates to mating behavior has often used counts of males caught in pheromone-baited delta traps as a proxy to estimate the probability of female mating success. The purpose of this project was to determine whether pheromone trap counts provide accurate estimates of female mating success probability, by comparing data gathered from pheromone-baited …


Characterizing The Complex Relationship Between The Brown Widow Spider And Its Bacterial Endosymbiont, Wolbachia, Emily Knight 2018 Georgia Southern University

Characterizing The Complex Relationship Between The Brown Widow Spider And Its Bacterial Endosymbiont, Wolbachia, Emily Knight

College of Graduate Studies: Theses & Dissertations

The brown widow spider, Latrodectus geometricus (C. L. Koch 1841), has been found to harbor the maternally inherited bacterial endosymbiont Wolbachia pipientis (Hertig and Wolbach 1924), but endosymbiont infection frequency varies widely among Southeastern US populations. Wolbachia is known to manipulate the reproduction of its hosts through male feminization, parthenogenesis, male killing, and cytoplasmic incompatibility. In brown widows, Wolbachia does not alter sex ratios, but any other effects the symbiont has on the spider are unknown. In my first chapter, I assess if there is linkage between Wolbachia infection and maternally inherited mitochondrial DNA (mtDNA) in three brown widow populations. …


Foraging Ecology Of A Winter Bird Community In Southeastern Georgia, Rachel E. Mowbray 2018 Georgia Southern University

Foraging Ecology Of A Winter Bird Community In Southeastern Georgia, Rachel E. Mowbray

College of Graduate Studies: Theses & Dissertations

Classical views on community structure emphasized deterministic processes and the importance of competition in shaping communities. However, the processes responsible for shaping avian communities remain controversial. Attempts to understand distributions and abundances of species are complicated by the fact that birds are highly mobile. Many species migrate biannually between summer breeding grounds and wintering grounds. The goal of this study was to test four hypotheses that attempt to explain how migratory species integrate into resident assemblages of birds (Empty-Niche Hypothesis, Competitive-Exclusion Hypothesis, Niche-Partitioning Hypothesis, and Generalist-Migrant Hypothesis). I collected data on birds foraging during the winter of 2017-2018 in Magnolia …


Population-Level Plasticity In Foraging Behavior Of Western Gulls (Larus Occidentalis), Scott A. Shaffer, Sue Cockerham, Pete Warzybok, Russell Bradley, Jaime Jahncke, Corey Clatterbuck, Magali Lucia, Jennifer Jelincic, Anne Cassell, Emma Kelsey, Josh Adams 2017 San Jose State University

Population-Level Plasticity In Foraging Behavior Of Western Gulls (Larus Occidentalis), Scott A. Shaffer, Sue Cockerham, Pete Warzybok, Russell Bradley, Jaime Jahncke, Corey Clatterbuck, Magali Lucia, Jennifer Jelincic, Anne Cassell, Emma Kelsey, Josh Adams

Faculty Publications, Biological Sciences

Background Plasticity in foraging behavior among individuals, or across populations may reduce competition. As a generalist carnivore, western gulls (Larus occidentalis) consume a wide range of marine and terrestrial foods. However, the foraging patterns and habitat selection (ocean or land) of western gulls is not well understood, despite their ubiquity in coastal California. Here, we used GPS loggers to compare the foraging behavior and habitat use of western gulls breeding at two island colonies in central California. Results Gulls from offshore Southeast Farallon Island (SFI; n = 41 gulls) conducted more oceanic trips (n = 90) of …


Of Rats And Men, Thomas S. Walsh 2017 Cuny Graduate School of Journalism

Of Rats And Men, Thomas S. Walsh

Capstones

This capstone is a data-driven investigation into New York City's rat problem. By using publicly available government data to map rat activity in NYC, I identified several socio-economic variables that correlate with rat populations at the community district, borough, and city-scale. I used these findings (mainly that rat problems are linked to lower incomes) as the basis of an investigation, which includes interviews with residents, experts, and city officials. Prof. Bobby Corrigan, urban rodentologist and formerly with the NYC Department of Health criticizes the city's efforts for the first time on the record.

https://thomasseiyawalsh.wixsite.com/ratstone


Seasonal Resource Selection And Habitat Treatment Use By A Fringe Population Of Greater Sage-Grouse, Rhett Boswell 2017 Utah State University

Seasonal Resource Selection And Habitat Treatment Use By A Fringe Population Of Greater Sage-Grouse, Rhett Boswell

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Movement and habitat selection by Greater Sage-grouse (Centrocercus uropasianus) is of great interest to wildlife managers tasked with applying conservation measures for this iconic western species. Current technology has created small and lightweight GPS (Global Positioning Systems) transmitters that can be attached to sage-grouse. Using GIS software and statistical programs such as Program R, land managers can analyze GPS location data to assess how sage-grouse are geospatially interacting with their habitats. Within the Panguitch Sage-Grouse Management Area (SGMA) thousands of acres of land have been restored or manipulated to enhance sage-grouse habitat; this usually involves removal of pinyon pine …


The Behavioural Response Of Migrating Humpback Whales To A Full Seismic Airgun Array, Rebecca A. Dunlop, Michael J. Noad, Robert D. McCauley, Eric Kniest, Robert Slade, David Paton, Douglas H. Cato 2017 University of Queensland

The Behavioural Response Of Migrating Humpback Whales To A Full Seismic Airgun Array, Rebecca A. Dunlop, Michael J. Noad, Robert D. Mccauley, Eric Kniest, Robert Slade, David Paton, Douglas H. Cato

Anthropogenics and Population Decline Collection

Despite concerns on the effects of noise from seismic survey airguns on marine organisms, there remains uncertainty as to the biological significance of any response. This study quantifies and interprets the response of migrating humpback whales (Megaptera novaeangliae) to a 3130 in3 (51.3l) commercial airgun array. We compare the behavioural responses to active trials (array operational; n = 34 whale groups), with responses to control trials (source vessel towing the array while silent; n = 33) and baseline studies of normal behaviour in the absence of the vessel (n = 85). No abnormal behaviours were recorded …


Homogenization Techniques For Population Dynamics In Strongly Heterogeneous Landscapes, Brian P. Yurk, Christina A. Cobbold 2017 Hope College

Homogenization Techniques For Population Dynamics In Strongly Heterogeneous Landscapes, Brian P. Yurk, Christina A. Cobbold

Faculty Publications

An important problem in spatial ecology is to understand how population-scale patterns emerge from individual-level birth, death, and movement processes. These processes, which depend on local landscape characteristics, vary spatially and may exhibit sharp transitions through behavioural responses to habitat edges, leading to discontinuous population densities. Such systems can be modelled using reaction–diffusion equations with interface conditions that capture local behaviour at patch boundaries. In this work we develop a novel homogenization technique to approximate the large-scale dynamics of the system. We illustrate our approach, which also generalizes to multiple species, with an example of logistic growth within a periodic …


Effects Of Trophic Relationships On Oyster Reef Restoration Success In The Mississippi Sound, Virginia Robin Fleer 2017 University of Southern Mississippi

Effects Of Trophic Relationships On Oyster Reef Restoration Success In The Mississippi Sound, Virginia Robin Fleer

Dissertations

Natural and anthropogenic changes resulting from altered hydrology, hurricanes, variable precipitation, and the BP oil spill have all taken their toll on oyster reefs in Mississippi. In response, oyster reef restoration efforts are currently underway within the Northern Gulf of Mexico. In order to understand why these efforts succeed or fail, it is crucial to consider predator-prey relationships within the context of the trophic dynamics of oyster reefs. Thus, for this dissertation study I integrated a multidisciplinary approach to understanding key trophic interactions affecting oyster recruitment, growth and survival, comprising field sampling, manipulative lab experiments, and individual-based modeling. Spat settlement …


The Official List Of The Birds Of Nebraska, Mark A. Brogie 2017 Nebraska Ornithologists' Union

The Official List Of The Birds Of Nebraska, Mark A. Brogie

Nebraska Bird Review

The last published “Official List” of the NOURC (NOURC 2009) included 454 species. Since then the following species have been added:

Brown-headed Nuthatch (Sitta pusilla) Accidental I-P 2010

Hooded Crane (Grus monacha) Accidental I-P 2011

Crested Caracara (Caracara cheriway) Accidental I-P 2012

Black-chinned Hummingbird (Archilochus alexandri) Casual I-P 2012

Hooded Oriole (Icterus cucullatus) Accidental I-P 2013

Brown Booby (Sula leucogaster) Accidental I-P 2014

Mute Swan (Cygnus olor) Accidental I-P 2014

Anna’s Hummingbird (Calypte anna) Accidental I-P 2016

Pacific Wren (Troglodytes pacificus) Accidental I-P 2017


The Nebraska Bird Review, Volume 85 December 2017 Number 4, 2017 University of Nebraska - Lincoln

The Nebraska Bird Review, Volume 85 December 2017 Number 4

Nebraska Bird Review

Fall Field Report, August - November 2017, by W. Ross Silcock … 146-178

The Official List of the Birds of Nebraska, compiled by Mark A. Brogie …179-197

Ogallala Fall Field Days, Sept. 15 - 17, 2017, by Janis Paseka …198-203

Index to Volume 85 …204-218

Subscription and Organization Information … 219


Index To Volume 85, 2017 University of Nebraska - Lincoln

Index To Volume 85

Nebraska Bird Review

Abreu, Shanin 58 ...

through

Ziegelbauer, Amanda 147

(15 pages)


Fall Field Report, August - November 2017, W. Ross Silcock 2017 Nebraska Ornithological Union

Fall Field Report, August - November 2017, W. Ross Silcock

Nebraska Bird Review

This fall season will be remembered as the fall with the mega-rarities. There were five, one of which, Pacific Wren, is a first Nebraska record. Based on occurrence dates, Hurricane Irma appears to have influenced the appearance of two of the megas, Black Vulture and Magnificent Frigatebird, neither of which provided opportunities for observers to view them, but both well-documented with photographs. There were an extraordinary TWO sightings of Harris’s Hawk, which together with the presence as of this writing (December 19) of one in northeast Kansas and a view of the species map in eBird strongly suggest a single …


Ogallala Fall Field Days, Sept. 15 - 17, 2017, Janis Paseka 2017 Nebraska Ornithologists’ Union

Ogallala Fall Field Days, Sept. 15 - 17, 2017, Janis Paseka

Nebraska Bird Review

The 2017 NOU Fall Field Days took place in and around Ogallala on Sept. 15 - 17 with 55 in attendance. The weather on Friday was hot and windy, making finding birds a challenge. Overnight a cold front came through causing birders to shiver on Saturday and Sunday mornings, but the payoff was easier birding and some interesting species. Field trips were led by William Flack, Clem Klaphake, Wayne Mollhoff, Don Paseka, Ross Silcock and T. J. Walker. Locations included Cedar Point Biological Station, Lake Ogallala SRA, various beaches along the shore of Lake McConaughy SRA, Ash Hollow State Historical …


Biological Condition Of Money Pont Benthic Communities, Southern Branch Of The Elizabeth River (2010, 2013, 2016), Daniel M. Dauer 2017 Old Dominion University

Biological Condition Of Money Pont Benthic Communities, Southern Branch Of The Elizabeth River (2010, 2013, 2016), Daniel M. Dauer

Elizabeth River Reports

Executive Summary

This report summarizes the ecological condition of the subtidal macrobenthic communities off Money Point in the Southern Branch of the Elizabeth River based upon quantitative sampling in summer 2016. The designated Money Point study area was part of a sediment contaminant remediation effort. The primary objectives were to: (1) characterize the biological health of the benthos of Money Point comparing pre-remediation condition (2010) to post-remediation condition in 2013 and again in 2016, and (2) assess the effectiveness of the sediment contamination remediation efforts with respect to the ecological condition of the Money Point benthos.

Prior to sediment contaminant …


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