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Artificial Intelligence System For Automatic Imaging, Quantification, And Identification Of Arthropods In Leaf Litter And Pitfall Samples, Pierce Helton, Khoa Luu, Ashley Dowling Jan 2022

Artificial Intelligence System For Automatic Imaging, Quantification, And Identification Of Arthropods In Leaf Litter And Pitfall Samples, Pierce Helton, Khoa Luu, Ashley Dowling

Inquiry: The University of Arkansas Undergraduate Research Journal

It is well known that arthropods are the most diverse and abundant eukaryotic organisms on the planet. Museum and research collections have huge insect accumulations from expeditions conducted over history that contain specimens of both temporal and spatial value, including hundreds of thousands of species. This biodiversity data is inaccessible to the research community, resulting in a vast amount of “dark data”. The primary objective of this study is to develop an artificial intelligence-driven system for specimen identification that greatly minimizes the time and expertise required to identify specimens in atypical environments. Successful development will have profound impacts on both …


Effects Of Drought On Habitat Quality For Native Bees In Residential Gardens Of Claremont, Ca, Max Proctor Jan 2022

Effects Of Drought On Habitat Quality For Native Bees In Residential Gardens Of Claremont, Ca, Max Proctor

CMC Senior Theses

Over 1,500 of the 4000 bee species found in North America inhabit California. Native bees are declining however, largely due to climate change and agricultural intensification. Previous research shows that cities can sustain diverse bee communities, due to the diversity of ornamental flowers. Urban green space represents an opportunity for native bee conservation. Residential gardens provide lots of green space and are urban pollinator hotspots. Managing yards for increased floral resources and nesting habitat can benefit native bee communities. Turfgrass provides few floral or nesting resources and negatively correlates with bee diversity. The 2011-2017 California drought caused many homeowners to …


Spatial And Temporal Heterogeneity Of Hyporheic Invertebrates In An Ozark Stream, David Fleshman Jan 2022

Spatial And Temporal Heterogeneity Of Hyporheic Invertebrates In An Ozark Stream, David Fleshman

Graduate Theses/Dissertations

The hyporheic zone (HZ), an ecotone between surface water and groundwater in streams, provides extensive but underappreciated habitat for invertebrates in alluvial systems like the gravel-bed streams common in the Ozark highlands. Relative to its importance as a habitat, little is known about spatial distribution and response to disturbance by invertebrates in the HZ. In riffle-pool systems, surface water typically enters the HZ at the head of riffles (downwelling) and returns to the surface at the tail of riffles (upwelling). Previous research has found differences in invertebrate communities and environmental variables between upwelling and downwelling zones, but results have been …


Effects Of Snake Fungal Disease On The Survival And Growth Of The Queensnake (Regina Septemvittata), Andrew Jerome Ibach Jan 2022

Effects Of Snake Fungal Disease On The Survival And Growth Of The Queensnake (Regina Septemvittata), Andrew Jerome Ibach

Theses and Dissertations--Forestry and Natural Resources

Having only emerged as a threat to snakes in 2006, relatively little is known of snake fungal disease’s (SFD) impacts on demographic processes, particularly survival and growth. I used data from an extensive capture-mark-recapture study to examine survival and growth in central Kentucky Queensnake (Regina septemivittata) populations. I found that diseased snakes and healthy snakes possessed similar monthly survival estimates (SFD positive 0.9687, 95% CI 0.8444 to 0.9944; SFD negative 0.8735, 95% CI 0.7518 to 0.9402) and that disease state transition probability from SFD negative to SFD positive, and SFD positive to SFD negative were also similar (N-P …


Effects Of Unpaved Roads On Relative Abundance And Epigenetics Of Early Successional Lizards, David Tevs Jan 2022

Effects Of Unpaved Roads On Relative Abundance And Epigenetics Of Early Successional Lizards, David Tevs

College of Graduate Studies: Theses & Dissertations

Unpaved roads may provide uniform microhabitat characteristics and impart edge effects in the adjacent landscape that mediate environmental pressures acting on small vertebrates. These features may allow species that are associated with recent disturbance to persist in aging forest patches. Further, epigenetic mechanisms such as DNA methylation may provide these species the phenotypic plasticity necessary to occupy multiple habitats with different environmental conditions. To understand how small vertebrates use unpaved roads, the relative abundance and occurrence of Florida scrub lizards (Sceloporus woodi) and six-lined racerunners (Aspidoscelis sexlineata) were quantified using visual encounter surveys along unpaved roads …


Potential Effects Of Amynthas Agrestis Invasion On Woody Understory Flora In The Cvnp, Christian Mammana Jan 2022

Potential Effects Of Amynthas Agrestis Invasion On Woody Understory Flora In The Cvnp, Christian Mammana

Williams Honors College, Honors Research Projects

Ohio forests are threatened by the invasive ecosystem engineer A. agrestis. A. agrestis invasion typically co-occurs with the ecosystem engineer, Odocoileus virginianus, where their impacts may synergize. To determine the direct effects of A. agrestis invasion, fenced plots across the Cuyahoga Valley National Park that excluded deer were utilized. The species richness, Shannon diversity and evenness of woody understory flora was measured in each plot. Mustard extraction was used to determine earthworm abundance. Correlations between abundance and measured variables were used to highlight potential invasion effects. Abundance and species richness was found to have a significant, positive correlation (p = …


Industrial Hemp As A Resource For Birds In Agroecosystems: Human-Wildlife Conflict Or Conservation Opportunity?, Emily A. Kotten, Iona Hennessy, Bryan M. Kluever, Bradley F. Blackwell, Lee A. Humberg, Page E. Klug Jan 2022

Industrial Hemp As A Resource For Birds In Agroecosystems: Human-Wildlife Conflict Or Conservation Opportunity?, Emily A. Kotten, Iona Hennessy, Bryan M. Kluever, Bradley F. Blackwell, Lee A. Humberg, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and …


Quantifying Contributions Of Climate, Geography, And Gene Flow To Divergence: A Case Study For Three North American Pines, Constance E. Bolte Jan 2022

Quantifying Contributions Of Climate, Geography, And Gene Flow To Divergence: A Case Study For Three North American Pines, Constance E. Bolte

Theses and Dissertations

Long-lived species of trees, especially conifers, often display weak patterns of reproductive isolation, but clear patterns of local adaptation and phenotypic divergence. Discovering the evolutionary history of these patterns is paramount to a generalized understanding of speciation and the processes that confer population persistence versus those that compromise adaptive potential under rapidly changing environments. Forest trees have long generation times and low migratory potential making them especially vulnerable to population fragmentation and reductions of genetic diversity due to insufficient tracking of niche optima and adaptational lags. Within clades of the genus Pinus, evolutionary histories appear to be riddled with hybridization …


An Examination Of Ethical Attitudes Towards Wild Pig (Sus Scrofa) Toxicants In The United States, Keith Carlisle, Erin E. Harper, Stephanie A. Shwiff Jan 2022

An Examination Of Ethical Attitudes Towards Wild Pig (Sus Scrofa) Toxicants In The United States, Keith Carlisle, Erin E. Harper, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

This research aims to understand ethical attitudes of the U.S. public towards the use of a toxicant to control wild pigs (Sus scrofa), a destructive invasive species whose population growth is proving difficult to control through conventional management methods. Using a nationwide self-administered survey with 2,186 completed and returned questionnaires, we found that among six different lethal control methods, toxicant usage was the only method that a majority of respondents (51%) found to be unethical, with no significant differences between rural and urban respondents or between respondents from counties with wild pigs and counties where the species is absent. The …


A Systematic Map Of Human-Carnivore Coexistence, Cassandre C. Venumière-Lefebvre, Stewart W. Breck, Kevin R. Crooks Jan 2022

A Systematic Map Of Human-Carnivore Coexistence, Cassandre C. Venumière-Lefebvre, Stewart W. Breck, Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

Carnivore populations globally have largely declined, and coexistence, where humans and carnivores share landscapes, plays a crucial role in carnivore conservation. However, the term “coexistence” is often used in scientific and popular literature without being clearly defined. Herein, we provide a global perspective on what coexistence is and how it is studied. We conducted a systematic map of 366 articles published between 1987 and 2020 to characterize human-carnivore coexistence literature according to coexistence definitions, temporal trends, geographic and taxonomic focus, and four thematic aspects of coexistence: carnivore ecology, human endeavors, social conflict and human-carnivore conflict. We used chi-squared tests and …


Predicting Consistent Foraging Ecologies Of Migrating Waterbirds: Using Stable Isotope And Parasite Measurements As Indicators Of Landscape Use, Kate L. Sheehan, Brian S. Dorr, Stephen A. Clements, Terrel W. Christie, Katie Hanson-Dorr, Scott A. Rush, J. Brian Davis Jan 2022

Predicting Consistent Foraging Ecologies Of Migrating Waterbirds: Using Stable Isotope And Parasite Measurements As Indicators Of Landscape Use, Kate L. Sheehan, Brian S. Dorr, Stephen A. Clements, Terrel W. Christie, Katie Hanson-Dorr, Scott A. Rush, J. Brian Davis

United States Department of Agriculture Wildlife Services: Staff Publications

The emergence of novel human pathogens is frequently linked with zoonotic events and human-wildlife interactions that promote disease transmission. Consequently, surveillance of wildlife populations for candidate diseases that could spread to humans is beneficial, but requires widespread collections of numerous samples. A legitimate means to acquire large sample sizes of waterfowl is through cooperation between researchers and hunters, who also work in concert with natural resource managers, landowners, and agricultural entities -e.g., aquaculture facilities. In addition to understanding the occurrence and spread of parasites and pathogens by birds, these samples can be used to answer questions about the ecology of …


Cover, Editorial Staff, Journal Information Jan 2022

Cover, Editorial Staff, Journal Information

Human–Wildlife Interactions

This includes the cover, editorial staff, and journal information.


Texas Hunters’ Perceptions Regarding The Acceptability Of Toxicants To Control Wild Pig Populations, Keith M. Carlisle, Sophie Mckee, Hailey E. Ellis, Lauren M. Jaebker, John M. Tomeček, Alan D. Bright, Rachael L. Connally, Maureen G. Frank, Stephanie A. Shwiff Jan 2022

Texas Hunters’ Perceptions Regarding The Acceptability Of Toxicants To Control Wild Pig Populations, Keith M. Carlisle, Sophie Mckee, Hailey E. Ellis, Lauren M. Jaebker, John M. Tomeček, Alan D. Bright, Rachael L. Connally, Maureen G. Frank, Stephanie A. Shwiff

Human–Wildlife Interactions

Wild pigs (Sus scrofa) are an invasive species in the United States. They damage agriculture, degrade water quality and ecological communities, and host a number of viruses, parasites, and bacteria transmissible to humans and animals. In states such as Texas, USA, where wild pigs cause extensive damage to agriculture and property, officials have considered allowing for the use of toxicants to control wild pig populations. To provide decision-makers with information regarding stakeholders’ perceptions of the use of toxicants to control wild pigs, we surveyed Texas hunters in 2019 to assess the level of acceptance of a hypothetical wild …


Cover, Editorial Staff, Journal Information Jan 2022

Cover, Editorial Staff, Journal Information

Human–Wildlife Interactions

This includes the cover, editorial staff, and journal information.


Quantifying Wildlife Use Of Escape Ramps Along A Fenced Highway, Alex J. Jensen, John D. Perrine, Andrew A. Schaffner, Robert A. Brewster, Anthony J. Giordano, Morgan Robertson, Nancy R. Siepel Jan 2022

Quantifying Wildlife Use Of Escape Ramps Along A Fenced Highway, Alex J. Jensen, John D. Perrine, Andrew A. Schaffner, Robert A. Brewster, Anthony J. Giordano, Morgan Robertson, Nancy R. Siepel

Human–Wildlife Interactions

Wildlife exclusion fencing can significantly reduce wildlife–vehicle collisions. However, some animals breach the fence and become trapped in the highway corridor, thereby increasing risk of a wildlife–vehicle collision. An emerging solution to this problem is the installation of earthen escape ramps (i.e., jumpouts), which allow trapped animals to escape the highway corridor. Few studies have quantified wildlife use of jumpouts, and none have investigated intraspecific differences in use. We used camera traps to document wildlife use of 4 2m-high jumpouts associated with wildlife exclusion fencing along Highway 101 near San Luis Obispo, California, USA, from 2012 to 2017. We surveyed …


Cover, Editorial Staff, Journal Information Jan 2022

Cover, Editorial Staff, Journal Information

Human–Wildlife Interactions

This includes the cover, editorial staff, and journal information.


Biotic Characteristics Of Managed And Unmanaged Coastal Dunes In The Outer Banks, North Carolina, Andrew E. White Jan 2022

Biotic Characteristics Of Managed And Unmanaged Coastal Dunes In The Outer Banks, North Carolina, Andrew E. White

Theses and Dissertations

Under future climate change and sea level rise scenarios, Natural and Nature-Based Features (e.g., dunes) that protect coastal habitat and infrastructure will be exposed to increased wave energy and storm surge. Understanding how these forces will impact coastal dunes is necessary for their continued use as protective features. Coastal dunes develop through feedback between vegetation and sediment deposition, a process complicated by species-specific growth rates and responses to burial. Wave flume studies have tested the effects of dune vegetation on erosion and found multiple plant organs across several functional types to be important for resisting erosion. Although dune building and …


Applying Conservation Genomic Techniques To Guide Management Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi), Miranda Gaupp Jan 2022

Applying Conservation Genomic Techniques To Guide Management Of The Reticulated Flatwoods Salamander (Ambystoma Bishopi), Miranda Gaupp

College of Graduate Studies: Theses & Dissertations

The Reticulated flatwoods salamander (Ambystoma bishopi) is a federally endangered amphibian endemic to the longleaf-pine ecosystem of the southeastern U.S. This study used analyses of single-nucleotide polymorphism (SNP) data, collected from 2,255 unique individuals across 5 breeding seasons, spread across the known extant range of A. bishopi, to characterize the genetic diversity and demographics of populations, genetic relationships among populations, and patterns and spatial extents of gene flow, and to evaluate potential effects of management on A. bishopi’s resiliency. Population structure was strongly hierarchical, with individual breeding ponds (n = 38) acting as semi-connected subpopulations …


Deterring Non-Target Birds From Toxic Bait Sites For Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Justin A. Foster, Michael J. Lavelle, Justin W. Fischer, Michael P. Glow, Ingrid A. Messer, Seth M. Cook, Kurt C. Vercauteren Dec 2021

Deterring Non-Target Birds From Toxic Bait Sites For Wild Pigs, Nathan P. Snow, Joseph M. Halseth, Justin A. Foster, Michael J. Lavelle, Justin W. Fischer, Michael P. Glow, Ingrid A. Messer, Seth M. Cook, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Toxic baiting of wild pigs (Sus scrofa) is a potential new tool for population control and damage reduction in the US. Field trials testing a prototype toxic bait (HOGGONE 2 containing 5% sodium nitrite [SN]), though, revealed that wild pigs spilled small particles of toxic bait outside of bait stations which subsequently created hazards for non-target species that consumed those particles, primarily passerine birds. To deter non-target birds from consuming particles of spilled bait, we tested four deterrents at mock bait sites (i.e., baited with bird seed) in north-central Colorado, USA during April–May 2020. We found a programable, inflatable deterrent …


American Bullfrog (Lithobates Catesbeianus) Diet In Uruguay Compared With Other Invasive Populations In Southern South America, Gabriel Laufer, Noelia Gobel, Mauro Berazategui, Matías Zarucki, Sofía Cortizas, Alvaro Soutullo, Claudio Martinez Debat, Rafael O. De Sá Dec 2021

American Bullfrog (Lithobates Catesbeianus) Diet In Uruguay Compared With Other Invasive Populations In Southern South America, Gabriel Laufer, Noelia Gobel, Mauro Berazategui, Matías Zarucki, Sofía Cortizas, Alvaro Soutullo, Claudio Martinez Debat, Rafael O. De Sá

Biology Faculty Publications

Between 2000-2020, more than ten new populations of the invasive American bullfrog (Lithobates catesbeianus) have been reported in the southern cone of South America. We studied the stomach contents of 126 bullfrogs from a population at an early invasion stage in Uruguay (Acegua, Cerro Largo Department). We observed a rich diet, with extensive prey volume range (1 mm3 to more than 7 000 mm(3)); the most frequent items were Hymenoptera (19.6%), Coleoptera (16.4%), Amphipoda (13.3%), Anura (8.9%) and Heteroptera (8.7%). Despite some overlap, differences were observed in volume (chi(2) = 54.6, p <0.001, d.f. = 2) and prey quantity (F = 8.1, p <0.001, d.f. = 79) between males, females, and juveniles. Juveniles showed significantly higher consumption of terrestrial prey by count (82% of their total ingestion) than adults (29% for males and 32% for females) (chi(2) = 28.5, p <0.001, d.f. = 2). Adults, especially females, showed a high frequency of cannibalism (33% of their total ingestion; chi(2) = 20.9, p <0.001, d.f. = 2). Comparing our data with other bullfrog regional studies, we found great plasticity in trophic habits and differences in the incidence of cannibalism (higher incidence in the populations of Acegua, Uruguay, and Buenos Aires, Argentina). These differences could be related to local biodiversity, but also could be affected by the invasion phase. Cannibalism frequency was higher in small bullfrog populations, where it could be favoring the establishment success. This shift in foraging strategies during the invasion process had been insufficiently evaluated in amphibians. Knowing the ecological determinants for the invasion by bullfrogs can be useful to the development of management strategies.


Cognitive Ecology Of Color Vision In Orchid Bees, Andreia Queiroz Santos A Figueiredo Nov 2021

Cognitive Ecology Of Color Vision In Orchid Bees, Andreia Queiroz Santos A Figueiredo

Dissertations

Animals interact with their environment and acquire information from it. Information can be processed by their sensory systems and influence behavior, often mediated through mechanisms of decision-making and learning. Animal pollinators acquire information from flowers and use this information to make decisions about the flowers they visit. My research aimed to understand the role of color vision in a tropical pollinator, the orchid bee Euglossa dilemma. Chapter 1 is a review exploring pollination through the lens of prepared learning. Prepared learning proposes that animals learn some associations better than others due to an evolved match with the environment. I …


An Environmental Study To Adapt Some Hadhramout Coast Plant For Drought And Salinity Tolerance, Fatehia Ali Bashantoof, Ahmed Sbit Bamousy, Abdulkarim Saber Ali Nov 2021

An Environmental Study To Adapt Some Hadhramout Coast Plant For Drought And Salinity Tolerance, Fatehia Ali Bashantoof, Ahmed Sbit Bamousy, Abdulkarim Saber Ali

Hadhramout University Journal of Natural & Applied Sciences

The study was conducted between May 2016-August 2017. An auger was used to collect 60 random soil samples to carry out the physical and chemical analyses. The selected plants were Salola baryosma and Aeurops lagopoides in the salt marsh and Prosopis juliflora and Calotropis procera in the valleys. The results revealed clear physical and chemical differences within the soils of the salt marshes and valleys that prove to be sandy, loamy, basic and saline. All investigated variables differ in the selected areas e.g. % of sand, silt, clay. The soil of all the salt marshes was devoid of gravel which …


Effects Of Refuge Prey On Stability Of The Prey-Predator Model Subject To Immigrants: A Mathematical Modelling Approach, Mussa Amos Stephano, Il Hyo Jung Oct 2021

Effects Of Refuge Prey On Stability Of The Prey-Predator Model Subject To Immigrants: A Mathematical Modelling Approach, Mussa Amos Stephano, Il Hyo Jung

Tanzania Journal of Science

Prey-predator system is enormously complex and nonlinear interaction between species. Such complexity regularly requires development of new approaches which involves more factors in analysis of its population dynamics. In this paper, we formulate a modified Lotka-Volterra model that incorporates factors such as refuge prey and immigrants. We investigate the effects of refuge prey and immigrants by varying the refuge factor, with and without immigrants. The results show that with Holling’s type I functional response, the proposed model is asymptotically convergent when a refuge prey factor is introduced. Moreover, with Holling’s type II functional response, the proposed mathematical model is unstable …


Inventory And Distribution Of Mosquitoes (Diptera, Culicidae) In The Aures Region (Batna, Algeria), Nora Belkhiri, Wafa Habbachi, Saliha Benhissen, Naama Frah, Abdelmadjid Yagoub Asloum, Nadia Aberkane Oct 2021

Inventory And Distribution Of Mosquitoes (Diptera, Culicidae) In The Aures Region (Batna, Algeria), Nora Belkhiri, Wafa Habbachi, Saliha Benhissen, Naama Frah, Abdelmadjid Yagoub Asloum, Nadia Aberkane

Journal of Bioresource Management

Mosquitoes are the most terrifying both for their abundance and for the diseases they transmit. They are vectors of malaria, lymphatic filariasis and arbovirus such as yellow fever, dengue, viral encephalitis and African horse sickness. These characteristics give this fauna prominent importance and health interest. To identify the most widespread mosquito species, we conducted for the first time an inventory in the Aures region more particularly the wilaya of Batna (East of Algeria) from May 2017 to January 2020, we studied their diversity, abundance and distribution. The sampling is done by monthly surveys of the various localities chosen, using the …


Camera Trap Survey Suggests Forestry And Prescribed Burns Attract Wildlife, But May Not Enhance Diversity, Melissa S. Vilgats, Ryan Ott, Stephanie S. Coster Oct 2021

Camera Trap Survey Suggests Forestry And Prescribed Burns Attract Wildlife, But May Not Enhance Diversity, Melissa S. Vilgats, Ryan Ott, Stephanie S. Coster

Virginia Journal of Science

This study explored whether habitat management techniques such as forest thinning and burning promoted biodiversity. Fifteen camera trap stations were established at Fort A.P. Hill in Bowling Green, VA across forest stands with low, medium, and high basal area. Camera traps were deployed for a total of 532 trap nights, and trap success and species diversity were calculated using Shannon’s index. At each site, the distance to trafficable roadways and water sources, vegetation composition, and the percent groundcover, canopy cover, and understory were measured. The cameras captured nine species and recorded a total of 398 trap events. Linear regression was …


First Record Of Orsilochides Scurrilis (Stål) (Hemiptera: Heteroptera: Scutelleridae: Pachycorinae) In The United States, With Notes On The Biology And Distribution Of U.S. Species Of Orsilochides Kirkaldy, A. W. Meeds, Joseph E. Eger Jr., S. D. Carnahan Sep 2021

First Record Of Orsilochides Scurrilis (Stål) (Hemiptera: Heteroptera: Scutelleridae: Pachycorinae) In The United States, With Notes On The Biology And Distribution Of U.S. Species Of Orsilochides Kirkaldy, A. W. Meeds, Joseph E. Eger Jr., S. D. Carnahan

Insecta Mundi

Orsilochides scurrilis (Stål) (Hemiptera: Heteroptera: Scutelleridae) is reported from the United States for the first time based on a specimen collected in Santa Cruz County, Arizona. A key to separate the U.S. species of Orsilochides Kirkaldy is provided. In addition, host plant records and distribution of the other two species of Orsilochides that occur in the U.S., Orsilochides guttata (Herrich-Schäffer) and Orsilochides stictica (Dallas), are analyzed through a combination of digital photo records and museum specimens.


Effects Of Shoreline And Watershed Development On Eastern Lake Michigan Drowned River Mouth Ecology, Megan M. Mader, Carl R. Ruetz Iii Aug 2021

Effects Of Shoreline And Watershed Development On Eastern Lake Michigan Drowned River Mouth Ecology, Megan M. Mader, Carl R. Ruetz Iii

Masters Theses

Lake Michigan’s drowned river mouths (DRM) are hydrologically unique systems with riverine and large-lake influences that create biologically diverse ecosystems. Serving as focal points for human development due to the ecosystem services they provide, DRMs have experienced a history of industrialization, urbanization, and are now moving towards an era of rehabilitation. Today, DRM shorelines have been hardened, their riparian zones have been severely altered, and their watersheds exist on a latitudinal gradient of less to greater anthropogenic stress (agriculture and development). The main goal of this study was to understand the current ecological state of DRMs related to anthropogenic development …


Analyzing Genetic Variation Of The Tussock Cottongrass Among Ecotypes Along A Latitudinal Gradient Through Transcriptomics, Carmen Webster Aug 2021

Analyzing Genetic Variation Of The Tussock Cottongrass Among Ecotypes Along A Latitudinal Gradient Through Transcriptomics, Carmen Webster

Open Access Theses & Dissertations

The Arctic is seeing some of the most extreme effects of climate change that induce environmental pressures, including warmer temperatures and longer growing seasons. Due to this, taxa may need to adapt or migrate in order to survive. The long-lived tussock cottongrass, Eriophorum vaginatum, is a foundation species in the Arctic, and little is currently known about the genetic constraints that could be playing a role in how this species will respond to the changing climate. Specific gene families that play an important role in signaling genetic pathways related to plant phenology and response to environmental stress are likely to …


Climate-Driven Impacts Of Warming And Grazing On Sub-Arctic Coastal Wetlands In Alaska, Ryan T. Choi Aug 2021

Climate-Driven Impacts Of Warming And Grazing On Sub-Arctic Coastal Wetlands In Alaska, Ryan T. Choi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Climate change is rapidly warming the Arctic, especially at lower latitudes. Warmer temperatures and earlier springs are altering the timing of plants and animals, especially for long-distance migratory herbivores. Changes in the timing of both plants and herbivores have the potential to impact plant productivity and nutrient cycling, while also altering plant community diversity and composition.

In chapter 2, I conducted a field experiment to investigate how earlier growing seasons and differences in arrival times of migratory geese influence physical traits of sedge forage species. I found that both an earlier growing season and late grazing by geese had similar …


Exploring Linkages Between Landscape Patterns And Freshwater And Estuarine Bivalves In The Coast Range Of Oregon, Kaegan Michael Scully-Engelmeyer Jul 2021

Exploring Linkages Between Landscape Patterns And Freshwater And Estuarine Bivalves In The Coast Range Of Oregon, Kaegan Michael Scully-Engelmeyer

Dissertations and Theses

Spatial configurations of landscape variables (biotic, abiotic, and socio-ecological) affect and are affected by ecological processes and species in watersheds. This dissertation explores relationships among landscape patterns, ecosystem processes and bivalve species dynamics in coastal watersheds in Oregon, USA. I approached this broad topic through two primary avenues of research: investigating cross-ecosystem threats from pesticide use in forestland management to downstream aquatic environments, and the landscape ecology of an at-risk freshwater mussel species.

Terrestrial land use activities present cross-ecosystem threats to riverine and marine species and processes. Specifically, pesticide runoff can disrupt hormonal, reproductive, and developmental processes in aquatic organisms, …