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2016

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Full-Text Articles in Life Sciences

Effects Of Hydrology On The Growth And Recruitment Of Stream Fish In The Eastern Broadleaf Province Of Minnesota, Eric J. Krumm Jan 2016

Effects Of Hydrology On The Growth And Recruitment Of Stream Fish In The Eastern Broadleaf Province Of Minnesota, Eric J. Krumm

All Graduate Theses, Dissertations, and Other Capstone Projects

Agricultural practices and urban development have altered streamflows within the Eastern Broadleaf Province of Minnesota. Stream-flow alteration can produce significant changes in native freshwater communities. Therefore, knowledge of streamflow effects on representative freshwater populations and communities within the province are needed to maintain ecological integrity. Fish community and population dynamics often display predictable responses to flow regimes, which can make fishes model organisms for examining flow-ecology relationships.

In lotic systems, annual variation in streamflow can influence the annual growth and recruitment of fishes. Understanding the growth and recruitment of fish populations is essential for management and conservation efforts. Growth can …


Development And Evaluation Of A Habitat Suitability Model For White-Tailed Deer In An Agricultural Landscape, Eric Anstedt Jan 2016

Development And Evaluation Of A Habitat Suitability Model For White-Tailed Deer In An Agricultural Landscape, Eric Anstedt

All Graduate Theses, Dissertations, and Other Capstone Projects

White-tailed deer (Odocoileus virginianus) are an ecological, economical, and socially significant species that occupy a variety of ecoregions. White-tailed deer are mobile habitat generalists that prefer habitats containing woody cover. Deer have successfully adapted to habitat-fragmented, agricultural landscapes. As a result, deer are not uniformly distributed across intensively cultivated areas, which make field surveys difficult with often highly variable spatial data. To increase sampling efficiency (deer observed / sampling effort), the landscape can be stratified based upon preferred habitat types. Habitat suitability models (HSI) have been used to represent hypothesized wildlife-habitat relationships, and therefore the likelihood of deer being observed …


Ecology Of Largemouth Bass In An Aging Reservoir: Implications For Creating A Trophy Largemouth Bass Fishery, Jason Breeggemann Jan 2016

Ecology Of Largemouth Bass In An Aging Reservoir: Implications For Creating A Trophy Largemouth Bass Fishery, Jason Breeggemann

Electronic Theses and Dissertations

There are an estimated 3-9 million small reservoirs and nearly 1,000 large reservoirs in the United States. Most of these reservoirs were built several decades ago and are experiencing symptoms of reservoir aging, including loss of habitat, sedimentation, and decreased fishery production. Furthermore, over the last several decades, there has been an increasing interest among anglers for high quality, trophy fisheries. However, little is known about exactly how the reservoir aging process affects the ecology and especially growth potential of Largemouth Bass, particularly under potential climate change scenarios. Grand Lake in TX is a 45ha ageing reservoir that was built …


Assessing The Use Of Food Waste Biochar As A Biodynamic Plant Fertilizer, Rachel Mazac Jan 2016

Assessing The Use Of Food Waste Biochar As A Biodynamic Plant Fertilizer, Rachel Mazac

Departmental Honors Projects

Biochar is a charcoal-like substance produced from plant material such as food waste. Converting food waste into a useful product would mitigate environmental damage through reduced landfill inputs, reduced greenhouse gas production, and increased benefits to soils. I asked (1) if biochar improved plant growth and (2) if the effects of biochar varied among different samples of mixed food waste (batches) and between different biochar preparation times (treatments). Four independent batches of biochar were prepared with assorted, uncooked food waste collected from a university dining facility. Each batch was dried then placed in a covered ceramic pot at 260℃ for …


The Impact Of Endocrine-Disrupting Chemicals On Wildlife Conservation, Eda Reed Jan 2016

The Impact Of Endocrine-Disrupting Chemicals On Wildlife Conservation, Eda Reed

Honors Theses

Endocrine-disrupting chemicals (EDCs), such as those from plastics and pesticides, have been hypothesized to affect wildlife populations. According to the U.S. National Institute of Environmental Health Sciences, EDCs ‘are chemicals that may interfere with the body’s endocrine system and produce adverse developmental, reproductive, neurological, and immune effects in both humans and wildlife.’ A growing number of studies suggest wildlife are being exposed to EDCs, but how EDCs affect wildlife health and wildlife conservation is less well-understood. Through scientific literature analysis and a survey of wildlife conservationists and practitioners, this study aims to determine the current state of knowledge and data …


The Changes In Woodlot Land Cover From 1988 To 2006 Within Private/Farmland In Hancock County, Ohio, Louis C. Birchall Jan 2016

The Changes In Woodlot Land Cover From 1988 To 2006 Within Private/Farmland In Hancock County, Ohio, Louis C. Birchall

Williams Honors College, Honors Research Projects

The amount of woodlots in Ohio have dramatically decreased since the introduction of settlers into the State. The removal of forest for open space, urban areas, fuel and resources was key to this change. Since the development of the economy to a more service based industry in recent years, woodlots have begun to return in certain areas. This research shows the change in woodlot patterns in Hancock County, Ohio from 1988 to 2006.

The analysis was done by classifying the data into 'woodlot' and 'other land use' by using image segmentation and manual editing processes. Accuracy checks were conducted on …


Identification And Quantification Of Zooplankton In Ne Ohio Drinking Water Reservoirs, Michael Vigorito Jan 2016

Identification And Quantification Of Zooplankton In Ne Ohio Drinking Water Reservoirs, Michael Vigorito

Williams Honors College, Honors Research Projects

Cyanobacteria, or blue-green algae, are present in most freshwater ecosystems and are usually harmless. When these algae swell in numbers, they release harmful toxins that can be detrimental to animal and human health, and can destroy ecosystems. For this reason, many scientists and engineers have studied these harmful algal blooms in an attempt to predict, prevent, or control them to keep people and ecosystems safe. One of the variables in this investigation is the presence and quantity of zooplankton. These animals could play an important role in the prevalence of cyanobacteria, but more information is needed to determine what that …


Invasive Plant Ecology In Vermont: Insights From Spatial Analysis And Interactions Of Garlic Mustard (Alliaria Petiolata) With Native Plants And Invertebrates, Chenin Kathleen Limback Jan 2016

Invasive Plant Ecology In Vermont: Insights From Spatial Analysis And Interactions Of Garlic Mustard (Alliaria Petiolata) With Native Plants And Invertebrates, Chenin Kathleen Limback

Graduate College Dissertations and Theses

Causes and patterns of invasive plant species establishment and success depend broadly upon their ecology, including habitat suitability and interactions with other plants and animals. Here I examine the traits and distribution of invasive plants in Vermont, using spatial analysis, laboratory and field studies. I used GIS to investigate environmental factors correlated with presence of 19 invasive plant species in Vermont campgrounds. My results support the assumption that human dispersal of invasive plant seed and stock may be more important than natural dispersal of these plant species to new sites. I also investigate in-depth the relationships of invasive herbaceous garlic …


Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta Jan 2016

Raptors In Temperate Grasslands: Ecology Of Ferruginous Hawk, Golden Eagle, And Northern Harrier In The Northern Great Plains, Shubham Datta

Electronic Theses and Dissertations

Ferruginous hawks (Buteo regalis) are a grassland and shrubland obligate nesting raptor and prefer lightly grazed pasture or idle areas for nesting. Their population reportedly declines in number if more than 30% of an area is cultivated and they rarely nest in areas dominated by croplands. Golden eagles (Aquila chrysaetos) are long-lived raptors with high nest-site fidelity and relatively low reproductive success. Population trends of golden eagles in western United States are unclear although long-term monitoring of populations shows declines in occupancy and breeding performance. Northern harriers (Circus cyaneus) prefer relatively open grasslands and …


Impacts Of Forest Disturbance On Small Mammal Distribution, Allyson Lenora Degrassi Jan 2016

Impacts Of Forest Disturbance On Small Mammal Distribution, Allyson Lenora Degrassi

Graduate College Dissertations and Theses

Natural habitat in the eastern United States has diminished over the past century because of the effects of invasive species. Both plant and animal invaders can alter habitat structure and may decrease survival of native species. The degree to which an invasive species alters ecosystem function depends on the functional characteristics of affected species and the resulting cascading effects. The loss of important native species, such as foundation species, can potentially influence the structure and distribution of animal communities because of the foundation species' unique ecosystem roles. The foundation species concept is relatively new to the terrestrial ecology and the …


Gene Flow And Genetic Structure Of The Seagrass Thalassia Hemprichii In The Indo-Australian Archipelago, Udhi Eko Hernawan Jan 2016

Gene Flow And Genetic Structure Of The Seagrass Thalassia Hemprichii In The Indo-Australian Archipelago, Udhi Eko Hernawan

Theses: Doctorates and Masters

How genetic variation is distributed across space (genetic structure) and what factors influence the spatial genetic structuring is one of the primary questions in population genetics. The interaction between species biology (e.g. life-history traits) and physical processes operating in the seascape over time, including palaeo-historical events (e.g. sea level fluctuations) and contemporary processes (e.g. ocean currents), have been predicted to influence the extent of gene flow and the spatial genetic structuring in marine organisms. However, the relative contribution of each factor in governing the genetic pattern remains unclear. This study examined the pattern of genetic structure and the factors influencing …


To Jump Or Not To Jump: Mule Deer (Odocoileus Hemionus) And White-Tailed Deer (Odocoileus Virginianus) Crossing Decisions, Emily N. Burkholder Jan 2016

To Jump Or Not To Jump: Mule Deer (Odocoileus Hemionus) And White-Tailed Deer (Odocoileus Virginianus) Crossing Decisions, Emily N. Burkholder

Undergraduate Theses, Professional Papers, and Capstone Artifacts

There have been recent efforts to enhance ungulate movement through modified fencing structures. Ungulates such as mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus) typically negotiate fences by either jumping over fencing or going under. Here we examine crossing success and crossing decisions of mule deer and white-tailed deer and determine factors that influence crossing success and the impending decision to jump over or crawl underneath fencing. Using a BACI (Before-After-Control-Impact) design, we deployed remote cameras along fence lines in three study areas; Canadian Forces Base (CFB) Suffield and OneFour research center in Southeastern Alberta, …


Influence Of Structural Complexity And Location On The Habitat Value Of Restored Oyster Reefs, Melissa Ann Karp Jan 2016

Influence Of Structural Complexity And Location On The Habitat Value Of Restored Oyster Reefs, Melissa Ann Karp

Dissertations, Theses, and Masters Projects

In the Chesapeake Bay, < 1% of the historic oyster population remains, and efforts have been increasing to restore oysters and the services they provide. Building reefs that successfully provide ecosystem services–especially habitat and foraging grounds–may require different restoration techniques than those previously used, and success may depend on reef morphology (complexity), location, and environmental conditions. Salinity and habitat complexity are two important factors that may interact to effect benthic communities and predator-prey interactions on restored reefs. The goals of this project were: (1) Characterize the benthic communities on restored oyster reefs in lower Chesapeake Bay, and (2) examine the effects of structural complexity and salinity on benthic communities and predator-prey interactions. A two-year field survey of restored reefs was carried out in four rivers in lower Chesapeake Bay to characterize faunal communities on restored reefs and to quantify the effect of reef complexity on faunal communities. A laboratory mesocosm experiment was conducted to examine the effect of reef complexity on predator foraging. In total, 61 macrofaunal species were identified among all samples, and restored reefs supported on average, 6,169 org/m2 and 67.88 g-AFDW/m2. There were significant differences in the community composition and diversity among the rivers, and salinity was the environmental factor that best explained the observed differences in species composition across the rivers. Salinity and rugosity (i.e., structural complexity) both positively affected diversity, while salinity negatively affected macrofaunal abundance and biomass. Oyster density and rugosity positively affected macrofaunal biomass, and oyster density positively affected mud crab, polychaete, and mussel densities. In the mesocosm experiment, predator foraging, measured by proportion and number of prey consumed, was significantly reduced in the presence of oyster shell structure. However, predators were able to consume more prey when prey density was increased, even in the presence of oyster shell structure. These results combine to enhance our understanding of the benefits of increased habitat complexity for both prey and predators on restored oyster reefs. Increasing complexity worked to increase the abundance, biomass, and diversity of organisms inhabiting restored reefs, and even though predator consumption was reduced in the presence of structure compared to non-structured habitat, predators were able to consume more prey individuals when prey density was increased. Therefore, increasing the structure of oyster reef habitat may benefit prey species by providing refuge habitat, and benefit predators by providing an increased abundance of available prey items.


The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje Jan 2016

The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje

Dissertations, Theses, and Masters Projects

Thousands of floating objects, known as drifting fish aggregating devices (dFADs), are released every year by commercial tropical tuna purse seine vessels in the three equatorial oceans to aggregate tuna and increase catch. The escalation in the number of dFADs deployed over the last three decades has caused changes in fishing effort that are poorly reflected in traditional indices of purse seine effort and catch per unit of effort (CPUE). In addition, concerns have been raised regarding the impacts of such high numbers of dFADs being deployed on both catch and bycatch species. I studied two aspects of dFAD deployments …


Seasonal Habitat Selection Of The North American Porcupine (Erethizon Dorsatum) In A Coastal Dune Forest, Cara L. Appel Jan 2016

Seasonal Habitat Selection Of The North American Porcupine (Erethizon Dorsatum) In A Coastal Dune Forest, Cara L. Appel

Cal Poly Humboldt theses and projects

Wildlife-habitat relationship studies are important for understanding the factors that determine where species occur in space and time. Habitat selection by generalist species should be studied on fine spatial and temporal scales to avoid masking important differences between seasons, localities, or orders of selection. I conducted the first study of habitat use and general ecology of North American porcupines (Erethizon dorsatum) in a coastal dune environment. Specifically, I assessed changes in body mass, home range size, and habitat selection in relation to the potential for seasonal nutritional and survival bottlenecks as reported elsewhere. Although they are considered generalists, …


White-Rot Fungi As Pretreatment Agents For Wood Destined For Biofuel Applications, Ryan M. Kalinoski Jan 2016

White-Rot Fungi As Pretreatment Agents For Wood Destined For Biofuel Applications, Ryan M. Kalinoski

Masters Theses

Efficient and economical conversion of lignocellulosic biomass to biofuels is often hampered by the chemical recalcitrance of the material. Inexpensive and environmentally-friendly pretreatment processes are therefore desirable in order to lower the cost of biofuel production and minimize negative environmental impacts. To that end, we have explored the use of a naturally occurring white-rot fungus, Trametes versicolor, as a direct pretreatment agent for hardwood destined for biofuel applications. Specifically, we examined the pretreatment effects on the hardwood mixture after treatment with the wild-type strain of T. versicolor (52J) compared with those from a cellobiose dehydrogenase (CDH)-deficient strain (m4D) , …