Life Sciences Commons^™

Fire Severity Mediates Marten And Fisher Occurrence: Impacts Of The Dixie Fire On A Carnivore Community, Christopher James Collier

Cal Poly Humboldt theses and projects

The consumption of an astounding one million acres resulted from California’s largest single fire to date, the 2021 Dixie Fire. The social and economic losses associated with the fire were immediately apparent, but the effects on wildlife remained unknown. While previous research has suggested mixed or low severity fire may be beneficial to certain wildlife species, the responses to megafires are poorly understood for many carnivores. To better understand these responses to severe fire, I used a random sampling design stratified by burn severity to survey in and around the Dixie Fire footprint using baited camera stations. This allowed me …

The Paleoecology Of High-Elevation Bison In The Greater Yellowstone Ecosystem And Implications For Modern Bison Conservation, Darian Bouvier

Electronic Theses and Dissertations

The national mammal of the United States, the American Bison (Bison bison) was once nearly extinct. Populations have recovered to the degree that thousands roam the Great Plains today. Due to their large numbers and body size, this species has an oversized impact on the ecological communities where it lives and is considered a keystone herbivore in modern North American grasslands. This study explores the detailed, seasonally resolved, paleoecology of seven bison from the Greater Yellowstone Ecosystem during the Late Holocene through stable isotope analyses and species niche modeling. Isotopic analyses of δ¹³C, δ¹⁵N, …

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura

Electronic Theses and Dissertations

The tallgrass prairie of North America has changed drastically since colonial settlement, with up to 99% of this region converted for agriculture and other land-uses. Concurrent with grassland conversion, grassland birds have experienced the most extreme, consistent, and widespread population declines of any avian guild. Agricultural lands in the U.S. Midwest were able to provide adequate habitat for several bird species until the 1950’s; however, altered and intensified management practices have degraded much of remaining suitable habitat and undermined ecosystem functions. Consequently, many grassland birds have been identified as Species of Greatest Conservation Need (SGCN) in many State Wildlife Action …

Joint Management Of Upland & Aquatic Habitat For The California Red-Legged Frog & California Tiger Salamander, Kyle E. Verblaauw

Master's Projects and Capstones

As federally and state protected amphibians, the California tiger salamander (Ambystoma californiense) and the California red-legged frog (Rana draytonii) are recipients of ample management focus. Both species face a variety of threats, including habitat loss and alteration, introduction of non-native species, spread of disease, and effects of climate change. While management plans for the California tiger salamander and California red-legged frog exist, they frequently do not consider both species in tandem and often contain multiple shortcomings. This document aims to address the shortfalls of current management by providing practical recommendations for jointly managing the upland and …

Spatial And Temporal Variation Of Nutrients In The Great Lakes-St. Lawrence Basin: Implications For Primary Production In Stream Ecosystems, Nolan Pearce

Electronic Thesis and Dissertation Repository

Growing human populations and associated land use activities has increased the amount of nutrients delivered to surface waters. Eutrophication from the over-enrichment of nitrogen and phosphorus has degraded ecosystem conditions in streams, lakes, and coastal areas worldwide. Thus, the management of anthropogenic nutrient loading is a global concern. This thesis employed a combination of field and experimental research to provide watershed managers with information on the spatial and temporal patterns in stream nutrient enrichment, and the associated ecological effects of anthropogenic nutrient loading in the Great Lakes-St. Lawrence basin. Four studies were completed to address this research goal. First, I …

Examining The Northern Shrimp Fishery In A Changing Gulf Of Maine, Ashley N. Charleson

Electronic Theses and Dissertations

Northern Shrimp (Pandalus borealis) once supported a key commercial fishery in the State of Maine. Since its closure in 2013, the stock has remained in a particularly vulnerable state following recruitment failure, overfishing, and rising water temperatures. Furthermore, without this source of supplemental income, local fishermen have also experienced financial stress following unstable fishing conditions in other fisheries. The collective goal of this research project was to assess factors impacting the feasibility of reopening and maintaining this vulnerable winter fishery. These goals are addressed over 4 chapters. Chapter two offers insight regarding what is most often omitted from the regulatory …

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …

A Review Of The Global Commercial Cephalopod Fishery, With A Focus On Apparent Expansion, Changing Environments, And Management, Corey Clark

HCNSO Student Capstones

Cephalopods are both important predators and prey in many marine environments and important fishery resources in many countries. The global fishery has expanded almost continuously from landings of 580,000 metric tonnes in 1950 to over 4 m.t. in 2007. Cephalopods are ecological opportunists with highly plastic biological characteristics and varied population dynamics. Nearly all commercially harvested species are short-lived and can reproduce quickly, enabling them to evolve more rapidly under high selection pressure relative to many fish competitors and predators. As a result, they may have the biological means to be successful under conditions of long-term global climate change. This …

Effects Of Northern Bobwhite Management On Raccoon Abundance, Habitat Selection, And Home Range In Southwest Missouri, Jacob Cody Mcclain

Graduate Theses and Dissertations

Habitat management has become vital for northern bobwhite (Colinus virginianus) conservation. In Missouri, efforts to conserve remaining populations on public lands have included the use of two management models. The Intensive Management Model (IMM) promotes hard edges, by creating a juxtaposition of different habitat types, while the Extensive Management Model (EMM) maintains a grassland-dominated landscape through the processes of fire and grazing. Preliminary results suggest that bobwhite success is significantly higher on EMM sites than IMM sites. Management efforts through IMM may be hindered by unintentionally managing for nest predators like raccoons (Procyon lotor). Nest predators may forage more often …

Reconciling The Challenge Of Aphanic Species Within Marine Conservation, Kerri L. Bolow

HCNSO Student Capstones

Aphanic species are those within a taxonomic complex that may not be readily distinguishable from other sympatric species. The existence of these species is becoming apparent at an increasing rate through the use of technological tools like molecular genetic analyses. A lack of clarity on the definitions of terms used to describe similar species, how these species are identified, and how prevalent they are can confound identification, description, and management of these organisms. This review collects and defines the terms used to describe these hidden species and suggests the use of the term aphanic for situations where additional information (and …

Aligning Conservation Goals And Management Objectives For Bonneville Cutthroat Trout (Oncorhynchus Clarki Utah) In The Logan River, Utah, Harrison E. Mohn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rivers are often managed without informed knowledge of how sportfish use different areas of the river to reproduce, and rarely take into account the relationship between fish movement and how they are distributed within the river when making management decisions. The population of native Bonneville cutthroat trout (Oncorhynchus clarki utah) within the Logan River is the largest documented population remaining for this imperiled species, and still maintains extremely high numbers of fish in the upper river. Currently, fishing is not allowed in the upper 20 kilometers of the Logan River watershed during spawning, based on the assumption that …

Financial Investment Management For Forest Sustainability, Zarina Ismailova

Electronic Theses and Dissertations

This is paper is discussion about main problems of forest management, whether financial investment has a substantial impact on the long term perspective of forest landscape restoration and, more specifically, what strategy and what financial options are available to make the forest projects more sustainable. A few relevant questions to ask are: who are the main actors in the implementation of FLR projects; which steps have to be taken; and, which financial options would more suitable and would be feasible to implement. There are three main parts of this research to be investigated:

1. forest issues along with their respective solutions, …

Vermont Agricultural Resilience In A Changing Climate: An Investigation Of Farmer Perceptions Of Climate Change, Risk, And Adaptation, Rachel E. Schattman

Graduate College Dissertations and Theses

Climate change forecasts tell of significant challenges ahead for agrifood systems at all scales, from global to highly local. Farmers are often at the forefront of these challenges. How farmers perceive climate related risks, and the actions they take to protect or adapt their lives and livelihoods are therefore a critical area of inquiry. The purpose of this dissertation is to describe how farmers in Vermont, in the Northeastern U.S., think about climate change, and how their experiences and perceptions influence engagement with adaptation or mitigation activities. To this end, my research questions included: (1) what are farmers already doing …

Management Recommendations For Restoration Of The Degraded Olympia Oyster, Ostrea Lurida Carpenter 1864 In Tomales Bay, Ca, Carolyn M. Gibson

Master's Projects and Capstones

This research addresses the effective restoration of Olympia oyster populations in Tomales Bay, Marin County, California. Chapter 2 provides background information on the Tomales Bay estuary, regional history, and ecology of the Olympia oyster. Following this background discussion, each of the three aforementioned degraders of Olympia oyster populations in Tomales Bay is presented: ocean acidification (Chapter 3), sedimentation (Chapter 4), and invasive species (Chapter 5). Each of these issues creates numerous barriers that require the attention of resource protection managers. Chapter 6 presents overall Research Conclusions and Chapter 7 identifies management recommendations to effectively begin the restoration of the Olympia …

Seasonal Warm-Water Refuge And Sanctuary Usage By The Florida Manatee (Trichechus Manatus Latirostris) In Kings Bay, Citrus County, Florida, Danielle C. Sattelberger

HCNSO Student Theses and Dissertations

The largest Florida manatee (Trichechus manatus latirostris) aggregation at a natural warm-water refuge occurs in Kings Bay, Crystal River, FL. Over the last 32 years, the U.S. Fish and Wildlife Service and the State of Florida have created a network of manatee protection areas within Kings Bay including a year-round refuge designation and seven Federal manatee sanctuaries during the winter manatee season (November 15 – March 31). Aerial survey data collected between 1983 and 2012 was used to examine the seasonal change in manatee distribution within Kings Bay in order to assess the effectiveness of current sanctuary sizes …

A Comparison Of Management Strategies For The Federally Endangered Running Buffalo Clover (Trifolium Stoloniferum) On The Blue Grass Army Depot, Ky, Alexi David Dart-Padover

Online Theses and Dissertations

Running buffalo clover (Trifolium stoloniferum) is a federally endangered plant that appears to depend on habitat disturbance, although proposed management strategies such as cattle grazing, mowing, and herbicide application have never been compared in a controlled study. We evaluate the efficacy of these techniques on the Blue Grass Army Depot (BGAD) in Madison County, KY, where one of T. stoloniferum’s largest populations occurs. Fifty-nine patches of T. stoloniferum on the BGAD were treated annually between 2012 and 2014 with combinations of mowing and grass-specific herbicide. Patches of T. stoloniferum also were exposed to one of three types of cattle exposure …

The Supply Chain Of Fair Trade Coffee: Challenges, Opportunities & The Future Inside A Troubled Industry, Katharine D. Lukas

Graduate College Dissertations and Theses

What started as a grassroots effort to aid tradespeople in developing nations, Fair Trade and similar certification models have, over the last sixty years, successfully established themselves as a viable alternative to conventional international trade; the ongoing growth of their market share and volume emphasize the increasing market demand for these alternatives. For coffee, Fair Trade's oldest and most established commodity, over two billion pounds was sold as certified in 2012 alone and the percentage of certified coffee continues to grow in share each year (Volcafe, 2012, Fair Trade USA 2012). As Fair Trade continues to grow, so does the …

Global Population Structure Of The Dusky Shark And Geographic Sourcing Of Shark Fins From Commercial Markets, Teagen K. Gray

HCNSO Student Theses and Dissertations

The dusky shark, Carcharinus obscurus, is a globally distributed, coastal-pelagic species subject to an apparent high level of exploitation. The International Union for the Conservation of Nature (IUCN) lists this species as “Vulnerable” globally, and “Endangered” within western North Atlantic and Gulf of Mexico waters due to an over 80% decline in this region, with no evidence of population recovery. The extensive exploitation of dusky sharks may partly be attributed to the high market value of its fins, but the contribution of individual dusky shark stocks to the fin markets is unknown. This knowledge would be helpful to detect …

Factors Influencing Nest Site Selection By Wood Turtles (Glyptemys Insculpta) In An Altered Forest Landscape, Ellery Ruther

Theses & Honors Papers

There have been many studies concerning wood turtle (Glyptemys insculpta) nest site selection, including studies that evaluate nest site conditions when stream sand banks are not available. However, because of the unique landscape at our study site (high gradient, first order streams) and rapidly diminishing wood turtle populations in Virginia, I am evaluating wood turtle nest site selection. Nine physiographic and vegetative characteristics from nest, positive, negative-one and negative-two control locations were evaluated using binomial generalized linear models and then best fit models were chosen using Akaike's Information Criterion (AIC). It was found that in lieu of typical stream …

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …

Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two experiments were conducted in the semi-arid (400 millimeter annual rainfall) Macquarie region of New South Wales, Australia, at the Trangie Agricultural Research Station (31° 59'S; 147° S7'E), to examine (a) the way botanical parameters can be used to separate grazing and climatic impacts on range vegetation, and (b) how this delineation affects application of range science tenets (site, condition and trend) to different pasture types.

Two range sites were studied: Site 1, a light soil type, was dominated by annual grasses, legumes and forbs, whereas perennial grasses (mainly Chloris acieularis and Chloris truncata) dominated the heavy soils of …