Ecology and Evolutionary Biology Commons^™

Wire Netting Reduces African Elephant (Loxodonta Africana) Impact To Selected Large Trees In South Africa, Kelly Derham

Masters Theses & Specialist Projects

African elephants (Loxodonta africana) are ecosystem engineers in that they substantially alter the environment through their unique foraging and feeding habits. At high densities, elephants potentially have negative impacts on the environment, specifically to large trees. Because of this, recent increases of elephants in the Associated Private Nature Reserves (APNR) on the Western Boundary of Kruger National Park, South Africa have caused concern regarding the health of several species of tree. My objective was to assess the effectiveness of wrapping protective wire netting around the trunk of the tree in preventing and reducing bark stripping by elephants. 2,668 …

Elements Of A Successful Plan: Marine Invasive Species Management, Caitlin Gerber

Muskie School Capstones and Dissertations

Marine invasive species are becoming an increasing threat to marine ecosystems and coastal economies around the world. The purpose of this study is to determine the elements of an effective invasive species program in a variety of places and to come up with suggestions for how to implement this in Maine, specifically in terms of combatting Green Crabs

Trophic Status, Energetic Demands, And Factors Affecting Lahontan Cutthroat Trout Distribution In Pyramid Lake, Nevada, Nicholas A. Heredia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The progression of human development across the landscape has caused declines to both terrestrial and aquatic fauna. Many fishes, specifically native salmonids, have seen reductions in both population size and geographic distribution resulting from reduced habitat, overharvest, and the introduction of non-native predators and competitors. A native North American fish particularly hard hit by these types of actions, Lahontan cutthroat trout, are now limited to less than 10% of their historical habitat, and currently occupy only half of the lakes that they once occupied.

In Pyramid Lake, Nevada, where Lahontan cutthroat trout were once locally extinct, due to overfishing, water …

Ringtail Distribution, Dermatoglyphics, And Diet In Zion National Park, Utah, Adrian Argie Roadman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current scientific knowledge of the ringtail (Bassariscus astutus) is limited, thus impeding appropriate management decisions. Ringtails in Zion National Park, Utah, are rarely seen, but are involved in increasing occurrences of negative interactions with park visitors and employees such as food theft and denning in buildings, interactions which are harmful to both parties. To manage this conflict, an update to the general knowledge about the status of the population is required as the only previous study on ringtails in this area was conducted in the 1960s. Using noninvasive techniques provides dependable large-scale population information. I used two noninvasive detection methods …

Habitat Characteristics Of Mexican Spotted Owls (Strix Occidentalis Lucida) In The Canyonlands Of Southern Utah, Leah R. Lewis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mexican Spotted Owls are considered a threatened species by the US Fish and Wildlife Service. Therefore, they must be properly managed and protected by federal and state agencies. In this study I explored the habitat characteristics used by Mexican Spotted Owls in the canyonlands region of southern Utah. I spent three summer field seasons (May-September) from 2010 – 2013 locating Mexican Spotted Owl sites and measuring vegetative and geologic features at these sites. I found that canyon width and very tall vegetation influenced Mexican Spotted Owl presence, suggesting that these owls prefer narrow canyons that are vegetated with trees.

Based …

The Ecosystem Role Of Fishes In Lotic Environments, Christopher C. Wheeler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

It is important for humans to understand how ecosystems work because we depend on them for a variety of products and services. For example, rivers and streams provide fisheries, improved water quality, and recreational opportunities to many individuals. In rivers, interactions among fishes, other stream plants and animals, and the physical river environment can influence continued provision of these valuable services. However, the role played by many freshwater fishes in the provision of these services remains unknown. Additionally, it is important to identify different factors that affect the outcome of interactions involving riverine fishes. To address these issues, I evaluated …

Activated Carbon Decreases Invasive Plant Growth By Mediating Plant-Microbe Interactions, Nicole E. Nolan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

To restore lands invaded by dense, non-native vegetation, it may be necessary to develop targeted restoration tools than can remove the mechanism used by these non-native species as a competitive advantage. Activated carbon (AC) is one such tool, with the ability to disrupt the mechanisms of plant to plant communication (allelopathy) and positive plant to microbe communication commonly used by non-native species. Previous studies have shown the success of high concentrations, 1000g/m², of AC in native plant community restoration on a small scale. Here, our goals are twofold: first, to test AC effectiveness in restoring desirable plant communities …

A Male Spider’S Ornamentation Polymorphism Maintained By Opposing Selection With Two Niches, Bo Deng, Alex Estes, Brett Grieb, Douglas Richard, Brittney Hinds, Eileen Hebets

Eileen Hebets Publications

The Levene mechanism to maintain genotypic polymorphism by opposing selection on genotypes in multiple niches was proposed 60 years ago, and yet no systems were found to satisfy the mechanisms rather restrictive conditions. Reported here is such an example that a wolf spider population lives in a habitat of mixed rocks and leafy litter for which the females are phenotypically indistinguishable and the males have two distinct phenotypes subject to opposing selection with respect to the substrates. Census data is best-fitted to a population genetics model of the Levene type. A majority of the best fit support polymorphism, with many …

Tactical Adjustment Of Signaling Leads To Increased Mating Success And Survival, Laura Sullivan-Beckers, Eileen A. Hebets

Eileen Hebets Publications

Most sexually reproducing animals overcome the challenge of searching for and attracting mates by utilizing signals that are broadcast through a spatially and temporally varying environment. A diverse suite of behavioral solutions exist for overcoming such environmental variability, including the adjustment of signaling behavior based upon receiver feedback. Few studies have directly examined the relationship between such tactical signaling adjustments and proxies of male fitness; the few that have, failed to find a relationship. Using the wolf spider, Schizocosa rovneri, we set out to first quantify among-male variation in the form and degree of responsiveness to female feedback. Following …

Movement And Habitat Use Of Bonneville Cutthroat Trout (Oncorhynchus Clarki Utah): A Case Study In The Temple Fork Watershed, Ryan L. Lokteff

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Movement patterns and habitat use of Bonneville cutthroat trout (Oncorhynchus clarki Utah) in tributaries of the Logan River watershed are greatly affected by habitat alterations created by North American Beaver (Castor canadensis). Evaluation of cutthroat trout habitat use in these watersheds is also complicated by biotic interactions with invasive brown trout (Salmo trutta) and brook trout (Salvelinus fontinalis). My objectives in this thesis were to 1.) Evaluate the passage of beaver dams by each trout species in the Temple Fork watershed and 2.) Evaluate the habitat use of cutthroat trout in the presence …

Influence Of Wildfire Disturbance And Post-Fire Seeding On Vegetation And Insects In Sagebrush Habitats, Ashley T. Rohde

Boise State University Theses and Dissertations

Disturbance events alter community composition and structure because of differences in resistance and resilience of individual taxa, changes in habitat resulting in colonization by new taxa and alteration of biotic interaction patterns. Recent changes in disturbance types, frequencies and intensities caused by anthropogenic activities may further alter community composition and structure if these disturbances exceed the tolerances or adaptations of some taxa. In sagebrush steppe habitats of the western United States, wildfire is the current dominant disturbance type, burning millions of hectares annually. Further, up to 90% of sagebrush-steppe ecosystems are affected by anthropogenic influences such as invasive species. Post-fire …

Macroinvertebrate Assemblages And Dynamic Soil Properties: Influence Of Dredging, Bianca N. Ross

Senior Honors Projects

Bianca Peixoto

Senior Honors Project

Macroinvertebrate Assemblages and Dynamic Soil Properties: Influence of Dredging: Abstract

The habitat characterization of subaqueous soils is important for inventorying natural resources and monitoring changes in ecosystem processes. This project aimed to characterize benthic communities within coastal ponds of southern Rhode Island, and develop an understanding of how these communities change due to habitat alterations. I explored the distribution of benthic biology among a range of estuarine subaqueous soils and the effect of anthropogenic disturbance (dredging) on these distributions. The term “benthic” refers to the collection of organisms living in the substrate at the interface …

The Development And Application Of Nebraska’S Northeast Habitat Management Decision Support System, Christopher Jorgensen, Roger Grosse, Marian Langan, Alicia Hardin, Eric Zach, Karie Decker, Andrew Bishop

Nebraska Game and Parks Commission: Staff Research Publications

In the face of the compounded effects of a changing climate, exponential human population growth, and accelerated land-use change, implementation of effective conservation measures grows ever more challenging, as conservation organizations are often faced with limited funding and resources. Given the complexity of managing for multiple species, each inhabiting various local habitat types, it is astonishing that we can pinpoint specific areas and tracts of land within the focus area where conservation measures would benefit all species (Figure 3). Here we demonstrate the usefulness of decision support systems in aiding policymakers and habitat managers in making decisions about where to …

Phenological Relationships Of Nesting Barn Swallows In A Swallow-Fly-Cattle System And Their Potential Role In Suppression Of Pest Flies In A Warming Climate, Claire Stuyck

All Theses

Conservation efforts for birds that provide ecosystem services in agricultural systems require management approaches that cross disciplines. This information is communicated through a variety of outlets but rarely in ways that interface effectively with normal management approaches. The disconnect between agriculture and wildlife conservation reduces the likelihood that ecosystem service benefits will be realized. One understudied ecosystem service provided by birds such as barn swallows (Hirundo rustica) is their role in suppression of flies that are pests to livestock. Climate change, however, may differentially affect flies that respond largely to temperature, and swallows that migrate and respond to photoperiod and …

Assessing The Response Of Small Mammal Functional Guilds To A Simulated Pathogen Attack In A Deciduous Forest Ecosystem, Katie Keck

All Theses

Oak trees (Quercus species) are a foundation species that influence the population dynamics of other organisms by stabilizing ecosystem processes. Globally, oak-dominated forests have experienced widespread mortality due to the fungal pathogen, Phytophthora ramorum, which causes the disease Sudden Oak Death (SOD). I investigated the impact of a simulated pathogen attack such as SOD on the small mammal assemblage of an oak forest in Cornwall, New York. Specifically, I tested the hypothesis that specialist species are most impacted by the loss of foundation species and that they would decline in abundance because of changes in food and habitat resources. In …

Persistence Of A Vulnerable Semi-Aquatic Turtle In An Intensively-Managed Forest Landscape, Christopher O'Bryan

All Theses

Understanding spatial and population ecology of organisms allows land managers to predict how changes in distribution and composition of landscape features influence persistence. Our goal was to investigate body size, sex ratios, survival, individual movements, and habitat selection of a vulnerable freshwater turtle species, the spotted turtle (Clemmys guttata), in an intensively-managed forest landscape in eastern North Carolina, USA. Spotted turtles naturally occur in wetland-dominated landscapes, but this system is heavily-altered, with >222,000 hectares of pine plantations and >10,000 km of ditches managed by Weyerhaeuser Company. During 2012-2013, we captured and individually marked 280 turtles, and used radio-telemetry (n = …

Diversity And Ecology Of Host-Seeking Mosquitoes In Irrigated Agro-Ecosystems Of Clay County, Nebraska, Alister K. Bryson

Department of Entomology: Dissertations, Theses, and Student Research

In the United States, Nebraska has the third highest incidence of human West Nile virus (WNV). Since WNV was first detected in the state in 2002, 3,422 confirmed cases and 57 deaths have been reported. Irrigated agro-ecosystems, which have been associated with elevated WNV incidences in other states, are prevalent in Nebraska. The objectives of this investigation were to 1) characterize mosquito abundance and diversity in irrigated agro-ecosystems, and 2) evaluate associations of two primary vectors of WNV, Culex tarsalis and Culex pipiens, with irrigation methods (sprinkler vs. surface) and crop type (corn vs. soybean). Investigations were conducted …

Response Of Large River Fishes To A Prolonged High Water Event In The Missouri River, Nebraska, Nicholas Paul Hogberg

School of Natural Resources: Dissertations, Theses, and Student Research

Regulation and modification of large rivers to accommodate human uses have been a root cause of freshwater biodiversity declines. The Missouri River is among the most drastically-altered large river systems in North America, with a series of mainstem impoundments in the upper watershed altering flow characteristics downstream, and channelization throughout the lower river homogenizing instream habitat and reducing off-channel habitat. Precipitation events during the winter and spring 2010-2011 caused flooding of the greatest magnitude and duration since reservoir completion. The large magnitude and long duration of this flood made it unlike any flood in recent history and provided a unique …

Development Modeling Of Lucilia Sericata And Phormia Regina (Diptera: Calliphoridae), Amanda L. Roe

School of Natural Resources: Dissertations, Theses, and Student Research

The relationship between insect development and temperature has been well established and has a wide range of uses, including using blow flies for postmortem (PMI) interval estimations in death investigations. To use insects in estimating PMI, we must be able to determine the insect age at the time of discovery and backtrack to time of oviposition. Unfortunately, existing development models of forensically important insects are only linear approximations and do not take into account the curvilinear properties experienced at extreme temperatures. A series of experiments were conducted with two species of forensically important blow flies (Lucilia sericata and Phormia …

Accuracy Or Precision: Implications Of Sample Design And Methodology On Abundance Estimation, Lucas K. Kowalewski

School of Natural Resources: Dissertations, Theses, and Student Research

Estimation of population size by spatially replicated counts (point-count method) has been used for many large-scale animal-monitoring programs, yet its application in aquatic environments has been limited. Multiple site-specific estimates of abundance can be averaged and combined with covariate data to predict total abundance across an area of interest. Covariate data also provide an understanding of the relationship between abundance and habitat use, which is a fundamental interest of many animal-population investigations. Design of sampling scenarios for point-count population-estimate surveys can influence the accuracy and precision of the population estimate. The first objective of this study was to examine how …

Population Response To Climate Change: Wintering Strategy Has Carryover Effects On The Timing Of Nest Initiation And Mate Choice In A Partial Migrant, The American Kestrel (Falco Sparverius), Alexandra Marie Anderson

Boise State University Theses and Dissertations

The ability of a population to respond to climate change will depend on phenotypic plasticity, adaptation, or both. Bird populations have already responded to warming temperatures by shifting their distributions, adjusting migration distance and timing, and breeding earlier. A population of American kestrels (Falco sparverius) in southwestern Idaho has advanced its nesting by approximately 30 days, on average, in the last 30 years and this has been correlated with changes in winter climate. The mechanisms allowing for this shift, however, are not clearly understood. I investigated if assortative mating of wintering kestrels and non-wintering kestrels is accompanying to …

Pelargonium (Geraniaceae) And The Long-Tongued Fly Pollination Guild: Coevolution And Polymorphism In A Specialized Pollination System, Emily M. Blank

Honors Scholar Theses

In South Africa, a group of long-tongued flies and the flowering plants they pollinate form a unique and diverse pollination guild system almost entirely endemic to the Greater Cape Floristic Region. This system makes up only a small portion of the biodiversity of the Region, but it is likely a key to understanding the evolutionary processes that have lead to the observed biodiversity. Aside from its unusual pollinators, this guild system is of particular interest due to the extremely labile morphology of both the fly species and the associated flowering plant species, which geographically vary significantly in proboscis lengths and …

Paleozoic Seed Bank And Their Ecological Significance, Petra Seka Yehnjong

Electronic Theses and Dissertations

Soil seed banks are a reservoir of viable seeds present in the soil in plant communities. They have been studied and characterized in various ways in different habitats. However, these studies are limited to modern seed banks. This study extends seed bank studies to the Paleozoic Era. It was hypothesized that size distribution and seed density in Paleozoic seed banks exhibit similar patterns as in modern seed banks. Seed sizes and seed density of fossil seed from Wise Virginia were estimated. Modern seed bank information was obtained from published data. Data were analyzed using one-way ANOVA and Kruskal-Wallis test. The …

Diel Patterns Of Foraging Aggression And Antipredator Behavior In The Trashline Orb-Weaving Spider, Cyclosa Turbinata, James C. Watts

Electronic Theses and Dissertations

Few studies have rigorously assessed the adaptive value of diel rhythms in animals. We laid the groundwork for assessing the adaptive rhythm hypothesis by assaying diel rhythms of foraging and antipredator behavior in the orb-weaving spider Cyclosa turbinata. When confronted with a predator stimulus in experimental arenas, C. turbinata exhibited thanatosis behavior more frequently and for longer durations during the day. However, assays of antipredator response within webs revealed more complex diel patterns of avoidance behaviors and no pattern of avoidance behavior duration. Assays of prey capture behavior found that the likelihood of exhibiting prey capture behavior varied significantly …

Population Genetics And Microbial Communities Of The Gopher Tortoise (Gopherus Polyphemus), Daniel Lyle Gaillard

Dissertations

The gopher tortoise, Gopherus polyphemus, is an endangered species living in the southeastern United States. The recent and drastic decline in tortoise numbers has resulted in a multi-faceted approach to conserve this species. I used a population genetic approach to determine the population structure, genetic diversity and barriers to gene flow at a broad, regional and local scale. Tortoises are divided into five distinct genetic populations at the broad scale, the central populations have the highest levels of genetic diversity and the Tombigbee, Mobile, Apalachicola, Suwannee and St. John’s Rivers appear to be barriers to gene flow. At the regional …

The Delivery, Speciation, And Fate Of Trace Elements In St. Louis Bay, Mississippi, Gopal Bera

Dissertations

Estuaries are dynamic regions in which there can be significant modification of the riverine flux of trace elements to the open ocean due to various geochemical, physical, and biological processes. Additionally, estuaries are often subject to anthropogenic inputs of trace elements. The first portion of this study investigated the source, behavior, and sediment interaction of anthropogenic stable cesium (Cs) in St. Louis Bay (SLB), MS. A consistent increase in stable Cs concentration was noticed in sediment cores starting from a period when a titanium dioxide refinery on SLB started operations. Weak correlation between Cs and clay percentage and strong correlations …

Biogeochemistry Of Trace Elements In The Mixing Zone Of The Mississippi And Atchafalaya Rivers And Chemical Distributions As Affected By The Deepwater Horizon Blowout, Dongjoo Joung

Dissertations

Selected trace elements (TEs), dissolved organic carbon, and nutrients were studied in Louisiana Shelf waters including the Mississippi (MR) and Atchafalaya (AR) River plumes during periods of high, intermediate, and low river discharges. Seasonal variations in TEs were observed at low salinity, reflecting seasonal changes in the river water endmembers. Shelf surface water dissolved Mo, Cs, U, Ni, and Cu showed conservative behavior with minor scattering in some high salinity waters. Based on associated mixing experiments, nutrient and chlorophyll distributions, as well as surface-bottom concentration contrasts, the non-conservative behavior of TEs was variously related to colloidal flocculation (Fe, Cr), biological …

Plasticity In Female Mate Choosiness: A Result Of Variation In Perceived Predation Risk And The Interaction Of Female Age And Male Density, Ashley N. Atwell

School of Biological Sciences: Dissertations, Theses, and Student Research

In many species, female mate choices can be a strong source of sexual selection. Females often prefer a certain male phenotype, and this can be due to benefits females gain from mating with preferred males. However, such benefits can sometimes be outweighed by the cost of searching for a preferred male. These costs and benefits often change concomitantly with changes in environmental (e.g., predator abundance and conspecific density) and internal factors (e.g., female age). Thus, female mate choosiness (the degree to which preferences for certain males are expressed) should often be plastic. Plasticity in female mate choosiness may be complicated …

The Equitable Contributions Of Environment, Management And Restoration Status On Grassland Diversity And Composition, Raeann C. Powers

School of Biological Sciences: Dissertations, Theses, and Student Research

Plant composition is controlled by a combination of environmental, biotic, historical and management factors. Although there has been much focus on restoring grassland diversity, it is unclear which factors and/or interactions of factors are constraining diversity in grasslands and the relative influences of different factors. We measured soil fertility, soil texture, grazing intensity, fire frequency and plant cover in 694 plots, located within 33 remnant and restored fields in managed grasslands in the central Great Plains. Using univariate (general linear model) and multivariate (PERMANOVA) analyses, we identified significant factors and their relative contributions to plant richness, evenness, floristic quality index …

Two New Species Of Euscorpius From Euboea Island, Greece (Scorpiones: Euscorpiidae), Victor Fet, Michael E. Soleglad, Aristeidis Parmakelis, Panayiota Kotsakiozi, Iasmi Stathi

Biological Sciences Faculty Research

We describe two new species of the genus Euscorpius from Euboea Island, Greece: E. birulai sp.n. (Agia Triada Cave) and E. mylonasi sp.n. (Mt. Dirfi). The cave species E. birulai sp.n. is morphologically close to E. koschewnikowi Birula, 1900 from Mt. Athos, Greece. Species-level divergence of E. mylonasi sp.n. is also confirmed by multiple DNA markers. According to DNA data, an undescribed population from the nearby Skyros Island is closely related to E. mylonasi sp.n.