Biology Commons^™

Modeling The Spread Of Sudden Oak Death Across A Heterogeneous Landscape In Redwood National Park Using A Spatially-Explicit Epidemiological Model, Laura A. Morgan

Cal Poly Humboldt theses and projects

The pathogen Phytophthora ramorum, the causal agent of Sudden Oak Death (SOD), is responsible for the deaths of millions of oak (Quercus spp.) and tanoak (Notholithocarpus densiflorus) trees in California and Oregon (USA). A recent infection in Redwood National Park (RNP) in California (USA) provided an opportunity to adapt an existing SOD model to assess the efficacy of current and proposed management strategies. A common method of SOD treatment includes killing both infected and uninfected hosts in the area of infection, as well as the area surrounding the infection to create buffers to account for undetected …

The “Precautionary Principle” – A Work In Progress, Shelley Adamo

Animal Sentience

The target article by Birch illustrates the practical difficulties with the “Animal Sentience Precautionary Principle” (ASPP) while presenting potential solutions. However, the ASPP will be difficult to use without guidelines detailing how evidence of sentience should be assessed. Moreover, extrapolating conclusions found for a single species to all species within an Order is problematic. Finally, I recommend that Birch demonstrate his ASPP framework using a controversial test case to help show how it could be used in real-world situations.

Dna Metabarcoding Reveals Provisioning Of Pollution-Sensitive Aquatic Insects, Resource Partitioning, And Dietary Shifts Among Breeding Neotropical Migratory Songbirds In A Riparian Habitat, Brian K. Trevelline

Electronic Theses and Dissertations

Elucidating the diet of Neotropical migratory birds is essential to our understanding of their ecology and to their long-term conservation. Beyond broad taxonomic or morphological categories, however, the diet of Neotropical migrants is poorly documented. Using the molecular techniques of DNA barcoding and next-generation sequencing, we elucidated the diet of Neotropical migratory songbirds breeding in the riparian zones of headwater Appalachian streams. This approach resulted in a genus- or species-level description of diets that improved the current understanding of how songbirds utilize aquatic prey resources in riparian habitats. Furthermore, our approach revealed that breeding songbirds partition prey resources within a …

Integrating Habitat Suitability Modeling And Radio Telemetry To Describe Habitat Use Of The Western Massasaugas, Sistrurus T. Tergeminus, In Texas, Mitchell R. Barazowski

Biology Theses

Habitat suitability modeling using the software package MaxEnt (Phillips, Anderson, & Schapire, 2006) is a popular method for describing the habitat of rare species. MaxEnt uses “presence only” data to develop models; however presence data are highly skewed towards areas of high detection probability and these areas may not represent the full range of habitat use. Thusly, predictions from models developed using only data from areas with high detection probability may not represent all suitable habitat. This study tested the ability of MaxEnt models developed using three different data sets to accurately describe Western Massasauga (Sistrurus t. tergeminus) habitat at …

Salvinia Molesta: An Assessment Of The Effects And Methods Of Eradication, Arti Lal

Master's Projects and Capstones

Salvinia molesta is an invasive aquatic fern. It is now the second worse aquatic invader in the world. Since the 1930s, it has invaded most tropical and some temperate countries. S. molesta plants grow vegetatively and can increase in size rapidly. S. molesta can form thick mats of up to 1-meter-thick. There are a number of ways these thick mats negatively affect the environment: 1) reduce light to benthic organisms, 2) reduce oxygen in the water column for other organisms, 3) accumulate as organic matter at the bottom of the water column, 4) decrease nutrients for other organisms, and 5) …

Examining The Combined Effects Of Dissolved Oxygen, Temperature, And Body Size On The Physiological Responses Of A Model Macrobenthic Polychaete Species, Capitella Teleta, Kelsey Burns Gillam

Dissertations

While the scientific community is in consensus that coastal systems are threatened by climate change, few climate change studies test the effects of more than one variable directly related to climate change. The dissolved oxygen (DO) levels of the ocean are currently subject to both global warming and eutrophication; 94% of all hypoxia zones are expected to experience >2°C increase by 2035. This dissertation aims to examine how a model organism responds to simultaneous thermal and DO stress involving four levels of DO (100%, 70%, 50%, and 20%) saturation and three temperatures (15°C, 20°C, and 25°C).

The polychaete, Capitella teleta …

An Analysis Of Morphometric Differentiation In Lake And River Populations Of The Emerald Shiner, Notropis Atherinoides, John J.V. Lang

Biology Theses

Understanding mechanisms that account for phenotypic variation has been of interest to biologists since the advent of Darwin’s theory of evolution by natural selection. It is now understood that adaptive divergence is a key driving force of intraspecific differentiation. Further, differences in habitat (e.g., flow regime, prey regime) have been shown to drive adaptive divergence in fish. For instance, fish inhabiting faster flowing water generally exhibit more fusiform bodies than their lake counterparts. Similarly, the partitioning of benthic and pelagic morphs generally results in smaller heads with the latter. This study used geometric shape analysis to assess morphological differences between …

Gulf Sturgeon (Acipenser Oxyrinchus Desotoi) Pre-Restoration Occupancy Patterns On Ship Island, Mississippi Sound With An Evaluation Of Designated Critical Habitat Use By Eastern And Western Population Segments, Page Elizabeth Vick

Master's Theses

Critical spawning and feeding habitat was designated for federally threatened, anadromous Gulf Sturgeon (GS) to aid in population recovery. This study examined GS occupancy, habitat use, and movement through critical habitat monitored by the Ship Island (SI) acoustic array during overwintering periods from 2011 to 2015 prior to MsCIP SI restoration. An occupancy index analyzed patterns of spatial and temporal habitat use of both western and eastern population segments (WPS and EPS, respectively) of GS on the SI array. The ends of SI along with the passes and cuts of the island, especially Dog Keys Pass (DKP), were occupied by …

Reproductive Schedule Of The Silver Shiner (Notropis Photogenis) In The Flint River Of Alabama, Kelly Hodgskins, Stephanie Greenleaf, Jonathan Hillman, Bruce Stallsmith

Southeastern Fishes Council Proceedings

Many river-dwelling species of fish are dependent upon and stimulated by fluctuations in river flow for successful reproduction. This is especially true of pelagophils, a reproductive guild whose eggs and larvae require free drifting on river currents for several days. Notropis photogenis (Silver Shiner) is a rheophilic species with a broad distribution from Ontario to the southeastern United States including northern tributaries to the Tennessee River in Alabama. Little is known of its reproductive biology. The purpose of this study was to describe aspects of reproductive biology such as timing and pattern of ovarian development and oocyte maturation of N. …

Foraging Behavior Of Tetramorium Caespitum In An Urban Environment: The Effect Of Food Quality On Foraging, Nicole A. Crofton, Sabrina R. D'Mello, Nene S. Sy

Student Publications

Animals' foraging strategies are directly related to their fitness. Proposed models of optimal foraging assume that animals strategize in terms of maximizing benefits over the cost of acquiring resources. Ants are social insects that are comparable in biomass to humans inhabiting the plant. As such, it is crucial to understand the foraging strategies of such an influential member of the ecosystem. With the ever-increasing rate of urbanization and human encroachment, it is even more important to consider the foraging patterns of species inhabiting urban areas. In this study we investigate optimal foraging strategies in the pavement ant, Tetramorium caespitum. Specifically, …

The Effect Of Survey Date On Assessing Calling Activity Of Hylidae, M. Kyle Brown, Amelia L. Russell, Adrian K.O. Hayes, Elliot P. Gibbs, Melissa A. Pilgrim

Journal of the South Carolina Academy of Science

No abstract provided.

A Novel Qtl Associated With Dwarf Bunt Resistance In Idaho 444 Winter Wheat, Jianli Chen, Mary J. Guttieri, Junli Zhang, David Hole, Edward Souza, Blair Goates

Green Canyon Environmental Research Area, Logan Utah

Dwarf bunt [Tilletia controversa J.G. Kühn [as ‘contraversa’], in Rabenhorst, Hedwigia 13: 188 (1874)] is a destructive disease of wheat (Triticum aestivum L.) that reduces grain yield and quality. A number of distinct genes conferring resistance to dwarf bunt have been used by breeding programs for nearly 100 years. However, few markers were identified that can be used in selection of dwarf bunt resistance. A recombinant inbred line (RIL) population derived from the bunt-resistant germplasm, Idaho 444 (IDO444), and the susceptible cultivar, Rio Blanco, was evaluated for phenotypic reaction to dwarf bunt inoculation in four trials in …

Population Dynamics And Genetic Differentiation Of The Threatened Freshwater Mussel Species Fusconaia Askewi, Fusconaia Lananensis, And Pleurobema Riddellii, Edith D. Plants-Paris

Biology Theses

North America has the most diverse freshwater mussel fauna in the world with approximately 300 species; unfortunately, extinction rates for freshwater mussels rivals the rates of many other groups of organisms. Population-level natural life history data is essential in the management of species of conservation concern, yet basic information about freshwater mussel life-history and demographic traits are unknown for many species. To further complicate matters, taxonomic uncertainty exists among some members of the group. The work detailed herein had two goals: to gain further understanding of the taxonomic relationship between Fusconaia lananensis and F. askewi by sequencing genes that had …

Guideline For Stakeholder Engagement On Aquatic Resource Management-Related Processes, Department Of Fisheries

Fisheries Occasional Publications

No abstract provided.

Incomplete Denitrification In Thermus Species, Chrisabelle Mefferd

UNLV Theses, Dissertations, Professional Papers, and Capstones

Members the bacterial genus Thermus have been shown to be incomplete denitrifiers, terminating with nitrite or nitrous oxide (N2O). However, the ability to carry out denitrification and the evolution of nitrogen oxide reductase genes in Thermus remains poorly understood. This study tests the hypothesis that incomplete denitrification is common in Thermus and seeks to uncover patterns in the evolution of denitrification pathways in Thermus. Denitrification capacity was determined in a collection of 25 strains representing ten species of Thermus and phylogenetic analysis was performed to determine whether denitrification genes evolved horizontally in Thermus. No strains in this study reduced nitrate …

Effects Of Shoreline Dynamics On Saltmarsh Vegetation, Shailesh Sharma, Joshua Goff, Ryan M. Moody, Ashley Mcdonald, Dorothy Byron, Kenneth L. Heck Jr., Sean Powers, Carl Ferraro, Just Cebrian

University Faculty and Staff Publications

We evaluated the impact of shoreline dynamics on fringing vegetation density at mid- and low-marsh elevations at a high-energy site in the northern Gulf of Mexico. Particularly, we selected eight unprotected shoreline stretches (75 m each) at a historically eroding site and measured their inter-annual lateral movement rate using the DSAS method for three consecutive years. We observed high inter-annual variability of shoreline movement within the selected stretches. Specifically, shorelines retrograded (eroded) in year 1 and year 3, whereas, in year 2, shorelines advanced seaward. Despite shoreline advancement in year 2, an overall net erosion was recorded during the survey …

Evaluating The Myth Of Allelopathy In California Blue Gum Plantations, Kristen Marie Nelson

Master's Theses

It is widely accepted that allelopathy is not only significant, but more or less singular, in the inhibition of understory vegetation in California Eucalyptus globulus (blue gum) plantations. However, there is no published documentation of allelopathy by blue gums against California native species. Here, we present evidence that germination and early seedling growth of five California native species are not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels. In the greenhouse, seeds were germinated in field-collected soil from mature blue gum plantations and the adjacent native, coastal scrub communities. In petri plates, seeds …

The Effects Of Urbanization On Leaf Breakdown Rates In A Rock Island Watershed, Jillian M. Jespersen, Laura Becker, Kortney Hix, C. Kevin Geedey

Celebration of Learning

The ability of streams to break down leaves is widely used as an indicator of stream health. In this study, a series of six streams within the Rock Island, Ill., watershed, which were similar in discharge, order, temperature and pH, were categorized as healthy or unhealthy based on chloride levels. This study was part of a broader study of the Rock Island watershed by Augustana. Maple leaves were collected shortly after abscission, weighed, packaged in mesh bags (approximately 5g per bag) and deployed in the streams for two- and four-week periods. After each time period, the leaves were removed, dried …

Plastic Pollution And The Global Throwaway Culture: Environmental Injustices Of Single-Use Plastic, Kristin L. Mcdermott

ENV 434 Environmental Justice

The global throwaway culture has created a cross-ecosystem plastic pollution injustice. The first to suffer this injustice will be the most vulnerable. Our oceans have become our dumpsters. The throwaway culture has created a disrespect of material goods that has turned the earth’s resources into rubbish after a single use. Eighty percent of the yearly 8 million tons of plastic that enter the ocean is single use plastic, such as plastic bottles, plastic shopping bags, or cigarette lighters.[1] Plastic has destroyed ecosystems, robbing impoverished communities of natural resources and of a healthy and safe living environment. First to suffer …

An Industrial Chemical Used In Coal-Washing Influences Plankton Communities In Freshwater Microcosms, Danielle Turner

Honors College Theses

In 2014, 4-methylcyclohexane methanol (MCHM), an industrial chemical used to wash coal, contaminated drinking water in 300,000 homes in West Virginia, USA and raised concerns about toxicity to humans and freshwater ecosystems. The Centers for Disease Control and Prevention determined that a concentration of 1 ppm was safe for human exposure. Despite the concern for human consumption, it is important to determine if MCHM has negative effects on aquatic organisms in contaminated water, particularly plankton communities that comprise the base of freshwater food webs. I exposed freshwater plankton communities in microcosms to 0, 0.5, 1 or 3 ppm MCHM under …

Relationships Between Nutrients, Periphyton Abundance, And Benthic Macroinvertebrate Scrapers In Ozark Highland Streams, Harrison Smith

Biological Sciences Undergraduate Honors Theses

We collected samples from seven Arkansas streams during the months of August 2014 and February 2015 with the objective of determining possible relationships between nutrients, periphyton abundance and benthic macroinvertebrates. We hypothesized that periphyton would be positively associated with nutrients, and that increases in periphyton biomass would increase the abundance and diversity of benthic scraper families. Samples were collected from three transects at each site. The periphyton was analyzed for carbon, nitrogen, phosphorus, and ash free dry mass and Chl-a content. Macroinvertebrates families belonging to the feeding group of grazers/scrapers were compared with water column and periphyton nutrient concentrations, as …

Assessment Of American White Pelican Predation And Reproductive Success Of Walleye In The Tamarac River, Mn, Jake Graham

Biology Graduate Theses

The Tamarac River is a major tributary of the Red Lakes MN, which provides an economically important multispecies fishery. The river experiences spring spawning migrations of northern pike, walleye, and white suckers. However, limited data exists related to reproductive success of fishes in the river. Furthermore, in the previous decade large congregations of American white pelicans (AWPE) have been observed using the Tamarac River as a foraging ground each spring. Assessing reproductive success of fishes in the Tamarac River provides a more holistic understanding of fish ecology in the river and the importance of the Tamarac River to the Red …

Stream Benthic Algal Relationships With Multi-Metric Indices Of Sensitivity, Exposure, And Vulnerability To Watershed Land Use Change, With An Emphasis On Unconventional Natural Gas Development, Hannah J. Verkamp

Biological Sciences Undergraduate Honors Theses

Unconventional natural gas (UNG) is harvested using a unique fossil fuel extraction method that uses horizontal drilling and hydraulic fracturing techniques. The combined methods have expanded the industry both nationally and globally, and development has the ability to transform landscapes and impact freshwater resources. Natural gas wells are often near streams, yet substantial knowledge gaps remain as to how and the extent to which development affects surface waters. Stream algal biomass can respond positively to anthropogenic stressors associated with different types of land use, including agriculture. Benthic algal biomass can also positively correlate with UNG well density and proximity to …

Depression In Thermal Performance Of Age-Structured Spirodela Polyrhiza Due To The Presence Of Rhopalosiphum Nymphaeae, Mitchell Matis, Chad Brassil, Colby J. Tanner

UCARE: Research Products

Thermal performance curves are keys components of population ecology. We performed this study to determine the effects of aphids on duckweed age-structured models across temperature. Results show a depression in birth rates and maturation of rates of duckweed in the presence of aphids. Regression analysis shows that this depression in maturation and birth is directly proportional to aphid growth rates across temperatures. This hints of the idea of modeling duckweed and aphid growth via nested thermal performance curves.

Tree-Mycorrhizal Associations Detected Remotely From Canopy Spectral Properties, Joshua B. Fisher, Sean Sweeney, Edward R. Brzostek, Tom P. Evans, Daniel J. Johnson, Jonathan A. Myers, Norman A. Bourg, Amy T. Wolf, Robert W. Howe, Richard P. Philllips

Biology Faculty Research

A central challenge in global ecology is the identification of key functional processes in ecosystems that scale, but do not require, data for individual species across landscapes. Given that nearly all tree species form symbiotic relationships with one of two types of mycorrhizal fungi – arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) fungi – and that AM- and ECM-dominated forests often have distinct nutrient economies, the detection and mapping of mycorrhizae over large areas could provide valuable insights about fundamental ecosystem processes such as nutrient cycling, species interactions, and overall forest productivity. We explored remotely sensed tree canopy spectral properties to …

Drip Irrigation: Saving Plants And Water Alike, Lewis University

Sustainability

No abstract provided.

Epigeal Fauna Of Bosque Protector Cerro Candelaria, Justine Albers

Independent Study Project (ISP) Collection

Pitfall traps are commonly used to sample epigeal fauna, and are especially utilized for the collection of ground-dwelling arthropods; however, this sampling method has yet to be employed in Cerro Candelaria, a protected cloud forest reserve in Tungurahua, Ecuador. Pitfall trap systems were established at two different sites in the reserve that differed in elevation and forest type. Although individuals from 4 different phlya, 11 classes and 17 orders were encountered over the duration of the study, pitfalls were most effective at sampling Coleoptera, which comprised 40% of the total catch across both sites. The two communities of beetle …

Molecular Analysis Confirming The Introduction Of Nile Crocodiles, Crocodylus Niloticus Laurenti 1768 (Crocodylidae), In Southern Florida, With An Assessment Of Potential For Establishment, Spread, And Impacts., Michael R. Rochford, Kenneth L. Krysko, Frank J. Mazzotti, Matthew W. Shirley, Mark W. Parry, Joseph A. Wasilewski, Jeffrey S. Beauchamp, Christpher R. Gillette, Edward F. Metzger Iii, Michiko A. Squires, Louis A. Somma

Papers in Herpetology

The state of Florida, USA, has more introduced herpetofauna than any other governmental region on Earth. Four species of nonnative crocodilians have been introduced to Florida (all since 1960), one of which is established. Between 2000–2014 we field-collected three nonnative crocodilians in Miami-Dade County, Florida, and one in Hendry County, Florida. We used DNA barcoding and molecular phylogenetics to determine species identification and native range origin. Also, we described diet, movement, and growth for one crocodile. Our molecular analyses illustrated that two of the crocodiles we collected are most closely related to Nile Crocodiles (Crocodylus niloticus) from South Africa, suggesting …

Gascoyne Demersal Scalefish Managed Fishery, Department Of Fisheries

Fisheries Occasional Publications

An operators’ guide to the management arrangements 1 September 2015 – 31 August 2016.

When Does Intraspecific Trait Variation Contribute To Functional Beta-Diversity?, Marko J. Spasojevic, Benjamin L. Turner, Jonathan A. Myers

Biology Faculty Research

Summary

1. Intraspecific trait variation (ITV) is hypothesized to play an important role in community assembly and the maintenance of biodiversity. However, fundamental gaps remain in our understanding of how ITV contributes to mechanisms that create spatial variation in the functional-trait composition of communities (functional Β-diversity). Importantly, ITV may influence the perceived importance of environmental filtering across spatial scales.
2. We examined how ITV contributes to functional Β-diversity and environmental filtering in woody plant communities in a temperate forest in the Ozark ecoregion, Missouri, USA. To test the hypothesis that ITV contributes to changes in the perceived importance of environmental filtering across …