Biology Commons^™

A Landscape On The Threshold Of Change: Patterns Of Soil Microbial Ecology Along Dynamic Geomorphic And Hydrologic Features In A Polar Desert, Kelli L. Feeser, David J. Van Horn, Heather N. Buelow, Daniel R. Colman, Theresa A. Mchugh, Jordan G. Okie, Egbert Schwartz, Cristina D. Takacs-Vesbach, Becky A. Ball, Andrew G. Fountain, Michael N. Gooseff, Joseph S. Levy, Maciej K. Obryk

Biology ETDs

The McMurdo Dry Valleys (MDV) of Antarctica are on the threshold of widespread landscape scale change due to increasing temperature and solar radiation and altered hydrology: buried ice is melting, the soil active layer is thickening, thermokarst features are developing along streams, water tracks are expanding, and lake levels are rising. These changes will impact the microbial communities found in each of the affected habitats. The purpose of this work is to first, understand the spatial distribution of soil bacteria in the MDV, specifically investigating the scale-dependent effects of environmental heterogeneity, and second, to perform surveys and coupled experiments to …

Landscape Scale: Inter- And Intraspecific Variation In Plant Interactions Along A Stress Gradient In The Sheep Range Of Nevada, Jordan Dowell

UNLV Theses, Dissertations, Professional Papers, and Capstones

Impending threats to shrubland ecosystems, posed by climate change, necessitate niche modeling efforts to project vegetation range shifts. However, efforts often remain unguided by individual-scale interspecific plant interactions. The stress gradient hypothesis posits that facilitation should increase in areas of high abiotic stress, only if the individuals are able to ameliorate the surrounding area via functional traits. The Sheep Range of Nevada was used to assess the role of functional traits as predictors of plant association. Larrea tridentata, Coleogyne ramosissima, and Artemisia nova were selected as shrubs with variable life history strategies and ranges in order to identify general patterns …

Mojave Desert Plant Community Long-Term Response To Disturbance, Dominic M. Gentilcore

UNLV Theses, Dissertations, Professional Papers, and Capstones

All vegetation communities have been shaped by disturbances. This dissertation consists of three separate chapters: Blackbrush (Coleogyne ramosissima) natural regeneration in the Great Basin-Mojave Desert Transition Zone on two fires, Long-term Response to Fire in Eastern Mojave Desert semi-arid shrubland communities, and an Annotated Checklist of Gold Butte National Monument in the Mojave-Colorado Plateau Transition Zone. The section on blackbrush natural regeneration was a long-term dataset from two fires in Basin and Range National Monument that burned in 2008 with monitoring events in 2009, 2010, 2011, 2018 and 2019. The monitoring documented some of the strongest post-fire regeneration for the …

Diet Composition And Mercury Exposure In Bank Swallows (Riparia Riparia) Breeding At Lakeshore And Aggregate Pits, Corrine S. V. Génier

Electronic Thesis and Dissertation Repository

Bank Swallows (Riparia riparia), a threatened species in Ontario, breed primarily in banks at lakeshores and in artificial aggregate pits. Inland pits may be ecological traps for this species, but the relative tradeoffs between these two nesting habitats are unknown. Availability of aquatic emergent insects at lakeshores may have associated nutritional benefits (e.g. Omega-3 fatty acids) and contaminants (e.g. mercury) that can directly influence juvenile growth. This study compares these breeding habitats to evaluate dietary differences as revealed by fatty acids, stable isotopes (δ¹³C, δ¹⁵N, δ²H), fecal DNA barcoding, and mercury. Lakeshore-nesting …

Impacts Of Shoreline Restoration And Source Of Nutrient Enrichment On Macrophytes And Epiphytic Algal Communities, Paige Marie Kleindl

Masters Theses

Macrophytes and their epiphytic algal communities are integral for optimizing littoral ecosystem functioning in lakes. Epiphytic algae’s placement on the plant’s surface can reduce light and nutrient availability (i.e., nitrogen and phosphorus) for the host macrophyte. Macrophyte and epiphytic algal proximity complicates these primary producer group interactions and responses to bioavailable nutrients in the water column or porewater. For example, epiphytic algae may have a competitive advantage over surface water nutrients compared to macrophytes, which may have a competitive advantage over porewater nutrients via root systems.

Muskegon Lake’s industrial history and designation as an Area of Concern prompted shoreline restoration, …

The Implementation Of Qpcr Beach Monitoring Methods: Analysis Of A Multi-Lab Validation Study And The Role Of Environmental Parameters On A Comparison Of Colilert And Qpcr Methods, Molly J. Lane

Masters Theses

Public beaches are routinely tested for potentially pathogenic bacteria to protect beachgoers from possible illness. An EPA approved method, Colilert™, used for testing E. coli in recreational water requires 18 – 22 hours before a result is reported but, recreators have already contacted unsafe water before the beach is closed. My study focused on a U.S. EPA proposed qPCR method (Draft Method C) to quantify E. coli in recreational waters that can provide same-day results. In Chapter 2, I examined the calibration procedure used to validate Draft Method C and compared standard curve intercept and slope estimates calculated with a …

Habitat Use Of The Climate-Sensitive Snowshoe Hare (Lepus Americanus) In The Manistee National Forest In Michigan’S Lower Peninsula, Spencer D. West

Masters Theses

Snowshoe hares (Lepus americanus) are a wide-ranging lagomorph that are important forest herbivores and a popular game species throughout their range. Across the southern boundary of their geographic range, snowshoe hares are experiencing population declines and possible extirpation due to increased predation pressure driven by climate change induced camouflage mismatch, competition for forage, degraded and fragmented habitat. One method of reversing the negative trends in snowshoe hare distribution is to increase and improve available hare habitat. A specific habitat analysis for local regions will most effectively advise managers how to target habitat management. I radio-collared 11 snowshoe hares in the …

Genetic Relationships Using Mitochondrial Versus Nuclear Markers: Is The Catfish Rag1 Gene Suitable For Species Differentiation In The Family Pangasiidae?, Huong Thanh Hoang

Graduate Theses and Dissertations

The Mekong River located in Southeast Asia is a global “hotspot” for aquatic biodiversity. It includes an extensive variety of fish species second only to the Amazon River in South America. Recent studies have revealed the impacts of anthropogenic and climate factors on this river system. Such impacts can result in the formation of barriers, which divide a species population and impede gene flow between separated sub-populations. Barriers influence evolutionary trajectories resulting in the generation of geographic variants or subspecies from an ancestral population. Catfish (Teleostei: Siluriformes) are a key species of the Mekong River ecosystem and are an essential …

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in …

A Multi-Scale Investigation Of Habitat Selectivity In Coastal Plain Stream Fishes, Hayley A. Robinson

Honors College Theses

Studying the habitat use of Coastal Plain fishes enables us to develop a deeper understanding of how fishes thrive in this highly variable environment. Based on previous research by Dr. Roberts and his students, Coastal Plain fishes seem to sort into two groups: (1) species selecting stream reaches that continue to flow throughout the summer (i.e., fluvial species [F]) and (2) species occurring in streams that may stop flowing in late summer (i.e., nonfluvial species [NF]). For this study, I took a detailed look at eight of these species, spanning the F-NF gradient, and asked which environmental variables (e.g., water …

Alternative Reproductive Tactics In Lake Michigan Populations Of Invasive Round Goby (Neogobius Melanostomus): How Fish Increase Fitness By Doing Less, Alex Florian, Steve Smit

Student Summer Scholars Manuscripts

Understanding the reproductive biology of invasive species is an important step in managing populations. Yet, little is known about the reproductive strategies of invasive round goby (Neogobius melanostomus) in Lake Michigan. For round goby, fertilization occurs externally in nests guarded by large “paternal” males. However, some males pursue alternative reproductive tactics (ARTs), where males sneak into a larger male’s nest and fertilize a portion of the eggs, these males are called “sneakers”. We investigated if the proportion of ARTs varies between sites and how that affects population dynamics of round goby. We caught 264 fish from 4 lakes along Eastern …

The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev

Electronic Thesis and Dissertation Repository

There is a collective prediction among ecologists that climate change will enhance phytoplankton biomass in temperate lakes. Yet there is noteworthy variation in the structure and regulating functions of lakes to make this statement challengeable and, perhaps, inaccurate. To generate a common understanding on the trophic transition of lakes, I examined the interactive effects of climate change and landscape properties on phytoplankton biomass in 12,644 lakes located in relatively intact forested landscapes. Chlorophyll-a (Chl-a) concentration was used as a proxy for phytoplankton biomass. Chl-a concentration was obtained via analyzing Landsat satellite imagery data over a 28-year period (1984-2011) and using …

Reorganization Of Surviving Mammal Communities After The End-Pleistocene Megafaunal Extinction, Anikó B. Tóth, S. Kathleen Lyons, W. Andrew Barr, Anna K. Behrensmeyer, Jessica L. Blois, René Bobe, Matt Davis, Andrew Du, Jussi T. Eronen, J. Tyler Faith, Danielle Fraser, Nicholas J. Gotelli, Gary R. Graves, Advait M. Jukar, Joshua H. Miller, Silvia Pineda-Munoz, Laura C. Soul, Amelia Villaseñor, John Alroy

School of Biological Sciences: Faculty Publications

Large mammals are at high risk of extinction globally. To understand the consequences of their demise for community assembly, we tracked community structure through the end- Pleistocene megafaunal extinction in North America.We decomposed the effects of biotic and abiotic factors by analyzing co-occurrence within the mutual ranges of species pairs. Although shifting climate drove an increase in niche overlap, co-occurrence decreased, signaling shifts in biotic interactions. Furthermore, the effect of abiotic factors on cooccurrence remained constant over time while the effect of biotic factors decreased. Biotic factors apparently played a key role in continental-scale community assembly before the extinctions. Specifically, …

Plasticity Of Foot Muscle And Cardiac Thermal Limits In The Limpet Lottia Limatula From Locations With Differing Temperatures, Terrance Wang, Richelle L. Tanner, Eric J. Armstrong, David R. Lindberg, Jonathon H. Stillman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Species distributions are shifting in response to increased habitat temperatures as a result of ongoing climate change. Understanding variation in physiological plasticity among species and populations is important for predicting these distribution shifts. Interspecific variation in intertidal ectotherms’ short-term thermal plasticity has been well established. However, intraspecific variation among populations from differing thermal habitats remains a question pertinent to understanding the effects of climate change on species’ ranges. In this study, we explored upper thermal tolerance limits and plasticity of those limits using a foot muscle metric and 2 cardiac metrics (Arrhenius breakpoint temperature, ABT, and flatline temperature, FLT) in …

Evaluating The Effect Of Time Of Day On Singing Behavior In Anna’S Hummingbirds, Adrian D. Macedo, Maxine R. Mota

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.

Dynamic Carbon Cycling In Muskegon Lake – A Great Lakes Estuary, Katie Lynn Knapp

Masters Theses

Ecosystem metabolism is the coupling of carbon and oxygen through photosynthesis and respiration. Gross primary production (GPP) is the carbon fixation by photosynthesis, ecosystem respiration (R) is carbon remineralization by bacterial and plankton respiration, and net ecosystem production (NEP) is the balance. Metabolism estimates determine if ecosystem is a sink or source of carbon to the atmosphere. When a lake has a positive NEP, or the GPP:R ratio is greater than 1, it is considered autotrophic and less carbon is being lost to the atmosphere than taken in, whereas if NEP is negative (GPP:R-1d^-1, respectively and the BOD …

Habitat Use And Tributary Occupancy Of The Threatened River Redhorse (Moxostoma Carinatum) In The Grand River, Mi, Usa., Nicholas Michael Preville

Masters Theses

The resiliency of our aquatic ecosystems hinges on our ability to protect the native species that reside within them. The river redhorse (Moxostoma carinatum) is one such example and populations have become low enough to warrant listing by the State of Michigan. Causes of decline include overfishing, habitat alteration, and lack of knowledge of basic life-history attributes including their use of non-spawning habitat and spawning locations. In order to understand the river redhorse’s habitat use we implanted 15 individuals with radio transmitters and tracked their locations over the course of a summer. Tagged river redhorse were found to …

An Assessment Of Periphyton Communities In Five Upper Peninsula Streams, Mi, Aaron Jeffrey Christiansen

Masters Theses

This project quantified lotic periphyton community change from May 2018-October 2018 in five, first and second-order Lake Superior tributary streams. Using periphyton communities, land use, geology, and abiotic factors pertinent to stream ecosystems we evaluated periphyton community succession. Using periphytometers, periphyton communities were collected and identified monthly to quantify community succession. Total phosphorus and total Kjeldahl nitrogen were measured monthly during the study. Depth, velocity, specific conductivity, and canopy cover were measured to quantify some of the physical factors within the streams. Nonmetric multidimensional scaling analysis indicated that the periphyton communities were similar between streams (ADONIS p-value =0.73) but was …

Using Landscape Genetics To Understand Connectivity Of An Island Population Of Eastern Massasauga Rattlesnakes (Sistrurus Catenatus), Nathan Kudla

Masters Theses

Populations that experience low levels of gene flow commonly display increased levels of inbreeding, lower genetic diversity, and reduced adaptive potential. Landscape genetics allows for spatial and genetic information to be analyzed simultaneously to better understand how the landscape influences gene flow. The eastern massasauga rattlesnake (Sistrurus catenatus) is a federally threatened viper found in wetlands throughout the Great Lakes region. Many remaining populations are small and isolated due primarily to habitat loss. Atypical from a range-wide perspective, eastern massasaugas on Bois Blanc Island (BBI), Michigan live in a relatively undisturbed landscape with a potential for high connectivity …

The Association Between Dietary Niche Variation In Rodents And Climate Change Across The Paleocene-Eocene Thermal Maximum, Hannah K. Vermeer

Masters Theses

Mammalian teeth play a crucial role in food acquisition and breakdown and are therefore closely tied to dietary niche. This study reconstructed the diet of early Paleogene paramyid rodents across the Paleocene-Eocene Thermal Maximum (PETM) climatic event in an effort to understand the role of climate in mammalian dietary niche change. Dietary niches were quantified using three dental topographic measures: Dirichlet normal energy, relief index, and orientation patch count rotated. A Kruskal-Wallis test was conducted over eight time periods to determine if each of the dental topographic measures (i.e., diet) varied over time. Regression analysis of these measures with climatic …

Evaluating Remote Site Incubators To Support Restoration Of Arctic Grayling In Michigan, Alan J. Mock

Masters Theses

Remote site incubators (RSIs) have been used to rear salmonid fish eggs along streams in the Pacific Northwest since the 1980s. Recently, the successful use of RSIs for Arctic Grayling Thymallus arcticus restoration in Montana has sparked a renewed interest to reestablish the species in Michigan. To support future reintroduction efforts of Arctic Grayling in Michigan, I evaluated RSIs in three Michigan streams during 2018 and 2019 using Rainbow Trout Oncorhynchus mykiss eggs (as surrogates for Arctic Grayling). My objectives were to: (1) compare hatching success between two different RSI designs (19-L vs. 265-L RSIs), and (2) test whether the …

Ecology Of Upland Snake Communities In Managed Montane Longleaf Pine Habitats Of Georgia, Miranda Gulsby

Master of Science in Integrative Biology Theses

Longleaf pine ecosystem decline in the Southeast United States has led to intensive land management implementation with the goal to benefit both the ecosystem and at-risk species. Addressing at-risk snake populations in these longleaf pine ecosystems, for instance, requires understanding both community and species level ecology of snakes in these managed forests. Data for snakes in the montane (mountain) longleaf pine habitats remains unclear since management practice implementation. Currently, intensive restoration of montane longleaf pine habitats is taking place within two Wildlife Management Areas (WMA) in the Raccoon Creek Watershed of Northwest Georgia, Sheffield and Paulding Forest. These areas differ …

Mechanisms For The Persistence Of The Coral Holobiont In The Warming Oceans Of The Anthropocene, Daniel G. Merselis

FIU Electronic Theses and Dissertations

Coral Reefs are rapidly deteriorating in response to an onslaught of human-mediated stressors. Just one stressor alone, climate change, may extirpate coral reef ecosystems within a human lifetime, threatening societal and ecological catastrophe. Reef-derived ecosystem services are crucial for sustenance, coastal protection, and economic prosperity in over 100 countries. Near-term human decisions will determine whether reef-corals, the ecosystems they engineer, the 25% of marine biodiversity they support, and the human communities that depend upon them can be protected. My dissertation aims to characterize the potential for corals' adaptive mechanisms to facilitate their continued survival- information which will only represent hope …

Coral Reef Change Detection In Remote Pacific Islands Using Support Vector Machine Classifiers, Justin J. Gapper, Hesham El-Askary, Erik Linstead, Thomas Piechota

Mathematics, Physics, and Computer Science Faculty Articles and Research

Despite the abundance of research on coral reef change detection, few studies have been conducted to assess the spatial generalization principles of a live coral cover classifier trained using remote sensing data from multiple locations. The aim of this study is to develop a machine learning classifier for coral dominated benthic cover-type class (CDBCTC) based on ground truth observations and Landsat images, evaluate the performance of this classifier when tested against new data, then deploy the classifier to perform CDBCTC change analysis of multiple locations. The proposed framework includes image calibration, support vector machine (SVM) training and tuning, statistical assessment …

Sex-Specific Personalities In The Purple Marsh Crab, Jillian Sterman, Jessica Barton, Panagiota Delmedico, Samantha Sweeney

DePaul Discoveries

Animals are considered to possess personalities when individuals differ in behavior, and these differences are consistent between situations. Several studies have identified personalities in diverse groups but less is known about personality variation between the sexes. In this study, we examined variation in two key personality traits (boldness, activity) in female and male purple marsh crabs (Sesarma reticulatum) using a semi-field approach. Specifically, we measured boldness and activity on two consecutive days using the same behavioral assays during each time point. Consistency (personality) was determined using Kendall’s coefficient of concordance based on Spearman correlation coefficients for each behavior. …

Effects Of Reduced Ph On Health Biomarkers Of The Seagrass Cymodocea Nodosa, Regan A. Mcenaney

DePaul Discoveries

Ocean acidification is a growing problem that may affect many marine organisms in the future. Within 100 years the pH of the ocean is predicted to decrease to 7.8, from the current ocean pH of around 8.1. Using phenolic acid levels as a stress indicator as well as respiration and chlorophyll content as a measure of health, the effect of lowering pH was tested on the seagrass, Cymodocea nodosa, in a controlled environment. Plant samples, water, and soil were taken from the Bay of Cádiz, Spain, and placed in aquaria in a temperature-controlled room. One control group was left …

High Heat Tolerance Is Negatively Correlated With Upper Thermal Tolerance Plasticity In North Eastern Pacific Nudibranch Mollusks, Eric J. Armstrong, Richelle L. Tanner, Jonathon H. Stillman

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Rapid ocean warming may alter habitat suitability and population fitness for marine ectotherms. Susceptibility to thermal perturbations will depend in part on plasticity of a species’ upper thermal limits of performance (CT_max). However, we currently lack data regarding CT_max plasticity for several major marine taxa, including nudibranch mollusks, thus limiting predictive responses to habitat warming for these species. In order to determine relative sensitivity to future warming, we investigated heat tolerance limits (CT_max), heat tolerance plasticity (acclimation response ratio), thermal safety margins, temperature sensitivity of metabolism, and metabolic cost of heat shock in nine species …

Hawk On Wire: Ecopoems By Scott T. Starbuck, Vivian M. Hansen

The Goose

Review of Scott T. Starbuck’s Hawk on Wire: Ecopoems

Effects Of The Invasive Zooplankter Bythotrephes Longimanus On The Aquatic Food Web In Green Bay, Lake Michigan, Arianna Neumeyer

Lawrence University Honors Projects

Bythotrephes longimanus, also known as the spiny water flea, is an invasive planktonic crustacean in the Great Lakes. Bythotrephes competes with fish for smaller planktonic prey. We sampled southern Green Bay, WI during the summers of 2017 and 2018 to determine population structure and dynamics of zooplankton in this important body of water. The biomass of Bythotrephes in 2017 express high numbers in mid-June and experience a mid-summer crash in early-July. Biomass then began to rise steadily until reaching their peak in late-August and September. We observed this crash in biomass for Bythotrephes and Leptodora in both 2017 and …

Play Behavior And The Development Of Boldness And Caution In Juvenile Belding’S Ground Squirrels (Urocitellus Beldingi), Madelene Shehan

Master's Theses

The ubiquity of play among juvenile mammals suggests it provides adaptive benefits, potentially through influences on the development of temperament in young animals. Juvenile Belding’s ground squirrels (Urocitellus beldingi) must balance competing demands for boldness and caution imposed by the fundamental trade-off between their short active season and their vulnerability to predation. In this study, I evaluated whether play helps to facilitate the development of an appropriate balance between boldness and caution in juvenile U. beldingi.I observed the play behavior of juvenile U. beldingiand conducted flight-initiation distance tests to measure boldness-caution at the beginning and toward …