Digital Commons Network^™

Fall Field Report, August–November 2025, W. Ross Silcock

Nebraska Bird Review

As in previous fall seasons, by far the most modifications to BONO came from late departure dates; around 87 species were included, no fewer than 13 of these setting record late dates, notably Eastern Whip-poor-will, Mountain Plover, Brown Thrasher (north), Henslow’s Sparrow (flight call only), and Orchard Oriole.

Although this is a Fall Seasonal Report, noted or suggested breeding activity is of interest. Exciting were the 2nd and 3rd presumed breeding records of Black-chinned Hummingbird and, in Dodge Co, the 5th record of breeding by Black-bellied Whistling-Duck. Perhaps the strangest west to east occurrence was a Golden Eagle adventure in …

Changes To The Nebraska Bird Review, Janis Paseka

Nebraska Bird Review

As of this issue, The Nebraska Bird Review has been in existence for 93 years, looking very much now as it did when it began in 1933. However, due to the increasing costs of printing and postage, there will be some changes in its future. Our newsletter, The Burrowing Owl, is already provided online to our members, in a user-friendly and informative form. Future issues of The Nebraska Bird Review will also utilize a digital format to offer a more timely and colorful publication.

This is the final issue for which Ross Silcock will be compiler of the seasonal …

Ogallala Fall Field Days, Janis Paseka

Nebraska Bird Review

The 2025 NOU Fall Field Days were held in Ogallala on September 26–28, with about 80 in attendance. The programs were held at the Quality Inn, and the meeting was planned by Boni Edwards, Dave Cunningham, and Paul Pearson. Field trips were led by Tobin and Keegan Brown, Jacob Cooper and UNK ornithology students, Joel Jorgensen and Stephen Brenner, T. J. Walker, and Thane Dinsdale. Destinations included various sites around Lake McConaughy, Lake Ogallala, Cedar Point Biological Station, Sutherland Reservoir SRA, Ash Hollow State Historical Park, Crescent Lake NWR, Arthur Co and various Sandhills lakes. The total species count was …

Impacts Of Nutrient Addition And Disturbance On Coastal Dune Arthropod Communities And Trophic Interactions, Kayla Beitzel

Graduate Theses and Dissertations (2019 - present)

Coastal dune ecosystems face ongoing threats from human-mediated disturbance and altered resource availability. Because these dunes provide critical habitat for many organisms, including shorebirds, beach mice, and arthropods, changes in disturbance regimes or resource availability can impact plant communities and higher trophic levels by altering plant richness and productivity, which in turn influence arthropod abundance and diversity. To examine how disturbance and nutrient addition affect arthropod communities, we established twenty 5×5 m plots on Dauphin Island, crossing mechanical disturbance with a 10 g m⁻² addition of nitrogen, phosphorus, and potassium, replicated across five experimental blocks. Arthropods were sampled using three …

Flower Color Variation And Its Maintenance: Experimental Ecology Of Serpentine-Adapted Leptosiphon Parviflorus Benth. (Polemoniaceae), Magdalene S. Lo

Master's Theses

Environmental heterogeneity can impose fluctuating selection pressures on species across space and time. If variations of a trait provide fitness benefits in certain environmental conditions but not others, these fitness tradeoffs under fluctuating selection could be a means of maintaining intraspecific variation. A common type of intraspecific variation is the production of anthocyanins, pigments responsible for red, pink, and blue colors in plants and that can also provide protection from abiotic stressors, such as water limitation and heavy metals. Leptosiphon parviflorus Benth. (Polemoniaceae, variable linanthus) is an annual wildflower whose individuals produce either pink or white flowers, and both flower …

Multiple Aspects Of Environmental Temperature Have Complex Interactions With Avian Parental Behavior To Influence Offspring Outcomes, William H. Kirkpatrick

Graduate Theses and Dissertations

Anthropogenic climate change is projected to shift not only average temperatures across the globe, but also the amount of thermal variation experienced in the natural environment. Exposure to shifts in averages and a wider range of thermal experiences will cause shifts in wildlife behavior. In avian species, behaviors exhibited during reproduction have implications for the well-being of their offspring. Here, I explore specific incubation behaviors in four species: Scaled Quail (Callipepla squamata), Northern Bobwhite Quail (Colinus virginianus), Tree Swallows (Tachycineta bicolor), and Eastern Bluebirds (Sialia sialis). I examined constancy, or the percentage of time on the nest, and off-bout duration, …

Why The Long Face? The Distribution And Niche Of The Imperiled Narrow-Faced Kangaroo Rat (Dipodomys Venustus), Garrett L. Gimbel

Master's Theses

Distribution models provide a practical use case of connecting ecological niche theory with species’ occurrence and assemblages. By explicitly linking Hutchinson’s “niche space” with geographic space researchers can gain valuable information on a species’ niche characteristics and interactions, thereby informing conservation and management practices. The narrow-faced kangaroo rat (Dipodomys venustus) is a highly understudied kangaroo rat species endemic to the central coast of California and is an ideal species to explore niche theory in distribution modeling. Three subspecies are currently recognized: The Santa Cruz kangaroo rat (D. v. venustus), the elephant-eared kangaroo rat (D. v. …

Drivers Of Faunal Communities In Isolated Wetlands: Local And Landscape Determinants Of Assemblages, Joshua Holbrook

All Dissertations

Ecological interactions such as predation are vital to shaping the distribution of organisms. For interactions to occur, organisms must undertake movement, such as dispersal, that places them in proximity to the organisms with which they may interact. Geographically isolated wetlands (GIW) are productive and biodiverse ecosystems, but little is known on broad geographic scales about the determinants of their fauna. Fishes have difficulty colonizing GIW, whereas amphibians and macroinvertebrates are adept overland dispersers – though they may be sensitive to top-down control by fishes. To better understand these phenomena, I sampled 10-20 wetlands each at nine regions in North and …

The Ecology Of Arthropod Rain In A Tropical Forest., Andrew Robert Seiler

Electronic Theses and Dissertations

Tropical forests are structured by complex vertical linkages and nutrient exchanges between canopy and understory habitats. These linkages include the downward flux of organisms, the movement of canopy fauna, and the recycling of nutrients through litter and organic matter deposition. This dissertation investigates arthropod rain and its role in connecting the canopy and forest floor processes in a lowland tropical forest in Panama. Chapter 2 quantifies “arthropod rain”, the fall of canopy arthropods into the understory. Using pan and pole traps, I measured the composition, abundance, and biomass of arthropods falling from the canopy and assessed environmental drivers of the …

What Limits Dryland Ecosystems? Patterns Of Soil Fertility And Resource Limitation In The Chihuahuan Desert, Dylan Stover

Open Access Theses & Dissertations

Human activities are substantially altering global resource cycles with widespread implications for biogeochemistry and ecosystem functioning globally. Drylands, regions where precipitation is outweighed by water losses, are especially sensitive to these large shifts in resource cycles due to their inherently low and variable resource availability. In these regions, resource availability and biological activity are often concentrated around plants – or fertile islands – and predominantly driven by pulses of water. However, our knowledge of the processes influencing biological productivity in drylands – patterns of soil fertility and resource limitation – remains lacking, and their unique biogeochemical and biological processes create …

Margalefidinium Polykrikoides Group Iii Va, Usa Strain Growth And Sac-Like Pellicle Cyst Dynamics, Eduardo Pérez Vega

OES Theses and Dissertations

Margalefidinium polykrikoides is a harmful cosmopolitan dinoflagellate that blooms in coastal waters. The effect of temperature and salinity on the growth of M. polykrikoides VA strain was examined using microscopy and growth models. M. polykrikoides Group III VA strain grew better at warmer temperatures and lower salinities than M. polykrikoides Group III NY strain, Group I Korea strain, and Japan strain (unknown group). Modelers need to use the temperature and salinity growth responses from M. polykrikoides Group III VA strain to better simulate and predict M. polykrikoides blooms in the Chesapeake Bay.

Dinoflagellates produce cysts as a strategy to withstand …

Arthropod Communities Associated With Endangered Physaria Thamnophila (Zapata Bladderpod) And Its Nurse Plants, Cesar Adrian Hinojosa

Theses and Dissertations

Physaria thamnophila is a federally endangered plant whose associated arthropods are understudied and poorly understood. This study surveyed environmental conditions and the arthropod community within the Arroyo Ramirez Tract of the Lower Rio Grande Valley National Wildlife Refuge, assessed which environmental factors influenced the arthropod community, and sought arthropod taxa statistically associated with Physaria thamnophila. Sticky cards and pitfall traps were deployed for a 7 day period, and vacuum samplings occurred quarterly over the span of a year to collect arthropods that were identified to order and family level for Coleoptera, Hymenoptera, and Lepidoptera. Biotic and abiotic surveys were performed …

Determination Of An Effective Natural Boxelder Bug (Boisea Trivittata) Repellent, Reyna Chavez

Theses and Dissertations

This study investigates the use of ecofriendly repellant alternatives to pest management to control boxelder bugs (Boisea trivittata). This bug gathers by the thousands on warm surfaces of exterior suburban homes during early fall and late spring. I determined bug repellency to turmeric oil (Curcuma longa), catnip (Nepeta cataria), citronella (Cymbopogon nardus), and lavender (Lavandula angustifolia). The treatments consisted of essential oils containing 20% methanol. All treatments demonstrated repellency of Boxelder bugs. Citronella was the most effective and had the highest level of repellency range of 90-99%. Catnip was the least effective with a repellency range of 63-82%.

Seagrass Preference Among Pinfish In The Lower Laguna Madre, Nathaniel Garza

Theses and Dissertations

Pinfish (Lagodon rhomboides) is a common estuarine fish species found from Massachusetts to the Yucatan, Mexico. As juveniles, pinfish spend a significant portion of their life in coastal seagrasses which provide both shelter from predators and food. Along the Texas coast, there are three major species of seagrass- turtle grass (Thalassia testudinum), manatee grass (Syringodium filiforme) and shoal grass (Halodule wrightii) that differ in structural complexity. The goal of this study was to determine if pinfish associate more with one seagrass species than the others. A year-long field study was completed using twelve sample sites in the Lower Laguna Madre, …

Bricks, Bushes, And Bones: Urbanization Influence On Western Fence Lizard (Sceloporus Occidentalis) Morphology And Performance, Daisy P. Xiong

Electronic Theses, Projects, and Dissertations

With increasing urbanization due to rising human populations, organisms may be forced to adapt rapidly to changing environments. Urbanization is replacing natural surfaces with more impervious substrates which can result in morphological changes affecting organismal locomotion, then also impact fitness. This study compares urban and natural habitat impact on Western Fence Lizards (Sceloporus occidentalis) and their adaptations in such settings. We captured lizards from three locations in inland Southern California with both urbanized and natural habitats in order to compare the morphological differences between lizards, and then measured their performance to determine the possible impacts from their morphology. …

Plant Community Responses To Wildfire, Timber Thinning, And Bison Reintroduction On The Northern Great Plains, Ethan H. Van-Derpoel

All Theses

The Northern Great Plains (NGP) is one of the largest intact grasslands remaining in the world. These two studies examine a few of the ecological concerns on the NGP today. First, the woody encroachment of conifers into grasslands and the effects of wildfires. Second, the effects of bison (Bison bison) reintroduction on plant communities. In Chapter 1, this study aims to examine the effects of wildfire and mechanical timber thinning, using a two-by-two factorial design, on plant community responses and forage quality in the Bull Mountains area of central Montana, USA. We found that our treatments had varying …

Golden Eagle Predation Of Greater Sage-Grouse On Diamond Mountain Plateau, Victoria E. Thorpe

All Graduate Theses and Dissertations, Fall 2023 to Present

Predation and the perceived risk of predation can have major impacts on prey populations. Golden Eagles are considered one of the main predators of adult greater sage-grouse. Sage-grouse populations have been declining for decades throughout the West and wildlife managers are concerned about the impacts of golden eagles on sage-grouse. We investigated the nonconsumptive effects of golden eagles on sage-grouse by conducting observational surveys for golden eagles, sage-grouse, and other predators at sage-grouse lek sites near Vernal, Utah during the sage-grouse breeding season from 2022–2024. Additionally, we examined the prevalence of sage-grouse in golden eagle diet using DNA metabarcoding of …

Taxonomy Of Endophytic Fungi Associated With Vallisneria Neotropicalis, Md. Arafat Rashid

Graduate Theses and Dissertations (2019 - present)

This study presents the first comprehensive taxonomic and ecological investigation of endophytic fungi (EF) associated with the submerged aquatic macrophyte Vallisneria neotropicalis in the southern United States. Over a 12 month period, from April 2023 to March 2024, leaf samples were collected from two distinct sites in Mobile Bay, Alabama a disturbed, brackish Causeway location and a cleaner, less impacted site at Meaher State Park. Using culture dependent methods, a total of 257 fungal endophytes were isolated from 1,200 leaf segments. All isolates belonged to the phylum Ascomycota, distributed across 3 classes, 6 orders, 10 families, and 19 taxa. The …

Exploring Life History Trade-Offs In The Facultative Eusocial Bee Megalopta Genalis, Ana Gutiérrez Zuluaga

All Graduate Theses and Dissertations, Fall 2023 to Present

Organisms face many trade-offs in how to invest in these traits. One example is the trade-off between reproduction and longevity. Queens of social insects seem to escape this trade-off, producing thousands of eggs daily, despite having a longer lifespan than their workers. Some hypotheses have been proposed to explain this phenomenon, such as an evolutionary change in the molecular pathways that regulate queen investment in maintenance, growth, and reproduction. An alternative hypothesis suggests that the tradeoffs are rarely observed in queens due to the extensive resources provided by the help of workers. While these hypotheses have supporting evidence, they have …

Integrating Manager Perspectives Into The Evaluation Of Wetland Revegetation Strategies, Loren F. Taylor

All Graduate Theses and Dissertations, Fall 2023 to Present

Ecological restoration is the process of assisting the recovery of an ecosystem that has been degraded and is dependent on complex and context-specific decisions. The decision-making process influencing restoration is rarely examined alongside ecological processes. There is a need for research that incorporates the social, economic, institutional, and logistical considerations that shape real-world practices, as well as ecological processes. Decisions made by restoration practitioners and land managers (hereon “manager”) are challenged by the lack of information shared regarding the practical constraints (e.g., cost, labor, specialized equipment) they face. Revegetation, particularly in wetlands, poses challenges due to site conditions and degradation …

Impacts Of Halophila Stipulacea Invasion On Organic Matter Dynamics In Thalassia Testudinum Dominated Seagrass Meadows, Puerto Rico, Jonathan D. Herald

Master's Theses

Halophila stipulacea (Forsskål & Niebuhr) is a tropical seagrass native to the Red Sea, Persian Gulf, and Indian Ocean. In 2002, invasive populations of H. stipulacea were identified in the Caribbean Sea where it now forms large meadows, displaces native seagrasses, alters invertebrate and fish communities, and potentially affects organic matter dynamics in invaded meadows. This study investigated differences in organic matter dynamics between meadows of H. stipulacea and native Thalassia testudinum within the Jobos Bay National Estuarine Research Reserve (JBNERR) on the southern coast of Puerto Rico. From March 2023-March 2024, sampling was conducted across four sites to investigate …

Effects Of Urbanization On The Population Genetics And Morphology Of The White-Footed Mouse (Peromyscus Leucopus) Across An Urban–Rural Gradient, Sydney A. Morton

Master's Theses

Urbanization alters landscapes in ways that can reshape wildlife populations by changing habitat connectivity, resource availability, and selective pressures. To investigate how urbanization influences both genetic differentiation and morphology in small mammals, I examined Peromyscus leucopus (PELE) across an urban–rural gradient in northern Georgia. Using RADseq SNP data from PELE individuals across 13 sites, I quantified pairwise genetic differentiation (F_ST) and tested how various environmental variables, including impervious surface cover, human population density, and tree canopy cover, predict genetic differentiation after accounting for geographic distance. Genetic differentiation increased with geographic distance and, after controlling for isolation by …

Birds In Changing Landscapes: Community Diversity And Breeding Phenology, Lindsay Peria

Master's Theses

Humans are altering the environment in varied and widespread ways. Increasing urban and agricultural development causes changes to habitat and resource availability as well as changes to the sensory environment via light and noise pollution. Climate change also causes more extreme temperature anomalies, storms, and droughts that challenge birds in a multitude of ways. In this thesis, we assessed these impacts of these changes on a local and continental scale. In the first chapter, we assessed the impact of natural, anthropic, and structural characteristics of viticultural land on both taxonomic and structural avian diversity. Loss of habitat from agriculture is …

Testing For Local Adaptation In Sympatric Monkeyflowers Growing In Serpentine Seeps And Adjacent Rock Outcrops, Avin Niknafs

Master's Theses

Divergent selection across heterogeneous environments can drive ecological differentiation and the evolution of locally adapted populations, even when gene flow occurs. We tested for local adaptation between two sympatric monkeyflowers, Erythranthe guttata and E. serpentinicola (formerly Mimulus), which co-occur on the central coast of California. Erythranthe guttata is a perennial species primarily found in moist serpentine seeps, whereas E. serpentinicola is an annual species restricted to adjacent serpentine rock outcrops. Using a reciprocal transplant experiment with second-generation, greenhouse-derived seed, we quantified germination, survival, and reproductive success across contrasting microhabitats. We further evaluated the relative contributions of species, lineage, …

Robustness Of Network Inference Algorithms Under Network Class Misspecification, Roberto Ceja

Electronic Theses, Projects, and Dissertations

Inferring phylogenies in the presence of hybridization remains a difficult problem. As a result, many current methods for reconstructing phylogenetic networks are restricted to a simple class of networks known as level-1. This restriction arises from theoretical considerations rather than empirical evidence, with real data possibly arising from complex networks. In this work, we evaluate the robustness of two level-1 network inference methods, SNaQ and NANUQ+, through a simulation study, when the input data originates from a more complex network. Specifically, we investigate whether these methods can accurately recover important features of the true species network, such as the circular …

Decision Support To Meet Objectives For Water And Fisheries Management In Large River And Estuarine Systems, Phaedra Elizabeth Budy

Funded Research Records

No abstract provided.

Immunological Surveillance Against Cancer Across Mammals, Orsolya Vincze, Piotr Minias, Alexandre Corthay, Fernando Colchero, Jean-François Lemaître, Louise Maille, Tamás Malkócs, Justus Hagemann, Dalia A. Conde, Samuel Pavard, Antoine M. Dujon, Beata Ujvari, Frédéric Thomas, Amy M. Boddy, Carlo C. Maley, Damien Chevallier, Tuul Sepp, Thomas Pradeu, Mathieu Giraudeau

Presidential Fellows Articles and Research

Contrary to expectations based on their higher cell numbers, larger and longer-lived species do not face dramatically increased risk of cancer. This strongly suggests that evolution has fashioned natural cancer resistance mechanisms, yet our knowledge remains limited on what these mechanisms might be. The cancer immunological surveillance hypothesis, proposed by Burnet and Thomas in the 1950s, highlights immunity as a key factor determining species-specific cancer resistance. Here we address the original, evolutionary interpretation of this hypothesis by investigating the relationship between cancer mortality risk and markers of efficient antigen presentation. Our results show that the expansion of the MHC class …

A Silver Spoon Effect Reduces Lifetime Fitness In A Declining Loon Population, Walter H. Piper, Claudia Kodsuntie, Hayden Walkush

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A complete understanding of factors that influence animal fitness requires that we measure not only those occurring day to day in the life of an animal but also those that operate on longer time scales. Here, we investigated silver spoon effects (fitness impacts resulting from conditions faced early in life) and carryover effects (fitness impacts caused by environmental factors in a previous season) in a northern Wisconsin population of the common loon (Gavia immer). The mass of a loon chick divided by its age, an indication of food it received from its parents in its first 4 to …

The Effect Of Noise Pollution On The Diversity And Abundance Of Bird Species At Different Locations At Warner Parks, Nashville, Tn, Jeremy T. Little, Wyatt L. Fooks, Darlene Panvini, Jackson Whiteside

Science University Research Symposium (SURS)

Noise pollution is a significant abiotic factor that can alter bird biodiversity and abundance of birds in urbanized areas. A new road is proposed through a relatively untouched area of Warner Parks in Nashville, TN, which may affect the bird community. Acoustic Song Meters were used to monitor bird sounds and soundscapes in the proposed road site and two areas of the park with different levels of noise pollution (roadside=high noise; isolated=low noise) for three weeks. Recordings were analyzed to determine bird species and abundance at each site to predict how increasing noise pollution may affect bird diversity in the …

Surviving The Seasons: Climate And Time Effects On Native Songbirds, Essence Donaldson, Todd Hoskinson, John Niedzwiecki

Science University Research Symposium (SURS)

Bird populations across North America have declined sharply in recent decades due to habitat loss, climate change, and changes in food availability. As bird numbers fall, ecosystems lose essential pollinators, seed dispersers, and insect predators. Long-term monitoring of bird populations is vital for understanding how environmental changes influence their survival and abundance. This study examines capture data from a long-term bird banding station at Percy Warner Nature Center in Nashville, Tennessee, focusing on five native species: Northern Cardinal (NOCA), American Robin (AMRO), American Goldfinch (AMGO), Tufted Titmouse (TUTI), and Carolina Chickadee (CACH), from fall 1983 to fall 2023. We analyzed …