Terrestrial and Aquatic Ecology Commons^™

Groundwater-Stream Connections Shape The Spatial Pattern And Rates Of Aquatic Metabolism, Anna Lupon, Lluís Gomez-Gener, Megan Fork, Hjalmar Laudon, Eugènia Martí, William Lidberg, Ryan A. Sponseller

Biology Faculty Publications

A longstanding challenge in stream ecology is to understand how landscape configuration organizes spatial patterns of ecosystem function via lateral groundwater connections. We combined laboratory bioassays and field additions of a metabolic tracer (resazurin) to test how groundwater-stream confluences, or "discrete riparian inflow points " (DRIPs), regulate heterotrophic microbial activity along a boreal stream. We hypothesized that DRIPs shape spatial patterns and rates of aquatic heterotrophic microbial activity by supplying labile dissolved organic matter (DOM) to streams. Laboratory bioassays showed that the potential influence of DRIPs on heterotrophic activity varied spatially and temporally, and was related to their DOM content …

Understory Epiphyte Hydrology: Analyzing Water Storage Capacity Of Epiphytes Along An Elevational Gradient In Western Ecuadorian Cloud Forest, Angelina Dodge

Independent Study Project (ISP) Collection

Epiphytes are defined as plants that grow on a host, often another plant, and acquire their nutrients and water from the atmosphere. As such is true, epiphyte composition is largely dependent upon atmospheric and thus climactic conditions. Due to high levels of atmospheric water availability that results from the frequent presence of mist, clouds, and high humidity, epiphytic plants grow and thus store water within the above ground region of the Andean cloud forest at levels higher than in any other ecosystem found in Ecuador. This study was done in hopes of revealing any trends of epiphytic water storage capacity …

Highly Pathogenic Avian Influenza A(H5n1) Virus Outbreak In New England Seals, United States, Wendy Puryear, Kaitlin Sawatzki, Nichola Hill, Alexa Foss, Jonathon J. Stone, Lynda Doughty, Dominique Walk, Katie Gilbert, Maureen Murray, Elena Cox, Priya Patel, Zak Mertz, Stephanie Ellis, Jennifer Taylor, Deborah Fauquier, Ainsley Smith, Robert A. Digiovanni, Adriana Van De Guchte, Ana Silvia Gonzalez-Reiche, Zain Khalil, Harm Van Bakel, Mia K. Torchetti, Kristina Lantz, Julianna B. Lenoch, Jonathan Runstadler

United States Department of Agriculture Wildlife Services: Staff Publications

We report the spillover of highly pathogenic avian influenza A(H5N1) into marine mammals in the northeastern United States, coincident with H5N1 in sympatric wild birds. Our data indicate monitoring both wild coastal birds and marine mammals will be critical to determine pandemic potential of influenza A viruses.

A Multiscale Linkage Between Riverscape And Fish Community Coevolution, Loren W. Stearman

Dissertations

Sediment dynamics are foundational to stream and watershed morphology. Yet aquatic ecologists have relied on an oversimplified model of sediment dynamics characterizing sediments as agents of stream bed burial, and which fails to describe many types of aquatic habitat evolution. In this dissertation I employ both fluvial geomorphic and ecological frameworks to gain a deeper understanding of how sediment dynamics shape stream morphology and fish community evolution at multiple scales. Using a paired historic and contemporary approach, I analyzed geomorphic evolution and fish community change in the Bayou Pierre, Mississippi, from the 1980s to recent. Patterns of erosion due to …

Cell Volume As A Determinant Of Virus-Mediated Population Growth In Ciliates, Jace Miller, John Paul Delong Phd

Honors Program: Senior Projects (Public)

Many protists and other small aquatic organisms consume virus particles, a behavior known as virovory. Some species of protists, such as the ciliate Halteria grandinella, can grow and divide using viruses as their sole food source. Other ciliate species have previously been shown to consume large quantities of viral particles, but it is unclear if they are able to support population growth with viruses alone. Because large ciliates have a higher energy demand, we hypothesize that they will be unable to support population growth on a virus-only diet. We fed nine ciliate species a diet of chloroviruses and found …

Assessment Of Largemouth Bass (Micropterus Salmoides) Condition Using Liver Histopathology, Health Parameters And Water Quality Of The Central Chattahoochee River Watershed, Kari Carmack Goodwin

Theses and Dissertations

The health of Largemouth bass from west-central Georgia was assessed using liver histopathology and the degree of tissue change index (DTC), hepatosomatic indices (HSI), relative weight, condition factors, and intersex. These health parameters as well as water chemistry data were compared across four bodies of water, three within the Chattahoochee watershed, and one pseudo-control located in the Flint watershed. Fish from Lake Oliver, Lake Harding, and West Point Lake had severely impacted liver health compared to Warm Springs National Fish Hatchery, with DTC rankings over 100 for the three lakes within the Chattahoochee watershed, demonstrating severely damaged livers. There was …

Center For Grassland Studies, March 2023

Center for Grassland Studies: Newsletters

Contents

New Assistant Director for The Center for Grassland Studies, David Wedin

Center for Grassland Studies Policy Advisory Committee

Director's Column by Jerry Volesky (Interim Director)

Congratulations December 2022 Graduates

New Grazing Lands Ecologist for Grassland Studies, Nic McMillan

New Administrative Associate for Grassland Studies, Ashley Branting

Apply Now for CGS Scholarships and Assistantship, https://grassland.unl.edu/grassland-systems/grazing-livestock-scholarships

New Guidelines for Reducing Eastern Redcedar in Grasslands by Dillon Fogarty

Year One Barta Brothers Ranch Collaborative Adaptive Management Update by Craig Allen

Nebraska Grazing Conference, August 8-9, 2023 by Daren Redfearn

Forty Years Reflection on Grassland Fire Weather by David Wedin

Nebraska Youth Range …

Lichens Of Ultramafic Rocks: A Multidisciplinary Approach To Understanding The Ecology Of An Understudied Organism In A Well-Studied System, Michael Mulroy

Master's Theses

Lichens are among the most prominent and successful life forms of metal-rich habitats, including ultramafic rocks and soils; however, research on lichens of ultramafic habitats is limited, especially on the North American continent. A review of the published literature on lichens of ultramafic substrates in North America yielded a total of 437 lichen species reported from ultramafic rocks and soils. Lichen assemblages of ultramafic substrates vary in composition and are dominated by acidophytic (low pH preferring) taxa with a minor, but consistent, basiphytic (high pH preferring) component. Species lists from ultramafic habitats in different geographic regions varied widely, suggesting that …

Remembering Paul Johnsgard, Linda R, Brown, Josef Kren

Zea E-Books Collection

Paul A. Johnsgard (1931–2021) was a friend of many, an artist, prolific author, teacher, and humble admirer of all living creatures. It was impossible to find someone at Nebraska Audubon Society or Nebraska Ornithologists’ Union meetings who did not know Paul Johnsgard. His more than 100 published books made him known not just in a community of ornithologists, birdwatchers, and bird lovers in the United States but also abroad. He was a world-renowned ornithologist and naturalist who remained deeply embedded in his local culture and its prairie environment.

We invited about 75 people to write a short memory of Paul. …

Prairie Dogs, Gary Witmer, Jon Grant, Kendra Cross

Wildlife Damage Management Technical Series

Prairie dogs (Cynomys spp.) occur throughout the prairie states of middle North America from Mexico northward into Canada. They occupy a variety of habitats from prairies to high mountain valleys and sage brush-dominated deserts. The most common species is the black-tailed prairie dog (Cynomys ludovicianus; Figure 1). Prairie dogs are considered a “keystone species.” They provide habitat for many other native, grassland species. Prairie dogs live in colonies or “towns” that can span hundreds to thousands of acres. Depending on the species, their presence is evident by their burrow system. Despite the many ecosystem benefits prairie dogs provide by modifying …

Elevated Estuary Water Temperature Drives Fish Gut Dysbiosis And Increased Loads Of Pathogenic Vibrionaceae, Alessandra L. Suzzi, Michael Stat, Troy F. Gaston, Nachshon Siboni, Nathan L. R. Williams, Justin R. Seymour, Megan J. Huggett

Research outputs 2022 to 2026

Marine water temperatures are increasing globally, with eastern Australian estuaries warming faster than predicted. There is growing evidence that this rapid warming of coastal waters is increasing the abundance and virulence of pathogenic members of the Vibrionaceae, posing a significant health risk to both humans and aquatic organisms. Fish disease, notably outbreaks of emerging pathogens in response to environmental perturbations such as heatwaves, have been recognised in aquaculture settings. Considerably less is known about how rising sea surface temperatures will impact the microbiology of wild fish populations, particularly those within estuarine systems that are more vulnerable to warming. We used …

Blanding’S Turtle (Emydoidea Blandingii): Species Conservation Assessment, Melissa J. Panella, Colleen Rothe-Groleau

Nebraska Game and Parks Commission: Publications

The primary goal in development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the Blanding’s turtle (Emydoidea blandingii) as a Tier 1 at-risk species. Some general management recommendations are made here regarding Blanding’s turtles; however, conservation practitioners will need to use professional judgment to make specific management decisions based on objectives, location, and a multitude of variables. This resource was designed to share available knowledge of this at-risk turtle that will aid in the decision-making …

American Eel (Anguilla Rostrata) And Other Fishes As Surveyed By Environmental Dna In The Bronx River And Hudson River Watershed, Sam C. Chin

Dissertations, Theses, and Capstone Projects

Mounting an effective response to the threats faced by freshwater fish may require expansions to aquatic biomonitoring in excess of what is feasible using the capture-based survey techniques currently relied upon by natural resource managers. Methods for analyzing environmental DNA (eDNA) are emerging as a minimally invasive and cost-effective approach for surveying fish and other organisms. By detecting taxon-specific DNA sequences recovered from environmental samples (e.g. water, sediment), eDNA methods are able to infer species presence from samples that can be collected rapidly with simple equipment. In many cases, eDNA detection rates of fish species have been shown to meet …

Refining The Moose Serum Progesterone Threshold To Diagnose Pregnancy, Madeline Struck, William J. Severud, Yvette M. Chenaux-Ibrahim, Edmund J. Isaac, Janine L. Brown, Seth A. Moore, Tiffany M. Wolf

Natural Resource Management Faculty Publications

Pregnancy determination is necessary for sound wildlife management and understanding population dynamics. Pregnancy rates are sensitive to environmental and physiological factors and may indicate the overall trajectory of a population. Pregnancy can be assessed through direct methods (rectal palpation, sonography) or indicated using hormonal assays (serum progesterone or pregnancy-specific protein B, fecal progestogen metabolites). A commonly used threshold of 2 ng/ml of progesterone in serum has been used by moose biologists to indicate pregnancy but has not been rigorously investigated. To refine this threshold, we examined the relationship between progesterone concentrations in serum samples and pregnancy in 87 moose ( …

An Evaluation Of Avian Influenza Virus Whole-Genome Sequencing Approaches Using Nanopore Technology, Hon S. Ip, Sarah Uhm, Mary Lea Killian, Mia K. Torchetti

United States Department of Agriculture Wildlife Services: Staff Publications

As exemplified by the global response to the SARS-CoV-2 pandemic, whole-genome sequencing played an important role in monitoring the evolution of novel viral variants and provided guidance on potential antiviral treatments. The recent rapid and extensive introduction and spread of highly pathogenic avian influenza virus in Europe, North America, and elsewhere raises the need for similarly rapid sequencing to aid in appropriate response and mitigation activities. To facilitate this objective, we investigate a next-generation sequencing platform that uses a portable nanopore sequencing device to generate and present data in real time. This platform offers the potential to extend in-house sequencing …

A Statistical Analysis Of The Change In Age Distribution Of Spawning Hatchery Salmon, Rachel Macaulay, Emily Barrett, Grace Penunuri, Eli E. Goldwyn

Spora: A Journal of Biomathematics

Declines in salmon sizes have been reported primarily as a result of younger maturation rates. This change in age distribution poses serious threats to salmon-dependent peoples and ecological systems. We perform a statistical analysis to examine the change in age structure of spawning Alaskan chum salmon Oncorhynchus keta and Chinook salmon O. tshawytscha using 30 years of hatchery data. To highlight the impacts of this change, we investigate the average number of fry/smolt that each age of spawning chum/Chinook salmon produce. Our findings demonstrate an increase in younger hatchery salmon populations returning to spawn, and fewer amounts of fry produced …

Landscape And Site Factors Drive Invasive Phragmites Management And Native Plant Recovery Across Chesapeake Bay Wetlands, Christine B. Rohal, Eric L. G. Hazelton, Eliza K. Mcfarland, Rebekah Downard, Melissa K. Mccormick, Dennis F. Whigham, Karin M. Kettenring

Watershed Sciences Student Research

Successful invasive plant management—where invaders are sufficiently reduced and diverse native plant communities recover—remains an elusive goal for land managers. The site- and landscape-scale drivers of variable management outcomes and vegetation recovery are poorly understood due to a lack of rigorous experiments that characterize longer term vegetation trends across contexts. We present the results of a five-year experiment across eight subestuaries of Chesapeake Bay, representing a gradient of watersheds with differing dominant land-use types and anthropogenic impacts, to evaluate invasive and native plant response to herbicide management. The focal invader, Phragmites australis (common reed), is one of the most aggressive …

Fire Impacts And Dynamics Of Seasonally Dry Tropical Forest Of East Java, Indonesia, Sutomo, Eddie J. B. Van Etten

Research outputs 2022 to 2026

Background: Seasonally dry tropical forests (SDTFs) are globally important ecosystems which receive less research attention compared to tropical rainforests but are equally under serious threat. The objectives of this paper are to characterize the vegetation structure, diversity and composition of SDTF of Baluran National Park, East Java, Indonesia, and to assess the impact of burning this SDTF and its post-fire recovery. Methods: In the field, we measured floristic composition and dominance at sites with different fire histories in both SDTF and adjacent savannas of Baluran. Remote sensing image analysis was also employed using the MODIS burn area product and various …

Assessing The Unionid Assemblage Of The Robert C. Byrd Pool, Ohio River, Ethan Hunter Bellamy

Theses, Dissertations and Capstones

Unionid mussels are the most imperiled taxa in the United States and are vastly understudied. The entire Robert C. Byrd (RCB) pool of the Ohio River is the study area. I selected sites from the 2019 and 2013 ORSANCO RCB pool assessments that utilize random site selection across the pool. I used SCUBA to survey and collect data on unionid diversity, reproduction, and habitat. I collected 1,083 individuals over 19 species in RCB pool. I compared results from RCB pool survey to two similar surveys conducted in Greenup Pool. Both richness and abundance in the Upper Section of Greenup Pool …

Characterizing The Vegetation And Effects Of Climate Change On Parris Island, A Sea Island Ecosystem, Cody Hart Goodson

Theses, Dissertations and Capstones

Coastal habitats provide many ecosystem services, protecting coastlines from storm surges and erosion, diminishing the effects of eutrophication, sequestering large amounts of carbon, and acting as vital wildlife habitat. Sea-level rise and increased storm surge intensity associated with climate change are increasingly disrupting coastal habitats. These disturbances can shift environmental gradients that drive the zonation of coastal vegetation types, driving habitat conversion. Monitoring coastal habitat conversion can improve our understanding of the dynamic effects of climate change on these landscapes. Therefore, our objectives for chapter 1 were to identify and describe the distributions of vegetation types present on Marine Corps …