Terrestrial and Aquatic Ecology Commons^™

An Efficient Method Of Evaluating Multiple Concurrent Management Actions On Invasive Populations, Amy J. Davis, Randy Farrar, Brad Jump, Parker Hall, Travis Guerrant, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Evaluating the efficacy of management actions to control invasive species is crucial for maintaining funding and to provide feedback for the continual improvement of management efforts. However, it is often difficult to assess the efficacy of control methods due to limited resources for monitoring. Managers may view effort on monitoring as effort taken away from performing management actions. We developed a method to estimate invasive species abundance, evaluate management effectiveness, and evaluate population growth over time from a combination of removal activities (e.g., trapping, ground shooting) using only data collected during removal efforts (method of removal, date, location, number of …

2022 Gray Wolf Questions And Answers, United States Fish And Wildlife Service

United States Fish and Wildlife Service: Publications

2022 Gray Wolf Questions and Answers

What does the February 10, 2022, ruling mean?

How does this ruling affect wolves in the Northern Rocky Mountains?

When does the court decision to vacate the delisting rule go into effect?

What is the legal status of gray wolves as of this ruling?

Is the Service continuing its status review of wolves in the western United States?

Is emergency listing an option for the Northern Rocky Mountain population?

Are wolf hunts going to stop as a result of the court decision?

How does this ruling affect wolves in Yellowstone National Park?

Where can …

Economics Of Cormorant Predation On Catfish Farms, Carole Engle, Ganesh Kumar, Terrel Christie, Brian S. Dorr, Brian Davis, Luke Roy, Anita Kelly

United States Department of Agriculture Wildlife Services: Staff Publications

The Double-crested Cormorant is the primary avian predator on catfish farms causing significant economic losses primarily due to 1) on-farm expenditures related to bird-management activities and 2) value of the catfish lost to cormorants. This comprehensive economic study quantified these two economic effects by surveying catfish farms in the delta regions of Mississippi and Arkansas. On-farm expenditures for bird scaring were used to quantify bird-management costs. Economic losses from fish consumed by cormorants were quantified by evaluating data from field studies of the abundance, distribution, and diet of cormorants in the Mississippi delta. This study found that catfish farmers …

Effects Of Green Crab (Carcinus Maenas) Across Variable Densities Of Eelgrass (Zostera Marina), Kimberly Alexis Brown

Dissertations and Theses

Eelgrass (Zostera marina) plays a critical role in estuarine ecosystem function by sustaining a variety of marine and freshwater species, but it's increasingly threatened by the aggressive non-native green crab (Carcinus maenas). The abundance of C. maenas is on the rise within the coastal environment of Oregon and it is imperative to know how these populations will affect the long-term health of Z. marina. C. maenas have been linked to declines in Z. marina coverage and shellfish abundance, but there has been no research on to what extent the density of Z. marina affects its …

Fish And Invertebrate Use Of Restored Vs. Natural Oyster Reefs In A Shallow Temperate Latitude Estuary, Jonathan H. Grabowski, Christopher J. Baillie, Adam Baukus, Rachael Carlyle, F. Joel Fodrie, Rachel K. Gittman, A. Randall Hughes, David L. Kimbro, Juhyung Lee, Hunter S. Lenihan, Sean P. Powers, Kevin Sullivan

University Faculty and Staff Publications

Coastal marine habitats continue to be degraded, thereby compelling largescale restoration in many parts of the world. Whether restored habitats function similarly to natural habitats and fully recover lost ecosystem services is unclear. In estuaries, oyster reefs have been degraded by multiple anthropogenic activities including destructive fishing practices and reduced water quality, motivating restoration to maintain oyster fisheries and other ecosystem services, often at relatively high cost. We compared fish and invertebrate communities on recently restored (0–1 year post-restoration), older restored (3–4 years post-restoration), and natural oyster reefs to determine if and when restored reefs support functionally similar faunal communities. …

No Panacea Attractant For Wild Pigs (Sus Scrofa), But Season And Location Matter, Nathan P. Snow, Caitlin A. Kupferman, Michael J. Lavelle, Kim M. Pepin, Madeline H. Melton, Whitney J. Gann, Kurt C. Vercauteren, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are a prolific invasive species throughout many regions of the world that cause extensive economic and environmental damage. Trapping is a common strategy for reducing their populations with baits (i.e., food) and attractants (e.g., scents) used to lure wild pigs into traps. However, there is little information on which scent attractants may attract wild pigs more readily and rapidly across regions and seasons. We examined 60 scent attractants for wild pigs that could be used to increase trapping success across three seasons (winter, spring, and fall) and in two geographic regions, including a warm …

Predation Thresholds For Reintroduction Of Native Avifauna Following Suppression Of Invasive Brown Treesnakes On Guam, Robert M. Mcelderry, Eben H. Paxton, Andre V. Nguyen, Shane R. Siers

United States Department of Agriculture Wildlife Services: Staff Publications

The brown treesnake (BTS) (Boiga irregularis) invasion on Guåhan (in English, Guam) led to the extirpation of nearly all native forest birds. In recent years, methods have been developed to reduce BTS abundance on a landscape scale. To help assess the prospects for the successful reintroduction of native birds to Guåhan following BTS suppression, we modeled bird population persistence based on their life history characteristics and relative sensitivity to BTS predation. We constructed individual-based models and simulated BTS predation in hypothetical founding populations for each of seven candidate bird species. We represented BTS predation risk in two steps: …

Conserving Endangered Black-Footed Ferrets: Biological Threats, Political Challenges, And Lessons Learned, Travis M. Livieri, Steven C. Forrest, Marc R. Matchett, Stewart Breck

United States Department of Agriculture Wildlife Services: Staff Publications

There may be few stories in the annals of wildlife management that are as dramatic as the near demise and comeback of the black-footed ferret (Mustela nigripes). Endemic only to North America, this charming little carnivore found only in the continent’s central grasslands was hardly known to science until the mid-20th century. By then, vast colonies of the prey it depended on for food and shelter, the prairie dog (Cynomys spp.), had been wiped out through disease (sylvatic plague) and an agricultural industry with little tolerance for burrowing and grazing rodents. At its low point, the species’ …

Spatial And Temporal Variability Of Mercury In Upper And Lower Red Lake Walleye, Tyler Orgon

Biology Graduate Theses

Mercury is a global pollutant that is released into our environment by natural and anthropogenic processes resulting in extensive studies conducted on mercury cycling in aquatic ecosystems which has led to the issuance of human-health-based fish-consumption advisories. We examined total mercury concentrations in Walleye Sander vitreus from Upper and Lower Red Lakes, located in north central Minnesota, between 2019 and 2020. Upper and Lower Red Lake form a contiguous water body consisting of two large (483.1 and 665.6 km2, respectively) basins that are naturally connected by a 1.4 km-wide strait. Both basins are important fisheries for recreation, subsistence, and commercial …

"Reeling In" Juvenile Sportfish Through Coastal Habitat Restoration: Population, Community, And Trophic Responses In The Indian River Lagoon, Florida, Jennifer Loch

Electronic Theses and Dissertations, 2020-2023

Coastal habitats provide crucial nursery habitat for predatory fishes, but they are in decline worldwide, impacting economically important fisheries. Habitat restoration can simultaneously mitigate the effects of habitat loss and benefit predators (e.g., sportfish), although this relationship is understudied. Here, the response of juvenile sportfish to oyster reef and living shoreline restoration is compared to controls in the Indian River Lagoon, Florida prior to and following restoration for up to three years through examination of community (diversity, assemblage), population (abundance), biometric (size, body condition), ontogenetic, and trophic (gut contents, stable isotopes) dynamics. Stable isotopes were used to quantify dietary history, …

Foot Injuries In Michigan, Usa, Gray Wolves (Canis Lupus), 1992–2014, Daniel J. O'Brien, Dean E. Beyer Jr., Erin Largent, Julie R. Melotti, Caitlin N. Ott-Conn, Donald H. Lonsway, Thomas M. Cooley, Robert Atkinson, Michelle Clayson, Kelly A. Straka

United States Department of Agriculture Wildlife Services: Staff Publications

The range of gray wolves (Canis lupus) in the contiguous US is expanding. Research and monitoring to support population recovery and management often involves capture via foothold traps. A population-level epidemiologic assessment of the effect of trap injuries on wolf survival remains needed to inform management. We describe the baseline rate, type, and severity of foot injuries of wolves born 1992–2013 in Michigan’s Upper Peninsula, evaluate the reliability of field-scoring trap-related injuries, and the effect of injuries on wolf survival. We assessed foot injuries by physical and radiographic exam at postmortem and/or time of capture for 351 wolves using the …

Olfactory Lures In Predator Control Do Not Increase Predation Risk To Birds In Areas Of Conservation Concern, Page Klug, Amy A. Yackel Adams, Robert N. Reed

United States Department of Agriculture Wildlife Services: Staff Publications

Context. Lethal control of predators is often undertaken to protect species of conservation concern. Traps are frequently baited to increase capture efficacy, but baited traps can potentially increase predation risk by attracting predators to protected areas. This is especially important if targeted predators can escape capture due to low trap success. Snake traps using live mouse lures may be beneficial if traps effectively remove snakes in the presence of birds and do not attract additional snakes to the area.

Aims. The present study evaluated whether mouse-lure traps in areas occupied by birds (simulated by deploying birdlure traps) could influence predation …

Wild Pig Removal Reduces Pathogenic Bacteria In Low-Order Streams, Sara A. Bolds, B. Graeme Lockaby, Latif Kalin, Stephen S. Ditchkoff, Mark D. Smith, Kurt Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive wild pig populations have undergone enormous increases in the United States and particularly across the southern U.S. in recent years. High fecundity rates and abilities to adapt quickly to varied habitats have enabled pig populations to become entrenched and difficult to eliminate. The pigs cause many negative impacts on ecosystems including degradation of water quality through infusion of fecal contamination and other non-point source pollutants. Our goal was to determine the effects of pig removal on water quality in streams that were known to be significantly polluted by pig activity Bolds (J Environ Qual 50: 441–453, 2021). We compared …

Phenotypic Plasticity Of Geographically Central And Peripheral Populations Of Jefferson Salamanders (Ambystoma Jeffersonianum) In Response To Simulated Climate Change, Aaron Devine

Online Theses and Dissertations

Climate change will elicit various species responses as it causes habitats to change. Species with limited dispersal must respond to these changes “in place”, yet some biogeographical hypotheses indicate isolated and less abundant populations experience reduced gene flow and genetic diversity that may limit phenotypic plasticity, contrasting with evidence suggesting more variable habitats select for increased plasticity in peripheral populations. To gain insight into associations between range position and intensity of plasticity, mesocosm experiments were done to assess plasticity in larval growth, size at, and time to, metamorphosis, and survivorship in larval Ambystoma jeffersonianum salamanders from geographically core and peripheral …

Plague Risk In The Western United States Over Seven Decades Of Environmental Change, Colin J. Carlson, Sarah N. Bevins, Boris V. Schmid

United States Department of Agriculture Wildlife Services: Staff Publications

After several pandemics over the last two millennia, the wildlife reservoirs of plague (Yersinia pestis) now persist around the world, including in the western United States. Routine surveillance in this region has generated comprehensive records of human cases and animal seroprevalence, creating a unique opportunity to test how plague reservoirs are responding to environmental change. Here, we test whether animal and human data suggest that plague reservoirs and spillover risk have shifted since 1950. To do so, we develop a new method for detecting the impact of climate change on infectious disease distributions, capable of disentangling long-term trends (signal) and …

Analysis Of Hematocrit Levels In Walleye Sander Vitreus From Similar Waterbodies, Alyssa Hauser

Journal of Earth and Life Science

Walleye Sander vitreus are a popular fish among anglers and hold a prominent place in Minnesotan’s identity as their state fish. Because of this, multiple management practices are used to ensure the continued health of their populations within Minnesota waters. In this study, the process of analyzing hematocrit levels was used to determine if the analysis of hematological parameters could be a useful tool in detecting differences in population health. To evaluate this, blood samples were acquired from age-0 and age-1 fish from two similar lakes and run through a hematocrit centrifuge to separate platelets from plasma to read the …

Editorial: Advances In Understanding Lateral Blue Carbon Export From Coastal Ecosystems, Kai Xiao, Nengwang Chen, Zhaohui Aleck Wang, Joseph James Tamborski, Damien Troy Maher, Xuan Yu

OES Faculty Publications

No abstract provided.

A Subsurface Eddy Associated With A Submarine Canyon Increases Availability And Delivery Of Simulated Antarctic Krill To Penguin Foraging Regions, K. Hudson, M. J. Oliver, J. Kohut, Michael S. Dinniman, John M. Klinck, M. A. Cimino, K. S. Bernard, H. Statscewich, W. Fraser

OES Faculty Publications

The distribution of marine zooplankton depends on both ocean currents and swimming behavior. Many zooplankton perform diel vertical migration (DVM) between the surface and subsurface, which can have different current regimes. If concentration mechanisms, such as fronts or eddies, are present in the subsurface, they may impact zooplankton near-surface distributions when they migrate to near-surface waters. A subsurface, retentive eddy within Palmer Deep Canyon (PDC), a submarine canyon along the West Antarctic Peninsula (WAP), retains diurnal vertically migrating zooplankton in previous model simulations. Here, we tested the hypothesis that the presence of the PDC and its associated subsurface eddy increases …

Temporal Stability Of Seagrass Extent, Leaf Area, And Carbon Storage In St. Joseph Bay, Florida: A Semi-Automated Remote Sensing Analysis, Marie Cindy Lebrasse, Blake A. Schaeffer, Megan M. Coffer, Peter J. Whitman, Richard C. Zimmerman, Victoria J. Hill, Kazi A. Islam, Jiang Li, Christopher L. Osburn

OES Faculty Publications

Seagrasses are globally recognized for their contribution to blue carbon sequestration. However, accurate quantification of their carbon storage capacity remains uncertain due, in part, to an incomplete inventory of global seagrass extent and assessment of its temporal variability. Furthermore, seagrasses are undergoing significant decline globally, which highlights the urgent need to develop change detection techniques applicable to both the scale of loss and the spatial complexity of coastal environments. This study applied a deep learning algorithm to a 30-year time series of Landsat 5 through 8 imagery to quantify seagrass extent, leaf area index (LAI), and belowground organic carbon (BGC) …

A Post-Pneumonia Epizootic Evaluation Of The Rapid City, South Dakota Bighorn Sheep Herd, Amanda N. Ensrud

Electronic Theses and Dissertations

Pneumonia is a major factor affecting populations of free-ranging bighorn sheep (Ovis canadensis) across western North America. Pneumonia can occur in large-scale epizootics, during which greater than half of the population typically dies. After these epizootics, surviving ewes continue to conceive and bear lambs. However, lamb recruitment may remain low due to periodic or annual pneumonia outbreaks causing high lamb mortality rates, sometimes greater than 90%. Our study focused on the Rapid City, South Dakota bighorn sheep (BHS) herd that has recorded pneumonia-induced population decline since 2009. The first objective was to improve lamb health and survival by identifying and …

Artificial Intelligence System For Automatic Imaging, Quantification, And Identification Of Arthropods In Leaf Litter And Pitfall Samples, Pierce Helton, Khoa Luu, Ashley Dowling

Inquiry: The University of Arkansas Undergraduate Research Journal

It is well known that arthropods are the most diverse and abundant eukaryotic organisms on the planet. Museum and research collections have huge insect accumulations from expeditions conducted over history that contain specimens of both temporal and spatial value, including hundreds of thousands of species. This biodiversity data is inaccessible to the research community, resulting in a vast amount of “dark data”. The primary objective of this study is to develop an artificial intelligence-driven system for specimen identification that greatly minimizes the time and expertise required to identify specimens in atypical environments. Successful development will have profound impacts on both …

Wetlandology: A Kid's Book About Wetlands, Grace Gaard, Ted Lagrange

Nebraska Game and Parks Commission: Publications

What is a Wetland? You might think that any land that is wet would be a wetland, right? But if the occurrence of water was the only thing that made a wetland a wetland, then deeper parts of oceans and rivers would be considered wetlands. And we know that is not true! So, what actually makes a wetland a wetland? Wetlands are defined by three things:

1. Soil

2. Plants

3. Hydrology

Wetlands are spread throughout Nebraska, but it is useful to identify some of the larger wetland complexes in the state. Wetlands can be found everywhere! All rivers and …

Guide To Nebraska's Wetlands And Their Conservation Needs, Third Edition, 2022, Ted Lagrange

Nebraska Game and Parks Commission: Publications

Wetlands: a source of great interest, and at times conflict. Wetlands represent different things to different people. To some people they may be considered shallow, muddy nuisances whereas to others they are considered to be wonderful, varied, and productive assets. This is because wetlands take on many roles as part of an elaborate and dynamic system. Understanding wetlands requires understanding the complex and varying roles they can play. To aid in this understanding, this guide defines wetlands, discusses their importance and dynamics, identifies threats and losses, describes conservation programs, and takes an in-depth look at Nebraska’s regional wetland complexes.

Nebraska’s …

Evaluating Avian Use Of Cover Crops In The Corn Belt, Megan Figura

Electronic Theses and Dissertations

The tallgrass prairie of North America has changed drastically since colonial settlement, with up to 99% of this region converted for agriculture and other land-uses. Concurrent with grassland conversion, grassland birds have experienced the most extreme, consistent, and widespread population declines of any avian guild. Agricultural lands in the U.S. Midwest were able to provide adequate habitat for several bird species until the 1950’s; however, altered and intensified management practices have degraded much of remaining suitable habitat and undermined ecosystem functions. Consequently, many grassland birds have been identified as Species of Greatest Conservation Need (SGCN) in many State Wildlife Action …

Zebra Mussel Length-Weight Relationships Across Various Substrate Types In Lake Bemidji, Mitch Kehne

Journal of Earth and Life Science

As of November 2021, zebra mussels were confirmed in 270 Minnesotan lakes with another 232 lakes listed as infested due to their connection or proximity to where zebra mussels have been found. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The goal of this study was to establish a length-weight relationship for the zebra mussel population in Lake Bemidji using shell length (SL) and wet weight (WW), as well as to assess substrate type and log transformed shell length as predictors of log transformed zebra …

Experimental Elucidation Of The Life Cycle Of Drepanocephalus Spathans (Digenea: Echinostomatidae) With Notes On The Morphological Plasticity Of D. Spathans In The United States, Neely R. Alberson, Thomas G. Rosser, Tommy King, Ethan T. Woodyard, Lester Khoo, Wes A. Baumgartner, Daviod J. Wise, Linda M. Pote, Fred L. Cunningham, Matt J. Griffin

United States Department of Agriculture Wildlife Services: Staff Publications

The echinostomatid Drepanocephalus spathans (syn. Drepanocephalus auritus) parasitizes the doublecrested cormorant Phalacrocorax auritus. In North America, the marsh rams-horn snail Planorbella trivolvis and ghost rams-horn snail Biomphalaria havanensis serve as snail intermediate hosts, both of which inhabit catfish aquaculture ponds in the southeastern United States. Studies have demonstrated D. spathans exposure can be lethal to juvenile channel catfish Ictalurus punctatus. Two studies were undertaken to elucidate the life cycle of D. spathans to establish a developmental time line. In both studies, D. spathans cercariae collected from naturally infected P. trivolvis individuals were used to infect channel catfish …

Scavenging Vs Hunting Affects Behavioral Traits Of An Opportunistic Carnivore, Mitchell A. Parsons, Andrew Garcia, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Background. Human-induced changes to ecosystems transform the availability of resources to predators, including altering prey populations and increasing access to anthropogenic foods. Opportunistic predators are likely to respond to altered food resources by changing the proportion of food they hunt versus scavenge. These shifts in foraging behavior will affect species interactions through multiple pathways, including by changing other aspects of predator behavior such as boldness, innovation, and social structure. Methods. To understand how foraging behavior impacts predator behavior, we conducted a controlled experiment to simulate hunting by introducing a prey model to captive coyotes (Canis latrans) and compared their behavior …

Influence Of Landscape Attributes On Virginia Opossum Density, David A. Bernasconi, Wesley C. Dixon, Matthew T. Hamilton, James L. Helton, Richard B. Chipman, Amy T. Gilbert, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

TheVirginia opossum (Didelphis virginiana), North America's only marsupial, has a range extending from southern Ontario, Canada, to the Yucatan Peninsula, Mexico, and from the Atlantic seaboard to the Pacific. Despite the Virginia opossum's taxonomic uniqueness in relation to other mammals in North America and rapidly expanding distribution, its ecology remains relatively understudied. Our poor understanding of the ecology of this important mesopredator is especially pronounced in the rural southeastern United States. Our goal was to estimate effects of habitat on opossum density within an extensive multiyear spatial capture‐recapture study. Additionally, we compared the results of this spatial capture‐recapture …

Multidisciplinary Engagement For Fencing Research Informs Efficacy And Rancher-To-Researcher Knowledge Exchange, Matthew Hyde, Stewart W. Breck, Alex Few, Jared Beaver, Joshua Schrecengost, Jim Stone, Cameron Krebs, Russell Talmo, Kari Eneas, Rae Nickerson, Kyran E. Kunkel, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Across much of the Western United States, recovery of large carnivore populations is creating new challenges for livestock producers. Reducing the risks of sharing the landscape with recovering wildlife populations is critical to private working lands, which play an vital role in securing future energy, water, food, and fiber for an ever-expanding human population. Fencing is an important mitigation practice that many ranchers, land managers, and conservationists implement to reduce carnivore-livestock conflict. While fencing strategies have been reviewed in the literature, research seldom incorporates knowledge from the people who utilize fencing the most (i.e., livestock producers). Incorporating producers and practitioners …

Targeted Browsing With Goats For Eastern Redcedar (Juniperus Virginiana L.) Control, Alanna M. Hartsfield

Electronic Theses and Dissertations

As eastern redcedar (ERC) (Juniperus virginiana L.) grassland encroachment progresses, all potential control methods should be explored in the interest of Great Plains grassland health and longevity. Targeted browsing with goats has been proven as an effective control method on some juniper species; however, little is known about its ability to control ERC. These studies intend to mend knowledge gaps of how targeted browsing with goats control ERC by causing tree death without chemicals or machinery. The first study is two 3x3 Latin squares comparing protein-supplemented diets. The second study is a randomized complete block design of five 0.224 ha …