Terrestrial and Aquatic Ecology Commons^™

Factors Influencing Mortality Of Stocked Rainbow Trout In Black Hills Reservoirs, Charles A. Mordhorst

Electronic Theses and Dissertations

Because return to angler is an important outcome of put-and-take fisheries, understanding mortality of stocked Rainbow Trout is fundamental to managing these fisheries. Harvest rates of stocked Rainbow Trout Oncorhynchus mykiss in the Black Hills of South Dakota are believed to be below management objectives. Rainbow Trout not harvested by anglers are assumed to be lost to various sources of mortality, raising concerns about the cost of the Rainbow Trout stocking program relative to the benefit provided to anglers. (Simpson 2008). This study evaluated the factors influencing mortality of Rainbow Trout stocked into Black Hills reservoirs. We assessed the effects …

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 …

Changes In The Zooplankton Community In Barren River Lake (South Central Ky) Between 2008 And 2020, Laurel Philpott

Mahurin Honors College Capstone Experience/Thesis Projects

Zooplankton are small aquatic animals that serve an important role in transferring energy from phytoplankton to higher trophic levels. The zooplankton community composition in Barren River Lake from 2008 and 2020 was compared. A field study was conducted to not only describe the seasonal population dynamics of zooplankton in Barren River Lake, but also to determine if an invasive zooplankton, Daphnia lumholtzi, was present. While D. lumholtzi was found throughout Barren River Lake in 2008, it was absent from both resampled sites in 2019 and 2020. This, along with erratic patterns of emergence in several other zooplankton species, indicates …

Characterizing And Predicting Beaver Pond Habitat In Kittitas County, Washington, Kylie Vroman

All Master's Theses

North American Beavers (Castor canadensis) are important ecosystem engineers in the Pacific Northwest (PNW), as they provide ecosystem services and create habitats that benefit aquatic species, watersheds, and riparian vegetation. Even though the species has been coined a “nuisance” in some settings, it is common for environmental agencies to capture beavers and relocate them to areas where it is less likely for them to cause damage. This study geospatially modeled the Kittitas County landscape to identify areas of suitable habitat. Nine existing beaver ponds in Kittitas County were investigated; three of which were prior relocation sites that had failed, three …

Sentience In Decapod Crustaceans: A General Framework And Review Of The Evidence, Andrew Crump, Heather Browning, Alex Schnell, Charlotte Burn, Jonathan Birch

Animal Sentience

We outline a framework for evaluating scientific evidence of sentience, focusing on pain experience. It includes eight neural and cognitive-behavioural criteria, with confidence levels for each criterion reflecting the reliability and quality of the evidence. We outline the rationale for each criterion and apply our framework to a controversial sentience candidate: decapod crustaceans. We have either high or very high confidence that true crabs (infraorder Brachyura) satisfy five criteria, amounting to strong evidence of sentience. Moreover, we have high confidence that both anomuran crabs (infraorder Anomura) and astacid lobsters/crayfish (infraorder Astacidea) meet three criteria—substantial evidence of sentience. The case is, …

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 …

Changes In The Minnesota Northern Pike Population Over The Past Thirty Years, Joey Severin

Journal of Earth and Life Science

Northern pike Esox lucius are one of the most popular game fish in Minnesota. Many anglers have noticed that northern pike seemed to decrease in size throughout much of this state. Catch per unit of effort (CPUE) drives average weight for northern pike; within lakes, as CPUE goes up average weight decreases. Decreases in size has led the Minnesota Department of Natural Resources (MNDNR) to implement new regulations on northern pike. The MNDNR noticed that not all the state has this same problem with Northern Pike, and has broken down the state into three zones, with different protected slots and …

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 …

Legal Recognition Of Animal Sentience: The Case For Cautious Optimism, Jane Kotzmann

Animal Sentience

Rowan et al.’s target article provides a valuable indication of the work that was required to reach the point where animals are recognised as sentient in various laws. To ensure this work was not in vain, the language of sentience needs to be used as a moral currency to demand further cultural change involving greater human respect for animals.

Effects Of Environmental Warming On Clarias Gariepinus Growth And Physiology, Dean Cahill

Capstone Showcase

Fresh water makes up about 0.8% of the Earth’s surface and is home to six percent of its species. Environmental warming is projected to have a significant effect on freshwater systems as the century progresses. They are susceptible to irreversible damage because fresh water availability and temperature is dependent of climate. The Clarias gariepinus, or the African Catfish, is popular among aquaculture in Africa and Asia because of its rapid growth, quick reproduction, and hardiness. The goal of my thesis was to examine the effect of environmental warming and elevated temperatures on the growth and physiology of Clarias gariepinus populations …

Sentience Politics : A Fishy Perspective, Culum Brown

Animal Sentience

The plight of fishes has almost certainly got worse since Bentham (1789) coined the phrase “The question is not Can they reason? nor, Can they talk? but Can they suffer?” Despite the fact that fishes are increasingly recognised as sentient animals worthy of protection under animal welfare legislation in many countries around the world, fishing practices are almost universally exempt activities. The human population continues to grow, and, surprisingly, per capita intake of fish is still increasing (FAO 2020). The source of this fish is not wild stocks (catches of which have remained more or less stagnant for …

All Living Organisms Are Sentient, Arthur S. Reber, Frantisek Baluska, William B. Miller Jr.

Animal Sentience

We argue that all living organisms, from the simplest unicellular prokaryotes to Homo sapiens, have valenced experiences—feelings as states of preference—and are capable of cognitive representations. Bacteria can learn, form stable memories, and communicate, hence solve problems. Rowan et al.'s statement that "Subjective feelings are just that — subjective — and are available only to the animal (or human) experiencing them" is true but irrelevant. When we see a fish flopping about in the bottom of a boat we immediately recognize suffering without having a glimpse of the nature of piscine distress. Some controlled anthropomorphism can go a …

The Science Of Animal Sentience And The Politics Of Animal Welfare Should Be Kept Separate, Marian Stamp Dawkins

Animal Sentience

Although linked historically by Rowan et al., the scientific study of animal sentience and political campaigns to improve animal welfare should be kept separate, for at least two reasons. First, the separation makes it clear that standards of evidence acceptable for ethical or political decisions on animal welfare can be lower than those required for a rigorously scientific approach to animal sentience. Second, it helps to avoid confirmatory bias in the form of giving undue weight to results that are in line with pre-conceived ideas and political views.

Strong Inferences About Pain In Invertebrates Require Stronger Evidence, Edgar T. Walters

Animal Sentience

Evidence for sentience in animals distantly related to humans is often sought in observations of behavioral and neural responses to noxious stimuli that would be painful in humans. Most proposed criteria for painful sentience in “lower” animals such as decapod crustaceans have no necessary links to the affective (“suffering”) component of pain. The best evidence for painful affect in animals is learned aversion to stimuli associated with noxious experience, and conditioned preference for contexts associated with relief from aversive consequences of noxious experience, as expressed in voluntary behavior. Such evidence is currently lacking for any invertebrate except octopus.

Longevity Of An Immunocontraceptive Vaccine Effect On Fecundity In Rats, Rebecca Pinkham, Douglas C. Eckery, Richard E. Mauldin, M. Gomm, F. Hill, F. Vial, G. Massei

United States Department of Agriculture Wildlife Services: Staff Publications

Increases in human-wildlife conflicts alongside cultural shifts against lethal control methods are driving the need for alternative wildlife management tools such as fertility control. Contraceptive formulations suitable for oral delivery would permit broader remote application in wildlife species.

This study evaluated the contraceptive effect and immune response to two novel injectable immunocontraceptive formulations targeting the Gonadotropin Releasing Hormone (GnRH): MAF-IMX294 and MAF-IMX294P conjugates, both identified as having potential as oral contraceptives. The study also explored whether in multiparous species immunocontraceptives may either totally prevent reproduction or also affect litter size.

Female rats, chosen as a model species, were given three …

Rapid Changes In Public Perception Toward A Conservation Initiative, Rebecca Niemiec, Richard E.W. Berl, Mireille Gonzalez, Tara L. Teel, Jonathan Salerno, Stewart Breck, Cassiopeia Camara, Matthew Collins, Courtney Scholtz, Dana Hoag, Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

Rapid, widespread changes in public perceptions and behaviors have the potential to influence conservation outcomes. However, few studies have documented whether and how such shifts occur throughout the span of a conservation initiative. We examined the 2020 ballot initiative to reintroduce wolves into Colorado, which passed with less support than prior surveys had estimated. We conducted a postelection survey of Colorado residents using the same methods as our preelection survey to compare responses between surveys and to official election results. Reported voting in favor of wolf reintroduction in the postelection survey decreased in comparison to voting intentions shared in the …

A Model For Leveraging Animal Movement To Understand Spatio-Temporal Disease Dynamics, Mark Q. Wilber, Anni Yang, Raoul Boughton, Kezia R. Manlove, Ryan S. Miller, Kim M. Pepin, George Wittemyer

United States Department of Agriculture Wildlife Services: Staff Publications

The ongoing explosion of fine-resolution movement data in animal systems provides a unique opportunity to empirically quantify spatial, temporal and individual variation in transmission risk and improve our ability to forecast disease outbreaks. However, we lack a generalizable model that can leverage movement data to quantify transmission risk and how it affects pathogen invasion and persistence on heterogeneous landscapes. We developed a flexible model ‘Movement-driven modelling of spatio-temporal infection risk’ (MoveSTIR) that leverages diverse data on animal movement to derive metrics of direct and indirect contact by decomposing transmission into constituent processes of contact formation and duration and pathogen deposition …

Large- And Small-Scale Climate Influences Spring Migration Departure Probability Of American White Pelicans, D. Tommy King, Guiming Wang, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Endogenous (e.g., age and sex) and exogenous (e.g., climate and resource availability) factors influence avian migration phenology. However, little is known regarding the migration ecology of birds at the non-breeding grounds, including the American white pelican (Pelecanus erythrorhynchos). We used Global Positioning System transmitters to track the movements and migration of 51 pelicans from 2002 to 2012. We used the Kaplan–Meier model to estimate pelican spring migration probabilities to quantify partial migration with 94 spring migration events and used the Cox proportional hazards model to evaluate the effects of the North Atlantic Oscillation index (NAOI), Southern Oscillation Index (SOI), and …

Adaptive Risk-Based Targeted Surveillance For Foreign Animal Diseases At The Wildlife-Livestock Interface, Ryan S. Miller, Sarah N. Bevins, Gericke Cook, Ross Free, Kim M. Pepin, Thomas Gidlewski, Vienna Brown

United States Department of Agriculture Wildlife Services: Staff Publications

Animal disease surveillance is an important component of the national veterinary infrastructure to protect animal agriculture and facilitates identification of foreign animal disease (FAD) introduction. Once introduced, pathogens shared among domestic and wild animals are especially challenging to manage due to the complex ecology of spillover and spillback. Thus, early identification of FAD in wildlife is critical to minimize outbreak severity and potential impacts on animal agriculture as well as potential impacts on wildlife and biodiversity. As a result, national surveillance and monitoring programs that include wildlife are becoming increasingly common. Designing surveillance systems in wildlife or, more importantly, at …

Evidence For Irruptive Fluctuation In Axis Deer Of Hawai‘I, Steven C. Hess, Jonathan Sprague, Jacob Muise

United States Department of Agriculture Wildlife Services: Staff Publications

Axis deer on the Hawaiian Islands of Maui, Lāna‘i, and Moloka‘i simultaneously experienced one of the most dramatic population crashes on record in 2020-2021, which coincided with extended drought conditions and prompted an emergency declaration for these islands. This phenomenon has been anecdotally documented during previous drought events in 2011-2012, but never formally studied. Newspaper articles document abundant deer becoming a nuisance to agriculture and natural resources, and then experiencing high mortality during droughts. This phenomenon fits Caughley’s (1970) operational definition of eruptive (sic) fluctuation “…as an increase in numbers over at least two generations, followed by a marked decline.” …

Cultivation Of Industrial Hemp On And Near Airports: Implications For Wildlife Use And Risk To Aviation Safety, Bradley F. Blackwell, Page E. Klug, Lee A. Humberg, Zachary T. Brym, Bryan M. Kluever, Jenna Edwards

United States Department of Agriculture Wildlife Services: Staff Publications

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and …

Industrial Hemp As A Resource For Birds In Agroecosystems: Human-Wildlife Conflict Or Conservation Opportunity?, Emily A. Kotten, Iona Hennessy, Bryan M. Kluever, Bradley F. Blackwell, Lee A. Humberg, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and …

The Reality And Prevalence Of Animal Sentience, Antonio Damasio

Animal Sentience

Rowan et al use findings from neurobiology, clinical neurology, and general biology to argue for the extensive presence of sentience in animals, but they are wisely cautious concerning when in the phylogenetic scale that emergence occurred.

An Examination Of Ethical Attitudes Towards Wild Pig (Sus Scrofa) Toxicants In The United States, Keith Carlisle, Erin E. Harper, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

This research aims to understand ethical attitudes of the U.S. public towards the use of a toxicant to control wild pigs (Sus scrofa), a destructive invasive species whose population growth is proving difficult to control through conventional management methods. Using a nationwide self-administered survey with 2,186 completed and returned questionnaires, we found that among six different lethal control methods, toxicant usage was the only method that a majority of respondents (51%) found to be unethical, with no significant differences between rural and urban respondents or between respondents from counties with wild pigs and counties where the species is absent. The …

Relationship Between Reproductive Hormones And Migration Distance In A Polygynous Songbird, The Red‑Winged Blackbird (Agelaius Phoeniceus), Michelle A. Eshleman, Page E. Klug, Esther Morales‑Vega, Björn Wissel, Timothy J. Grelves

United States Department of Agriculture Wildlife Services: Staff Publications

Many bird species migrate to southern overwintering locations to avoid harsh conditions at their breeding grounds, but at the cost of an energetically demanding migration that may delay their spring reproductive development. Previous work on the relationship between migration distance and reproductive readiness has primarily focused on early season baseline testosterone in both males and females. However, for females, testosterone alone may not be the appropriate measurement of reproductive development. Estradiol, a metabolite of testosterone that is essential for breeding behaviors and reproduction, should also be measured. Furthermore, baseline testosterone varies throughout the day and may change due to social …

A Systematic Map Of Human-Carnivore Coexistence, Cassandre C. Venumière-Lefebvre, Stewart W. Breck, Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

Carnivore populations globally have largely declined, and coexistence, where humans and carnivores share landscapes, plays a crucial role in carnivore conservation. However, the term “coexistence” is often used in scientific and popular literature without being clearly defined. Herein, we provide a global perspective on what coexistence is and how it is studied. We conducted a systematic map of 366 articles published between 1987 and 2020 to characterize human-carnivore coexistence literature according to coexistence definitions, temporal trends, geographic and taxonomic focus, and four thematic aspects of coexistence: carnivore ecology, human endeavors, social conflict and human-carnivore conflict. We used chi-squared tests and …

Frugivory And Seed Dispersal By Carnivorans, John P. Draper, Julie K. Young, Eugene W. Schupp, Noelle G. Beckman, Trisha B. Atwood

United States Department of Agriculture Wildlife Services: Staff Publications

Seed dispersal is critical to the ecological performance of sexually reproducing plant species and the communities that they form. The Mammalian order Carnivora provide valuable and effective seed dispersal services but tend to be overlooked in much of the seed dispersal literature. Here we review the literature on the role of Carnivorans in seed dispersal, with a literature search in the Scopus reference database. Overall, we found that Carnivorans are prolific seed dispersers. Carnivorans’ diverse and plastic diets allow them to consume large volumes of over a hundred families of fruit and disperse large quantities of seeds across landscapes. Gut …