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2022

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Articles 871 - 900 of 1056

Full-Text Articles in Ecology and Evolutionary Biology

Bottom-Up Effects Of Degradation Outweighs Stabilizing Potential Of Omnivores, Hannah Marie Moore Jan 2022

Bottom-Up Effects Of Degradation Outweighs Stabilizing Potential Of Omnivores, Hannah Marie Moore

Murray State Theses and Dissertations

Anthropogenic activities have led to degradation in streams throughout much of Western North America. In particular, cattle grazing has led to a loss of riparian vegetation resulting in higher water temperatures and an increase in nutrient runoff. The effects of degradation on food quality and quantity for aquatic consumers could have large implications for stream communities. Since omnivores feed at multiple trophic levels, they may be resilient to altered food webs, which may allow them to stabilize communities in degraded environments where resources have been reduced. To test the hypothesis that omnivores positively impact community stability in degraded conditions, I …


The Impacts Of Maple Syrup Production On The Herbaceous Layer In Appalachian Hardwood Forests, Logan Scott Ferguson Jan 2022

The Impacts Of Maple Syrup Production On The Herbaceous Layer In Appalachian Hardwood Forests, Logan Scott Ferguson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Vegetation data were collected from eight maple syrup farms (sugarbushes) and eight undeveloped maple-dominated sites to examine potential differences in understory plant communities due to disturbance effects. Understory plants were identified to the species level and percent cover of aboveground leaf-area for each species was estimated within 600 total quadrats. Overstory data and environmental data were collected to help determine if they had any effect on herbaceous-layer plant communities. Species richness, Shannon diversity, and Pielou’s evenness were calculated, with the analysis showing no significant differences between the site types. The absolute cover of plant functional groups was also compared between …


Reproductive Rates, Kitten Survival, And Den Site Selection Of Bobcats (Lynx Rufus) In The Black Hills, South Dakota, Erin E. Morrison Jan 2022

Reproductive Rates, Kitten Survival, And Den Site Selection Of Bobcats (Lynx Rufus) In The Black Hills, South Dakota, Erin E. Morrison

Graduate Theses, Dissertations, and Problem Reports (ETD)

The bobcat (Lynx rufus) is an important furbearer in South Dakota. However, management of bobcats can be difficult because of their elusive nature and lack of demographic information. In particular, managers lack information on abundance, survival, and reproductive rates necessary to ensure sustainable harvests and stable populations through time. Additionally, cause-specific mortality can provide insight into the factors influencing bobcat kitten survival rates, as well as reveal actions managers could take to improve survival. Bobcat resource selection can vary depending on spatial scale and it is important to understand how denning may result in different selection patterns at …


Potential Effects Of Amynthas Agrestis Invasion On Woody Understory Flora In The Cvnp, Christian Mammana Jan 2022

Potential Effects Of Amynthas Agrestis Invasion On Woody Understory Flora In The Cvnp, Christian Mammana

Williams Honors College, Honors Research Projects

Ohio forests are threatened by the invasive ecosystem engineer A. agrestis. A. agrestis invasion typically co-occurs with the ecosystem engineer, Odocoileus virginianus, where their impacts may synergize. To determine the direct effects of A. agrestis invasion, fenced plots across the Cuyahoga Valley National Park that excluded deer were utilized. The species richness, Shannon diversity and evenness of woody understory flora was measured in each plot. Mustard extraction was used to determine earthworm abundance. Correlations between abundance and measured variables were used to highlight potential invasion effects. Abundance and species richness was found to have a significant, positive correlation (p = …


Impacts And Dispersal Of Invasive Bivalves, Dreissena And Corbicula Spp., On Stream Benthic Communities, Darrin Scott Hunt Jan 2022

Impacts And Dispersal Of Invasive Bivalves, Dreissena And Corbicula Spp., On Stream Benthic Communities, Darrin Scott Hunt

Wayne State University Dissertations

Asian clams (Corbicula spp.), zebra and quagga mussels (Dreisenna spp.) have invaded and spread throughout North American surface waters. Corbicula and Dreisenna species bio foul aquatic systems, occupy benthic substrates and degrade environments through shell deposition. I explored how Dreissena and Corbicula invasions affect benthic fish and macroinvertebrate communities, and examine how their impacts differ between urban and rural systems, and temperate and tropical climates. Macroinvertebrate and fish communities were evaluated at sites with increasing shell densities in the Rouge, and Huron rivers (MI, USA) using the United States Environmental Protection Agency’s Rapid Bioassessment Protocols (RBP). Urban and rural macroinvertebrate …


Strong Inferences About Pain In Invertebrates Require Stronger Evidence, Edgar T. Walters Jan 2022

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 Jan 2022

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 Jan 2022

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 …


Large- And Small-Scale Climate Influences Spring Migration Departure Probability Of American White Pelicans, D. Tommy King, Guiming Wang, Fred L. Cunningham Jan 2022

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 Jan 2022

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 Jan 2022

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 Jan 2022

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 Jan 2022

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 …


Small Mammal Species Richness And Relative Abundance Across The Elevational Gradient And Microhabitats Of Pine Mountain, Eastern Kentucky, Sarah Elizabeth Baker Jan 2022

Small Mammal Species Richness And Relative Abundance Across The Elevational Gradient And Microhabitats Of Pine Mountain, Eastern Kentucky, Sarah Elizabeth Baker

Online Theses and Dissertations

Identifying microhabitat conditions influencing species abundance is critical to understanding distributions of species. Pine Mountain has forest types uncommon in Kentucky, but systematic small mammal surveys are dated. My objectives were: investigate variation in small mammal occurrence on Pine Mountain, and update small mammal records in the Eastern Kentucky University (EKU) mammal collection. I deployed pitfall traps, open from May - November 2021, at four state nature preserves (SNPs) on Pine Mountain. I measured microhabitat using 1 m2 quadrats at traps, then used redundancy analysis and generalized linear mixed (GLM) models to determine which conditions best explained variation in occurrence …


Phenotypic Plasticity Of Geographically Central And Peripheral Populations Of Jefferson Salamanders (Ambystoma Jeffersonianum) In Response To Simulated Climate Change, Aaron Devine Jan 2022

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 …


Comparison Of Spawning Habitat And Nest Density Between Buck Darter (Etheostoma Nebra) And Striped Darter (Etheostoma Virgatum) Populations In The Cumberland River Drainage, Kentucky, Jacob Charles Murphy Jan 2022

Comparison Of Spawning Habitat And Nest Density Between Buck Darter (Etheostoma Nebra) And Striped Darter (Etheostoma Virgatum) Populations In The Cumberland River Drainage, Kentucky, Jacob Charles Murphy

Online Theses and Dissertations

The Buck Darter (Etheostoma nebra) is an imperiled, small-stream species in the Cumberland River drainage in southern Kentucky. It was originally thought to be a population of the Striped Darter (E. virgatum) species and was prevalent throughout the Buck Creek system. It was separated from the Striped Darter and deemed a separate species in 2015; however, the population has declined dramatically. Presently, the species is found in three streams of the Flat Lick Creek system, two originally established populations in Big Spring Branch and Stewart Branch, and one newly introduced population, established in 2018, in an unnamed tributary. The decline …


Body Size And Habitat Shading Influence The Consumptive And Non-Consumptive Effects Of Wood Frog (Lithobates Sylvaticus) Tadpoles On Aquatic Invertebrate Communities, Brady Patrick Parlato Jan 2022

Body Size And Habitat Shading Influence The Consumptive And Non-Consumptive Effects Of Wood Frog (Lithobates Sylvaticus) Tadpoles On Aquatic Invertebrate Communities, Brady Patrick Parlato

Online Theses and Dissertations

Consumptive (direct) effects of predation have been well-studied in most aquatic systems, but non-consumptive (indirect) effects on prey have only recently received limited attention in some groups. As aquatic consumers, tadpoles have traditionally been considered strict herbivores, leaving their predatory impacts via consumptive and non-consumptive interactions on aquatic invertebrates largely unexplored. The objectives of this study were to quantify omnivory among wood frog (Lithobates sylvaticus) tadpoles, determine their consumptive and non-consumptive effects on invertebrate communities, and investigate whether such effects are mediated by habitat shading and tadpole body size. Lithobates sylvaticus tadpoles and egg masses were randomly sampled from 11 …


Genetic And Morphological Assessment Of Pigtoe Mussels (Unionidae: Pleurobemini: Fusconaia/Pleurobema Spp.) In Ozark Drainages, Logan Tyler Phelps Jan 2022

Genetic And Morphological Assessment Of Pigtoe Mussels (Unionidae: Pleurobemini: Fusconaia/Pleurobema Spp.) In Ozark Drainages, Logan Tyler Phelps

Online Theses and Dissertations

North America is home to nearly 300 species of native freshwater mussels. Many species within this group are in need of conservation efforts and for these efforts to be effective, species delimitations must be as accurate as possible. Intraspecific variation and interspecific convergence are sources of confusion within morphology-based taxonomy, particularly within the Pleurobemini. Molecular phylogenetic work has revealed multiple problems within currently accepted Pleurobemini classifications. Specifically, Fusconaia has been shown to harbor cryptic diversity within drainages of the Ozarks. Further, Pleurobema rubrum and P. sintoxia have been shown to be possible conspecifics despite have differing shell morphologies. This study …


Increased Signal Complexity Is Associated With Increased Mating Success, Noori Choi, Matt Adams, Kasey Fowler-Finn, Elise Knowlton, Malcolm Rosenthal, Aaron Rundus, Roger D. Santer, Dustin J. Wilgers, Eileen Hebets Jan 2022

Increased Signal Complexity Is Associated With Increased Mating Success, Noori Choi, Matt Adams, Kasey Fowler-Finn, Elise Knowlton, Malcolm Rosenthal, Aaron Rundus, Roger D. Santer, Dustin J. Wilgers, Eileen Hebets

Eileen Hebets Publications

The evolution of complex signals has often been explored by testing multiple functional hypotheses regarding how independent signal components provide selective benefits to offset the costs of their production. In the present study, we take a different approach by exploring the function of complexity per se. We test the hypothesis that increased vibratory signal complexity— based on both proportional and temporal patterning—provides selective benefits to courting male Schizocosa stridulans wolf spiders. In support of this hypothesis, all of our quantified metrics of vibratory signal complexity predicted the mating success of male S. stridulans. The rate of visual signalling, which is …


Description Of The Courtship And Copulation Behaviours Of The Wall Spider Oecobius Concinnus (Oecobiidae), Diego Solano-Brenes, Laura Segura-Hernández, Gilbert Barrantes Jan 2022

Description Of The Courtship And Copulation Behaviours Of The Wall Spider Oecobius Concinnus (Oecobiidae), Diego Solano-Brenes, Laura Segura-Hernández, Gilbert Barrantes

Eileen Hebets Publications

Courtship and copulation behaviours are yet scantily described in many spider families, and this lack of information limits our understanding of the evolution of such behaviours within and across families. Here, we provide a detailed description of both courtship and copulation behaviour for Oecobius concinnus Simon, 1893. A striking characteristic of the male courtship is the construction of a tubular web (mating web) in which most courtship and copulation occurs. This web likely functions to restrain the female in a reduced space and as a substrate for male pheromones. The courtship consists of a complex web of interactions between both …


An Examination Of Ethical Attitudes Towards Wild Pig (Sus Scrofa) Toxicants In The United States, Keith Carlisle, Erin E. Harper, Stephanie A. Shwiff Jan 2022

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 …


Frugivory And Seed Dispersal By Carnivorans, John P. Draper, Julie K. Young, Eugene W. Schupp, Noelle G. Beckman, Trisha B. Atwood Jan 2022

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 …


Aboveground Carbon Responses To Experimental And Natural Hurricane Impacts In A Subtropical Wet Forest In Puerto Rico, Hervé Chevalier, Nicholas V.L. Brokaw, Sheila E. Ward, Jess K. Zimmerman, Aaron B. Shiels, John Bithorn, Samuel Matta Carmona Jan 2022

Aboveground Carbon Responses To Experimental And Natural Hurricane Impacts In A Subtropical Wet Forest In Puerto Rico, Hervé Chevalier, Nicholas V.L. Brokaw, Sheila E. Ward, Jess K. Zimmerman, Aaron B. Shiels, John Bithorn, Samuel Matta Carmona

United States Department of Agriculture Wildlife Services: Staff Publications

Climate change and disturbance make it difficult to project long-term patterns of carbon sequestration in tropical forests, but large ecosystem experiments in these forests can inform predictions. The Canopy Trimming Experiment (CTE) manipulates two key components of hurricane disturbance, canopy openness and detritus deposition, in a tropical forest in Puerto Rico. We documented how the CTE and a real hurricane affected tree recruitment, biomass, and aboveground carbon storage over 15 years. In the CTE treatments, we trimmed branches, but we did not fell trees. We expected that during the 14-year period after initial canopy trimming, regrowth of branches and stems …


Behavioral States In Space And Time: Understanding Landscape Use By An Invasive Mammal, Steven M. Gray, John M. Humphreys, Robert A. Montgomery, Dwayne R. Etter, Kurt C. Vercauteren, Daniel B. Kramer, Gary J. Roloff Jan 2022

Behavioral States In Space And Time: Understanding Landscape Use By An Invasive Mammal, Steven M. Gray, John M. Humphreys, Robert A. Montgomery, Dwayne R. Etter, Kurt C. Vercauteren, Daniel B. Kramer, Gary J. Roloff

United States Department of Agriculture Wildlife Services: Staff Publications

Animal movement models can be used to understand species behavior and assist with implementation of management activities. We explored behavioral states of an invasive wild pig (Sus scrofa) population that recently colonized central Michigan, USA, 2014–2018. To quantify environmental factors related to wild pig movement ecology and spatio‐temporal landscape use, we predicted wild pig behavioral states relative to land cover type, landscape structure (i.e., edge and patch cohesion), and weather conditions. We used global positioning system (GPS)‐collars and monitored 8 wild pigs from 2014–2018. We fit local convex hulls and calculated movement metrics revealing 3 wild pig behavioral states (resting, …


Capture-Recapture Reveals Heterogeneity In Habitat-Specific Mongoose Densities And Spatiotemporal Variability In Trapping Success In St. Kitts, West Indies, Caroline C. Sauvé, Are R. Berentsen, Amy Gilbert, Anne Conan, Luis Cruz-Martinez, Patrick A. Leighton Jan 2022

Capture-Recapture Reveals Heterogeneity In Habitat-Specific Mongoose Densities And Spatiotemporal Variability In Trapping Success In St. Kitts, West Indies, Caroline C. Sauvé, Are R. Berentsen, Amy Gilbert, Anne Conan, Luis Cruz-Martinez, Patrick A. Leighton

United States Department of Agriculture Wildlife Services: Staff Publications

The small Indian mongoose (Urva auropunctata) is a non-native invasive species across the Caribbean and a rabies reservoir on at least four islands in the region. Although previous studies reported mongoose density estimates in their non-native range, the variability in trapping designs, study seasonality, and analytical methods among studies precludes direct comparisons. This study is the first to report mongoose densities for the island of St. Kitts, West Indies. Our objective was to quantify mongoose densities across four habitats characteristic for the island. High capture and recapture rates in this study resulted in detailed estimates of spatial heterogeneity …


Dammed Water Quality—Longitudinal Stream Responses Below Beaver Ponds In The Umpqua River Basin, Oregon, John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor Jan 2022

Dammed Water Quality—Longitudinal Stream Responses Below Beaver Ponds In The Umpqua River Basin, Oregon, John R. Stevenson, Jason B. Dunham, Steven M. Wondzell, Jimmy Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Beaver-related restoration (BRR) has gained popularity as a means of improving stream ecosystems, but the effects are not fully understood. Studies of dissolved oxygen (DO) and water temperature, key water quality metrics for salmonids, have demonstrated improved conditions in some cases, but warming and decreased DO have been more commonly reported in meta-analyses. These results point to the contingencies that can influence outcomes from BRR. We examined water quality related to beaver ponds in a diverse coastal watershed (Umpqua River Basin, OR, USA). We monitored water temperature 0–400m above and below beaver ponds and at pond surfaces and bottoms across …


Invasive Rodent Responses To Experimental And Natural Hurricanes With Implications For Global Climate Change, Aaron B. Shiels, Gabriela E. Ramírez De Arellano, Laura Shiels Jan 2022

Invasive Rodent Responses To Experimental And Natural Hurricanes With Implications For Global Climate Change, Aaron B. Shiels, Gabriela E. Ramírez De Arellano, Laura Shiels

United States Department of Agriculture Wildlife Services: Staff Publications

Hurricanes cause dramatic changes to forests by opening the canopy and depositing debris onto the forest floor. How invasive rodent populations respond to hurricanes is not well understood, but shifts in rodent abundance and foraging may result from scarce fruit and seed resources that follow hurricanes. We conducted studies in a wet tropical forest in Puerto Rico to better understand how experimental (canopy trimming experiment) and natural (Hurricane Maria) hurricane effects alter populations of invasive rodents (Rattus rattus [rats] and Mus musculus [mice]) and their foraging behaviors. To monitor rodent populations, we used tracking tunnels (inked and baited cards …


Improving Efficiency Of Prairie Dog Surveys By Using A Small Copter Drone, Aaron B. Shiels, J. W. Fischer, Danika Spock, Meagan Allira Jan 2022

Improving Efficiency Of Prairie Dog Surveys By Using A Small Copter Drone, Aaron B. Shiels, J. W. Fischer, Danika Spock, Meagan Allira

United States Department of Agriculture Wildlife Services: Staff Publications

Prairie dogs are an accessible and enjoyed wildlife species in Colorado that require occasional surveys because populations can change abruptly due to plague outbreaks or human-induced control. We evaluated the use of small copter drones at four prairie dog colonies on Open Space and Mountain Parks lands, City of Boulder, to determine if this methodology improves efficiency over ground-based survey methods. We counted prairie dogs and burrows using two types of drones (DJI Matric 210 and Autel Evo II) at altitudes 100', 150', and 400' (burrows only). We recorded video and merged still images into orthomosaics prior to having USDA …


Changes In Plant Community Composition, Structure, And Function In Response To Permafrost Thaw, Katherine Standen Jan 2022

Changes In Plant Community Composition, Structure, And Function In Response To Permafrost Thaw, Katherine Standen

Theses and Dissertations (Comprehensive)

Air temperature is increasing at three or more times the global average in high latitudes, causing widespread permafrost thaw across the boreal biome. Since the boreal biome stores 30-40% of global terrestrial carbon (C), of which about 30-45% is found in permafrost soils, this temperature increase could cause a large efflux of C to the atmosphere. Climate warming and permafrost thaw are also expected to alter plant community composition and productivity and, given the link between plant functional traits and ecosystem C fluxes, may alter overall ecosystem function. Across the boreal biome of western Canada, we know surprisingly little about …


Arctic Stream Characteristics And Diet Analysis Choice Impact Condition And Diet Estimates Of Ninespine Stickleback (Pungitius Pungitius), Adam Kuhrt Jan 2022

Arctic Stream Characteristics And Diet Analysis Choice Impact Condition And Diet Estimates Of Ninespine Stickleback (Pungitius Pungitius), Adam Kuhrt

Theses and Dissertations (Comprehensive)

Ninespine stickleback (Pungitius pungitius) are ubiquitous in circumpolar freshwaters, but their ecological role is not well understood. Little research has been conducted on the influence of environmental variables on ninespine stickleback in stream environments, and while they are understood to be generalist feeders, their diet in stream environments is equally understudied. Determining diet is difficult due to biases inherent in all standard diet analysis methods. Morphological gut-content analysis (M-GCA), DNA metabarcoding of gut contents (D-GCA), and stable isotope analysis (SIA) are currently three of the most frequently conducted diet analyses; and while combinations of these methods are commonly …