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Articles 181 - 210 of 342

Full-Text Articles in Ecology and Evolutionary Biology

Distribution, Density, Movement, And Support For Management Of Mountain Sucker, Pantosteus Jordani, In The Black Hills Of South Dakota, Seth J. Fopma Jan 2020

Distribution, Density, Movement, And Support For Management Of Mountain Sucker, Pantosteus Jordani, In The Black Hills Of South Dakota, Seth J. Fopma

Electronic Theses and Dissertations

Mountain Sucker, Pantosteus jordani, is a cold-water species native to the Intermountain West. Fringe populations of Mountain Sucker have experienced declines in recent decades. The population of Mountain Sucker found in the Black Hills of South Dakota represents the eastern fringe of the species’ native range. Recognized as both an indicator of biologic health and as a species of greatest conservation need in South Dakota, recent studies have suggested significant declines in both distribution and abundance. Despite the recent study of Mountain Sucker in the region, increased understanding of Mountain Sucker ecology is needed to effectively manage for the conservation …


Influence Of Mink Predation On Brown Trout Survival And Size-Structure In Rapid Creek, South Dakota, Austin Galinat Jan 2020

Influence Of Mink Predation On Brown Trout Survival And Size-Structure In Rapid Creek, South Dakota, Austin Galinat

Electronic Theses and Dissertations

I compared movement, home range, habitat selection, and mortality among radio-tagged Brown Trout (Salmo trutta) at an American Mink (Neovison vison)-removal site, improved habitat site, and an undisturbed stream site in Rapid Creek, South Dakota. I observed high, post-surgery (> 26 days) survival rate (90%) of radio tagged Brown Trout. Average gross movement of Brown Trout was greater at the improved habitat site (127 m) compared to the mink removal (31 m) site, while average home range size (i.e., stream distance) among all three sites was not significantly different indicating strong site fidelity (125 to 200 m). Brown Trout movements …


Examining Biodiversity Metrics And The Utility Of Dna Barcoding In The Northern Great Plains, Sarah Herzog Jan 2020

Examining Biodiversity Metrics And The Utility Of Dna Barcoding In The Northern Great Plains, Sarah Herzog

Electronic Theses and Dissertations

Due to heavy threats to remaining global floral and faunal diversity, it is imperative we can identify species and quantify ecosystem health to find best practices for land management and conservation. The tallgrass prairies of the Northern Great Plains are one example of a heavily imperiled ecosystem. The tallgrass prairies have been reduced to less one percent of their historical extent and are facing continued loss. Genetic approaches and evolutionary theory offer insights for identifying species and assessing how biodiversity metrics may correlate with ecosystem processes. My two projects aim to address two facets imperative to conservation in the tallgrass …


Higher Temperatures Have Contrasting Effects On Different Components Of Forage Quality For Caribou In Northern Alaska, Heidi Becker Jan 2020

Higher Temperatures Have Contrasting Effects On Different Components Of Forage Quality For Caribou In Northern Alaska, Heidi Becker

Electronic Theses and Dissertations

Rising temperatures in the Arctic may affect vegetation, which in turn can affect herbivores, such as caribou, that rely on these plants for forage. Several plant traits contribute to forage quality, including digestibility, nitrogen content, and antiherbivory secondary compounds, but the effect of temperature on these traits individually and combined is unclear. I conducted a three-component study on the effect of higher temperatures on the forage quality of graminoids, deciduous shrubs, and evergreen dwarf shrubs on the North Slope of Alaska. The components included: 1) short and long-term experimental warming, 2) natural temperature variation between south and north-facing slopes, and …


Evaluation Of Fall-Seeded Cover Crops For Grassland Nesting Waterfowl In Eastern South Dakota, Charles W. Gallman Iii Jan 2020

Evaluation Of Fall-Seeded Cover Crops For Grassland Nesting Waterfowl In Eastern South Dakota, Charles W. Gallman Iii

Electronic Theses and Dissertations

The Prairie Pothole Region is the primary breeding ground for many species of North American waterfowl. This landscape was historically dominated by mixed and tallgrass prairies interspersed with wetlands, but >70% of native grassland area has been lost due to widespread conversion to croplands, which may threaten waterfowl production. Cover cropping is a re-emerging farming technique that may provide suitable nesting cover for grassland nesting waterfowl on active farmlands. My research objectives were to evaluate the utility of fall-seeded cover crops to breeding waterfowl compared to perennial cover, determine if cover crops in rotation with row crops can successfully support …


The Effect Of Neonicotinoid Clothianidin On Ring-Necked Pheasant Survival And Reproduction, Michael Sundall Jan 2020

The Effect Of Neonicotinoid Clothianidin On Ring-Necked Pheasant Survival And Reproduction, Michael Sundall

Electronic Theses and Dissertations

Ring-necked pheasants (Phasianus colchicus) are economically important to the state of South Dakota bringing in over one hundred million dollars in revenue each season. The population is known to fluctuate temporally for many reasons, often weather related. Unfortunately, no research has been conducted involving ring-necked pheasants that evaluated the impact or interaction of neonicotinoids on the species. The objective of our study was to gain an understanding of how the neonicotinoid, Clothianidin, affects survival and breeding in pheasants. Our first experiment was to determine if there was a selection bias for seeds treated with neonicotinoids. In this experiment, eight ring-necked …


Epidemiological Investigations Of Bighorn Sheep Respiratory Disease And Implications For Management, Brandi L. Felts Jan 2020

Epidemiological Investigations Of Bighorn Sheep Respiratory Disease And Implications For Management, Brandi L. Felts

Electronic Theses and Dissertations

Infectious respiratory disease has long been identified as the cause of bighorn sheep (Ovis canadensis) historical declines and extirpations, and Mycoplasma ovipneumoniae (Movi) is the primary pathogen inducing disease and mortality. Population-level effects of pneumonia events range from mild to extirpation. Variable individual response to pathogen exposure emerges from dynamic interactions between competing evolutionary processes within the host and pathogen. Understanding impacts of this evolutionary warfare is essential to assessing long-term impacts of pathogen invasion and developing appropriate countermeasures to protect population health. Freeranging populations are faced with spillover infections from domestic sheep and goats as well as …


Winter Patch Grazing, Patch Burn Grazing, And Bird Communities In Western South Dakota, Jennifer Lutze Jan 2020

Winter Patch Grazing, Patch Burn Grazing, And Bird Communities In Western South Dakota, Jennifer Lutze

Electronic Theses and Dissertations

Ground nesting bird species are on a considerable decline and research efforts are being made to increase these populations throughout the Great Plains. Ground nesting bird communities found in the Northern Great Plains are driven greatly by varying amounts of cover and area size. Past research implemented patch-burn grazing to increase structural heterogeneity and to increase grassland bird habitat in the tallgrass prairie. While bird populations were very responsive to this management in the Northern Great Plains fire management is viewed negatively, especially for Midwest cattle ranchers. We implemented research to determine if winter-patch grazing on mixed grass prairie could …


Visual Opsin Diversity In Anurans, Leah Perez Aug 2019

Visual Opsin Diversity In Anurans, Leah Perez

Electronic Theses and Dissertations

Among major vertebrate groups, anurans are understudied with regards to their visual systems and how they function. This study sampled North American anurans representing diverse evolutionary and life histories and which likely possess visual systems adapted to meet different ecological needs. Using standard molecular techniques, sequences were obtained for four opsins—the protein component of visual pigments—expressed in anuran retinas. Amino acid sequences of the genes RH1, LWS, SWS1, and SWS2 were compared across taxa to identify variable sites, as such variation can shift the spectral sensitivity of visual pigments and thus alter dim-light and color vision. Some of the amino …


The Effects Of Constructed Wetlands On Metal Solubilization And Bioavailability In Passive Mine Remediation, Elizabeth Cochran May 2019

The Effects Of Constructed Wetlands On Metal Solubilization And Bioavailability In Passive Mine Remediation, Elizabeth Cochran

Electronic Theses and Dissertations

The legacy of coal mining in Appalachia has left many watersheds impacted by abandoned mine drainage. The drainage degrades streams, groundwater and habitats with acidity and toxic heavy metals. The Lowber Passive Remediation System has been in operation since 2004 to remediate high amounts of dissolved Fe, SO4, Al, and Mn. The site consists of six settling ponds and an extensive wetlands at the finish. This study investigated the resolubilization of Fe and Mn in the wetlands and the role of bacteria in resolubilization. During three seasons, field measurements of water quality and lab analysis of Fe, Mn, …


Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates May 2019

Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates

Electronic Theses and Dissertations

Increases in mean surface air temperature under climate-change predictions are expected to affect microbial activity, as well as carbon dynamics in aquatic ecosystems. I explored responses of litter-associated decomposers along temperature ranges typical of temperate streams in laboratory microcosms simulating stream conditions. The objectives of this study were to determine (1) whether the effects of temperature on stream leaf-associated microorganisms can be explained by the Metabolic Theory of Ecology (MTE); (2) if the effects of temperature are the same across temperatures commonly found in temperate streams; and (3) if there are differences in the magnitude of responses to temperature among …


Microplastics In The Digestive System Of The Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) In Winyah Bay, Sc, Elise Virginia Pullen May 2019

Microplastics In The Digestive System Of The Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) In Winyah Bay, Sc, Elise Virginia Pullen

Electronic Theses and Dissertations

The digestive tracts and livers of adult male Atlantic sharpnose sharks (N=16), Rhizoprionodon terraenovae, from Winyah Bay, South Carolina were examined for ingested microplastics. R. terraenovae is a small, locally abundant, coastal mesopredatory elasmobranch belonging to the family Carcharhinidae. Microfibers comprised the largest categories of plastics (94% of the total), and were found in 100% of sharks examined. The number of micro- and other plastics ranged from 34 to 75 per individual and totaled 927. The majority of plastics (40%) were blue in coloration, and 55% were <1 mm in length. Microplastics were observed on both the interior and exterior of the organs examined, and three microfibers were embedded within the stomach lining, an observation not previously reported in marine vertebrates and one which represents a potential pathway for the translocation of ingested microplastics.


Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner May 2019

Differentiating Black Bears (Ursus Americanus) And Brown Bears (U. Arctos) Using Linear Tooth Measurements And Identification Of Ursids From Oregon Caves National Monument, Emily Bogner

Electronic Theses and Dissertations

North American black bears and brown bears can be difficult to distinguish in the fossil record due to similar dental and skeletal morphologies. Challenges identifying ursid material from Oregon Caves National Monument (ORCA) called for an accurate tool to distinguish the species. This study utilized a large database of lower tooth lengths and ratios in an attempt to differentiate black and brown bears in North America. Further, this project examined how these linear measurements differ geographically. Analysis of variance (ANOVA) found significant differences between black and brown bears from across North America for every variable studied. Stepwise discriminant analyses (DA) …


Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap May 2019

Ecometric Estimation Of Present And Past Climate Of North America Using Crown Heights Of Rodents And Lagomorphs: With Application To The Middle Miocene Climatic Optimum, Julia Schap

Electronic Theses and Dissertations

Continental scale studies on ungulate crown heights in relation to climate and habitat changes have revealed a correlation between increasing hypsodonty and a shift to more arid environments. Small mammals have been shown to adapt to changing habitats millions of years earlier than larger mammals. In this study I examined fossil localities throughout the last 37 Ma across North America. Diversity of rodents and lagomorphs were analyzed through this time period, with examination of community structure characterized by relative percentages of taxa with different crown heights. Overall, a decrease in precipitation and temperature was found across North America from 37 …


Winter Snow Depth In Arctic Alaska Results In Complex Changes In Caribou Forage Quality, Jessica C. Richert Jan 2019

Winter Snow Depth In Arctic Alaska Results In Complex Changes In Caribou Forage Quality, Jessica C. Richert

Electronic Theses and Dissertations

Caribou (Rangifer tarandus) rely on the short growing season for much of their annual nutrition, making them susceptible to even small changes in forage quantity and quality. Body condition in the summer and fall is linked to winter survival rates and fecundity in cows, critical factors in the robustness of caribou populations. Due to a warmer, wetter climate, snowfall is predicted to increase over Alaska’s North Slope in the next several decades. Deeper snow results in higher soil temperatures, allowing microbial mineralization of nitrogen to continue throughout the winter and increasing the availability of nitrogen for plants in spring and …


Maximizing Ecosystem Services Provided To The New Oil Crop Brassica Carinata Through Landscape And Arthropod Diversity, Shane Stiles Jan 2019

Maximizing Ecosystem Services Provided To The New Oil Crop Brassica Carinata Through Landscape And Arthropod Diversity, Shane Stiles

Electronic Theses and Dissertations

Prairies, once spanning the Upper Midwest, have now largely been replaced by agriculture. The lack of resources available to pollinators in agricultural fields and the practices employed by farmers to maximize yield has led to a decline in insect and pollinator diversity. There is a need to better understand how ecosystem services provided by a diverse insect community scale to current farming practices as they relate to crop yield. We sought to explain how landscape heterogeneity relates to insect and pollinator diversity, as well as how insect diversity relates to crop yield across common farming practices. To evaluate how farming …


Effect Of Water Velocity And Temperature On Energy Use, Behavior, And Mortality Of Pallid Sturgeon Scaphirhynchus Albus Larvae, Joseph Thomas Mrnak Jan 2019

Effect Of Water Velocity And Temperature On Energy Use, Behavior, And Mortality Of Pallid Sturgeon Scaphirhynchus Albus Larvae, Joseph Thomas Mrnak

Electronic Theses and Dissertations

Pallid Sturgeon Scaphirhynchus albus are a federally endangered species endemic to the Missouri River basin. Natural reproduction has been limited for decades and a recruitment bottleneck is hypothesized to occur during the larval stage of development. Understanding factors that affect survival of Pallid Sturgeon larvae is key given their critical status and ongoing recovery efforts. In this study, I evaluated the effects of water velocity and temperature on energy use, behavior, and mortality of endogenously feeding Pallid Sturgeon larvae (< 25 mm TL). In the first experiment, I examined the effect of water velocity (0 – 8.3 cm s−1) on larval growth, energy density, swimming activity, and mortality. Larval growth rate at 16.3 °C was similar across …


Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson Jan 2019

Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson

Electronic Theses and Dissertations

The lack of suitable habitat conditions for beneficial organisms in simplified agroecosystems leads to unstable invertebrate communities and overreliance on chemical control of herbivores. It is possible to manage pest populations without agrichemicals by manipulating farmland so that herbivores are impaired by plant-driven bottom-up and enemy-driven top-down antagonisms. Interseeding cover crops between established crop rows is a method used by farmers to improve habitat suitability for natural enemies and hinder host-finding, feeding and movement by herbivores. Here I address three important research gaps related to interseeding cover crops. A calcium carbonate seed coating, used to improve seed-broadcasting efficiency, was tested …


Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey Jan 2019

Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey

Electronic Theses and Dissertations

Increased nutrient availability has been widely linked to the success of invasive plants, however a general mechanism explaining these observations is lacking. Stoichiometric homeostasis (H), which is the regulation of internal nutrient concentrations, has been used to explain changes in plant community diversity under alterations in nutrient availability. One hypothesis holds that plants with high regulation (larger H) decrease in abundance in nutrient enriched conditions but are stable in nutrient deficient and drought conditions, likely due to extensive root systems. Additionally, plants with low regulation (lower H) increase in abundance under nutrient enriched conditions but are sensitive to drought …


Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan Jan 2019

Prairie Dogs And Livestock In Rangeland Systems: Balancing Biodiversity And Production In The Northern Mixed-Grass Prairie, Jameson Robert Brennan

Electronic Theses and Dissertations

A major constraint of beef production within the Standing Rock Reservation has been identified as a reduction in rangeland quality due in large part to wide-scale colonization by black-tailed prairie dogs (Cynomys ludovicianus). The desire exists within the community to design a holistic framework which incorporates livestock management with the goal of increasing production and rangeland health while still maintaining increased diversity associated with prairie dogs. Prairie dogs reduce the carrying capacity of cattle on rangelands by up to 50% on occupied hectares through direct consumption of vegetation and waste due to clipping to improve detection of predators. Livestock stocking …


The Tortoise (Wildfire) And The Hare (Heavy Winter Grazing) For Promoting Heterogeneity And Improving Ecosystem Services, Lucas W. Zilverberg Jan 2019

The Tortoise (Wildfire) And The Hare (Heavy Winter Grazing) For Promoting Heterogeneity And Improving Ecosystem Services, Lucas W. Zilverberg

Electronic Theses and Dissertations

The Northern Great Plains (NGP) mixed-grass prairie developed under fire, grazing, and periodic droughts, which created a heterogeneous landscape. Since European settlement, heterogeneous landscapes have declined due to fire suppression and the maximization of livestock production, leading to the need for an alternative management practice. Our overall project objective was to determine if heavy winter grazing could be used as an alternative to patch-burn grazing for promoting heterogeneity and improving ecosystem services in the NGP. Fire has been used very effectively in patch-burn grazing management to create heterogeneity in pastures in some areas, however burning is not readily adopted in …


Bacterioplankton Biogeography Of The Mississippi River Basin, Jason Taylor Payne Jan 2019

Bacterioplankton Biogeography Of The Mississippi River Basin, Jason Taylor Payne

Electronic Theses and Dissertations

Bacterioplankton are important structural and functional components of river networks yet their biogeographical patterns in these systems are largely unknown. Using Illumina sequencing of the 16S rRNA gene we characterized variation in bacterioplankton community alpha diversity (within-sample richness of operational taxonomic units OTUs) and beta diversity (between-sample differences in composition) (1) along a 1 300-km downstream reach of the Mississippi River (2) over a range of temporal scales in the Lower Mississippi River (LMR) and (3) along cross-sectional transects repeated monthly for six months across the LMR floodplain. Particle-associated assemblages were richer in bacterial OTUs and more productive than free-living …


The Influence Of Site Connectivity On Zooplankton Assemblage Dynamics Within The Lower Mississippi River Floodplain, Jarrod Sackreiter Jan 2019

The Influence Of Site Connectivity On Zooplankton Assemblage Dynamics Within The Lower Mississippi River Floodplain, Jarrod Sackreiter

Electronic Theses and Dissertations

Zooplankton are important components of the food web of such lotic systems. Although capable of motility, they are weak swimmers and their distribution and community composition across a floodplain is strongly affected by patterns of water flow and hydrologic connectivity. However, there has been little research on the zooplankton dynamics of large rivers, such as the Lower Mississippi River (LMR). From morphological identification of zooplankton across the connectivity gradient, I assessed the degree to which hydrologic connectivity acts as an explanatory factor influencing spatial and temporal variation in zooplankton assemblage structure. Second, I compared the use of morphological identification to …


Assessing The Effects Of Habitat And Manatee Exclusion Devices On Red Drum (Sciaenops Ocellatus) Movement Patterns In Estuarine Impoundments, Steven Baker Jan 2019

Assessing The Effects Of Habitat And Manatee Exclusion Devices On Red Drum (Sciaenops Ocellatus) Movement Patterns In Estuarine Impoundments, Steven Baker

Electronic Theses and Dissertations

The Integrate-Transfer-Launch (ITL) complex impoundments located within the Kennedy Space Center security zone are known spawning sites for red drum (Sciaenops ocellatus). However, recent construction of manatee exclusion bollards around culverts leading into these impoundments may impede movement to and from this critical habitat. The goals of this study were to: 1) utilize passive acoustic telemetry to document patterns of red drum movement and habitat use within and around the ITL impoundments to assess how manatee exclusion bollards and environmental conditions may impact movement of red drum; and 2) explore red drum movement in response to environmental disturbance, specifically a …


Temperature And Polyunsaturated Fatty Acid’S Effect On Daphnia Magna Reproduction, Mark Albright Dec 2018

Temperature And Polyunsaturated Fatty Acid’S Effect On Daphnia Magna Reproduction, Mark Albright

Electronic Theses and Dissertations

Organisms adapt to their environments by adjusting their biochemistry and physiology; such adaptation is limited by resource availability and physiological constraints. The freshwater crustacean Daphnia magna inhabits a wide range of environments and must survive and reproduce within a range of temperatures. One limit to low-temperature adaptation is thought to be the availability of unsaturated fatty acids necessary to maintain proper fluidity of cellular membranes. D. magna maintained at 10 ºC on a diet poor in unsaturated fatty acids have been observed to produce clutches that fail to develop. However, this has not been observed on a diet rich in …


Impacts Of Ammonia And Temperature On Freshwater Snail Behavior And Physiology., Megan Christine Dewhatley Dec 2018

Impacts Of Ammonia And Temperature On Freshwater Snail Behavior And Physiology., Megan Christine Dewhatley

Electronic Theses and Dissertations

Gastropods are one of the most imperiled groups of animals in North America, yet there are major gaps in the literature pertaining to pollutants and climate change, and especially sublethal impacts. This dissertation assesses the effects of climate warming and unionized ammonia (NH3), one of the most abundant water pollutants, on the behavior and physiology of two caenogastropod snails: fine-ridged elimia (Elimia semicarinata) and Shawnee rocksnails (Lithasia obovata) (Gastropoda: Neotaenioglossa: Pleuroceridae). Righting behavior, or the movement used by snails to turn themselves right-side-up, was used as the main endpoint; delays in this behavior compromise …


Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney Aug 2018

Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney

Electronic Theses and Dissertations

Oak savannas were once an abundant vegetation type in the Midwestern United States that have now declined to <1% of their original distribution. Historically, natural disturbances such as periodic fire and grazing maintained oak savannas, but these have been reduced or eliminated, resulting in woody encroachment and subsequent habitat loss and degradation. In 2009-10, a baseline, pre-restoration study was completed to determine vegetation characteristics, breeding bird abundances, nest success, and nest site selection at the Gus Engeling Wildlife Management Area (GEWMA) in eastern Texas. The results showed a lack of savanna vegetation structure on degraded sites and few savanna or grassland obligate bird species. The goal of this study was to determine how breeding birds of oak savanna vegetation types in eastern Texas respond to restoration effects 7 years after initial management. Post-restoration surveys completed in 2016-17 showed a change in avian assemblages from a more woodland dominated community to grassland/savanna community. The presence and breeding of savanna obligate species dickcissel (Spiza americana) and lark sparrow (Chondestes grammacus) indicates that the restoration was successful. The presence of savanna species can be linked to the herbaceous vegetation that was restored to more closely resemble historic oak savanna structure and can quantify the success of restoration efforts.


Analysis Of Hybridization Between Native And Invasive Pupfishes (Cyprinodon), Kristina Ayers Aug 2018

Analysis Of Hybridization Between Native And Invasive Pupfishes (Cyprinodon), Kristina Ayers

Electronic Theses and Dissertations

Invasive species are detrimental to native species and when hybridization is involved a decrease in biodiversity may result. Cyprinodon variegatus is an invasive species that has caused devastation to several Cyprinodon species through rapid hybridization and genetic introgression. Cyprinodon rubrofluviatilis is native to the Brazos, Wichita and Red Rivers but fish collected between 2006-2012 from the Brazos River expressed intermediate morphological traits suggesting hybridization had occurred. My objective was to investigate if C. variegatus and C. rubrofluviatilis had hybridized in the Brazos River and if so, to determine the extent of introgression. Molecular analysis of specimens collected between 2013-2017 identified …


The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley Aug 2018

The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley

Electronic Theses and Dissertations

The Cave Salamander, Eurycea lucifuga (Rafinesque, 1822), is a little-known species, yet a common inhabitant of caves in the eastern United States. Salamanders are often important components of ecological communities and ecosystems, influencing critical processes such as nutrient cycling and community composition through their predation on invertebrates. Cave-dwelling salamanders such as E. lucifuga may thus appreciably influence the relatively simple ecosystems and communities of caves. Any such influence may be particularly important because these habitats and the organisms that reside in them are often of conservation concern. I used non-invasive methods to study the demographics, movements, and habitat selection of …


Dead Wood And Decomposition In A Tropical Forest : Vertical Patterns, Long-Term Processes, And The Role Of Lightning., Evan Matthew Gora Aug 2018

Dead Wood And Decomposition In A Tropical Forest : Vertical Patterns, Long-Term Processes, And The Role Of Lightning., Evan Matthew Gora

Electronic Theses and Dissertations

This dissertation investigates the distribution, production, and decomposition of dead wood (or woody debris) in a lowland tropical forest within the Barro Colorado Nature Monument in Panama. Although the importance of woody debris is widely accepted, information describing components of WD pools and fluxes is generally separated in both time and space, particularly in understudied tropical forests. Here I provide a comprehensive inventory of woody debris in a lowland tropical forest (Chapter 1). Woody debris is highly aggregated and difficult to quantify, and this study demonstrates that historic estimates of woody debris pools and fluxes underestimate their uncertainty. In a …