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Use Of Uav Imagery And Nutrient Analyses For Estimation Of The Spatial And Temporal Contributions Of Cattle Dung To Nutrient Cycling In Grazed Ecosystems, Amanda E. Shine Dec 2019

Use Of Uav Imagery And Nutrient Analyses For Estimation Of The Spatial And Temporal Contributions Of Cattle Dung To Nutrient Cycling In Grazed Ecosystems, Amanda E. Shine

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Nutrient inputs from cattle dung are crucial drivers of nutrient cycling processes in grazed ecosystems. These inputs are important both spatially and temporally and are affected by variables such as grazing strategy, water location, and the nutritional profile of forage being grazed. Past research has attempted to map dung deposition patterns in order to more accurately estimate nutrient input, but the large spatial extent of a typical pasture and the tedious nature of identifying and mapping individual dung pats has prohibited the development of a time- and cost-effective methodology. The first objective of this research was to develop and validate …


Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason Dec 2019

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …


Species Richness And Ecological Diversity Of Myxomycetes And Myxomycete-Like Organisms In The Tropical Forests Of Brazil, Isadora Lima Coelho Dec 2019

Species Richness And Ecological Diversity Of Myxomycetes And Myxomycete-Like Organisms In The Tropical Forests Of Brazil, Isadora Lima Coelho

Graduate Theses and Dissertations

Tropical rain forests cover less than two percent of Earth's surface, yet they sustain the greatest diversity of living organisms on the planet. Tropical rain forests cover nearly 73% of the Brazilian territory and besides harboring some of the most biodiverse ecosystems on the planet, this vast area also houses about 83% of the Brazilian population. Approximately 175 million people live in urban and rural areas with fragments of coverage of these biomes which contributes to the loss of biodiversity that rapidly increases over the years. Furthermore, the majority of the taxonomic and ecological efforts to describe and protect the …


Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal Dec 2019

Ecology And Conservation Of Shrubland Bird Communities In The Eastern Ghats Of Indi, Anant Deshwal

Graduate Theses and Dissertations

Anthropogenic disturbance, in its multiple facets represents a major threat to biodiversity and habitat quality. Consequently, extensive research is guided towards understanding anthropogenic disturbance and their effects on wildlife for development of wildlife management plans. However, for development of effective wildlife management plans it is imperative that we understand the habitat use and preference by local fauna along with effects of anthropogenic presence. In this dissertation, I studied the habitat usage and preferences of Shrubland birds in the Eastern Ghats of India during the pre-monsoon and post monsoon seasons. Eastern Ghats show a marked difference from pre-monsoon season to post-monsoon …


Eastern Collared Lizard (Crotaphytus Collaris) Population Declines In Ozark Landscapes: An Assessment Of Environmental Constraints., Casey L. Brewster Dec 2019

Eastern Collared Lizard (Crotaphytus Collaris) Population Declines In Ozark Landscapes: An Assessment Of Environmental Constraints., Casey L. Brewster

Graduate Theses and Dissertations

The Eastern Collared Lizard (Crotaphytus collaris) has experienced extensive population declines over the past half century in the Ozark Mountains. Previous research suggests that glade habitat degradation through woody vegetation encroachment is an important factor resulting in population declines. In this dissertation I used information on time-energy budgets to investigate the link between habitat degradation and shifts in life history traits likely resulting in population declines of Eastern Collared Lizards (Crotaphytus collaris) in the Ozarks. In chapter one, I addressed the influence of dense woody vegetation encroachment on age-specific growth, body size, body condition and reproduction of C. collaris in …


Snowshoe Hare (Lepus Americanus) Abundance In Relation To Habitat And Predator Assemblage Across The Apostle Islands, Jarod Reibel Dec 2019

Snowshoe Hare (Lepus Americanus) Abundance In Relation To Habitat And Predator Assemblage Across The Apostle Islands, Jarod Reibel

Masters Theses

Snowshoe hares (Lepus americanus) are a climate sensitive species that have a southern range boundary moving northward. Snowshoe hares are found on the Apostle Islands, Wisconsin which are near their southern boundary and differ by island in vegetative and carnivore communities. The archipelago serves as a natural laboratory to assess how top-down and bottomup forces interact and impact snowshoe hare populations. The objectives of this study were to determine the influence of vegetative characteristics, specifically visual obstruction, and the presence of predators on snowshoe hare abundances across the Apostle Islands. We conducted fecal pellet surveys to estimate hare abundance, measured …


The Implementation Of Qpcr Beach Monitoring Methods: Analysis Of A Multi-Lab Validation Study And The Role Of Environmental Parameters On A Comparison Of Colilert And Qpcr Methods, Molly J. Lane Dec 2019

The Implementation Of Qpcr Beach Monitoring Methods: Analysis Of A Multi-Lab Validation Study And The Role Of Environmental Parameters On A Comparison Of Colilert And Qpcr Methods, Molly J. Lane

Masters Theses

Public beaches are routinely tested for potentially pathogenic bacteria to protect beachgoers from possible illness. An EPA approved method, Colilert™, used for testing E. coli in recreational water requires 18 – 22 hours before a result is reported but, recreators have already contacted unsafe water before the beach is closed. My study focused on a U.S. EPA proposed qPCR method (Draft Method C) to quantify E. coli in recreational waters that can provide same-day results. In Chapter 2, I examined the calibration procedure used to validate Draft Method C and compared standard curve intercept and slope estimates calculated with a …


Impacts Of Shoreline Restoration And Source Of Nutrient Enrichment On Macrophytes And Epiphytic Algal Communities, Paige Marie Kleindl Dec 2019

Impacts Of Shoreline Restoration And Source Of Nutrient Enrichment On Macrophytes And Epiphytic Algal Communities, Paige Marie Kleindl

Masters Theses

Macrophytes and their epiphytic algal communities are integral for optimizing littoral ecosystem functioning in lakes. Epiphytic algae’s placement on the plant’s surface can reduce light and nutrient availability (i.e., nitrogen and phosphorus) for the host macrophyte. Macrophyte and epiphytic algal proximity complicates these primary producer group interactions and responses to bioavailable nutrients in the water column or porewater. For example, epiphytic algae may have a competitive advantage over surface water nutrients compared to macrophytes, which may have a competitive advantage over porewater nutrients via root systems.

Muskegon Lake’s industrial history and designation as an Area of Concern prompted shoreline restoration, …


Habitat Use Of The Climate-Sensitive Snowshoe Hare (Lepus Americanus) In The Manistee National Forest In Michigan’S Lower Peninsula, Spencer D. West Dec 2019

Habitat Use Of The Climate-Sensitive Snowshoe Hare (Lepus Americanus) In The Manistee National Forest In Michigan’S Lower Peninsula, Spencer D. West

Masters Theses

Snowshoe hares (Lepus americanus) are a wide-ranging lagomorph that are important forest herbivores and a popular game species throughout their range. Across the southern boundary of their geographic range, snowshoe hares are experiencing population declines and possible extirpation due to increased predation pressure driven by climate change induced camouflage mismatch, competition for forage, degraded and fragmented habitat. One method of reversing the negative trends in snowshoe hare distribution is to increase and improve available hare habitat. A specific habitat analysis for local regions will most effectively advise managers how to target habitat management. I radio-collared 11 snowshoe hares in the …


Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding Dec 2019

Mammal Species Inventory Using Various Trapping Methods In Zone 4 Of Billy Barquedier National Park, Belize During Rainy Season, Mersady Redding

Animal Science Undergraduate Honors Theses

Belize is a small country, but it is extremely ecologically diverse. Based on the few studies conducted in Belize, the abundance of mammals is low but diversity is high. Particular findings note the number and identity of species differed between four sites in the Maya Mountains of Belize, indicating that a data set from a single site is not representative of the Neotropical region. Insufficient data is available to estimate current species richness of many areas in Belize, including Billy Barquedier National Park (BBNP). The objective of this study was to explore trapping and documentation methods of terrestrial mammals in …


Freshwater Turtle Community Composition In Mined Land Strip Pit Lakes And The Effects Of Learned Trap Avoidance On Capture Rates Of Sternotherus Odoratus And Trachemys Scripta, Ethan Craig Hollender Dec 2019

Freshwater Turtle Community Composition In Mined Land Strip Pit Lakes And The Effects Of Learned Trap Avoidance On Capture Rates Of Sternotherus Odoratus And Trachemys Scripta, Ethan Craig Hollender

Graduate Theses/Dissertations

Turtles are among the most threatened groups of organisms on the planet and as such are in need of protected habitat where healthy communities can be maintained. The reclamation of land that was formerly the site of surface strip mining provides a matrix of reclaimed terrestrial landscapes rich with lakes and ponds that have the potential to function as such habitat. To determine the suitability of these habitats for turtle communities, I compared the turtle communities of strip pit lakes and natural lakes in southeastern Kansas. Of the seven species of aquatic turtle I encountered, Common Snapping Turtles (Chelydra …


Behavioral Aspects Of Chemoreception In Juvenile Cottonmouths (Agkistrodon Piscivorus), Chelsea E. Martin Dec 2019

Behavioral Aspects Of Chemoreception In Juvenile Cottonmouths (Agkistrodon Piscivorus), Chelsea E. Martin

Graduate Theses/Dissertations

For snakes, chemical recognition of predators, prey, and conspecifics has important ecological consequences. For example, detection of predator cues can reduce predation risk. Similarly, scent trailing of conspecifics to communal hibernacula can improve overwinter survival for neonates. I used y-maze choice trials to examine scent-trailing ability of 32 captive-born juvenile cottonmouths (Agkistrodon piscivorus) in two separate experiments. In conspecific trailing tests, subjects preferred to follow cues from their own mothers over a blank control cue, but also preferred to trail cues from unrelated adult females compared to cues from their own mothers. My results are consistent with previous …


Distinguishing Anuran Species By High-Resolution Melting Analysis Fo The Coi Barcode (Coi-Hrm), Steven Everman, Shiao Y. Wang Dec 2019

Distinguishing Anuran Species By High-Resolution Melting Analysis Fo The Coi Barcode (Coi-Hrm), Steven Everman, Shiao Y. Wang

Faculty Publications

Taxonomic identification can be difficult when two or more species appear morphologically similar. DNA barcoding based on the sequence of the mitochondrial cytochrome c oxidase 1 gene (COI) is now widely used in identifying animal species. High‐resolution melting analysis (HRM) provides an alternative method for detecting sequence variations among amplicons without having to perform DNA sequencing. The purpose of this study was to determine whether HRM of the COI barcode can be used to distinguish animal species. Using anurans as a model, we found distinct COI melting profiles among three congeners of both Lithobates spp. and Hyla spp. Sequence variations …


Genetic Diversity Of Blue Wildebeest (Connochaetes Taurinus) In The Liuwa Plain Of Zambia, Stephanie J. Szarmach Dec 2019

Genetic Diversity Of Blue Wildebeest (Connochaetes Taurinus) In The Liuwa Plain Of Zambia, Stephanie J. Szarmach

All NMU Master's Theses

Advances in DNA sequencing are enabling researchers to identify and genotype large sets of single nucleotide polymorphisms (SNPs) in non-model organisms to answer questions concerning ecology, evolution, and conservation. Analysis of SNP allele frequencies can provide insight into the amount of genetic diversity present in a population, connectivity between populations, and historical demographic changes. The blue wildebeest (Connochaetes taurinus) plays an important ecological role in many African savanna ecosystems, but little is known about the level of genetic diversity within most populations or the amount of gene flow that occurs between populations. In particular, the wildebeest in the …


Genetic Relationships Using Mitochondrial Versus Nuclear Markers: Is The Catfish Rag1 Gene Suitable For Species Differentiation In The Family Pangasiidae?, Huong Thanh Hoang Dec 2019

Genetic Relationships Using Mitochondrial Versus Nuclear Markers: Is The Catfish Rag1 Gene Suitable For Species Differentiation In The Family Pangasiidae?, Huong Thanh Hoang

Graduate Theses and Dissertations

The Mekong River located in Southeast Asia is a global “hotspot” for aquatic biodiversity. It includes an extensive variety of fish species second only to the Amazon River in South America. Recent studies have revealed the impacts of anthropogenic and climate factors on this river system. Such impacts can result in the formation of barriers, which divide a species population and impede gene flow between separated sub-populations. Barriers influence evolutionary trajectories resulting in the generation of geographic variants or subspecies from an ancestral population. Catfish (Teleostei: Siluriformes) are a key species of the Mekong River ecosystem and are an essential …


Effects Of Infanticide Risk And Timber Harvest On American Black Bear Space Use, D. Cody Norton Dec 2019

Effects Of Infanticide Risk And Timber Harvest On American Black Bear Space Use, D. Cody Norton

All NMU Master's Theses

Space use is an important aspect of bear ecology that maybe influenced by infanticide risk and timber harvest. I used generalized linear mixed models (GLMM) to determine if female American black bear (Ursus americanus) space use was consistent with avoidance behavior to reduce infanticide risk in the Upper Peninsula of Michigan during the 2009–2011 and 2013–2014 breeding seasons. Females with cubs occupied core areas and home ranges of similar size and relative probability of male use to females without cubs. Additionally, females with cubs did not reduce movements during times of day when male movements were greatest. Female …


Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith Dec 2019

Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith

School of Biological Sciences: Faculty Publications

The catastrophic loss of large-bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ13C) and nitrogen …


Preface For Special Section On Archaeoparasitology: A Global Perspective On Ancient Parasites And Current Research Projects, Jong Yil Chai, Min Sea, Karl Reinhard, Dong Hoon Shin Dec 2019

Preface For Special Section On Archaeoparasitology: A Global Perspective On Ancient Parasites And Current Research Projects, Jong Yil Chai, Min Sea, Karl Reinhard, Dong Hoon Shin

Karl Reinhard Publications

Archaeoparasitological research has rapidly developed in recent years, entering a new stage of improved understanding of our ancestors’ parasitic infections across the world. This progress is based on a variety of recently developed research techniques. During a period of rapid innovation since 2016, there has been no much opportunity for parasitologists to gather and share in-depth views about this novel research field. This was remedied by the 14th International Congress of Parasitology (ICOPA) held in Korea (Aug. 19-24, 2018; EXCO, Daegu). For archaeoparasitologists, ICOPA provided a unique opportunity to gather and exchange research and ideas. The participation was unprecedented in …


Confusing A Pollen Grain With A Parasite Egg: An Appraisal Of “Paleoparasitological Evidence Of Pinworm (Enterobius Vermicularis) Infection In A Female Adolescent Residing In Ancient Tehran”, Morgana Camacho, Karl Reinhard Dec 2019

Confusing A Pollen Grain With A Parasite Egg: An Appraisal Of “Paleoparasitological Evidence Of Pinworm (Enterobius Vermicularis) Infection In A Female Adolescent Residing In Ancient Tehran”, Morgana Camacho, Karl Reinhard

Karl Reinhard Publications

There is often the risk of confusing pollen grains with helminth eggs from archaeological sites. Thousands to millions of pollen grains can be recovered from archaeological burial sediments that represent past ritual, medication and environment. Some pollen grain types can be similar to parasite eggs. Such a confusion is represented by the diagnosis of enterobiasis in ancient Iran. The authors of this study confused a joint-pine (Ephedra spp.) pollen grain with a pinworm egg. This paper describes the specific Ephedra pollen morphology that can be confused with pinworm eggs.


Pinworm Infection At Salmon Ruins And Aztec Ruins: Relation To Pueblo Iii Regional Violence, Karl Reinhard, Morgana Camacho Dec 2019

Pinworm Infection At Salmon Ruins And Aztec Ruins: Relation To Pueblo Iii Regional Violence, Karl Reinhard, Morgana Camacho

Karl Reinhard Publications

The study of coprolites has been a theme of archaeology in the American Southwest. A feature of archaeoparasitology on the Colorado Plateau is the ubiquity of pinworm infection. As a crowd parasite, this ubiquity signals varying concentrations of populations. Our recent analysis of coprolite deposits from 2 sites revealed the highest prevalence of infection ever recorded for the region. For Salmon Ruins, the deposits date from AD 1140 to 1280. For Aztec Ruins, the samples can be dated by artifact association between AD 1182-1253. Both sites can be placed in the Ancestral Pueblo III occupation (AD 1100-1300), which included a …


Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby Dec 2019

Effects Of Water Table Depth And Edaphic Characteristics On Plant Diversity In A Southern Mississippi Pitcher Plant Bog, Patrick Kirby

Master's Theses

This study examined the effects that water table depth and soil characteristics have on plant species richness and species composition within pitcher plant bogs across seasons. Eight piezometers were installed at random distances to monitor long-term water table depth and pressure fluctuations along a ~710-meter line transect traversing upland and bog habitats. Vegetation sampling quadrats (n=128) were set up near each piezometer. Cover data and water table depths were collected in spring and late summer. Soil samples collected from each treatment group were used to obtain soil texture and nutrient data. The summer collection period yielded a total gdiversity of …


The Prairie Naturalist, Vol. 51, Issue 2, December 2019 Dec 2019

The Prairie Naturalist, Vol. 51, Issue 2, December 2019

The Prairie Naturalist

45 EDITOR’S NOTE: Final Thoughts as Editor-in-Chief, by Christopher N. Jacques

RESEARCH ARTICLES

47 Bats of the Loess Hills Ecoregion of Southeast Nebraska, by Virgil Brack, Jr., Dale W. Sparks, and Darwin C. Brack

58 Serological Survey and Pathogen Exposure of Adult Female White-tailed Deer in the Western Dakotas, by Katherine L. Moratz, Bailey S. Gullikson, Eric S. Michel, Daniel M. Grove, Jonathan A. Jenks, and William F. Jensen

68 Factors Limting Reintroduced Plains Topminnow, Fundulus sciadicus, Populations in Central Great Plains Streams, by Joseph D. Thiessen, Keith D. Koupal, and Casey W. Schoenebeck

NOTES

77 Recent Observations of Water …


Factors Limiting Reintroduced Plains Topminnow, Fundulus Sciadicus, Populations In Central Great Plains Streams, Joseph Thiessen, Keith D. Koupal, Casey W. Schoenebeck Dec 2019

Factors Limiting Reintroduced Plains Topminnow, Fundulus Sciadicus, Populations In Central Great Plains Streams, Joseph Thiessen, Keith D. Koupal, Casey W. Schoenebeck

The Prairie Naturalist

The plains topminnow (Fundulus sciadicus) is an endemic Great Plains stream fish that has experienced declines in geographic range and local abundance. Due to these declines, the species has been considered for federal protection and designated with conservation status in states throughout its historic range. The reasons for declines are likely similar to hypothesized factors for other endemic stream fish declines in the Great Plains. To investigate potential limiting factors a suite of 17 historic sites with reintroduced plains topminnow populations across Nebraska were evaluated for current populations and if plains topminnow were absent, additional fish were introduced. …


Review Of Grasslands And Climate Change By David J. Gibson And Jonathan A. Newman, Neal D. Noemuth Dec 2019

Review Of Grasslands And Climate Change By David J. Gibson And Jonathan A. Newman, Neal D. Noemuth

The Prairie Naturalist

The last decade has seen an explosion of information about climate change, some of which is contradictory, much of which is confusing, and the entirety of which is too much for the typical biologist or scientist to assemble and comprehend. This is why reviews such as Grasslands and Climate Change, edited by David Gibson and Jonathan Newman, are so valuable. To produce this review of climate change issues and influences relative to grasslands, Gibson and Newman recruited 30 scientists—predominantly from Europe and North America—who wrote 19 chapters dealing with various aspects of grasslands and climate change. The chapters are grouped …


The Effects Of Ship Wakes In The Venice Lagoon And Implications For The Sustainability Of Shipping In Coastal Waters, Gian Marco Scarpa, Luca Zaggia, Giorgia Manfe, Giuliano Lorenzetti, Kevin E. Parnell, Tarmo Soomere, John Rapaglia, Emanuela Molinaroli Dec 2019

The Effects Of Ship Wakes In The Venice Lagoon And Implications For The Sustainability Of Shipping In Coastal Waters, Gian Marco Scarpa, Luca Zaggia, Giorgia Manfe, Giuliano Lorenzetti, Kevin E. Parnell, Tarmo Soomere, John Rapaglia, Emanuela Molinaroli

Biology Faculty Publications

We analyse the impact of ship traffic in the vicinity of navigation channels in a wide shallow waterbody. The crucial hydrodynamic driver in this situation is the depression (Bernoulli) wake that may be transferred into a long-living solitary wave of depression over the shoals. The analysis considers navigation channels in the Venice Lagoon using a new large dataset of approximately 600 measured wake events associated to specific ships whose data are provided by the AIS system. Since the development of the modern industrial port and the opening of the Malamocco–Marghera channel in the late 1960s, growing pressure on the lagoon …


Assessing & Protecting Dark Night Skies In El Morro National Monument, Leslie Kobinsky Dec 2019

Assessing & Protecting Dark Night Skies In El Morro National Monument, Leslie Kobinsky

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Light pollution is causing the disappearance of dark night skies around the world. In the United States alone, 1/3 of people are unable to see the Milky Way where they live (Ramlagan, 2016). National Park Service sites contain some of the darkest skies in the country. Here at El Morro National Monument, these dark skies are a beautiful and healthy benefit to people in the local community and visitors traveling from afar. El Morro’s current park legislation does not include specific measures of protection for the night sky. This capstone project will create a baseline data set of night sky …


The Response Of Utah Lake's Plant And Algal Community Structure To Cultural Eutrophication, Leighton R. King Dec 2019

The Response Of Utah Lake's Plant And Algal Community Structure To Cultural Eutrophication, Leighton R. King

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Human activities have long had a negative impact on the water quality of freshwater lakes around the world. Utah Lake, located in north-central Utah, has been a subject of such impacts, as the lake experiences recurrent harmful algal blooms during the summer months. Lake warnings and closures have made the public increasingly aware of the ecological and economic impact of these blooms. The objectives of this study were to: 1) compare historical and present-day water quality and ecosystem conditions using environmental data contained in sediment cores, 2) identify whether, and when, Utah Lake transitioned from clearwater to turbid conditions, and …


Effects Of Soil-Borne Pathogens On Seedling Establishment Patterns In Forest Systems, Eric P. Sodja Dec 2019

Effects Of Soil-Borne Pathogens On Seedling Establishment Patterns In Forest Systems, Eric P. Sodja

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Janzen-Connell mechanism is proposed to maintain plant diversity: predators and diseases of seeds reduce the number of seeds that survive near a parent tree, but allow seeds far from the parent tree to grow into adulthood. In the area where seeds don’t survive, seedlings from other tree species which are not affected by the seed consumer can grow. At large scales, this effect is thought to increase overall plant diversity. Soil-borne pathogens can contribute to seed mortality in this way, but we don’t know how important different parts of their lifecycle are in creating Janzen-Connell patterns. To determine the …


Drivers Of Ant Composition, Richness, And Trophic Guilds In Neotropical Iron Ore Cavities, Rodrigo A. Castro-Souza, Thais G. Pellegrini, Marconi Souza-Silva, Rodrigo L. Ferreira Nov 2019

Drivers Of Ant Composition, Richness, And Trophic Guilds In Neotropical Iron Ore Cavities, Rodrigo A. Castro-Souza, Thais G. Pellegrini, Marconi Souza-Silva, Rodrigo L. Ferreira

International Journal of Speleology

Subterranean habitats may be considered limiting for animal colonization, especially for ants, due to permanent darkness and mainly because of oligotrophic conditions. While not as deep as limestone caves, iron ore caves and other subterranean habitats may be more available for colonization because of their shallower depth. We use the richness and composition of ants to assess how differences in habitat structure affect the biodiversity and ecosystem function between cavities and surrounding epigean landscapes. We predicted that the distribution of ants would be different because of the variation in habitat structure and cavity conditions may act as a filter for …


The Effects Of Seasonal Variations, El Niño-Southern Oscillation, And Climate Change On The Tuna-Dolphin Association, Caitlynn Birch, Michael D. Scott, Zhi-Yong Yin, Lisa T. Ballance Nov 2019

The Effects Of Seasonal Variations, El Niño-Southern Oscillation, And Climate Change On The Tuna-Dolphin Association, Caitlynn Birch, Michael D. Scott, Zhi-Yong Yin, Lisa T. Ballance

Theses

Tuna and dolphins swim together in the waters of the eastern tropical Pacific, and this association has long benefitted tuna fishermen and intrigued scientists. Although the tuna-dolphin association is often referred to as a “mystery,” much is known about the association. Yellowfin tuna are primarily caught with spotted dolphins and, to a lesser extent, spinner dolphins; historically the spotted dolphin has borne the brunt of the bycatch mortality. The tuna-dolphin association is thought to be a product of the distinct oceanography of the ETP: a shallow mixed layer, a thick oxygen minimum zone, and warm surface waters. As the mixed …