Terrestrial and Aquatic Ecology Commons^™

Influence Of Stream Permanence, Predation, And Invasive Species On Crayfish In The Ozark Highlands With An Emphasis On Species Of Greatest Conservation Need (Orconectes Marchandi, Orconectes Eupunctus And Cambarus Hubbsi), Allyson Noelle Yarra

Graduate Theses and Dissertations

Due to the ecological importance of crayfish and the increasing vulnerability of freshwater systems due to habitat loss, invasive species, and hydrologic alteration, understanding crayfish-environment relationships is crucial in the context of aquatic species conservation. I sought to examine the influence of hydrologic variation among intermittent and permanent streams on crayfish occupancy, abundance, predation risk, and potential vulnerability to invasive species effects. I conducted crayfish and environmental data sampling during two consecutive summers across 20 Ozark streams of differing permanence levels (10 intermittent, 10 permanent). In these same streams, I conducted fish and scat surveys over the course of four …

Phenology, Habitat Use, And The Impacts Of Wetland Management On Autumn Migrating Rails In Missouri, Auriel M.V. Fournier

Graduate Theses and Dissertations

Rails (Family: Rallidae) are among the least studied birds in North America, in large part due to their elusive nature. As a wetland-dependent species, understanding the timing of their migration and their habitat needs during migration is especially important since management needs to be timed to balance the needs of many species. I developed and verified a new distance sampling based nocturnal ATV spotlight survey because traditional call-broadcast surveys are not effective during autumn migration because of the drop off in call rate after the breeding season. These surveys allow us to ask point-level questions about what habitats rails select …

Ecological Importance Of Invader Source Population And Disturbance In Aquatic Invasions, Nicole Elizabeth Graham

Graduate Theses and Dissertations

Invasive species are a global problem and their effects on recipient ecosystems may be mediated by disturbance and intraspecific variation. Crayfish can substantially influence stream structure and function, and invasive crayfish often have differential impacts than native crayfish in aquatic ecosystems. Since species traits often vary across a distribution, it is possible that invasive crayfish from different source populations may have distinct impacts on recipient ecosystem structure and function. In the Ozark Highlands of Arkansas and Missouri, USA, invasive O. neglectus (the Ringed Crayfish) may be leading to the displacement of native O. eupunctus (the Coldwater Crayfish). The objective of …

Heterogeneity Of Avian Breeding Habitat On Grazing Lands Of The Northern Great Plains, Maggi S. Sliwinski

School of Natural Resources: Dissertations, Theses, and Student Research

Native rangelands in the Great Plains are largely privately owned and used for beef production. Vegetation heterogeneity is important for maintaining biodiversity, but private land may be more homogenous than desired. My research had two components: 1) to examine whether a variety of grazing strategies created vegetation heterogeneity in a large, intact rangeland, and 2) to understand beef producers’ attitudes about vegetation heterogeneity.

First, I sampled vegetation structure, composition, and bird abundance at multiple plots on eleven management units in Cherry County, Nebraska. Units were managed with commonly used grazing strategies (e.g., short-duration grazing and season-long continuous grazing). I examined …

Thermal And Developmental Ecology Of Pupfish, Cyprinodon, Alexander Jones

UNLV Theses, Dissertations, Professional Papers, and Capstones

Pupfish from the genus Cyprinodon are among the most endangered groups of fishes on the planet, with nearly 40% of species being threatened with extinction. These pupfishes are often assumed to be the most temperature tolerant of all fish, coping with temperatures as low as 0 °C and as high as 44 °C. However, conflicting data exist and certain measures of thermal tolerance are not markedly higher in pupfish compared to common game fish. Pupfish egg production and growth has been known to be hampered at temperatures well below what they apparently experience in nature. I addressed why eggs fail …

Effects Of Temperature Gradient, Substrate Composition, And Canopy Cover On The Spatial Distribution Of Topminnow Species: Fundulus Notatus And Fundulus Olivaceus, Austin M. King

Honors Theses

Hybrid zones are locations where two interbreeding species coexist and hybridize. The spatial distribution of ecologically similar species is of primary interest in understanding the formation and stability of hybrid zones. These hybrid zones are of significance as they allow for insight into how speciation occurs naturally within the environment. A variety of factors may play a role in determining the spatial distributions of species within hybrid zones. Examples of these factors include variations in temperature gradients, substrate composition, and changes in canopy cover. Fundulus olivaceus and Fundulus notatus are generally found within upstream and downstream habitats respectfully. These habitats …

Assessment Of The Calling Detection Probability Throughout The Day Of Two Invasive Populations Of Bullfrog (Lithobates Catesbeianus) In Uruguay, Gabriel Laufer, Noelia Gobel, Alvaro Soutullo, Claudio Martinez-Debat, Rafael O. De Sá

Biology Faculty Publications

Bullfrog invasion is a major conservation concern in South America, so there is an urgent need to detect and monitor its many invasion foci. Amphibian sampling methods commonly use calling display, specifically the nuptial calls of males. With the aim of obtaining the better day period to sample and monitor Lithobates catesbeianus presence, we recorded its calls at three ponds in two invaded localities in Uruguay (Aceguá, Cerro Largo, and San Carlos, Maldonado) during the reproductive season. Then, we studied the records, obtaining a subsample of calling intensity at the first 5 minutes for each hour. We detected that vocalization …

Living On The Edge: Assessing The Effects Of Catastrophic Fire On Plants Utilized By Two Endemic Subspecies Of Spring Mountains Butterflies, Charles Ryan Herrmann

UNLV Theses, Dissertations, Professional Papers, and Capstones

In the past few decades there has been an increase in catastrophic, high-intensity, large-scale wildfires globally due to the combination of climate warming with more than a century of fire suppression policy. One region that has been drastically affected is the Western United States, as there has been an increase in ‘mega-fires’ in the past few decades. The 2013 Carpenter 1 Fire in the Spring Mountains, Nevada was the largest fire in recorded history in these mountains, spreading out over 11,137 hectares. Catastrophic fire like the Carpenter 1 Fire can have potentially devastating effects on endemic species inhabiting refugia on …

Flight Activity, Oviposition Pit Distribution, And Emergence Densities Of Monochamus Titillator And M. Carolinensis In The Ozark-St. Francis National Forest In Arkansas, Jake Bodart

Graduate Theses and Dissertations

Monochamus (Coleoptera: Cerambycidae) are a genus of longhorn beetles commonly known as pine sawyers. They have a worldwide distribution coincident with pines (Pinaceae) and are vectors of the pinewood nematode (Bursaphelenchus xylophilus). In the United States, there are eight known Monochamus species and they have a sympatric distribution with at least one other Monochamus species throughout their range. Monochamus are known to attack stressed, dead, and dying conifers especially pines. In the Ozark- St. Francis National Forest in Arkansas, there are two species of pine sawyers and they share this sympatric distribution observed throughout the United States, M. titillator (southern …

Where In The World Are Pallas's Fish Eagles? Migration And Ecology Of Haliaeetus Leucoryphus In Asia, Marla Lynn Steele

Graduate Theses and Dissertations

Pallas’s Fish Eagle (Haliaeetus leucoryphus) is the Northern Hemisphere’s least understood eagle species. Virtually nothing is known concerning the species’ ecology. Historically, Pallas’s Fish Eagles were expected to breed in three separate populations in Mongolia, China, and India and was considered one of the most common raptors in Asia prior to the 1900’s. However, by 1960’s major declines were observed. The species is currently listed as “globally vulnerable” by the International Union for the Conservation of Nature (IUCN) Red List. The current study examined over a century of Pallas’s Fish Eagle observation data to determine occupancy and detection rates throughout …

Ecological Consequences Of Water Loss Under Climate Change In Small Ectotherms, Eric Alexander Riddell

All Dissertations

Warming climates threaten to reduce biodiversity across the planet, yet the capacity of organisms to minimize the effects of climate change are rarely considered in current ecological predictions of climate change. Organisms can minimize the effect of warming through behavioral, physiological, and morphological processes that limit exposure to lethal conditions or improve performance. Therefore, integrating these mechanisms into ecological models might improve predictions on the loss of biodiversity under climate change. For my dissertation, I focus on the physiological processes that influence habitat suitability in a group of terrestrial, lungless salamanders (Plethodon spp.) found in the core of the global …

Salting Our Freshwater Lakes, Hilary A. Dugan, Sarah L. Bartlett, Samantha M. Burke, Jonathan P. Doubek, Flora Krivak-Tetley

Dartmouth Scholarship

The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a …

Determination Of Metal Concentrations In Sediments Of Big Walnut Creek, Hayley Quinn, Joan M. Esson, Kierra M. Lathrop, Michael A. Hoggarth, Kevin Svitana, Nathan Hess

Undergraduate Distinction Papers

The freshwater mussel populations in the lower stretch of Big Walnut Creek in central Ohio have been found to vary along the run of the creek with the lowest population of mussels in the middle stretch. One possible cause for the decline is the presence of contaminants in the sediments of the creek. In this study, nine Sites along the creek were examined. At each Site, sediment samples from a pool region and two quadrants from where mussels were also studied (the area of interest) were collected, along with pseudo feces, which is the waste mussels produce as they filter …

Body Shape Diversification Of Pecos Pupfish (Cyprinodon Pecosensis) On Varying Habitats As Evaluated By Geometric Morphometrics, Qianna Xu

Masters Theses & Specialist Projects

During the 19th and 20th centuries, alterations to the Pecos River in New Mexico and Texas, USA due to anthropogenic activities, including damning and river channelization, vast water extraction for irrigation, as well as pollution of associated habitats, have greatly impacted the fish fauna within the drainage. One of the endemic fish species, the Pecos pupfish (Cyprinodon pecosensis), might be the most affected. Historically abundant and widespread large populations have been disrupted and became a series of small isolated subpopulations that persist at a few highly fragmented habitats restricted to a small area in southern New Mexico. The connectivity among …

Cyanobacterial Blooms In Highland Lake, Me, William Lambeth, Rachel Henson, Michael Morrison

Thinking Matters Symposium Archive

Cyanobacterial blooms, like algal blooms, are a much studied phenomena; and many triggers that cause these blooms are well understood. Usually, excess nutrients (such as soluble nitrogen or phosphate) are prerequisite for a bloom to occur. Since 2013, annual summer cyanobacterial blooms have been observed at Highland Lake (HL), located in Cumberland County, Maine. Data going back more than 15 years, collected by the Highland Lake Association, shows this is a new phenomenon in this body of water. Other investigators have shown HL water chemistry to have high aluminum to phosphorous and aluminum to iron ratios. These metals bind phosphate …

Mechanical Harvesting Effectively Controls Young Typha Spp. Invasion And Unmanned Aerial Vehicle Data Enhances Post-Treatment Monitoring, Shane Lishawa, Brendan D. Carson, Jodi S. Brandt, Jason M. Tallant, Nicholas J. Reo, Dennis A. Albert, Andrew M. Monks, Joseph M. Lautenbach

School of Environmental Sustainability: Faculty Publications and Other Works

The ecological impacts of invasive plants increase dramatically with time since invasion. Targeting young populations for treatment is therefore an economically and ecologically effective management approach, especially when linked to post-treatment monitoring to evaluate the efficacy of management. However, collecting detailed field-based post-treatment data is prohibitively expensive, typically resulting in inadequate documentation of the ecological effects of invasive plant management. Alternative approaches, such as remote detection with unmanned aerial vehicles (UAV), provide an opportunity to advance the science and practice of restoration ecology. In this study, we sought to determine the plant community response to different mechanical removal treatments to …

Monitoring Anuran Populations In Bosque Protector Candelaria: A Multi-Year Comparison Of Frog Populations In An Ecuadorian Cloud Forest, Mindee Goodrum

Independent Study Project (ISP) Collection

For many years, amphibian populations around the world have been declining due to climate change, habitat loss or change, and diseases such as Ranavirus or the Chytrid fungus. However, there is still a great lack of information regarding the diversity of frogs, especially in the cloud forests of Ecuador where this study was conducted. This study was conducted in April and May of 2017 in the Ecominga Reserve of Cerro Candelaria in El Placer, Ecuador. The objective was to conduct visual-encounter surveys of several sites in the reserve and compare the results to studies that have been conducted in the …

Abiotic Conditions Of Rare Pitcher's Thistle Attract Selection By An Invasive Weevil, Monica Paniagua Montoya

Lawrence University Honors Projects

Plant associations occur when host selection of a focal plant is reduced or increased by the presence of another plant species. Larinus planus is an invasive weevil whose larvae feed in the flower heads of native and federally threatened Pitcher’s thistle (Cirsium pitcheri). Studies have linked the presence of neighboring plants to increased host selection of Pitcher’s thistle by the weevil, but the factors contributing to host selection remain unknown. In our study, we determined if there were differences among abiotic factors, host selection and weevil behavior at Pitcher’s thistles surrounded by beach grass, sand and at high …

The Role Of Adult Fiddler Crab Environmental Acoustic Cues And Chemical Cues In Stimulating Molting Of Field-Caught Megalopae, Emily E. Waddell, Wendy Dow Piniak, Kathleen A. Reinsel, James M. Welch

Student Publications

In mid-Atlantic estuaries, three fiddler crab species, Uca pugilator, Uca pugnax and Uca minax co-occur, with their adults occupying different habitat types distinguished by salinity and sediment size. Some evidence exists that selective settlement is responsible for this separation but the mechanism is largely unknown. We tested the hypothesis that field-caught megalopae would accelerate metamorphosis in the presence of adult species-specific environmental acoustic cues and conspecific chemical cues. We placed megalopae in seawater with and without adult chemical cues, exposed them to one of three sound treatments for 8 days, and recorded the time each megalopa took to metamorphose. In …

Avian Species And Family Composition Along Elevational And Disturbance Gradients In Santa Fe National Park, Veraguas Province, Panamá, Benjamin Shipley

Independent Study Project (ISP) Collection

Elevational gradients are some of the most well-known and researched biological trends. However, how species diversity varies with elevation differs by taxa and location. One hypothesis suggests that bird diversity decreases with increasing elevation in the tropics. In addition, bird diversity may decrease along the forest edge and in areas of increasing disturbance. Therefore, in this study I surveyed avian diversity along an elevational gradient in Santa Fe National Park, Veraguas, Panamá using point-count observations. Thirty-six point-count locations in 3 elevation zones were surveyed between 19 Apr and 29 Apr 2017. Shannon diversity, richness, and evenness were calculated for both …