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Resiliency And Collapse: Lake Trout, Sea Lamprey, And Fisheries Management In Lake Superior, Nancy Langston

Michigan Tech Publications, Part 1

No abstract provided.

Nitrogen Biogeochemistry In Binghamton, Ny, A Medium-Sized Urban Ecosystem, Stephanie Craig

Graduate Dissertations and Theses

Humans have altered nitrogen (N) cycling on a global scale, and elevated nitrogen levels are characteristic of urban ecosystems. The major reasons that N is higher in cities include imports of food, fuel and fertilizer. High N export from both point- and nonpoint-sources is common in large cities. While N cycling has been studied in large urban areas, less is known about its cycling in medium-sized cities, such as Binghamton, N.Y. We found that point-source N exported from the Binghamton-Johnson City Wastewater Treatment Plant (B-JC WWTP) was greater than nonpoint-source N exported from eight urban streams to the Susquehanna River, …

Reef Fish And Coral Assemblages On Hospital Point And Near Bastimentos Island, Panama, Elaine Shen

Independent Study Project (ISP) Collection

Because worldwide declines coral reef health are of major concern, studying coral reefs through the lens of conservation efforts at local scales is essential for determining and monitoring effective policy measures. In the Bocas del Toro Archipelago, there are conflicts of interest between exploitative rapid tourism development, overfishing practices, and national efforts to conserve the local marine biodiversity. Coral and reef fish species abundance richness, diversity, evenness, and similarity were measured to see how coral and reef fish assemblages changed between protected and unprotected areas. A total of 329 fish and 322.5 square meters of benthos were analyzed using underwater …

The Effects Of Sub-Lethal Predation On The Reproductive Output Of Acanthaster Planci (Crown-Of-Thorns Starfish), Emily Mucha

Independent Study Project (ISP) Collection

Wide-scale declines in live coral cover have been observed throughout history. Modern day coral populations face a multitude of environmental disturbances, however one of the most devastating to the reefs in the Indo-Pacific is the crown-of-thorns starfish (Acanthaster planci), which feeds on the tissues of live corals. The rate at which these individuals feed combined with the explosion of populations in times of outbreak have been seen to exert some of the biggest pressures on coral reefs to date. Following recent episodes of crown-of-thorns starfish (COTS) outbreaks, research on the organism has become increasingly prevalent on the scientific …

Fish Diversity And Coral Health Of Tanzania's Reefs: A Comparative Study Between The Ushongo Village Reef And The Fungu Zinga Reef Over Time, Della Turque, Corinne Casper

Independent Study Project (ISP) Collection

The world’s oceans are becoming increasing acidic due to global climate change, posing a threat to marine ecosystems, including coral carbonate systems. Environmental threats are exacerbated by human development stressors as well: growing populations, dependency on marine resources, and unsustainable practices invaluable marine ecosystems at risk. Tanzania’s coral reef system extends for 3580 km2 (Muhando et al. 2008) near the Tanga region, serving over half a million people who are highly dependent on fishing and other marine resources as their livelihoods (Samoilys et. al. 2008). With Tanzania’s population rapidly growing, the unsustainable pressure on coral reefs for sustenance and livelihood …

Harpy Eagle (Harpia Harpyja) Conservation: Juvenile Behavior And Diet At A Nest Near Pijibasal, Darien, Hannah Rodgers

Independent Study Project (ISP) Collection

The Harpy Eagle (Harpia harpyja), the largest and most powerful bird of prey in the Americas, is declining throughout its range in Neotropical forests. Hunting and deforestation threaten populations in the most important remaining eagle habitat in Central America, the Darien province of Panama. These eagles may have the longest postfledging juvenile dependency of any raptor, though juvenile behavior during this period is poorly studied. This study monitored an 11-month-old juvenile for 7 days at a nest near the indigenous community of Pijibasal in order to study behavior and diet. Researchers recorded the juvenile’s location and behavior, studied prey remains …

Benthic Algae And Diatom Communities In Seagrass Meadows Under Three Different Human Impact Regimes In Bocas Del Toro, Panamá, Averyl Cheng

Independent Study Project (ISP) Collection

In Bocas del Toro, Panamá, widespread tourism has been the main source of revenue and has become an increasing threat to seagrass meadows and the organisms they support. This study aimed to investigate and describe algae and diatom communities under three different regimes of anthropogenic disturbance: high, medium and low human impact. The biodiversity was analyzed by measuring the algae and diatom assemblages with Shannon-Weiner’s Biodiversity Index, Evenness Index and Sorensen’s coefficient. The data obtained from these three diversity indices were compared to the areas along an anthropogenic disturbance gradient of high, medium and low impact. A total of 12 …

The Effects Of Sub-Lethal Predation On The Reproductive Output Of Acanthaster Planci (Crown-Of-Thorns Starfish), Emily Mucha

Independent Study Project (ISP) Collection

Wide-scale declines in live coral cover have been observed throughout history. Modern day coral populations face a multitude of environmental disturbances, however one of the most devastating to the reefs in the Indo-Pacific is the crown-of-thorns starfish (Acanthaster planci), which feeds on the tissues of live corals. The rate at which these individuals feed combined with the explosion of populations in times of outbreak have been seen to exert some of the biggest pressures on coral reefs to date. Following recent episodes of crown-of-thorns starfish (COTS) outbreaks, research on the organism has become increasingly prevalent on the scientific …

A Review Of The Welfare Impact On Pinnipeds Of Plastic Marine Debris, Andrew Butterworth

Reduction and Degradation of Habitat Collection

Uncounted, and usually unobserved, numbers of pinnipeds find themselves entangled in lost fishing gear, monofilament line, nets, rope, plastic packaging in the ocean or on the shoreline. These animals may carry debris wrapped around themselves for long periods, and often die as a result, sometimes from deep chronic wounds. The pinniped species most affected by this modern and manmade phenomenon are fur seals, monk seals, and California sea lions, and to a lesser extent gray, common, and monk seals. Entanglement rates described range up to 7.9% of local populations annually, and the common entangling materials; packing bands, fragments of lost …

Differential Plant Invasiveness Is Not Always Driven By Host Promiscuity With Bacterial Symbionts, Metha M. Klock, Luke G. Barrett, Peter H. Thrall, Kyle E. Harms

Faculty Publications, Environmental Studies

Identification of mechanisms that allow some species to outcompete others is a fundamental goal in ecology and invasive species management. One useful approach is to examine congeners varying in invasiveness in a comparative framework across native and invaded ranges. Acacia species have been widely introduced outside their native range of Australia, and a subset of these species have become invasive in multiple parts of the world. Within specific regions, the invasive status of these species varies. Our study examined whether a key mechanism in the life history of Acacia species, the legume-rhizobia symbiosis, influences acacia invasiveness on a regional scale. …

Do Novel Weapons That Degrade Mycorrhizal Mutualisms Explain Invasive Species Success?, Philip L. Pinzone Mr.

Biology Theses

Invasive plants often dominate novel habitats where they did not co-evolve with local species. Several hypotheses suggest mechanisms that explain increased exotic plant success, including 'novel weapons' and 'degraded mutualisms'. Japanese knotweed (Fallopia japonica) and European buckthorn (Rhamnus cathartica) are widespread plant invaders in North America that can dominate ecosystems. The goal of this study is to test whether these impacts are more consistent with novel weapons or degraded mutualism hypotheses. I examine tree seedling recruitment, (germination and initial survival) growth, (biomass) and mycorrhizal invasion (AMF content) as a function of F. japonica and R. cathartica …

Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon

USF Tampa Graduate Theses and Dissertations

Torrecillas Lagoon in the North Coast of Puerto Rico has experienced extensive anthropogenic influence over the past 400 years. Elevated concentrations of Potential Toxic Elements (PTEs) have been reported in surficial sediments. The main goal of this dissertation was to implement in Puerto Rico the use of benthic foraminifers as a bioindicators of PTEs and to compare the impact of Cu(II) on field samples with results of experimental work using cultures.

Analyses included geochemical assessment for bulk and carbonate- soluble bioavailable concentrations of PTEs in surface, core and pore-water samples, as well as analyses of grain-size, Percent Total Organic Carbon …

Quantitative Evidence For The Effects Of Multiple Drivers On Continental-Scale Amphibian Declines, Evan H. Campbell Grant, David A. W. Miller, Benedikt R. Schmidt, Michael J. Adams, Staci M. Amburgey, Thierry Chambert, Sam S. Cruickshank, Robert N. Fisher, David M. Green, Blake R. Hossack, Pieter T. J. Johnson, Maxwell B. Joseph, Tracy A. G. Rittenhouse, Maureen E. Ryan, J. Hardin Waddle, Susan C. Walls, Larissa L. Bailey, Gary M. Fellers, Thomas A. Gorman, Andrew M. Ray, David S. Pilliod, Steven J. Price, Daniel Saenz, Walt Sadinski, Erin Muths

Forestry and Natural Resources Faculty Publications

Since amphibian declines were first proposed as a global phenomenon over a quarter century ago, the conservation community has made little progress in halting or reversing these trends. The early search for a “smoking gun” was replaced with the expectation that declines are caused by multiple drivers. While field observations and experiments have identified factors leading to increased local extinction risk, evidence for effects of these drivers is lacking at large spatial scales. Here, we use observations of 389 time-series of 83 species and complexes from 61 study areas across North America to test the effects of 4 of the …

Plastic Pollution And The Global Throwaway Culture: Environmental Injustices Of Single-Use Plastic, Kristin L. Mcdermott

ENV 434 Environmental Justice

The global throwaway culture has created a cross-ecosystem plastic pollution injustice. The first to suffer this injustice will be the most vulnerable. Our oceans have become our dumpsters. The throwaway culture has created a disrespect of material goods that has turned the earth’s resources into rubbish after a single use. Eighty percent of the yearly 8 million tons of plastic that enter the ocean is single use plastic, such as plastic bottles, plastic shopping bags, or cigarette lighters.[1] Plastic has destroyed ecosystems, robbing impoverished communities of natural resources and of a healthy and safe living environment. First to suffer …

Changes In Floristic Composition In The State Forests In Worcester County (Massachusetts) Over 34 Years, Flor A. Monroe

Sustainability and Social Justice

ABSTRACT

CHANGES IN FOREST DIVERSITY OF STATE FOREST IN WORCESTER COUNTY, MASSACHUSETTS, OVER 34 YEARS PERIOD

The forest in Massachusetts has changed since the earliest colonial settlement and today the floristic composition is more homogeneous. This study investigates the potential change in the floristic composition over thirty years in Worcester County State Forests. Shannon, richness and evenness indices for two periods were compared, and Jaccard index was used to analyze similarity in composition between the periods. The possible influence of severe weather events was also analyzed.

It was found Changes in the floristic composition, but the magnitude of the changes …

Evaluation Of Alternative Strategies To Prevent Leopard Predation On Livestock Around Yala National Park, Sri Lanka, Sanjiv Fernando

Sustainability and Social Justice

In recent years, many livestock herders living near Yala National Park, Sri Lanka have reported livestock losses due to predation by leopards (Panthera pardus kotiya). Despite herders’ attempts to safeguard their cattle, livestock depredation remains an issue, sometimes causing herders to kill leopards in retaliation. In an effort to mitigate the human-leopard conflict, protective cattle enclosures made from steel pipes and mesh wire were introduced to prevent leopard attacks on cattle. This study aims to assess the severity of leopard predation on livestock, understand the methods used in retaliatory killings, examine the effectiveness of existing livestock protection methods, …

Spatial Ecology And Captive Behavior Of Rehabilitated Black Bears In Utah, Patrick J. Myers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Animal movements and space use are fundamental components of life and play integral roles in organismal fitness, population dynamics, and the ecology and evolution of species. The heterogeneous distribution of resources and the movement required to access them, results in ecology being a fundamentally spatial concept. Thus, elucidating animal-habitat relationships is a central focus of wildlife ecology and conservation. I utilized GPS technology, resource selection functions, and generalized linear mixed models, to investigate the immediate post-release movements, denning chronology, release-site fidelity, and season-delineated movements, home ranges, and resource use for six, orphaned and rehabilitated black bears (Ursus americanus). …

Tree-Mycorrhizal Associations Detected Remotely From Canopy Spectral Properties, Joshua B. Fisher, Sean Sweeney, Edward R. Brzostek, Tom P. Evans, Daniel J. Johnson, Jonathan A. Myers, Norman A. Bourg, Amy T. Wolf, Robert W. Howe, Richard P. Philllips

Biology Faculty Research

A central challenge in global ecology is the identification of key functional processes in ecosystems that scale, but do not require, data for individual species across landscapes. Given that nearly all tree species form symbiotic relationships with one of two types of mycorrhizal fungi – arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) fungi – and that AM- and ECM-dominated forests often have distinct nutrient economies, the detection and mapping of mycorrhizae over large areas could provide valuable insights about fundamental ecosystem processes such as nutrient cycling, species interactions, and overall forest productivity. We explored remotely sensed tree canopy spectral properties to …

Design Science 5 | Steam Intelligence, Schedule, Edna W. Lawrence Nature Lab

Design Science Symposia

Schedule of events.

Foraging Time And Food Resource Use Of Geoffroy’S Tamarin (Saguinus Geoffroyi) In An Urban Forest Landscape, Parque Natural Metropolitano, Ciudad De Panamá, Panamá, Rachael Pruitt

Independent Study Project (ISP) Collection

Saguinus geoffroyi, a small neotropical primate that ranges from the Chocó region of Colombia along the Pacific coast of Panamá to the eastern side of the Azuero peninsula. They are known to be a disturbance tolerant species and are mostly found in secondary growth and forest edges where understory growth is moderately dense. They have 3 main food sources: insects, small fruits and exudates (plant saps), which are located in different layers of the forest, although the composition of these may change depending on the season. This study attempted to determine the common food resources, foraging time and location of …

Occupancy Rates And Detection Probabilities Of Red-Backed Salamanders On The Virginia Fall Line, Jay D. Mcghee

Virginia Journal of Science

To meet the conservation needs of declining amphibian populations, there is a need to assess monitoring techniques in various habitat types and seasons. I assessed detection rates and proportion of area occupied via transect monitoring for red-backed salamanders at a site along the Virginia Fall Line in Doswell, Virginia. I established 24 transects in a 3.2-ha area in both riparian and upland habitats. Objects providing natural cover along these transects were sampled 3 times a week in fall and spring over a two-year period. Models of occupancy and detection were developed and compared using Akaike’s Information Criterion. Based on 113 …

Avifaunal Community Composition In A Tropical Forest Corridor: A Case Study From The Atherton Tableland, North Queensland, Don Jones

Independent Study Project (ISP) Collection

Bird communities in tropical forest ecosystems are highly threatened by habitat loss and fragmentation. Replanted corridors connecting isolated forest remnants are a popular method of ameliorating certain negative impacts of habitat fragmentation. Such linkages can theoretically facilitate greater dispersal, increase gene flow, and reduce the risk of local extinctions in forest birds. However, relatively few studies have examined the utilization of reforested corridors by birds, and little hard data exists to support claims that this type of resource and time intensive project is the best use of often scarce funding for conservation. This study examined the avifaunal community present in …

Epigeal Fauna Of Bosque Protector Cerro Candelaria, Justine Albers

Independent Study Project (ISP) Collection

Pitfall traps are commonly used to sample epigeal fauna, and are especially utilized for the collection of ground-dwelling arthropods; however, this sampling method has yet to be employed in Cerro Candelaria, a protected cloud forest reserve in Tungurahua, Ecuador. Pitfall trap systems were established at two different sites in the reserve that differed in elevation and forest type. Although individuals from 4 different phlya, 11 classes and 17 orders were encountered over the duration of the study, pitfalls were most effective at sampling Coleoptera, which comprised 40% of the total catch across both sites. The two communities of beetle …

Molecular Analysis Confirming The Introduction Of Nile Crocodiles, Crocodylus Niloticus Laurenti 1768 (Crocodylidae), In Southern Florida, With An Assessment Of Potential For Establishment, Spread, And Impacts., Michael R. Rochford, Kenneth L. Krysko, Frank J. Mazzotti, Matthew W. Shirley, Mark W. Parry, Joseph A. Wasilewski, Jeffrey S. Beauchamp, Christpher R. Gillette, Edward F. Metzger Iii, Michiko A. Squires, Louis A. Somma

Papers in Herpetology

The state of Florida, USA, has more introduced herpetofauna than any other governmental region on Earth. Four species of nonnative crocodilians have been introduced to Florida (all since 1960), one of which is established. Between 2000–2014 we field-collected three nonnative crocodilians in Miami-Dade County, Florida, and one in Hendry County, Florida. We used DNA barcoding and molecular phylogenetics to determine species identification and native range origin. Also, we described diet, movement, and growth for one crocodile. Our molecular analyses illustrated that two of the crocodiles we collected are most closely related to Nile Crocodiles (Crocodylus niloticus) from South Africa, suggesting …

Effects Of Environmental Factors On The Abundance Of Blacklegged Ticks, Jasmine L. Miller, Roger A. Lebrun, Howard S. Ginsberg

Senior Honors Projects

The nymphal stage of the blacklegged tick, Ixodes scapularis, is the major vector of Lyme disease, the most common vector-borne disease in North America. Tick abundance has generally been estimated using either flag/drag samples or samples from hosts. However, the biases of these sampling methods have not been adequately studied. We compared samples using both methods from sites in Massachusetts and Wisconsin. Tick abundance was compared with variables related to weather (temperature, relative humidity, and tick adverse moisture events), vegetation (canopy cover, tree density, shrub density, ground vegetation, and leaf litter cover), and host abundance (mice, small mammals, medium …

Ecosystem Services In Managing Residential Landscapes: Priorities, Value Dimensions, And Cross-Regional Patterns, Kelli L. Larson, Jennifer L. Morse, Peter M. Groffman, Neil D. Bettez, Tara Trammell

Environmental Science and Management Faculty Publications and Presentations

Although ecosystem services have been intensively examined in certain domains (e.g., forests and wetlands), little research has assessed ecosystem services for the most dominant landscape type in urban ecosystems—namely, residential yards. In this paper, we report findings of a cross-site survey of homeowners in six U.S. cities to 1) examine how residents subjectively value various ecosystem services, 2) explore distinctive dimensions of those values, and 3) test the urban homogenization hypothesis. This hypothesis posits that urbanization leads to similarities in the social-ecological dynamics across cities in diverse biomes. By extension, the thesis suggests that residents’ ecosystem service priorities for residential …

Weathering The End Times, Donald W. Holdridge Sr.

Eruditio Ardescens

“Weathering the End Times” first addresses some of the major arguments for and against man-caused Climate Change, and then portrays where the various elements of Christendom fall within this debate. It goes on to examine the prophetic Scriptures that relate to the environments of the Tribulation, Millennial Kingdom and Eternal State, concluding that God-caused Climate Change is what believers truly need to focus on.

Characterization Of Current And Historical Variations In Sediment Accretion And Carbon Dynamics At The Rice Rivers Center Kimages Creek Wetland Restoration, Melissa J. Davis, Christopher D. Gatens, Edward R. Crawford, Arif Sikder

Rice Rivers Center Research Symposium

Current research of freshwater wetland soils have assessed and reported smaller stocks of soil organic carbon in restored wetlands compared to reference natural wetlands. However, a majority of these studies focus on sites restored from agricultural draining of non-tidal depressional wetlands,whereas carbon and accretion dynamics in tidal freshwater wetlands restored via dam removal is poorly understood. The U.S. Army Corps of Engineers estimates over 80,000 dams greater than 6 feet and tens of thousands of smaller dams pepper the U.S., of which the majority are unsafe, old or no longer serve their intended purpose. Damming disrupts the natural flow of …

An Analysis Of Particulate Matter In Central Virginia, Elizabeth Garrett, Arif Sikder

Rice Rivers Center Research Symposium

Virginia is consistently rated as a state with high rates of asthma (Asthma and Allergy Foundation 2014). Although this respiratory disease has many causes, certain air pollutants can be a trigger. The EPA currently identifies, monitors, and regulates seven types of air pollutants. One of these pollutants, particulate matter, can occur both naturally and culturally. The primary anthropogenic cause of particulate matter is fly ash, which is formed during fossil fuel combustion. Different technology installed in the power plant can capture some of the fly ash but these methods are not entirely effective.

This study focused on estimating the ratio …

Greenhouse Gas Emissions Over A Tidal Cycle In A Freshwater Wetland, Joseph C. Morina, Rima B. Franklin

Rice Rivers Center Research Symposium

Tidal freshwater wetlands are located at the interface of non-tidal freshwater riverine systems and estuarine tidal systems. These habitats experience freshwater tides, creating unique redoximorphic soil characteristics while simultaneously presenting an opportunity for hydrologic nutrient transport into the system. Because of this periodic flooding and draining, tidal freshwater wetlands are systems of intense biogeochemical transformations, which are microbially mediated. Several microbial transformations (e.g., methanogenesis, incomplete denitrification, and nitrification) result in the production of greenhouse gases (CO2, CH4, and N2O) at globally-significant levels. For example, wetlands are one of the greatest sources of methane on Earth, accounting for 20-33% of the …