Life Sciences Commons^™

Effects Of Ecologically Relevant Concentrations Of Nitrate On Behavior In Betta Splendens, Sarah Janson

Honors College

Nitrate is a ubiquitous pollutant that is becoming more prevalent in both fresh and saltwater environments. Short term effects are often studied, but an organism’s response to stress can change due to whatever the stressor is. In order to research this, a study was run using environmentally relevant nitrate treatments (0 mg/L, 10 mg/L NO3-N, and 100 mg/L NO3-N) to see the effect of nitrate on scototaxis behaviors, a measure of anxiety. This study used Betta splendens because they are easy to rear and have very well documented behaviors. In addition to the scototaxis, the effect of temperature on mortality …

Winging It Through Unprecedented Times: A Study Of Avian Admissions To Wildlife Rehabilitation Centers In The Eastern United States Amidst The Covid-19 Pandemic, Thea Tengstrom

Honors College

The onset of the COVID-19 pandemic in 2020 has brought new research that examines the many ways in which humans impact wildlife. Wildlife rehabilitation is a tool that attempts to mitigate some negative effects of anthropogenic activity (domestic cats, window strikes), through specialized care to aid injured and orphaned animals. This study sought to investigate if the ‘Anthropause’, which saw a massive change in human behavior, demonstrated an influence on wild bird admissions to wildlife rehabilitation centers. Twelve centers were selected including both urban and non-urban centers throughout the eastern United States. Bird admission data between 2018 and 2021 were …

Does Urbanization Surrounding Stopping Sites Affect Migratory Behavior In American Woodcock (Scolopax Minor)?, Zoe Pavlik

Honors College

Urban landscapes may influence bird species in complex ways, with some species exploiting urban environments, others adapting to them, and others avoiding them. Migratory birds encounter urbanization not just during breeding and overwintering, but also at stopping sites during migration. Migration routes of American Woodcock (Scolopax minor), a bird species experiencing long term population declines, follow the east coast of the United States, including the major urbanized areas of the eastern seaboard. I explored the effects of urbanization around stopping sites on Woodcock migratory behavior using the percentage of impervious surfaces within a buffer surrounding the site as a measure …

Ecological Effects And Ethics Of A Species Range Shift To High Elevation Ponds, Ava Ardito

Honors College

As temperatures warm, the climate crisis is having a significant influence on species across the world and altering their distributions. Colorado's high elevation ponds have recently observed a species range shift, traveling to higher altitudes than they have previously inhabited. The Mexican Cut Nature Preserve near the Rocky Mountain Biological Laboratory (RMBL) in Gothic, CO, is home to a prominent caddisfly Limnephilus externus, but recently a new range-shifting species, Nemotaulius hostilis, has appeared. Caddisflies play an essential role in nutrient cycling and putting energy back into the food web. The range-shifting species is known to excrete high rates of phosphorus …

The Effects Of Length And Increasing Nitrate Concentrations On Behavior Of Betta Splendens, Tess Hureau

Honors College

Nitrates are an important compound in nature. However, through a number of human activities, nitrate concentrations have exponentially increased in nature. Most of the anthropogenic nitrates come from fertilizers, sewage water, and other wastewater. These nitrates contaminate the water which can get into lakes, rivers, ponds, and other natural bodies of water. Betta splendens are a well studied species in the animal behavior community. They have defined and quantifiable displays and characteristics during aggressive and mating ritual behavior. Betta splendens live in freshwater habitats that have most likely come in contact with the increased levels of nitrates. This study observed …

Behavioral Effects Of Nitrate On Siamese Fighting Fish (Betta Splendens): Female Mate Preference And Anxiety, Courtney Stow

Honors College

In aquatic ecosystems, nitrate pollution due to anthropogenic activities has led to an increase in nitrate in water runoff and water resources. Nitrate is an essential component in the environment, especially for plant nutrients, but excess amounts can create water quality problems which can lead to serious consequences in humans and aquatic organisms. The effect of nitrate on organismal behavior is not well studied. The objective of this study was to examine how 96-h exposure to nitrate treatments (0, 10, 100ppm) modified female Betta splendens behavior, particularly mate preference for male color (e.g., red vs. blue males) and anxiety-like behavior. …

Dataset For: “Shifts In Habitat, Habitat Use, And Demography Of American Lobsters In Coastal Maine Over The Past Quarter Century.”, Robert Jarrett Ii, Damian Brady, Richard Wahle, Robert Steneck

Non-Thesis Student Work

This is the dataset for the manuscript "Shifts in habitat, habitat use, and demography of American lobsters in coastal Maine over the past quarter century." Our study revisited 20 long-term monitored sites at 10 m depth along more than 320 km of the Gulf of Maine. Sampling used quadrat sampling via scuba divers. We recorded fundamental changes in lobster habitat use and distribution. The data include count, size, sex, number of claws, and shelter use of lobster in addition to substrate type, percent cover of kelp and other macroalgae. The data are included in six .csv format files: (1) data …

Regeneration Response To Salvage Logging Following Tornado Disturbance, Colby K. Bosley-Smith

Electronic Theses and Dissertations

In an era of increasing natural disturbances, successful tree regeneration has grown more difficult to achieve. Salvage logging, a common management response to disturbance, may further impede regeneration success, although published literature currently remains inconclusive. In 2013, a rare tornado in northcentral Maine, USA, and subsequent salvage operation created three clear ‘treatments’ for evaluation of post-disturbance regeneration: blowdown, blowdown followed by salvage logging and an undisturbed control. In the summers of 2022 and 2023, (nine and ten) years post-tornado, we revisited this site to examine regeneration outcomes.

During the summer of 2022, we evaluated stand structure and regeneration success of …

Assessing The Role Of The Microbiome, Parasite Infections, And Movement In Avian Health, Olivia N. Choi

Electronic Theses and Dissertations

Avian health encompasses the physical, physiological, and behavioral well-being of birds. Assessing avian health is not only important for the conservation and management of wild birds and the recreational economy, but also for the management of infectious diseases that threaten public health and agriculture. Birds, comprising approximately 10,000 species and an estimated 50 billion individuals worldwide, are known to be involved in the spread of pathogens, some of which are zoonotic (from animals to humans), such as avian influenza and West Nile viruses. Individual measures of avian health may include physical measurements (e.g., body mass, wing length), pathogen infection status, …

Landings, Vol. 31, No. 12, Maine Lobstermen’S Community Alliance, Rebecca Nuzzi, Amber-Jean Nickel

Landings: News & Views from Maine's Lobstering Community

Landings content emphasizes science, history, resource sustainability, economic development, and human interest stories related to Maine's lobster industry. The newsletter emphasizes lobstering as a traditional, majority-European American lifeway with an economic and social heritage unique to the coast of Maine. The publication focuses how ongoing research to engage in sustainable, non-harmful, and non-wasteful commercial fishing practices benefit both the fishery and Maine's coastal legacy.

For more information, please visit the Maine Lobstermen’s Community Alliance (MLCA) website.

What Gives Me Hope, Heather M. Leslie

Maine Policy Review

The commentary focuses on the author's experiences over the last several years in Maine where she has conducted research, mentored students, and collaboratde with diverse community partners on a number of projects focused on shellfish fisheries co-management and other community-led resilience projects in coastal Maine.

Integrating Environmental Dna, Traditional Fisheries Techniques, And Species Distribution Modeling To Assess Bridle Shiner Status In Maine, Lara S. Katz

Electronic Theses and Dissertations

The bridle shiner (Notropis bifrenatus) is a small minnow species native to the eastern United States and southeastern Canada. The species is declining dramatically throughout most of its native range and has legal protection or concern status in thirteen states and two Canadian provinces. In Maine, the bridle shiner is listed as a Species of Special Concern and considered a Species of Greatest Conservation Need, partially because we lack a basic understanding of their status and distribution within the state. Bridle shiners have historically been found in southern and western Maine in densely vegetated, shallow habitats along the …

Climate Interactions Drive Tree Physiology And Growth In A Northeastern Forest Ecotone, Alexandra M. Barry

Electronic Theses and Dissertations

Climate change is a threat to global forest ecosystems. In the northeastern United States, forest trees are facing rising temperatures and increasingly inconsistent moisture regimes. In addition to long-term changes in climate conditions, there is concern about the potential for more frequent and intense climate extremes, which can have severe and rapid negative effects on tree physiology and growth. Further, climate extremes may co-occur to produce a greater magnitude of effect than the sum of their parts, with a prominent example being hot droughts, which are increasing in occurrence and severity. The impact of these and other extreme climate interactions …

Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson

Electronic Theses and Dissertations

Ecological restoration is an increasingly common practice across ecosystems, and current practices aim to restore the biological and physical processes underlying ecosystem function, often for the sake of endangered higher-level consumers. Studies of restoration outcomes often report few or inconsistent ecological changes, and monitoring of restoration projects rarely measures ecological processes. Monitoring also usually measures outcomes at a single scale, despite the prevalence of scale- dependent phenomena across ecosystems. My thesis uses measurements of ecological processes to assess restoration response and evaluates responses across multiple scales. I focus here on a long-term large wood addition project on the Narraguagus River …

Genetic Effects Of Anthropogenic Disturbance On Native Charrs, Brad Erdman

Electronic Theses and Dissertations

Artificial propagation has been utilized for over a century to offset anthropogenic declines of abundance for many fishes. Complex and poorly documented histories of habitat degradation and stockings have resulted in considerable uncertainty regarding whether contemporary populations are of native, hatchery, or mixed origins. This uncertainty is problematic as it precludes prioritizing the conservation of native populations that are postulated to possess local adaptations and greater evolutionary potential. Population genetics can assess the relative reproductive contributions of previous stocking events and in this dissertation I apply these methods to four empirical studies of native charr (genus Salvelinus) that have …

Comparative Energetics Of Mammalian Thermoregulatory Physiology, Ana M. Breit

Electronic Theses and Dissertations

Endothermy allows species to decouple body temperature from environmental
temperatures but does not equate to endothermic species maintaining those constant temperatures. Instead, heterothermy fluctuating body temperatures, both in and outside of torpor is common and allows endotherms to expand the limits of thermoneutrality. Thermolability is likely to be more common in the tropics and subtropics, where species live within or above their thermoneutral zone. My dissertation research focused on the heterothermic-homeothermic continuum, specifically quantifying where on the continuum different species fall at certain times and why those species have evolved to be at those points. I quantified the thermal profile …

Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson

Electronic Theses and Dissertations

The Gulf of Maine Distinct Population Segment of Atlantic Salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has prevented the extirpation of the species, but stocking methods represent tradeoffs between survival, domestication, and logistics. Egg planting, the use of eyed embryos, maximizes natural rearing opportunities which can be important for adaptation. This method, however, is logistically demanding and requires significant labor over large spatial, but short temporal, scales dictated by the ontogeny of the fish. However, the survival and dispersal behavior of Atlantic Salmon fry immediately after emergence from eggs planted in artificial nests …

Cross-Trophic-Level Dynamics In Aquatic Ecosystems And Their Application Across Ecological Contexts, Elliot M. Johnston

Electronic Theses and Dissertations

Cross-trophic-level dynamics represent biotic interactions between organisms in a food web that span two (e.g., predator-prey interactions) or more (e.g., bottom-up or top-down indirect interactions) trophic levels. These dynamics are fundamental to understanding a variety of animal attributes across ecological contexts, including life-history traits, population limitation, and resource management. A classic example illustrates how declines in sea otter (Enhydra lutris) populations had negative indirect effects on giant kelp (Macrocystis pyrifera) populations due to reduced top-down regulation of a primary kelp predator, purple sea urchin (Strongylocentrotus purpuratus). The need for management approaches that incorporate this food-web connectivity is evident in the …

I Ain't Afraid Of No Crab: Intertidal Gastropod Littorina Littorea Behavioral Response To Predation Risk By Carcinus Maenas, Isabelle Erin Smy

Honors College

Littorina littorea is an intertidal, invasive gastropod species common in the Gulf of Maine. In this paper, I studied the avoidance and risk-reducing behavioral responses of L. littorea to predation risk by invasive crustacean species Carcinus maenas. Avoidance and risk-reducing behavior in this study are defined by the tendency to move towards the edge and out of a simulated tide pool and the tendency to reduce feeding. The goal of this study was to determine whether the exposure to chemical cues of predators resulted in an increase in avoidance behavior, risk-reducing behavior, and a reduction in the time before the …

Comanagement In Maine: Integrating Fishermen’S Ecological Knowledge Into Government Oversight Of Fisheries, Anne Hayden

Maine Policy Review

Comanagement is the sharing of responsibility for management between fishermen and fisheries agencies. It shifts fishermen’s incentives to include longer term conservation goals, generates fine-scale information for management that would not otherwise be available, and develops fishing strategies that are consistent with conservation. Analysis of comanaged fisheries in Maine, for lobster, clams, river herring, and scallops, indicates that comanagement improves fisheries productivity and is more effective than standard, top-down, broad-scale fisheries management.

Why Is The Depletion Of Our Important Fish Stocks So Persistent?, James A. Wilson

Maine Policy Review

In the 1980s and 1990s, two events changed the fundamental structure of Maine's coastal ecology: inshore herring and then nearshore groundfish stocks were overfished and disappeared. Surprisingly, even without fishing, there has been no recovery. Standard fisheries management assumes that the recovery of any locally overfished place should be quick – fish from other places will 'fill in.'

In contrast, recent scientific work on social learning among animals suggests that fish have communication and learning abilities comparable to other vertebrates. Learning allows groups of fish to adapt to much more local places than possible if adaptation depended on genetics alone. …

Understanding The Impacts Of Anthropogenic Effects An Habitat Variability Interactions On Maine's Rocky Intertidal Ecosystem, Laura Braun

Electronic Theses and Dissertations

The rocky intertidal ecosystem is an important ecological and cultural aspect of the picturesque Maine coast, playing a vital role in not only Maine’s coastal ecosystem, but also to Maine’s economy. It’s distinct community structure along the sharp elevational gradient and the presence of daily stressors (wave action, heat, and desiccation), make the rocky intertidal ecosystem an important model ecosystem to monitor for effects from anthropogenic impacts. In this thesis, I describe attempts to monitor and understand the impacts of two of these anthropogenic impacts on this system: climate change and industrial harvesting of Ascophyllum nodosum along Maine’s coast. For …

Quantitative Silviculture Of Northern Conifers, David G. Ray

Electronic Theses and Dissertations

Quantitative tools used to guide the management of important northern conifer species require updating and refinement to address changes in the contemporary resource and evolving objectives of ownership. This work builds on an extensive body of knowledge about stand density management and innovates some new approaches. In sum, the three chapters presented herein: 1) seek to strengthen and more fully articulate arguments for adopting relative density as a primary metric of stand density assessment, 2) quantify minimum stand densities to achieve full site occupancy and argue for more parity with treatment of maximum stand density, and 3) present an empirically …

Carbon Dioxide Emissions From Deadwood In Forests Of The Northeastern United States, Zoe Read

Electronic Theses and Dissertations

As the climate changes, understanding the sources and sinks of greenhouse gases such as carbon dioxide (CO₂) is increasingly important. However, several components of the carbon cycle within forests remain poorly understood. For example, knowledge gaps exist in our understanding of CO₂ emissions from coarse woody material (CWM; logs and stumps), including how emissions change over time, how they are influenced by environmental variables, and how they compare to soil and ecosystem-level CO₂ emissions.

To fill these knowledge gaps, we examined CO₂ emissions from CWM at three sites. We sampled 18 red spruce (Picea …

A Sky Island Perspective: New England Alpine Plant Distributions Across The Region, Andrea Tirrell

Electronic Theses and Dissertations

Alpine ecosystems around the globe are at risk due to climate change, human disturbance, and habitat loss. New England alpine zones are small and fragmented, which could make them vulnerable to global change. However, the persistence of tundra relics throughout the Holocene suggests the persistence of these communities in microclimate refugia. Assessing the near-term vulnerability of alpine plant communities is challenged by a lack of standardized, repeat surveys and long-term monitoring data, which presents a challenge for the many agencies monitoring New England’s alpine zones. Island biogeography theory predicts that alpine species richness is a function of area, but this …

Assessing State Communication Of Resources And Education Effectiveness For Well Owners In Northern Maine: A Case Study, James Greenwood

Honors College

Private well water is an essential resource in the state of Maine, as over 38% of

the state’s population relies on it every day (Johnson et al. 2020). Unprotected by the provisions of the national Clean Water Act of 1974, which keeps public drinking water sources safe through regulation, well owners have to protect themselves against harmful environmental contaminants that threaten their water. However, as noted by research and leaders in the drinking water field, well owners generally have low well testing behaviors, leaving their safety up to fate. A common reason for this, as research as observed more than …

The Impact Of Glycine Betaine Applications On Drought Response In Wild Blueberries, Abigail Fisher

Honors College

Wild blueberries are an economically important crop for Maine, and with warming temperatures leading to increased periods of drought and increased soil moisture deficits, it is important to find new ways to combat the effects of drought. In this study, we aimed to look at the effect of foliar-applied glycine betaine applications on wild lowbush blueberries in both field and greenhouse experiments. The product being tested was Bluestim, a foliar-applied product containing >96% pure glycine betaine sold by Biobest. The product is claimed to work as an osmoprotectant allowing the plant to maintain turgor pressure and protect enzymes and macromolecules …

Ecological Implications Of Intraspecific Behavioral Variation In A Small Mammal Community, Allison Brehm

Electronic Theses and Dissertations

Variation among individuals is at the root of all evolution by means of natural selection. However, only in recent years has intraspecific behavioral variation been embraced as a potential driver of community and ecosystem processes, rather than considered statistical noise. Animal personalities, or behavioral differences between conspecifics that are consistent across time and contexts, are one such form of variation that has received considerable attention in the last two decades. Investigations of the ecological and ecosystem consequences of personality variation is at the current forefront of the field, but much work on this topic remains conceptual. Here, I apply large-scale …

3d Computer Modeling Offers New Insights Into Diatom Ecology, Joseph Mohan

Electronic Theses and Dissertations

Algae supply over half of the Earth’s global primary production and form the base of almost all aquatic food networks. Thus, changes in algal productivity or composition will induce profound shifts in many ecosystems. This research is guided by two questions. Herein I ask if 3D models of algae can be created accurately enough to use for research applications? If they can be accurately created, then how can these models be used to advance our understanding of functional trait evolution and paleoecology? Herein, I develop 3D computer models for estimating the volume of individual algae and their parts. I also …

Linkind Deadwood Inhabiting Fungi To Carbon Dioxide Flux Of Decomposing Coarse Woody Debris, Elyse Daub

Honors College

The decomposition of wood is driven by a combination of abiotic and biotic factors, the most influential of them all are fungi. These decomposer fungi use the wood for food, digesting woody material to absorb nutrients and release carbon dioxide. Fungi are the primary drivers of decomposition in most terrestrial ecosystems; thus, the rate and degree of decomposition are greatly dependent on the community of fungi found on woody debris. However, little is known about which fungi decompose woody debris most efficiently. This study aims to investigate the decomposer fungi in the Bear Brook Watershed via molecular techniques and quantify …