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A Genetic Based Approach To Management And Stocking Of Muskellunge, Douglas Zentner Jan 2015

A Genetic Based Approach To Management And Stocking Of Muskellunge, Douglas Zentner

Journal of Earth and Life Science

Fish stocking has long been used as a management tool among fisheries biologists and continues to be met with popular public opinion. Despite perceived simplicity, the full effects of stocking remain cryptic for many fish populations. Stocking has frequently been used to maintain or establish successful muskellunge (Esox masquinongy) populations. Coupled with other management practices the Minnesota Department of Natural Resources (MNDNR) has established Minnesota as a premier muskellunge fishery. From 1958 to 2012 the MNDNR stocked three strains of muskellunge in Big Mantrap Lake, MN. The first from Shoepack Lake, MN (hereafter Shoepack-strain) was used until the …


Why Do Caterpillars Whistle? Acoustic Mimicry Of Bird Alarm Calls In The Amorpha Juglandis Caterpillar, Jessica Lindsay Jan 2015

Why Do Caterpillars Whistle? Acoustic Mimicry Of Bird Alarm Calls In The Amorpha Juglandis Caterpillar, Jessica Lindsay

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Caterpillar species possess a range of anti-predator defenses, from regurgitation to sonar jamming. The North American walnut sphinx caterpillar (Amorpha juglandis) produces a variety of whistling noises when pinched. Limited observations indicate that this causes avian predators to retreat, leaving the caterpillar alone. However, it is unknown why this whistle is such an effective deterrent. Interestingly, the A. juglandis whistle is acoustically similar to the “seet” alarm call that many bird species produce in response to their own predators. We propose that the A. juglandis whistle is a form of acoustic mimicry, in which the caterpillar protects itself …


Investigating The Role Of Polyploidy In The Response Of Chamerion Angustifolium To Increased Soil Nitrogen Availability And Insect Herbivory, Alex Bales Jan 2015

Investigating The Role Of Polyploidy In The Response Of Chamerion Angustifolium To Increased Soil Nitrogen Availability And Insect Herbivory, Alex Bales

Dissertations, Master's Theses and Master's Reports

Human activities have more than doubled the input rate of nitrogen to terrestrial ecosystems. Increased soil nitrogen availability is associated with increased plant productivity, changes in plant resource allocation strategies, and changes in interactions between plants and their associated insect herbivores. For example, nitrogen-rich conditions can alter the physiological and chemical properties of plants in ways that increase their ability to deter herbivore attack (resistance) and maintain fitness following herbivore attack (tolerance). The ecological tolerance of plants to such abiotic and biotic environments is thought to be influenced by autopolyploidy, a commonly occurring phenomenon in plants in which individuals have …


Investigating Within-Canopy Variation Of Functional Traits And Cellular Structure Of Sugar Maple (Acer Saccharum) Leaves, Adam P. Coble Jan 2015

Investigating Within-Canopy Variation Of Functional Traits And Cellular Structure Of Sugar Maple (Acer Saccharum) Leaves, Adam P. Coble

Dissertations, Master's Theses and Master's Reports - Open

Patterns of increasing leaf mass per area (LMA), area-based leaf nitrogen (Narea), and carbon isotope composition (δ13C) with increasing height in the canopy have been attributed to light gradients or hydraulic limitation in tall trees. Theoretical optimal distributions of LMA and Narea that scale with light maximize canopy photosynthesis; however, sub-optimal distributions are often observed due to hydraulic constraints on leaf development. Using observational, experimental, and modeling approaches, we investigated the response of leaf functional traits (LMA, density, thickness, and leaf nitrogen), leaf carbon isotope composition (δ13C), and cellular structure to light availability, height, and leaf water …


Translocation And Telemetry Tracking Of Lake Sturgeon In The Menominee River, Mi / Wi, Jeremy G. Olach Jan 2015

Translocation And Telemetry Tracking Of Lake Sturgeon In The Menominee River, Mi / Wi, Jeremy G. Olach

Dissertations, Master's Theses and Master's Reports - Open

The Menominee River is a Michigan-Wisconsin boundary water historically traversed by lake sturgeon (Acipenser fulvescens), but now contains fragmented populations between hydroelectric dams. Though fish passage is currently being implemented on the lower dams, it is unclear whether sturgeon given access to historic spawning grounds would use them. In 2012 and 2013, a total of 15 pre-spawning sturgeon were captured, implanted with sonic transmitters and translocated upstream over two hydroelectric dams to the stretch below the historic spawning site of Sturgeon Falls. Sturgeon were then tracked via five stationary receivers from April 2012 until August 2013, and with …


Biogeochemical Cycling In Lake Superior Tributaries: Seasonality, Quantity And Quality Of Export, Ashley Anne Coble Jan 2015

Biogeochemical Cycling In Lake Superior Tributaries: Seasonality, Quantity And Quality Of Export, Ashley Anne Coble

Dissertations, Master's Theses and Master's Reports - Open

Seasonal and spatial variability in environmental factors may affect dissolved organic matter composition and nutrient transformation and retention in streams. The objective of this research was to quantify and describe seasonality, quantity, and quality of nutrient processing and export of ammonium (NH4), soluble reactive phosphate (SRP), and dissolved organic carbon (DOC) into Lake Superior through intensive study in a small 1st order watershed coupled with snapshot measurements across 12 tributaries that varied in size, location, and wetland coverage. Our results suggest biodegradable C is exported from a small headwater stream year-round and that DOC mineralization rates can be …


Oviposition Site Selection By Mosquitoes: Predator-Released Kairomones And Responses To Different Taxa, Lauren Larea Eveland Jan 2015

Oviposition Site Selection By Mosquitoes: Predator-Released Kairomones And Responses To Different Taxa, Lauren Larea Eveland

Electronic Theses and Dissertations

Oviposition site selection is a critical reproductive behavior for egg-laying organisms that offer little to no parental care. Determining the mechanisms females use to assess sites is critical to understanding life history traits, community structure, and species interactions. Mosquitoes are excellent model organisms for studying oviposition site selection for numerous reasons: 1) a poor decision can lead to zero reproductive success, 2) females actively assess and choose among habitat patches when locating an oviposition site, 3) larvae remain in the habitat where they hatch until they metamorphose, and 4) they lay conspicuous egg rafts that allow direct assessment of oviposition. …


The Effects Of Substrate Roughness In Air And Water On The Gecko Adhesive System, Amanda Palecek Jan 2015

The Effects Of Substrate Roughness In Air And Water On The Gecko Adhesive System, Amanda Palecek

Williams Honors College, Honors Research Projects

In an effort to better understand the fascinating gecko adhesive system, scientists have long tested the abilities of the gecko in controlled conditions that mimic the gecko’s native environment. The effects of humidity, environmental temperature, and exposure to water have all been tested. Roughness, however has not been studied in great detail. Surfaces of varying roughnesses are all over the gecko’s natural environment. We tested geckos on hydrophilic silicon carbide sandpapers of varying roughnesses in both air and water to attempt to better study the effects of roughness on gecko adhesion. When tested on the rougher (1 µm) surface, the …


Behavior Of Pollinators That Share Two Co-Flowering Wetland Plant Species, Joshua R. Morris Jan 2015

Behavior Of Pollinators That Share Two Co-Flowering Wetland Plant Species, Joshua R. Morris

Williams Honors College, Honors Research Projects

Abstract:

Intermixed, co-flowering plant species often attract the same pollinators and may therefore compete for pollinator visits. Mimulus ringens and Verbena hastata are sympatric wetland plants that flower in synchrony and share many pollinators, the most common being bumblebees. The possibility of competition between these two plant species led to this observational study tracking pollinator movements in an area intermixed with both M. ringens and V. hastata. We identified pollinator species and tracked them as they visited flowers and moved from plant to plant. Smaller bees seemed to prefer the smaller flowers present on the V. hastata, and …


Are Land-Use Changes Reflected In Diets Of Mourning Doves (Zenaida Macroura) In Eastern South Dakota, Joshua B. Smith, Troy Grovenburg, Matthew A. Perrion, Jason M. Augspurger, Trevor W. Bultje, Anna M. Robinson, Brandi L. Crider, Datta Shubham, Jonathan A. Jenks Jan 2015

Are Land-Use Changes Reflected In Diets Of Mourning Doves (Zenaida Macroura) In Eastern South Dakota, Joshua B. Smith, Troy Grovenburg, Matthew A. Perrion, Jason M. Augspurger, Trevor W. Bultje, Anna M. Robinson, Brandi L. Crider, Datta Shubham, Jonathan A. Jenks

Natural Resource Management Faculty Publications

Food habits of the mourning dove (Zenaida macroura) have been extensively studied in the southern United States (McClure 1943, Korschgen 1958, Carpenter 1971) and consist primarily of vegetable matter throughout their range (Beckwith 1959). Diet studies in several states have indicated agricultural crops, specifically corn and wheat, were the most readily consumed plant seeds (Korshgen 1958, Carpenter 1971). Similarities observed in diets of doves were dependent on the agricultural crops available within the area. For example, in Missouri, some seasonal variability was documented suggesting doves forage based on food availability as much as by food preference (Korschgen 1958). However, in …


Assessing Changes In Avian Communities, Jessie D. Golding Jan 2015

Assessing Changes In Avian Communities, Jessie D. Golding

Graduate Student Theses, Dissertations, & Professional Papers

Grazing is a potentially powerful tool to address wildlife declines associated with land use conversion in the western United States. Grazing systems can be manipulated to achieve desired vegetation outcomes, preserve native habitat and economically benefit multiple stakeholders. As a result, systems designed to benefit native ecosystems are being widely implemented. However, the benefits of these grazing systems on many wildlife communities remain relatively unexplored. Songbirds provide an ideal study system to test these benefits because they continue to use native habitat that is currently grazed. Given limited time and resources, conservation practitioners often monitor a single focal species or …


Assessing The Permeability Of Landscape Features To Animal Movement: Using Genetic Structure To Infer Functional Connectivity, Sarah J. Anderson, Elizabeth M. Kierepka, Robert K. Swihart, Emily K. Latch Jan 2015

Assessing The Permeability Of Landscape Features To Animal Movement: Using Genetic Structure To Infer Functional Connectivity, Sarah J. Anderson, Elizabeth M. Kierepka, Robert K. Swihart, Emily K. Latch

Department of Forestry & Natural Resources Faculty Publications

Human-altered environments often challenge native species with a complex spatial distribution of resources. Hostile landscape features can inhibit animal movement (i.e., genetic exchange), while other landscape attributes facilitate gene flow. The genetic attributes of organisms inhabiting such complex environments can reveal the legacy of their movements through the landscape. Thus, by evaluating landscape attributes within the context of genetic connectivity of organisms within the landscape, we can elucidate how a species has coped with the enhanced complexity of human altered environments. In this research, we utilized genetic data from eastern chipmunks (Tamias striatus ) in conjunction with spatially explicit habitat …


Ecology/ Graduate Students/ Westra & Walton/ University Of Oregon/ 2012, Brian Westra, Dean Walton Jan 2015

Ecology/ Graduate Students/ Westra & Walton/ University Of Oregon/ 2012, Brian Westra, Dean Walton

Data Information Literacy Case Study Directory

The case study covers a one-shot seminar style Data Information Literacy program offered to graduate students associated with an NSF funded Ecology project. Topics covered included file formats, publishing data, metadata, preservation and data citation. Materials include a book chapter describing the case study, the lesson plan for the session and the evaluation form used to gather feedback.


Unraveling The Genetic Mechanisms Involved In The Evolution And Development Of The Thoracic Appendages In Insects, Victor Medved Jan 2015

Unraveling The Genetic Mechanisms Involved In The Evolution And Development Of The Thoracic Appendages In Insects, Victor Medved

Wayne State University Dissertations

Insects display the greatest amount of structural and functional variation among animal groups, particularly in regard to their appendage morphology. These differences can range from the diverse pigmentation patterns between fore- and hindwings to changes in the size and shape of legs. The greatly enlarged jumping hind leg in crickets and grasshoppers is one of the best known illustrations of such diversity, representing a unique feature for the entire order of these insects (Orthoptera). Previous work from our lab has shown that the homeotic gene Ultrabithorax (Ubx) plays a key role in the enlargement of hind legs not only in …


Population Differentiation And Habitat Selection Of A Montane Red Fox Population In The Greater Yellowstone Ecosystem, Patrick Cross Jan 2015

Population Differentiation And Habitat Selection Of A Montane Red Fox Population In The Greater Yellowstone Ecosystem, Patrick Cross

Graduate Student Theses, Dissertations, & Professional Papers

Montane red fox (Vulpes vulpes) populations across the western United States are genetically and morphologically distinct from foxes at lower elevations. These montane populations also share a preference for subalpine forest habitats. One hypothesis is that they stem from boreal forest-associated ancestors that expanded during the Pleistocene when boreal forests extended farther south than they do today. Forest habitat selection may therefore aid the persistence of native populations surrounded by non-native conspecifics. Alternatively, this behavior may be an avoidance mechanism in response to competition with larger coyotes (Canis latrans), or a product of the fox's natural adaptability. The red fox …


Reproductive Biology Of Syntopic Blackside Dace And Southern Redbelly Dace In Two Kentucky Streams, Brajaan Hayes Jan 2015

Reproductive Biology Of Syntopic Blackside Dace And Southern Redbelly Dace In Two Kentucky Streams, Brajaan Hayes

Online Theses and Dissertations

When a rare endemic species and an ecologically similar, but more cosmopolitan species share habitat, understanding how they interact with each other is important for conservation efforts. This is especially true if both species rely on the same spawning habitat, which could potentially lead to competitive displacement or hybridization. It is known that the federally threatened Blackside Dace and common Southern Redbelly Dace are ecologically similar species, occur syntopically in Kentucky in the upper Cumberland River basin, and utilize some of the same host species for nest sites; however, it is unclear if the two fish species are spawning site …


Effects Of Supplemental Food On The Behavior, Aggression, And Paternity Status Of Male Indigo Buntings (Passerina Cyanea), Bradley Mcleod Jan 2015

Effects Of Supplemental Food On The Behavior, Aggression, And Paternity Status Of Male Indigo Buntings (Passerina Cyanea), Bradley Mcleod

Online Theses and Dissertations

Breeding is an energetically costly activity for birds. If energy-limited, birds may alter their time budgets, reducing time spent in some activities and spending more time in others. To date, no experimental study has investigated the possible effect of food availability on male mate guarding behavior. Additionally, previous results from food supplementation studies are mixed. My objectives were to determine how food supplementation might influence the breeding behavior of male Indigo Buntings (Passerina cyanea). I predicted that, compared to non-supplemented males, food-supplemented males would: 1) spend less time foraging, 2) spend more time singing, 3) spend more time mate guarding, …


Flight Vocalizations And Displays Of Adult Chimney Swifts (Chaetura Pelagica): Description And Function, Louise Ann Peppe Jan 2015

Flight Vocalizations And Displays Of Adult Chimney Swifts (Chaetura Pelagica): Description And Function, Louise Ann Peppe

Online Theses and Dissertations

The vocalizations of many songbirds have been well documented and analyzed, but less is known about the vocal behavior of many non-passerines, including swifts. While flying alone as well as during aerial displays with conspecifics, Chimney Swifts (Chaetura pelagica) often utter a twitter call consisting of a series of high-frequency chip notes. However, little is known about the possible function(s) of swift flight displays and their twitter call. My objectives were to record, analyze, and document the aerial behaviors and associated vocalizations of adult Chimney Swifts. I studied swifts at the Blue Grass Army Depot in Madison County, Kentucky, where …


Fate Of Captive-Reared Bobwhite Quail Released In Central Kentucky, Adam Carter Jan 2015

Fate Of Captive-Reared Bobwhite Quail Released In Central Kentucky, Adam Carter

Online Theses and Dissertations

The fate of pen-raised bobwhite quail (Colinus virginianus) released onto two farms (Site 1 and 2) and a reclaimed coal surface mine (Site 3) in south-central Kentucky during the summers of 2008 and 2009 was assessed. Of the 57 bobwhite quail radio-tagged and released in this study, the fate of 26 (45%) was unknown because the telemetry signal was lost and the birds could not be located. Within 34 days after release, mortality of the remaining 31 radio-tagged birds was 100%. Raptors, coyotes, and mesomammal predators were responsible for most (84%) of the identified quail mortality; accounting for the deaths …


Offspring Retrieval Behaviors After Brood Loss In The Convict Cichlid, Heather Witherspoon Govert Jan 2015

Offspring Retrieval Behaviors After Brood Loss In The Convict Cichlid, Heather Witherspoon Govert

Online Theses and Dissertations

Parents provide care for their young in several different ways. One of these is searching for and retrieving any young that may become displaced from their nest. In monogamous biparental species, parents may share care of their young, including retrieval efforts. Convict cichlids (Amatitlania siquia) are an example of a monogamous biparental fish that show shared parental care of young. In the wild, these cichlids defend nests and search for missing young in response to complete or catastrophic brood loss. This retrieval behavior is important for both parents because parents, especially the males, have been observed to abandon their mate …


Vegetation-Based Metrics Of Biotic Integrity For Assessing The Ecological Condition Of Wetlands Of Kentucky, Tanner Matthew Morris Jan 2015

Vegetation-Based Metrics Of Biotic Integrity For Assessing The Ecological Condition Of Wetlands Of Kentucky, Tanner Matthew Morris

Online Theses and Dissertations

Over the last two centuries, wetland acreage across the world has significantly declined due to human disturbances. It has been estimated that Kentucky has lost over 80% of its wetland area. In response to these losses occurring across the United States, the Clean Water Act was passed to halt this dramatic decline and to restore the ecological integrity of waters of the United States. To enforce the Clean Water Act, a number of ecological assessment techniques have been developed to quantify the ecological quality of the waters of the United States. Kentucky recently adopted a rapid method for assessing the …


Validating A Kentucky Wetland Rapid Assessment Method For Forested Riverine Wetlands Using Vegetation, Bird Surveys, And Landscape Analysis, Johnryan Andrew Polascik Jan 2015

Validating A Kentucky Wetland Rapid Assessment Method For Forested Riverine Wetlands Using Vegetation, Bird Surveys, And Landscape Analysis, Johnryan Andrew Polascik

Online Theses and Dissertations

Within the last two centuries, Kentucky has undergone wetland losses exceeding 80 percent (approximately 500,000 hectares). As a response to these losses, the Kentucky Division of Water (KDOW) and Eastern Kentucky University (EKU) developed the Kentucky Wetland Rapid Assessment Method (KY-WRAM) to evaluate the condition of Kentucky's remaining wetlands. The goal of this study was to validate the KY-WRAM for forested riverine wetlands using a vegetation index of biotic integrity (VIBI), bird surveys, and landscape development index (LDI). Specific objectives of this study were to: 1) determine the correlation between bird species richness, VIBI, and LDI with the KY-WRAM in …


Effect Of Variation In Nestling Hunger Levels On The Begging Behavior Of Nestlings And The Provisioning Behavior Of Adult American Kestrels, Katheryn Ann Watson Jan 2015

Effect Of Variation In Nestling Hunger Levels On The Begging Behavior Of Nestlings And The Provisioning Behavior Of Adult American Kestrels, Katheryn Ann Watson

Online Theses and Dissertations

Little is known about how variation in nestling begging intensity influences the behavior of adult raptors and how responses of adult males and females to such variation might differ. My objective was to manipulate the begging intensity of nestling American Kestrels (Falco sparverius) and examine the responses of adult males and females. I studied 12 pairs of kestrels nesting in nest boxes from 1 March to 1 July 2014 at the Blue Grass Army Depot, Madison County, Kentucky. Nest boxes were modified with a separate compartment for a camcorder to record nestling behavior, and a second camcorder was placed outside …


Distribution, Movement, And Ecology Of Etheostoma Spilotum (Gilbert), The Kentucky Arrow Darter, In Gilberts Big Creek And Elisha Creek, Red Bird River Basin, Clay And Leslie Counties, Kentucky, Jonathan Bradley Baxter Jan 2015

Distribution, Movement, And Ecology Of Etheostoma Spilotum (Gilbert), The Kentucky Arrow Darter, In Gilberts Big Creek And Elisha Creek, Red Bird River Basin, Clay And Leslie Counties, Kentucky, Jonathan Bradley Baxter

Online Theses and Dissertations

The Kentucky Arrow Darter (KAD), Etheostoma spilotum, is an endemic species to the Upper Kentucky River Basin and is currently proposed for listing as threatened under the Endangered Species Act. The ecology and population status of this benthic species is poorly understood, so this study was designed to investigate the species’ movement capabilities, population dynamics, and overall ecology in two streams (Gilberts Big and Elisha Creek) in the Red Bird Ranger District, Daniel Boone National Forest, Kentucky. Project objectives included quantification of movement patterns, identification of microhabitat use, and estimation of population size in both streams. Sampling was conducted during …


Examining The Impacts Of Valley Fills In Stream Ecosystems On Amphibian And Aquatic Insect Communities In Southeastern Kentucky, John Clayton Bourne Jan 2015

Examining The Impacts Of Valley Fills In Stream Ecosystems On Amphibian And Aquatic Insect Communities In Southeastern Kentucky, John Clayton Bourne

Online Theses and Dissertations

Chapter 1. Abstract: Biodiversity is not evenly distributed, and understanding factors that determine spatial patterns of species diversity remains a key question in ecology. Because of their relatively high abundance and complex life cycles, stream salamanders and aquatic insects are important trophic links and serve a critical role in transferring energy. Despite this importance little research has examined their community structure simultaneously in aquatic ecosystems. The primary objective of this research was to determine the structure of these communities across natural areas of southeastern Kentucky and understand what factors impact their abundances and distributions. To address this, we sampled eight …


Wolf-Cougar Co-Occurrence In The Central Canadian Rocky Mountains, Ellen Brandell Jan 2015

Wolf-Cougar Co-Occurrence In The Central Canadian Rocky Mountains, Ellen Brandell

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Cougars and wolves are top carnivores that influence the dynamics of an ecosystem, including prey behavior and dynamics, and interspecific competition. Studies about the interactions between wolves and cougars typically find wolves are dominant competitors to cougars. We examined single-species, single-season occupancy models and co-occurrence models of wolves and cougars in the Central Canadian Rocky Mountains to understand interactions between these two species on a grand landscape. Data was collected from 2012-2013 using remote wildlife cameras and separated into seasons. Naïve occupancy estimates were larger for wolves in both seasons, but both species had smaller ranges in winter. There were …


Space Use By Resident And Transient Coyotes In An Urban–Rural Landscape Mosaic, N. Mitchell, M. W. Strohbach, R. Pratt, W. C. Finn, Eric G. Strauss Jan 2015

Space Use By Resident And Transient Coyotes In An Urban–Rural Landscape Mosaic, N. Mitchell, M. W. Strohbach, R. Pratt, W. C. Finn, Eric G. Strauss

Center for Urban Resilience Scholarship

Context. Coyotes (Canis latrans) have adapted successfully to human landscape alteration in the past 150 years and in recent decades have successfully moved into urban areas. While this causes concern about human–wildlife conflicts, research also suggests that coyotes tend to avoid humans and human activity in urban areas. For improving management, a better understanding of space use by coyotes is needed.

Aims. To study how coyote social behaviour influences fine-scale space use in urban areas we present results from an extensive, multi-year GPS telemetry study (2005–13). The study area in coastal Rhode Island is a mosaic of rural, …


The Export Of An Algal Toxin Into Terrestrial Predators Via Emerging Aquatic Insects, Nicholas J. Moy Jan 2015

The Export Of An Algal Toxin Into Terrestrial Predators Via Emerging Aquatic Insects, Nicholas J. Moy

Theses and Dissertations

Algal blooms are directly related to human-caused nutrient enrichment of water bodies. The cyanobacteria Microcystis aeruginosa produces microcystin (MC), a toxin that has been linked with mortalities and illness of many organisms. We show that MC is not constrained by the aquatic-terrestrial ecotone. MC was detected in a primary consumer and emerging aquatic invertebrate (Hexagenia Mayfly), a terrestrial insect and predator of emerging aquatic invertebrates (Tetragnathidae Spider), and a vertebrate consumer (Prothonotary Warbler). Mayfly and spider MC levels varied across the blooming period. MC levels in prothonotary warbler livers varied by age class; nestlings having the highest levels. MC levels …


Observations Of Hippopotamus H. Amphibius In The Little Scarcies River Of Sierra Leone And Arguments For Their Conservation Based On Roles They Play In Riverine Grasslands And Nutrient Loading, Lindsey R. Perry Jan 2015

Observations Of Hippopotamus H. Amphibius In The Little Scarcies River Of Sierra Leone And Arguments For Their Conservation Based On Roles They Play In Riverine Grasslands And Nutrient Loading, Lindsey R. Perry

Dissertations, Master's Theses and Master's Reports

A small population of Hippopotamus amphibius remains in Sierra Leone and conservation efforts may be needed to support the Hippos and their indirect benefits to fisheries and grassland production. The hippo is a known ecosystem engineer, and a potentially important contributor of nutrients to the river systems they inhabit supporting the food web and local fisheries. In this study I observed hippos in the Little Scarcies River and uplands of the Outamba-Kilimi National Park to estimate their numbers and ultimately their potential input of nutrients into the river. Hippos forage at night in grasslands neighboring rivers, removing up to 3.62 …


Context-Dependent Individual Variation In Foraging Behaviour And Parental Care In House Sparrows, David Moldoff Jan 2015

Context-Dependent Individual Variation In Foraging Behaviour And Parental Care In House Sparrows, David Moldoff

Theses and Dissertations--Biology

Behaviors can exhibit a wide degree of plasticity depending on the environmental context in which they are expressed. Despite this, repeatable differences have been found among and within individuals across a wide range of taxa. For my thesis, I investigated individual differences in foraging and parental care. In the first experiment, I assessed house sparrows (Passer domesticus) for domain-generality among neophobia, habituation and associative learning as they are all responses to novelty. While the results of the study find individual differences in each of these contexts the conclusion supported separate mechanisms for each response (domain-specificity). In the second experiment, I …