Animal Sciences Commons^™

Spatio-Temporal Dynamics Of Atlantic Cod Bycatch In The Maine Lobster Fishery And Its Impacts On Stock Assessment, Robert E. Boenish

Electronic Theses and Dissertations

Of the most iconic fish species in the world, the Atlantic cod (Gadus morhua, hereafter, cod) has been a mainstay in the North Atlantic for centuries. While many global fish stocks have received increased pressure with the advent of new, more efficient fishing technology in the mid-20^th century, exceptional pressure has been placed on this prized gadoid. Bycatch, or the unintended catch of organisms, is one of the biggest global fisheries issues. Directly resulting from the failed recovery of cod in the GoM, attention has been placed as to possible sources of unaccounted catch. Among the most …

The Effects Of Habitat And Connectivity On Tropical Ant Ecology And Behavior., Benjamin Jacob Adams

Electronic Theses and Dissertations

This dissertation explores the role that physical connections among and within habitats play in determining the local diversity and behaviors of cursorial organisms. Understanding the processes that regulate local community assembly and that contribute to the maintenance of species diversity is a cornerstone of community ecology. Ants are a useful model for studies of local communities because they are abundant and fulfill a variety of ecological roles. Chapter one of the dissertation examines the how lianas (woody vines) function as connective structures among tree crowns and how these connections affect arboreal ant community structure within a tropical forest canopy. Trees …

Origins Of Animal Cell Adhesion, Jennyfer Mora Mitchell

Electronic Theses and Dissertations

A fundamental requirement for multicellularity is cell adhesion. This includes mechanisms by which cells adhere to each other and to their secreted extracellular matrix (ECM). Two well characterized adhesion complexes in animals include: 1) adherens junctions (AJs), which are involved in cell-cell adhesion and composed of cadherin receptors, p120-, α- and β-catenin, and 2) focal adhesions (FAs), which are involved in cell-ECM adhesion and include proteins such as integrins, vinculin, paxillin, talin and focal adhesion kinase (FAK). The molecular components of AJs are widely conserved in animals, and largely absent in non-animals. In contrast, the molecular components of FAs have …

Aspects Of White-Tailed Deer Ecology And Management: Effects Of Imidacloprid And An Evaluation Of Management At Great Swamp National Wildlife Refuge, Elise Hughes Berheim

Electronic Theses and Dissertations

White-tail deer (Odocoileus virginianus) are an economically and recreationally important species throughout their range, and understanding their ecology to implement beneficial management techniques is invaluable. This thesis focused on two studies 1) the effect of Imidacloprid on adult female and fawn physiology and 2) an evaluation of techniques to monitor white-tailed deer at Great Swamp National Wildlife Refuge (GSNWR). Imidacloprid, a widely-used pesticide, has been linked to lethal and sub-lethal effects in insects and small vertebrates, however, no research has been conducted on white-tailed deer. Twenty captive pregnant adult female and subsequent fawns housed at the South Dakota …

Breeding Ecology And Habitat Use Of Unisexual Salamanders And Their Sperm-Hosts, Blue-Spotted Salamanders (Ambystoma Laterale), Kristine Hoffmann

Electronic Theses and Dissertations

Unsexual Salamanders within the Blue-Spotted Salamander Complex carry combinations of ambystomatid genomes (those of Blue-Spotted Salamanders, Ambystoma laterale, and Jefferson Salamanders, A. jeffersonianum in Maine). They are nearly all female, breed in wetlands, and use sperm of related species to reproduce. Little is known about their ecology to guide the conservation of this unique lineage. I examined breeding site occupancy, demographics, orientation, and terrestrial habitat selection of Unisexual Salamanders in comparison to Blue-Spotted Salamanders and other amphibians. I compared statistical tests of orientation to determine which was most appropriate for pitfall data.

Unisexual Salamander occupancy at breeding sites was positively …

The Biogeographic Origins And Trophic Ecology Of Maine’S Island Red-Backed Salamanders (Plethodon Cinereus), Nikko-Ideen Shaidani

Electronic Theses and Dissertations

Island populations of terrestrial species have an increased potential, compared to mainland populations, to adapt and diverge, as these populations often are isolated with respect to gene flow from other populations and may be subjected to novel pressures. Indeed, extended isolation of individuals can elicit dramatic changes within populations and is recognized as a common driver of speciation. It is for these reasons that island populations are often a priority for conservation. Plethodontid salamanders are among the most terrestrial of Maine’s amphibians and are not tolerant of prolonged exposure to seawater, and yet, they are found on a number of …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

Late Quaternary Dragon Lizards (Agamidae: Squamata) From Western Australia, Julie Rej

Electronic Theses and Dissertations

Fossil Agamidae from Western Australia have been the subject of limited study. To aid in fossil agamid identification, Hocknull (2002) examined the maxilla and dentary of several extant species from Australia and determined diagnostic characters for various species groups. In the study here, fossil agamids from two localities in Western Australia, Hastings Cave and Horseshoe Cave, were examined, grouped, and identified to the lowest unambiguous taxonomic level. Morphometric analyses were conducted to compare morphotypes, and find additional diagnostic characters. From Hastings Cave there were two maxilla morphotypes and three dentary morphotypes. Based on identifications, taxa present at this locality were …

Understanding The Impact Of Commercial Harvest On White Suckers (Catostomus Commersonii) In Maine, Megan A. Begley

Electronic Theses and Dissertations

The State of Maine issues an unlimited number of commercial permits for the harvest of White Suckers Catostomus commersonii in Maine’s inland waters. The fishery provides a necessary source of fresh lobster Homarus americanus bait to coastal communities at a time when other bait sources are scarce. The impacts of the increasing number of permits and subsequent numbers of fishermen on the white sucker population is unknown. The Maine Department on Inland Fisheries and Wildlife (MDIFW) has closed a number of waters due to concerns that overfishing and incidental catch of other fish species may occur.

In Chapter 1, we …

Behavioral Ecology Of Landbird Migrants In A Complex And Changing Flyway System: The Gulf Of Maine, Adrienne J. Leppold

Electronic Theses and Dissertations

In and around the Gulf of Maine, over 300 species of birds have been documented during migration, and tens of millions of songbirds may pass through the region on a single autumn night. Shorelines are widely documented as major migration corridors. There is ample evidence that coastal areas concentrate migrants and many species make overwater movements to and from breeding and wintering grounds. Data collected from radar, banding, and ceilometry studies in the northeast have provided us with evidence that birds migrate along the coast and make overwater movements across the Gulf of Maine and Bay of Fundy during both …

Description Of Cranial Elements And Ontogenetic Change Within Tropidolaemus Wagleri (Serpentes: Crotalinae)., Nicolette L. Hill

Electronic Theses and Dissertations

Tropidolaemus wagleri is a species of Asian pitviper with a geographic range including Thailand, Vietnam, Malaysia, Singapore, Bruniei, parts of Indonesia, and the hilippines. Tropidolaemus is a member of the Crotalinae subfamily, within Viperidae. The genus Tropidolaemus includes five species, and was once included within the genus Trimeresurus. While some osteologic characteristics have been noted a comprehensive description of cranial elements has not been produced for T. wagleri. An in-depth description of the cranial skeleton of Tropidolaemus wagleri lays the foundation for future projects to compare and contrast other taxa within Crotalinae and Viperidae. The chosen reference specimen …

Sources Of Ecologically Important Trait Variation In Mosquitofish (Gambusia Affinis And Gambusia Holbrooki), Heather Ann Arnett

Electronic Theses and Dissertations

The study of contemporary evolution and eco-evolutionary dynamics is classically defined in terms of genetic evolution, but the actual suite of processes driving contemporary trait change is likely much more complex than often credited. This dissertation considers additional mechanisms of trait change that might be important to an emerging model system for study of contemporary evolution and eco-evolutionary dynamics. Specifically, the research focuses on phenotypically plastic and demographic trait variation in Eastern and Western Mosquitofish (Gambusia affinis and G. holbrooki) facing the major ecological gradient of predation risk. Plasticity experiments employed a common-garden rearing design to manipulate fish …

Evaluation Of Bobcat (Lynx Rufus) Survival, Harvest, And Population Size In The West-Central Region Of South Dakota, Brandon M. Tycz

Electronic Theses and Dissertations

Recent concern regarding bobcat (Lynx rufus) population status has prompted researchers and managers to gather additional information about bobcats in South Dakota. From 2012–2015, we assessed population dynamics of bobcats occupying the west-central region of South Dakota. Our objectives were to: 1) estimate annual survival rates; 2) determine cause-specific mortality; 3) estimate a population size for the western prairie region of South Dakota; 4) estimate home range size of individually marked bobcats; 5) evaluate reproductive status; and 6) build a population model. We captured and radio-collared 51 (24 male, 27 female) bobcats with VHF collars. Annual survival was 65.1% (95% …

Evaluation Of Bison (Bison Bison) Ecology At The Olson’S Bison Conservation Ranches, Pine River Ranch, Manitoba, Canada, Joshua L. Leonard

Electronic Theses and Dissertations

Bison (Bison bison), the largest mammalian species in North America, historically numbering in the tens of millions (Roe 1970, McHugh 1972, Dary 1989, Shaw 1995), was nearly extirpated at the turn of the 19th century (Knapp et al. 1999; Gates et al. 2010). At the time, estimates of less than 1,000 bison remaining in North America are widely accepted (Hornaday 1889; Seton 1927; Gates et al. 2010). The decline of bison includes factors such as disease (Flores 1991; Isenberg 2000), sport hunting (Danz 1997; Dary 1989; Hewitt 1919; Isenberg 2000; McHugh 1972), and unofficially funded commercial hunting by the U.S. …

Effects Of Melatonin On Heartbeat And Possible Identification Of A Melatonin Receptor In Drosophila Melanogaster, Tricia L. Vankirk

Electronic Theses and Dissertations

Chapter 1 of this manuscript is a literature review that serves as an introduction to the entire dissertation. Chapter 2 examines the effects of the melatonin injection on heart rate and rhythmicity in Drosophila melanogaster Canton-S (wild-type) pupae and pupae bearing a variety of heart mutations. Chapter 3 investigates further the possible mechanisms of melatonin’s ability to increase heart rhythmicity without significantly affecting heart rate. A melatonin antagonist, luzindole; a high-affinity melatonin agonist, 2-iodomelatonin and RNAi techniques are used to identify a possible melatonin receptor in Drosophila melanogaster.

An appendix contains a previously published manuscript detailing experiments performed at the …

A Systematic Review Of The Soricimorph Eulipotyphla (Soricidae: Mammalia) From The Gray Fossil Site (Hemphillian), Tennessee, Joshua Doby

Electronic Theses and Dissertations

Due in part to the incompleteness of the Cenozoic fossil record in the eastern U.S., the evolution and immigration of shrews (Soricidae) is not well understood. A rich soricid fauna from the Gray Fossil Site (GFS), Washington County, TN, has enabled many new inferences to be made. There are 7 new species in 6 genera: Paenelimnoecus, “Blarinella”, Petenyia, Tregosorex, Crusafontina, and Gen et sp. nov. GFS species of the genera Paenelimnoecus, “Blarinella”, and Petenyia are the first occurrence of each genus in the New World. Tregosorex, Crusafontina, and the N.A. taxon Limnoecus all have their latest documented occurrence at the …

Earthworm, Microbial Biomass, And Leaf Litter Decay Responses After Invasive Honeysuckle Shrub Removal From Urban Woodlands., Robert Preston Pipal

Electronic Theses and Dissertations

Invasive species are one of the leading causes of biodiversity loss and their presence can significantly impact the structure and function of native ecosystems. In this dissertation, the impacts of the invasive honeysuckle shrub, Lonicera maackii, on exotic earthworm populations, leaf litter decay responses, and inorganic and organic nutrient pools in an urban woodland park are assessed. Chapter 1 provides a brief review of honeysuckle's effects on forest ecosystems. Chapter 2 describes honeysuckle’s effects on exotic earthworm populations and the seasonal importance of macroinvertebrates to leaf litter decomposition in urban woodlands. This study revealed that L. maackii promoted higher exotic …

Determinants Of Bite Force In Four Species Of Sharks From The Gulf Of Mexico With An Emphasis On The Atlantic Sharpnose Shark, Rhizoprionodon Terraenovae, Kyle Walter Rice

Electronic Theses and Dissertations

Bite force can provide valuable information regarding the physiological ecology of an organism. However, there have been few studies wherein bite force in sharks has been considered. Herein I report on a study of the bite force of four species of sharks with particular emphasis on that of the atlantic sharpnose shark, rhizoprionodon terraenovae. Among the four species examined, blacktip shark, carcharhinus limbatus bite force was significantly higher than that of sharpnose, rhizoprionodon terraenovae. There was no significant difference between the bite force of those species compared with the same for finetooth shark, c. Isodon and spinner shark, c. Brevipinna. …

Land Use Planning And Vernal Pool Conservation In A Southern Maine Town, Robert Carlton Freeman

Electronic Theses and Dissertations

In this dissertation I investigate the impacts of both growth management regulations and vernal pool protection regulations on landscape permeability for wood frogs (Rana sylvatica), a vernal pool-obligate species. Motivated by new legislation in Maine (USA) to protect vernal pools and the species that depend on them, I combined a spatially-explicit economic model of the conversion of undeveloped parcels to residential use with a landscape permeability model for wood frogs. I estimated the economic model using a Bayesian Gibbs Sampler to account for spatial error dependence and used the results to predict future landscape patterns in a focal town, Falmouth, …

Mapping The Dorsal Skin Pigmentation Patterns Of Two Sympatric Populations Of Ambystomatid Salamanders, Ambystoma Opacum And A. Maculatum From Northeast Tennessee., Lok Raj Pokhrel

Electronic Theses and Dissertations

Because of growing concern of habitat fragmentation and its adverse effects on salamander communities in Appalachian region, sympatric populations of ambystomatid salamanders A. opacum and A. maculatum were studied in Northeast Tennessee to address a number of questions: i) the extent of sexual size dimorphism (SSD) in both species, ii) what traits influence the dorsal skin pigmentation and how, iii) whether gender differences in developmental stability occur, and iv) the extent of phenotypic variation within each species. The findings of this study revealed SSD in both species of salamanders. The most parsimonious statistical model was developed that explained the influence …

Status, Distribution, And Density Of White-Tailed Jackrabbits And Black-Tailed Jackrabbits In South Dakota, Dustin J. Schaible

Electronic Theses and Dissertations

The status of jackrabbit (Lepus spp.) populations throughout the Northern Great Plains has been a cause for concern by wildlife managers in recent years and there has been a paucity of information about the ecology of the white-tailed jackrabbit (Lepus townsendii) and the black-tailed jackrabbit (Lepus californicus) in South Dakota. Since there have been little monitoring efforts for hares, 21 permanent spotlight line transects were established across South Dakota for future surveying efforts. These transects were surveyed to obtain baseline information about jackrabbit density and distribution throughout the state. Jackrabbit density was highest in the northwestern portions of the state …

Physical And Behavioral Development Of Nursing Harbor Seal (Phoca Vitulina) Pups In Maine, John P. Skinner

Electronic Theses and Dissertations

Compared to other phocids seals, the maternal investment strategy of the small bodied female harbor seal (Phoca vitulina) is complex. Females are unable to fast for the entire duration of pup rearing and are therefore reliant on resources in the vicinity of the pupping aggregation to continue provisioning their pup by mid-lactation. At the same time, harbor seal pups are highly active during lactation which increases energetic costs to the female but also offers an opportunity for females to influence the behavioral development of her pup. To understand how females maximize their pup's survival it is important to …

The Effects Of Serotonin On The Courtship Behavior Of Drosophilia Melanogaster, Nicholas James Brandmeir

Electronic Theses and Dissertations

In Drosophila, the male courtship ritual is stereotyped and under the control of several genes including fruitless. In previous studies, it has been show that various fruitless alleles cause phenotypic abnormalities in the D. melanogaster courtship ritual. It is also known that there is a high level of co-expression of both the fruitless gene product and serotonin in specific neurons of the Drosophila CNS. This study examines the role of serotonin in the Drosophila male courtship ritual by using a mutant strain, Ddc^ts1,in which the production of serotonin is blocked above 30°C. In this study an increase in temperature caused …

Phenotypic Divergence Of Indigenous And Translocated Arctic Charr (Salvelinus Alpinus) Populations In Maine, Wendy K. Michaud

Electronic Theses and Dissertations

Selection on traits related to trophic ecology is recognized as an important contributing factor in adaptive divergence and speciation. For several freshwater fish species, including Arctic charr (Salvelinus alpinus), such selection is commonly reflected in relationships between diet, habitat use and phenotypic divergence. Trophic specializations that emerge have been extensively studied among sympatric forms, but much less is known of the extent of this type of divergence in allopatry. Trait differences among these forms are also thought to reflect thousands of years of evolution, making it difficult to examine root causes of such divergence in natural populations. Here, I address …

Sexual Dimorphic Social Development And Female Intrasexual Chemical Signaling Of African Elephants (Loxodonta Africana), Jordana M. Meyer

Electronic Theses and Dissertations

Author's abstract: African elephants are a polygynous species in which males and females carry out dimorphic lifestyles. Males search and compete for reproductively active females, while females care for offspring and facilitate group cohesion. The objectives of this study was a) to compare the development of sexually dimorphic behaviors and developmental trends between young male and female wild African elephants and b) to determine the ability of captive female African elephants to discern between the follicular and luteal phase of conspecifics through trunk-tip contacts and the investigation of urine, and whether the reproductive phase of the receiver affected the response …

Endocrine Disruption In Atlantic Salmon (Salmo Salar) Exposed To Pesticides, Benjamin W. Spaulding

Electronic Theses and Dissertations

Since the early 19801s, the numbers of adult Atlantic salmon (Salmo salar) returning to Maine's rivers have been in a general decline. In addition, estimates of parr, freshwater smolt and emigrating smolt populations indicate low overwinter survival rates. Overall, these low numbers, along with several other factors, resulted in the Atlantic salmon in eight rivers in Maine being classified as a distinct population segment under the Endangered Species Act. Because many of the listed rivers are found near lowbush blueberry barrens, I investigated the endocrine disrupting potential and effects of selected blueberry pesticides on Atlantic salmon. An E-SCREEN assay was …

Wetland And Nest Scale Habitat Use By The Four-Toed Salamander (Hemidactylium Scutatum) In Maine, And A Comparison Of Survey Methods, Rebecca J. Chalmers

Electronic Theses and Dissertations

Conserving amphibian populations requires knowledge of a species and its habitat relationships. The four-toed salamander (Hemidactylium scutatum) is listed as Special Concern in Maine and 11 additional states and provinces, Threatened in Illinois, and Endangered in Indiana (Appendix A). Little is known of H. scutatum ecology despite the species' extensive range. Infrequent sightings of H. scutatum throughout its range may indicate either low numbers or that the species' behavior make detection difficult. Records for H. scutatum in Maine existed from only 32 sites before my study, and the total number of occurrences of this species in Maine is …

Effect On Heartbeat Of Drosophila Melanogaster Of Mutations In The Calcium Channel Encoding Cacophony Gene And Its Interaction With The Rna Helicase Mutant Maleless^Napts, Vanessa Mcgowan

Electronic Theses and Dissertations

There is a lack of information concerning the genetics of heart disease, especially of those due to aberrant pacemaker activity. Drosophila melanogaster is an ideal candidate for research in this area because of its suitability to genetic manipulation and its accessible genetic database. What is most compelling, however, is that the genesis of heartbeat is Drosophila is strikingly similar to that in many other organisms, including mammals. The myogenic heart of DrosophiIa melanogaster is stimulated to contract by a caudal pacemaker, which is regulated by ion channel interactions. A voltage-gated calcium channel of PIQ- or N-type is implicated in the …

Evolution Of Lake Malawi Cichlid Fishes (Perciformes: Teleostei), Peter F. Smith

Electronic Theses and Dissertations

The cichlid fish species flocks of East Africa provide a compelling model system in which to study the process of speciation. In Lake Malawi, greater than 1000 species of cichlids have emerged since the filling of the lake basin about 1 million years ago. Over 99% of the Lake Malawi haplochromine cichlids are endemic, suggesting that most of this diversification has taken place within the temporal and spatial boundaries set by the Lake's shores. Moreover, many of these species are endemic to small areas within the lake, indicating that speciation has occurred very recently or perhaps is in progress in …

Systematics Of The Cumacea (Crustacea), Pilar A. Haye

Electronic Theses and Dissertations

Cumaceans are small benthic crustaceans. They have a marine cosmopolitan distribution with diversity increasing with depth. There are approximately 1,400 described species of cumaceans. Despite the fact that they offer a good model for the study of morphological evolution and biogeography, the studies on the Order Cumacea are almost restricted to work at the alpha taxonomy level. This thesis contributes to the systematics of Cumacea. The phylogenetic relationships within the Cumacea were studied using newly obtained partial amino acid sequences from the mitochondria1 gene Cytochrome Oxidase I. Among other findings, phylogenetic analyses revealed that the families Bodotriidae, Leuconidae, and Nannastacidae, …