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Full-Text Articles in Life Sciences

Investigation Of Seed And Seedling Predation And Natural History Of Bushveld Savanna Rodents, Christopher Banotai Oct 2017

Investigation Of Seed And Seedling Predation And Natural History Of Bushveld Savanna Rodents, Christopher Banotai

Masters Theses & Specialist Projects

There is currently a decline in large, old trees within many ecosystems where they play important ecological and economic roles. One ecosystem suffering from this decline is the bushveld savanna of South Africa. One particularly important species in decline is the ecologically, economically, and culturally significant marula tree (Sclerocarya birrea subsp. caffra). This species’ decline is characterized by a steep drop in recruitment of seedlings into the population. Rodents are known to influence plant communities across many ecosystems through herbivory of adult plants as well as predation of seeds and seedlings. This research provides a record of rodent species present ...


Body Shape Diversification Of Pecos Pupfish (Cyprinodon Pecosensis) On Varying Habitats As Evaluated By Geometric Morphometrics, Qianna Xu Apr 2017

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

Masters Theses & Specialist Projects

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


Trophic Dynamic Interactions In A Temperate Karst River, Elizabeth Malloy Dec 2014

Trophic Dynamic Interactions In A Temperate Karst River, Elizabeth Malloy

Masters Theses & Specialist Projects

Surface streams in karst landscapes are often characterized by high nutrient levels due to incomplete filtration through series of innumerable, below-ground conduits. Seasonal growth of the filamentous alga, Cladophora, is typically associated with nutrient-rich waters. This research compared macroinvertebrate food web structure between riverine reaches with contrasting underlying karst topography, nutrient levels, and Cladophora cover during summer 2012 and autumn 2013. Recent work in these reaches found a high correlation between Cladophora cover and nutrient content, particularly nitrate. Four questions were addressed during this study: 1. Do longitudinal trends in algal and consumer δ13C values relate to decreased DIC availability ...


Level Of Uv-B Radiation Influences The Effects Of Glyphosate-Based Herbicide On Fitness Of The Spotted Salamander, Nicholas A. Levis May 2014

Level Of Uv-B Radiation Influences The Effects Of Glyphosate-Based Herbicide On Fitness Of The Spotted Salamander, Nicholas A. Levis

Masters Theses & Specialist Projects

Numerous causes have been implicated in contributing to amphibian population declines since the 1980's, with habitat modification, ultraviolet radiation (UV-B) and environmental contaminants (such as glyphosate-based herbicide) being among the most common. This study identifies the effects of a generic glyphosate-based herbicide (GLY- 4 Plus) on mortality, immune function, body condition, and morphological plasticity of larvae of the spotted salamander (Ambystoma maculatum) under conditions that reflect open and closed canopy light regimes. Larval salamander responses to glyphosate-based herbicide varied depending on UV-B conditions. In general, it appears that an open canopy (i.e. greater UV-B exposure) may confer fitness ...


Wire Netting Reduces African Elephant (Loxodonta Africana) Impact To Selected Large Trees In South Africa, Kelly Derham May 2014

Wire Netting Reduces African Elephant (Loxodonta Africana) Impact To Selected Large Trees In South Africa, Kelly Derham

Masters Theses & Specialist Projects

African elephants (Loxodonta africana) are ecosystem engineers in that they substantially alter the environment through their unique foraging and feeding habits. At high densities, elephants potentially have negative impacts on the environment, specifically to large trees. Because of this, recent increases of elephants in the Associated Private Nature Reserves (APNR) on the Western Boundary of Kruger National Park, South Africa have caused concern regarding the health of several species of tree. My objective was to assess the effectiveness of wrapping protective wire netting around the trunk of the tree in preventing and reducing bark stripping by elephants. 2,668 trees ...


Interference In White Bass Reproduction By Two Introduced Predators In Barren River Lake, Kentucky, Jacob Franklin Fose Dec 2013

Interference In White Bass Reproduction By Two Introduced Predators In Barren River Lake, Kentucky, Jacob Franklin Fose

Masters Theses & Specialist Projects

White bass Morone chrysops are native to the Mississippi River and its tributaries. This range includes the Barren River in south central Kentucky. Over the last thirty years, the population of white bass in Barren River Lake, a reservoir of the Barren River, has been in decline. During that same time, two congeners of white bass have been introduced to the lake. Hybrid striped bass Morone chrysops × Morone saxatilis were introduced in 1979 and yellow bass Morone mississippiensis were first discovered in 2000. Due to the similar life histories and spawning strategies of all three Morone species, I hypothesized that ...


Phenotypic Plasticity Of Oral Jaw Dentition In Archosargus Probatocephalus, Cynthia E. Worcester Dec 2012

Phenotypic Plasticity Of Oral Jaw Dentition In Archosargus Probatocephalus, Cynthia E. Worcester

Masters Theses & Specialist Projects

Phenotypic plasticity, the capacity of a single genotype to exhibit variable phenotypes in different environments, is common in many species. A sample of wild caught Archosargus probatocephalus, also known as sheepshead, from Florida was randomly divided into two treatment groups: one group was fed soft prey, Mercenaria sp. muscle tissue, and the other group was fed hard prey, Mercenaria sp. in the shell, for 365 days. It was hypothesized that the sheepshead fed hard prey would have a thicker tooth enamel layer containing more calcium, and therefore be stronger than the tooth enamel layer of those fed soft prey items ...


Comparison Of Creel Survey Data To Traditional Sampling Techniques In Pit-Lake Fisheries Of Muhlenberg County, Kentucky, Derek L. Rupert May 2012

Comparison Of Creel Survey Data To Traditional Sampling Techniques In Pit-Lake Fisheries Of Muhlenberg County, Kentucky, Derek L. Rupert

Masters Theses & Specialist Projects

Populations of largemouth bass, Micropterus salmoides, and bluegill, Lepomis macrochirus, were evaluated from five pit-lakes in Muhlenberg County, Kentucky, to determine if accurate proportional stock density (PSD) data can be obtained from a mandatory creel survey. It was hypothesized that the proportion of stock-to-quality (300-400mm) and quality (+400mm) largemouth bass from four years (2007-2010) of creel survey data would be statistically similar to those generated through on-site sampling in 2011. Fish were collected via a combination of gill netting, seining, hook-and-line fishing, and boat-mounted electro-fishing. In two of the pit-lakes, the sampling-generated length frequency data was not significantly different from ...


Algal Biomass Accrual In Relation To Nutrient Availability Along A Longitudinal Gradient In The Upper Green River, Kentucky, Mary Douglas Penick Aug 2010

Algal Biomass Accrual In Relation To Nutrient Availability Along A Longitudinal Gradient In The Upper Green River, Kentucky, Mary Douglas Penick

Masters Theses & Specialist Projects

Nutrient limitation in aquatic ecosystems results from a deficiency in nitrogen or phosphorus levels relative to cellular growth needs. Nutrient limitation of freshwater systems is a function of biotic and abiotic factors. Biotic factors include vascular and nonvascular plant community composition. Abiotic factors include underlying bedrock and land-use activities (e.g. agriculture, septic systems). Nutrient availability directly affects growth, productivity, and community structure of primary producers. The purpose of this study was two-fold: (1) to assess the relationship between ambient algal biomass. and in-stream nutrient levels along the longitudinal course of a river through a transition from weak to well-developed ...


Environment-Induced Phenotypic Plasticity In The Teeth Of Hatchery And Wild Largemouth Bass, Micropterus Floridanus, Tamilselvi Selvaraj Aug 2010

Environment-Induced Phenotypic Plasticity In The Teeth Of Hatchery And Wild Largemouth Bass, Micropterus Floridanus, Tamilselvi Selvaraj

Masters Theses & Specialist Projects

Successful stock enhancement of hatchery-reared fish depends heavily on the release of individuals able to demonstrate strong survival skills. Overall survival of fishes is a reflection of a successful blend of physiology, anatomy, and behavior. With fishes being highly phenotypically plastic, the potential exists for all aspects of hatcheryreared fish to vary significantly from their wild counterparts while having potentially adverse effects on their survival after release. Previous analyses have demonstrated significant differences between the feeding behavior of hatchery-reared and wild caught largemouth bass (Micropterus floridanus) in the laboratory, as well as differences in the development of the skull between ...


The Effects Of A Reservoir On Genetic Isolation In Two Species Of Darters, Kerstin Lindsay Edberg Dec 2009

The Effects Of A Reservoir On Genetic Isolation In Two Species Of Darters, Kerstin Lindsay Edberg

Masters Theses & Specialist Projects

The addition of dams into a riverine system causes a wide range of changes (i.e., sedimentation, erosion, thermal) to the river as well as to the fish assemblages of that river. Although there have been many studies documenting the changes that occur to the fish assemblages in the impounded river, there have been fewer studies examining the effects of a reservoir on the fish inhabiting the tributaries upstream of the impoundment. One possible impact of a reservoir could be to act as a barrier to fish migration between streams.
To determine if reservoirs restrict migration, the genetic diversity of ...


The Development And Role Of Peripheral Auditory Structures In Otocinclus Affinis, Sri Kiran Kumar Reddy Botta Nov 2009

The Development And Role Of Peripheral Auditory Structures In Otocinclus Affinis, Sri Kiran Kumar Reddy Botta

Masters Theses & Specialist Projects

Loricariidae is a very diverse family of catfishes found primarily in the Amazon River basin. These catfishes have a unique characteristic feature of having fenestrae (holes) in the skull region (compound pterotic bone) adjacent to their bi-lobed swim bladder. Since the swim bladders and the compound pterotic may act as an external ear for hearing in this taxon, I hypothesized that these swim bladders structures have an acoustical functional in the loricariid Otocinclus affinis. In order to understand the development of these structures in O. affinis, I first monitored the ontogeny of the compound pterotic bone by clearing and staining ...


Assessment Of The Endangered Species Podarcis Carbonelli On A Microgeographic Scale: A Molecular, Morphological And Physiological Approach, Maria Clara Figueirinhas Do Amaral Aug 2009

Assessment Of The Endangered Species Podarcis Carbonelli On A Microgeographic Scale: A Molecular, Morphological And Physiological Approach, Maria Clara Figueirinhas Do Amaral

Masters Theses & Specialist Projects

The lizard Podarcis carbonelli is an endangered species endemic to the Iberian Peninsula. One location where this species occurs is at the Berlengas Natural Preserve, an Atlantic archipelago off the coast of Portugal. These island populations are geographically separated from nearby mainland populations. The fundamental question is, are these insular individuals distinct from the mainland populations? Four localities were chose for comparison: two island populations and two nearby coastal populations. We assessed this question using three distinct approaches: molecular, morphological and physiological approach. We sequenced the 12S RNA, the mtDNA Control Region and the 7th intron of the !-fibrinogen gene ...


A Comparative Ecological Study Of Two Sister Species Of Darters In Kentucky, Etheostoma Kantuckeense And Etheostoma Lawrencei, Bjorn Victor Schmidt May 2009

A Comparative Ecological Study Of Two Sister Species Of Darters In Kentucky, Etheostoma Kantuckeense And Etheostoma Lawrencei, Bjorn Victor Schmidt

Masters Theses & Specialist Projects

Etheostoma kantuckeense and E. lawrencei are former members of the wide ranging E. spectabile species complex. Etheostoma kantuckeense is endemic to the Barren River Basin in Southern Kentucky and Northern Tennessee, while E. lawrencei occurs in the Green River, Salt River, and Cumberland River Basins of Central and Eastern Kentucky. Isolation of populations within these drainages has allowed for a relatively recent evolutionary divergence, leading to slight differences in morphology. This study was conducted to address if geographical isolation has led to measurable differences in the ecology of these two species. In particular, habitat preference across three spatial scales and ...


An Analysis Of The Heavy Metal Content Of The Scales Of Several Fishes In Southwestern Kentucky, Thomas Dahl May 1978

An Analysis Of The Heavy Metal Content Of The Scales Of Several Fishes In Southwestern Kentucky, Thomas Dahl

Masters Theses & Specialist Projects

Scales of the stoneroller, Campostoma anomalum (Rafinesque), common shiner, Notropus cornutus (Mitchill), and the bluntnose minnow, Pimephales notatus (Rafinesque) were analyzed by means of atomic absorption spectrophotometry to determine levels of cadmium, calcium, copper, iron, lead, manganese, nickel and zinc. Metal concentrations were determined seasonally and relationship established between scale metal content and environmental water metal levels.

Calcium, iron manganese and zinc were found in all samples analyzed. Cadmium, copper, lead and nickel were not observed in measurable quantities.

Metal concentrations varied interspecifically, but most showed little fluctuation in response to increased metal content of the water. Elemental composition of ...