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Full-Text Articles in Natural Resources and Conservation

Estimating The Onset And Extent Of Dieback Of Phragmites Australis Using The Normalized Difference Vegetation Index And Remotely Sensed Land Cover Classifications, Aimee M. Beaudette Jun 2020

Estimating The Onset And Extent Of Dieback Of Phragmites Australis Using The Normalized Difference Vegetation Index And Remotely Sensed Land Cover Classifications, Aimee M. Beaudette

LSU Master's Theses

Phragmites australis is cosmopolitan plant species with an invasive variety present throughout most of North America. In the Balize Delta, Louisiana, USA, P. australis plays an important role in combatting subsidence, maintaining navigation channels, and protecting interior fish and wildlife habitat from waves and storm surge. In 2016 a dieback of P. australis was reported by wetland managers, coinciding with the appearance of an invasive Asian scale insect (Nipponaclerda biwakoensis), though the specific cause is still unknown. Two previous efforts attempted to identify the onset of dieback conditions met with limited success. Using Landsat images from 1985 to …


An Ecopath With Ecosim Analysis On Offshore Petroleum Platform Influences On Gulf Of Mexico Red Snapper, Valentin Gomez Apr 2020

An Ecopath With Ecosim Analysis On Offshore Petroleum Platform Influences On Gulf Of Mexico Red Snapper, Valentin Gomez

LSU Master's Theses

Offshore oil and gas platforms have had a significant presence in the Gulf of Mexico since the 1950s. An important secondary function of these structures is that they provide artificial habitat to fisheries, most notably Red snapper. Policy changes intended to reduce the risk associated with aging infrastructure have reduced the number of standing platforms from 4044 to 1867 from 2001 to 2018. The effect this loss of habitat has on Red snapper was tested by creating three scenarios of platform changes and modeling the perturbation from 2005 to 2050. The simulation was accomplished using the ecological model Ecopath with …


Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms Apr 2020

Biogeography Of Biological Control: Spatial Variation In Agent-Host Interactions, Nathan Harms

LSU Doctoral Dissertations

Management of plant invasions using biological control has the potential to generate spatial patterns which reflect geographic or genetic variation in invader or control agents. Despite its rarity in practice, investigations into the biogeography of interacting species (i.e., plant invader and control agent) in the context of biological control can lend insights into species distribution-abundance patterns and provide predictions for spatial variation in control success. I explored spatial variability in biological control agent-plant interactions using two wetland weed study systems with large geographic distributions: flowering rush (Butomus umbellatus L.) and alligatorweed (Alternanthera philoxeroides (Mart.) Griseb). Through literature and …


Conservation Potential And Mechanisms Of Avian Decline In Experimentally Fragmented And Regenerating Amazonian Rainforest, Cameron Lee Rutt Mar 2020

Conservation Potential And Mechanisms Of Avian Decline In Experimentally Fragmented And Regenerating Amazonian Rainforest, Cameron Lee Rutt

LSU Doctoral Dissertations

Twenty percent of the Brazilian Amazon has now been deforested, and deforestation rates are increasing. Yet the process of deforestation threatens biodiversity beyond the direct loss of habitat by inducing edge effects and creating forest fragments. In the tropics, among the most vulnerable birds to these human disturbances are a group of insectivorous species that forage on or near the ground. A variety of mechanisms have been proposed to explain these declines, but evidence for these hypotheses remains scare or equivocal. In this study, we examine three proposed mechanisms—physiological constraints to bright light, reduced breeding activity and nest success, and …


Reproductive Parameters And Female Breeding Season Survival Of Rio Grande Wild Turkeys In South Central Texas, Jacob White Oct 2019

Reproductive Parameters And Female Breeding Season Survival Of Rio Grande Wild Turkeys In South Central Texas, Jacob White

LSU Master's Theses

Historically, Rio Grande wild turkeys in south central Texas have been at lower densities than other portions of the state. Within the Oak-Prairie Wildlife District of Texas, Rio Grande wild turkey regulatory restrictions are different for counties in the eastern and western portions of the ecoregion. Due to perceived increases in turkey density in the eastern portion of the ecoregion (hereafter 1-bird zone), Texas Parks and Wildlife Department (TPWD) considered increasing the bag limit to match counties in the western portion of the district (hereafter 4-bird zone) in order to increase hunting opportunities. However, if regulatory changes are to be …


Cogongrass (Imperata Cylindrica (L.) Beauv.) In Louisiana: Cause And Consequence, Lorissa A. Radunzel-Davis Jun 2019

Cogongrass (Imperata Cylindrica (L.) Beauv.) In Louisiana: Cause And Consequence, Lorissa A. Radunzel-Davis

LSU Master's Theses

Cogongrass (Imperata cylindrica (L.) Beauv.), an invasive species from East Asia, is found worldwide and is problematic in several countries. In the United States, it grows primarily in the Southeast, reducing biodiversity by growing in dense patches and potentially causing mortality and reducing value of native and planted pinelands due to a high burning temperature. Using Lee Memorial Forest, a Louisiana State University AgCenter property in Washington Parish as a study site, this thesis explores cogongrass in Louisiana with emphasis on soil microbes and soil legacy effects on native plant species. Cogongrass populations at Lee Memorial Forest were more …


Reproductive Parameters And Methodologies For The Culture Of Golden Topminnows (Fundulus Chrysotus) And Bluenose Shiners (Pteronotropis Welaka), Jacob A. Fetterman Jun 2019

Reproductive Parameters And Methodologies For The Culture Of Golden Topminnows (Fundulus Chrysotus) And Bluenose Shiners (Pteronotropis Welaka), Jacob A. Fetterman

LSU Master's Theses

The global ornamental fish trade has expanded over the past 20 years, requiring captive rearing methods to be improved or developed for species of interest. Aquaculture of desirable species is preferable over wild harvest to conserve natural habitats and biodiversity. This thesis focused on improving culture methods for Golden Topminnows Fundulus chrysotus and developing culture methods for Bluenose Shiners Pteronotropis welaka, both native fishes of the southeastern United States with ornamental demand. A combination of reproductive metric analyses, examination of historical collections, and captive spawning trials were employed to target specific objectives for each species. In female Golden Topminnows, …


Effects Of Oil And Gas Development On Waterfowl Nesting Ecology In The Bakken Formation Of North Dakota, Cassandra G. Skaggs Mar 2019

Effects Of Oil And Gas Development On Waterfowl Nesting Ecology In The Bakken Formation Of North Dakota, Cassandra G. Skaggs

LSU Master's Theses

The Prairie Pothole Region (PPR) is one of the most important areas on the continent for grassland-nesting birds. Thirty percent of the PPR overlaps the Bakken shale formation where rapidly accelerating oil and gas development has the potential to impact millions of breeding waterfowl. While oil and gas development has negatively affected other ground-nesting birds such as sagebrush passerines and Greater Sage-Grouse (Centrocercus urophasianus) in Wyoming, the potential impact on breeding waterfowl in the PPR is unknown. In addition, the PPR landscape is already heavily fragmented by agriculture, and increasing land conversion and disturbance from petroleum extraction may further …


Environmental Controls On Dissolved Carbon Export And River Geochemistry - A Case Study In The Mississippi-Atchafalaya System, Jeremy Reiman Mar 2019

Environmental Controls On Dissolved Carbon Export And River Geochemistry - A Case Study In The Mississippi-Atchafalaya System, Jeremy Reiman

LSU Master's Theses

Rivers serve as an important medium for the exchange of elements between land, ocean, and atmosphere. This thesis consists of three interconnected studies with the overarching goal of analyzing the environmental factors influencing dissolved carbon dynamics and river geochemistry in large rivers. These studies utilized river water samples and in-stream measurements collected from the Mississippi and Atchafalaya Rivers at hourly to monthly intervals between 2013 to 2018, along with ambient river and meteorological data downloaded from public-access databases. Results indicate substantially higher dissolved organic carbon concentrations (DOC, 611 ±181 µmol L-1) but lower concentrations of dissolved inorganic carbon …


Relating Diets And Food Availability To Long-Term Population Trends Of Lesser Scaup Wintering On Lake Pontchartrain, Louisiana, Clay Michael Stroud Apr 2018

Relating Diets And Food Availability To Long-Term Population Trends Of Lesser Scaup Wintering On Lake Pontchartrain, Louisiana, Clay Michael Stroud

LSU Master's Theses

Lake Pontchartrain provides wintering habitat for a continentally-significant proportion of lesser scaup (Aythya affinis). Mid-winter aerial surveys indicate dramatic variation in annual scaup abundance (0–1,194,907), though the mechanisms driving fluctuations have not been previously investigated. In response to natural and anthropogenic disturbances, species composition, abundance, and size structure of benthic invertebrate populations in Lake Pontchartrain exhibit drastic variability among years. Given that wintering scaup feed primarily on mollusks, environmental disturbances have the potential to influence scaup dynamics on the estuary by altering the benthic community. To diagnose trophic linkages and variation in scaup abundance, we collected ducks (n=60) …


Gastrointestinal Helminth Prevalence In Lesser Scaup (Aythya Affinis) Wintering On Lake Pontchartrain, Louisiana, Usa, Sydney Cottingham Apr 2018

Gastrointestinal Helminth Prevalence In Lesser Scaup (Aythya Affinis) Wintering On Lake Pontchartrain, Louisiana, Usa, Sydney Cottingham

Honors Capstones

No abstract provided.


Effects Of Timber Harvest On Avian Abundance And Diversity, Mckenzie Brandon Apr 2017

Effects Of Timber Harvest On Avian Abundance And Diversity, Mckenzie Brandon

Honors Capstones

No abstract provided.


Identification Of Morphemes And The Effect Of Memory Load On Second Language Learning, James A. Hebert Dec 2015

Identification Of Morphemes And The Effect Of Memory Load On Second Language Learning, James A. Hebert

Honors Capstones

No abstract provided.


Association Of Drd4 Gene Polymorphisms With Range In Species Of The Genus Copsychus, Jocelyn B. Miller Apr 2014

Association Of Drd4 Gene Polymorphisms With Range In Species Of The Genus Copsychus, Jocelyn B. Miller

Honors Capstones

No abstract provided.


Preliminary Assessment Of Hybridization And Introgression Of Morone Species In The Toledo Bend Reservoir, Louisiana, Kelsey L. Daroca Jul 2011

Preliminary Assessment Of Hybridization And Introgression Of Morone Species In The Toledo Bend Reservoir, Louisiana, Kelsey L. Daroca

Honors Capstones

No abstract provided.