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Full-Text Articles in Ecology and Evolutionary Biology

Dolphin Behavioral Responses To Uncrewed Aerial Systems As A Function Of Exposure, Height, And Type, Savannah Damiano May 2023

Dolphin Behavioral Responses To Uncrewed Aerial Systems As A Function Of Exposure, Height, And Type, Savannah Damiano

Electronic Theses and Dissertations

Uncrewed aerial systems (UAS) are becoming a standard tool in the study of cetaceans, however, a comparative assessment of animal responses to UAS has not been established to gauge the most effective systems for cetacean study. We utilized Dolphin Quest Bermuda’s eleven bottlenose dolphins as subjects for such an investigation taking place over five weeks in 2022 and five weeks in 2023. The dolphins were evaluated for investigative behavioral responses to six off-the-shelf UAS types and a custom fixed wing system. Each UAS was flown in decreasing height vertically above the main dolphin lagoon to evaluate dolphin behavioral responses in …


Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais Dec 2022

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …


Cross-Modal Perception Of Identity By Sound And Taste In Bottlenose Dolphins, Jason N. Bruck, Sam F. Walmsley, Vincent M. Janik May 2022

Cross-Modal Perception Of Identity By Sound And Taste In Bottlenose Dolphins, Jason N. Bruck, Sam F. Walmsley, Vincent M. Janik

Faculty Publications

While studies have demonstrated concept formation in animals, only humans are known to label concepts to use them in mental simulations or predictions. To investigate whether other animals use labels comparably, we studied cross-modal, individual recognition in bottlenose dolphins (Tursiops truncatus) that use signature whistles as labels for conspecifics in their own communication. First, we tested whether dolphins could use gustatory stimuli and found that they could distinguish between water and urine samples, as well as between urine from familiar and unfamiliar individuals. Then, we paired playbacks of signature whistles of known animals with urine samples from either the same …


Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum May 2022

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …


Assessing The Live Bait Industry And The Ecological Status Of Invasive Cyprinodontiformes (Sheepshead Minnow: Cyprinodon Variegatus And Gulf Killifish: Fundulus Grandis) In Texas Streams, Erin Shepta May 2022

Assessing The Live Bait Industry And The Ecological Status Of Invasive Cyprinodontiformes (Sheepshead Minnow: Cyprinodon Variegatus And Gulf Killifish: Fundulus Grandis) In Texas Streams, Erin Shepta

Electronic Theses and Dissertations

The introduction of invasive species is one of the greatest threats to global biodiversity. Once established, invasive species often cause irreversible ecological damage on native communities. Here, I investigated the pathway of introduction and ecological impacts of the sheepshead minnow (C. variegatus) and the gulf killifish (F. grandis). Both species were thought to have been introduced into inland Texas waters via bait-bucket releases and have caused native populations of their inland congeners to decline. While I did not find evidence that either species were being sold in inland shops, bait industry experts did reveal other potentially …


Detection And Occurrence Of Nerodia Harteri (Serpentes: Colubridae) In An Upper Portion Of The Brazos River Watershed, Jessica Yates May 2022

Detection And Occurrence Of Nerodia Harteri (Serpentes: Colubridae) In An Upper Portion Of The Brazos River Watershed, Jessica Yates

Electronic Theses and Dissertations

Semiaquatic snakes are disproportionately impacted by habitat alteration adjacent to wetlands because of their reliance on both terrestrial and aquatic habitats. Brazos River Watersnakes, Nerodia harteri, are endemic natricines with one of the most restricted geographic ranges in North America. I quantified detection and site occupancy probabilities of N. harteri and its sympatric congeners (N. erythrogaster and N. rhombifer), as well as microhabitat selection within the Nerodia community. Within occupied transects, search effort was positively correlated with detecting N. harteri, whereas environmental and/or habitat variables were better predictors for detecting the sympatric congeners. Microhabitat selection between …


An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner May 2022

An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner

Electronic Theses and Dissertations

Rabies remains a global public health issue with a wide variety of neurological symptoms such as confusion, slight paralysis, hypersalivation, and hydrophobia. Rabies is usually fatal once symptoms appear. Many species are reservoirs for rabies, such as foxes, racoons, and wild dogs, which in turn can transmit the disease to humans, leading to complex transmission chains. There is a long latent period of rabies, between 1 to 3 months after infection, which further complicates control efforts. Mathematical modeling is a valuable tool in the study of infectious disease outbreaks and there have been many models applied to rabies outbreaks. However, …


Spatiotemporal Factors Affecting The Occupancy And Phenology Of A Declining Songbird (Bachman's Sparrow - Peucaea Aestivalis) At The Western Extent Of Its Range, Liam G. Wolff May 2022

Spatiotemporal Factors Affecting The Occupancy And Phenology Of A Declining Songbird (Bachman's Sparrow - Peucaea Aestivalis) At The Western Extent Of Its Range, Liam G. Wolff

Electronic Theses and Dissertations

The Bachman’s Sparrow (Peucaea aestivalis) is a declining songbird that occurs throughout the southeastern United States. Bachman’s Sparrow is a Species of Greatest Conservation Need in Texas, but information crucial to management efforts, such as factors affecting their detectability and occupancy, is lacking. I investigated the predictors of Bachman’s Sparrow occupancy and phenology in Texas using detections from autonomous recording units coupled with site characteristics and weather data. My results indicate that Bachman’s Sparrow occupancy is associated with increasing herbaceous ground cover and decreasing basal area, distance to the nearest source population, and basal area when canopy height …


Fish Community Assembly At Multiple Spatial Scales In East Texas Streams, Jake R. Swanson May 2022

Fish Community Assembly At Multiple Spatial Scales In East Texas Streams, Jake R. Swanson

Electronic Theses and Dissertations

Stream communities are structured by environmental processes that vary in strength across different spatiotemporal scales. Therefore, revealing how stream fish communities are influenced by environmental gradients may clarify how communities respond to disturbance associated with anthropogenic change. I investigated the relative role environmental variables play in the processes that structure the taxonomic and functional diversity of stream fish communities, as well as historical trends in occurrence and local habitat associated with a species of greatest conservation need within east Texas. The results of this study indicate that stream sites with more habitat complexity and stability support a more taxonomically and …


Urbanization Increases Isolation Of A Threatened Fish Species In East Texas Streams: A 20-Year Perspective, Zachary Hutchens Apr 2022

Urbanization Increases Isolation Of A Threatened Fish Species In East Texas Streams: A 20-Year Perspective, Zachary Hutchens

Undergraduate Research Conference

We conducted monthly surveys of fish and in-stream habitat conditions from August 2020 to August 2021 in reaches along Banita Creek and La Nana Creek to investigate ecology and population status of the Sabine shiner (Notropis sabinae) within these streams. On average, Banita Creek had shallow water with low flow, more diverse instream habitats, and lower values of salinity, conductivity, and turbidity compared La Nana Creek. The movements of Sabine shiners were tracked monthly using Visual Implant Elastomer tags. Over a year-long survey, we collected 267 Sabine shiners from Banita Creek and 10 individuals from La Nana Creek. Out of …


Aquatic Macroinvertebrates As Sentinels Of Changes In Local Stream Conditions In East Texas, Courtney Plummer, Erin Shepta Apr 2022

Aquatic Macroinvertebrates As Sentinels Of Changes In Local Stream Conditions In East Texas, Courtney Plummer, Erin Shepta

Undergraduate Research Conference

Study objective: To use aquatic macroinvertebrates to assess the habitat quality and biological conditions of a stream, La Nana Creek, impacted by different land use.


Evolutionary Analyses Of Visual Opsin Genes In Frogs And Toads: Diversity, Duplication, And Positive Selection, Ryan K. Schott, Leah Perez, Matthew Kwiatkowski, Vance Imhoff, Jennifer M. Gumm Jan 2022

Evolutionary Analyses Of Visual Opsin Genes In Frogs And Toads: Diversity, Duplication, And Positive Selection, Ryan K. Schott, Leah Perez, Matthew Kwiatkowski, Vance Imhoff, Jennifer M. Gumm

Faculty Publications

Among major vertebrate groups, anurans (frogs and toads) are understudied with regard to their visual systems, and little is known about variation among species that differ in ecology. We sampled North American anurans representing diverse evolutionary and life histories that likely possess visual systems adapted to meet different ecological needs. Using standard molecular techniques, visual opsin genes, which encode the protein component of visual pigments, were obtained from anuran retinas. Additionally, we extracted the visual opsins from publicly available genome and transcriptome assemblies, further increasing the phylogenetic and ecological diversity of our dataset to 33 species in total. We found …


Natural Regeneration Dynamics And Survival Influenced By Abiotic And Biotic Factors In A Bottomland Hardwood Forest, Lydia J. Voth Rurup Dec 2021

Natural Regeneration Dynamics And Survival Influenced By Abiotic And Biotic Factors In A Bottomland Hardwood Forest, Lydia J. Voth Rurup

Electronic Theses and Dissertations

Riparian ecosystems are vital to the landscape, providing critical services including water filtration and purification, flood and erosion control, carbon sequestration, biodiversity support, and aesthetic value. Bottomland hardwood forests, however, are threatened by invasive species, land loss/conversion, inconsistent or absence of harvesting disturbances, and altered hydrological patterns, leading to reduced success of desired, native species. This research assessed regeneration dynamics and one-year survival in a seasonally-flooded bottomland hardwood forest at Boggy Slough Conservation Area in East Texas to identify abiotic and biotic factors important for successful establishment of native regeneration. Areas sampled included two that were previously treated with herbicide …


Cetacean Acousticwelfare In Wild And Managed-Care Settings: Gaps And Opportunities, Paige E. Stevens, Heather Hill, Jason N. Bruck Nov 2021

Cetacean Acousticwelfare In Wild And Managed-Care Settings: Gaps And Opportunities, Paige E. Stevens, Heather Hill, Jason N. Bruck

Faculty Publications

Cetaceans are potentially at risk of poor welfare due to the animals’ natural reliance on sound and the persistent nature of anthropogenic noise, especially in the wild. Industrial, commercial, and recreational human activity has expanded across the seas, resulting in a propagation of sound with varying frequency characteristics. In many countries, current regulations are based on the potential to induce hearing loss; however, a more nuanced approach is needed when shaping regulations, due to other non-hearing loss effects including activation of the stress response, acoustic masking, frequency shifts, alterations in behavior, and decreased foraging. Cetaceans in managedcare settings share the …


Food-Web And Functional Trait Community Structure Of Predator Assemblages In Pine Forests Under Different Management Regimes, Connor Adams May 2021

Food-Web And Functional Trait Community Structure Of Predator Assemblages In Pine Forests Under Different Management Regimes, Connor Adams

Electronic Theses and Dissertations

Anthropogenic activities can alter natural disturbance regimes in ecosystems, and thereby affect the structure and function of biological diversity. As many of the world’s ecosystems are degraded beyond natural recovery, well-defined restoration goals are necessary to maintain the ecological processes that provide valuable ecosystem services. Utilizing taxonomic, functional, and food-web approaches, I investigated the impacts of forest management practices in structuring predator communities in two pine forest systems of eastern Texas. The results of this study indicate that the increased frequency of forest management practices such as prescribed fires and thinning operations encourages predator diversity while increasing functional and trophic …


The Bees Of Two Sites In The Big Thicket National Preserve, Texas, With A Consideration Of The Effects Of A Rare Flooding Event, Archie Ray Sauls Jr. May 2021

The Bees Of Two Sites In The Big Thicket National Preserve, Texas, With A Consideration Of The Effects Of A Rare Flooding Event, Archie Ray Sauls Jr.

Electronic Theses and Dissertations

Native bees are an important part of terrestrial ecosystems due to their coevolution with flowering plants. This study catalogued the bee fauna of two sandyland sites in the Big Thicket National Preserve and assessed whether a community was impacted by a historic hurricane-induced flooding event. It was hypothesized that a change in diversity metrics would be evident following the flood. Datasets were analyzed for differences in species richness, abundance, evenness, and Shannon’s diversity. Similarities between datasets were also assessed using the multivariate tests analysis of similarity (ANOSIM) and similarity of percentages (SIMPER). At two sites over two years of sampling …


Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk May 2021

Effects Of Anthropogenic Light And Noise On Anuran Breeding Behavior, Ashley Kobisk

Electronic Theses and Dissertations

The natural environment can be negatively impacted by a variety of human activities, including the production of artificial light at night and anthropogenic noise. Recent studies suggest that pollution from anthropogenic light and noise alters animal behavior. Despite being highly nocturnal and vocal animals, little attention has been given to anurans and the effects artificial light at night and anthropogenic noise have on their behavior. This study investigated the effects of artificial light at night and anthropogenic noise on anuran breeding systems in eastern Texas. Specifically, this study investigated whether (1) artificial light and anthropogenic noise altered calling behavior in …


Microplastics: Nacogdoches County’S Hidden Threat, Jordan Stanford, Sydney Matlock, Courtney Sims, Samantha Montes Apr 2021

Microplastics: Nacogdoches County’S Hidden Threat, Jordan Stanford, Sydney Matlock, Courtney Sims, Samantha Montes

Undergraduate Research Conference

Microplastics and their threat to marine environments are well known, but studies in freshwater environments are few and far between. Microplastics can be created by the breaking down of plastics or in the process of making plastics. They affect biological lifeforms in a multitude of ways, water temperature, permeability of the sediment. Pollution in Texas waterways have motivated groups like the Environmental Protection Agency, Trash Free Texas, and Environment Texas to get involved. The objectives of this study are two analyze Bonita and La Nana Bayou for microplastic presence and to educate and create awareness for Nacogdoches County on microplastics. …


Identification And Functional Analysis Of Thadh1 And Thadh4 Genes Involved In Tolerance To Waterlogging Stress In Taxodium Hybrid ‘Zhongshanshan 406’, Lei Xuan, Jianfeng Hua, Fan Zhang, Zhiquan Wang, Xiaoxiao Pei, Ying Yang, Yunlong Yin, David Creech Jan 2021

Identification And Functional Analysis Of Thadh1 And Thadh4 Genes Involved In Tolerance To Waterlogging Stress In Taxodium Hybrid ‘Zhongshanshan 406’, Lei Xuan, Jianfeng Hua, Fan Zhang, Zhiquan Wang, Xiaoxiao Pei, Ying Yang, Yunlong Yin, David Creech

Faculty Publications

The Taxodium hybrid ‘Zhongshanshan 406’ (T. hybrid ‘Zhongshanshan 406’) [Taxodium mucronatum Tenore × Taxodium distichum (L.). Rich] has an outstanding advantage in flooding tolerance and thus has been widely used in wetland afforestation in China. Alcohol dehydrogenase genes (ADHs) played key roles in ethanol metabolism to maintain energy supply for plants in low-oxygen conditions. Two ADH genes were isolated and characterized—ThADH1 and ThADH4 (GenBank ID: AWL83216 and AWL83217—basing on the transcriptome data of T. hybrid ‘Zhongshanshan 406’ grown under waterlogging stress. Then the functions of these two genes were investigated through transient expression and overexpression. The results showed that the …


Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Daniel R. Unger, David L. Kulhavy, Chris M. Schalk Dec 2020

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Daniel R. Unger, David L. Kulhavy, Chris M. Schalk

Student Publications

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high …


Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy Dec 2020

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy

Electronic Theses and Dissertations

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high …


An Invasive Species As A Threat To Native Biodiversity: Larval Competition Between Native Anurans And An Invasive Treefrog, Mckenzie Wasley Dec 2020

An Invasive Species As A Threat To Native Biodiversity: Larval Competition Between Native Anurans And An Invasive Treefrog, Mckenzie Wasley

Electronic Theses and Dissertations

Cuban Treefrogs (Osteopilus septentrionalis) are established in Florida and Louisiana and have invasive potential further westward, possibly impacting native anurans at multiple life stages. In anurans, competition at the larval stage can decrease adult fitness through slower development and smaller size at metamorphosis, ultimately decreasing recruitment rates. To examine the potential impacts of O. septentrionalis at the larval life-history stage, I quantified activity levels and growth of their tadpoles and those of two anurans native to eastern Texas: Green Treefrogs (Hyla cinerea) and Gulf Coast Toads (Incilius nebulifer). Tadpoles of the three species were …


Characterizing Patterns In Texas Gulf Coast Beach Dune Plant Species Composition, Cody Foster Dec 2020

Characterizing Patterns In Texas Gulf Coast Beach Dune Plant Species Composition, Cody Foster

Electronic Theses and Dissertations

Regional vegetation patterns of Texas beach plant communities were analyzed using cluster analysis, ANOSIM, SIMPER, NMDS, and ISA for fives zones representing the foredune complex of twenty Gulf Coast beaches. ANOVA revealed that zones differ in terms of percent bare sand, percent vegetative cover, and species richness. Cluster Analysis, ANOSIM, and SIMPER results indicate that Texas beaches can be divided into northern and southern regions based on differences in species composition of plant communities. Indicator Species Analysis (ISA) indicates that northern beaches are characterized by the presence of Rayjacksonia phyllocephala, Ambrosia Strophostyles, Ambrosia psilostachya, and Panicum amarum …


Surface Levels, Keisha Brathwaite Aug 2020

Surface Levels, Keisha Brathwaite

Electronic Theses and Dissertations

Surface Levels are depictions of unobserved and imperceptible realities of many phytoplankton exteriors. The exhibition explores various structures, textures, and repetitious forms from microscopic surfaces of objects that cannot be seen with unaided eyes. Electron microscopy is used to perceive and analyze these otherwise unseeable surfaces in depth. Magnifications provide a reference in creating three- and two-dimensional works that are minimalistic and abstract at a visible level. This abstract 3D/2D image collection is translated into material expressions using acrylic sheets, acrylic ink, and wood as the main media for construction of individual works. Collectively, they serve to make the invisible …


Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow May 2020

Glare Reduction By Dark Facial Markings And Bills In Birds, Clara Lebow

Electronic Theses and Dissertations

Avian facial plumage, bill coloration, and feather microstructure may serve one or more adaptive functions. Several researchers have proposed that dark eyestripes, bills, and facial masks aid in reducing glare, however, there have been relatively few tests of this hypothesis. Dark facial markings have been shown to have an adaptive glare-reduction function in recent field studies of a few species, but this hypothesis has never been tested in a broad multispecies analysis. It is likely that feather microstructure influences feather brightness and has an effect on the efficacy of glare reduction properties of feathers. I examined the link between dark …


Personality In Stomatopod Crustaceans, Jillian Page Blenderman Apr 2020

Personality In Stomatopod Crustaceans, Jillian Page Blenderman

Electronic Theses and Dissertations

Stomatopods, or mantis shrimp, are small, predatory crustaceans of tropical and subtropical waters. Mantis shrimp research has focused largely on their agonistic interactions and complex visual systems. Despite their broad behavioral repertoire, stomatopods have not yet been investigated for consistent behavioral differences at the individual level, referred to as animal personality. Fifteen individual Neogonodactylus oerstedii were tested in three scenarios designed to measure potential differences in behaviors: 1) exploration of a novel environment, 2) response to and recovery from a startling event, and 3) response to a novel object. Each individual went through the series of tests twice, with a …


Visual Opsin Diversity In Anurans, Leah Perez Aug 2019

Visual Opsin Diversity In Anurans, Leah Perez

Electronic Theses and Dissertations

Among major vertebrate groups, anurans are understudied with regards to their visual systems and how they function. This study sampled North American anurans representing diverse evolutionary and life histories and which likely possess visual systems adapted to meet different ecological needs. Using standard molecular techniques, sequences were obtained for four opsins—the protein component of visual pigments—expressed in anuran retinas. Amino acid sequences of the genes RH1, LWS, SWS1, and SWS2 were compared across taxa to identify variable sites, as such variation can shift the spectral sensitivity of visual pigments and thus alter dim-light and color vision. Some of the amino …


Move It Or Lose It: Interspecific Variation In Risk Response Of Pond-Breeding Anurans, Philip Matich, Christopher M. Schalk Jan 2019

Move It Or Lose It: Interspecific Variation In Risk Response Of Pond-Breeding Anurans, Philip Matich, Christopher M. Schalk

Faculty Publications

Changes in behavior are often the proximate response of animals to human disturbance, with variability in tolerance levels leading some species to exhibit striking shifts in life history, fitness, and/or survival. Thus, elucidating the effects of disturbance on animal behavior, and how this varies among taxonomically similar species with inherently different behaviors and life histories is of value for management and conservation. We evaluated the risk response of three anuran species—southern leopard frog (Lithobates sphenocephalus), Blanchard’s cricket frog (Acris blanchardi), and green tree frog (Hyla cinerea)—to determine how differences in microhabitat use (arboreal vs …


Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney Aug 2018

Breeding Bird Response To Post Oak Savanna Restoration Seven Years Post Management In Eastern Texas, Courtney Mcinnerney

Electronic Theses and Dissertations

Oak savannas were once an abundant vegetation type in the Midwestern United States that have now declined to <1% of their original distribution. Historically, natural disturbances such as periodic fire and grazing maintained oak savannas, but these have been reduced or eliminated, resulting in woody encroachment and subsequent habitat loss and degradation. In 2009-10, a baseline, pre-restoration study was completed to determine vegetation characteristics, breeding bird abundances, nest success, and nest site selection at the Gus Engeling Wildlife Management Area (GEWMA) in eastern Texas. The results showed a lack of savanna vegetation structure on degraded sites and few savanna or grassland obligate bird species. The goal of this study was to determine how breeding birds of oak savanna vegetation types in eastern Texas respond to restoration effects 7 years after initial management. Post-restoration surveys completed in 2016-17 showed a change in avian assemblages from a more woodland dominated community to grassland/savanna community. The presence and breeding of savanna obligate species dickcissel (Spiza americana) and lark sparrow (Chondestes grammacus) indicates that the restoration was successful. The presence of savanna species can be linked to the herbaceous vegetation that was restored to more closely resemble historic oak savanna structure and can quantify the success of restoration efforts.


Delineating Metrics Of Diversity For A Snake Community In A Rare Ecosystem, Zachary John Marcou Aug 2018

Delineating Metrics Of Diversity For A Snake Community In A Rare Ecosystem, Zachary John Marcou

Electronic Theses and Dissertations

Snakes are among the least understood vertebrate groups despite their considerable diversity. A diverse community of snakes in an ecosystem can indicate a complex habitat structure that is capable of supporting a robust assemblage of other biota. I used remote photography arrays (RPA) to quantify metrics of diversity for the snake community occurring in a ~7,000–ha tract of contiguous Longleaf Pine (Pinus palustris) Savanna within the Angelina National Forest (ANF; Angelina and Jasper Cos., TX), over the course of two consecutive snake activity seasons. I quantified the snake species richness, Shannon diversity, and Shannon equitability for the snake community in …