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Full-Text Articles in Ecology and Evolutionary Biology

The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten May 2024

The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten

Electronic Theses and Dissertations

Raccoons (Procyon lotor) are a dominant predator of American alligator (Alligator mississippiensis) nests in the southeastern United States, using a combination of olfactory, visual, and tactile cues to identify nest locations. Studies on alligator nesting ecology typically require researchers to create paths through marsh habitat, potentially introducing visual and olfactory cues raccoons may use to locate nests. The purpose of this study was to evaluate the effect of human visitation to alligator nests on the frequency of raccoon nest predation at two sites in coastal South Carolina, Tom Yawkey Wildlife Center (TYWC) and Santee Coastal Reserve (SCR). We hypothesized that …


Screening H3 Histone Acetylation In A Wild Bird, The House Sparrow (Passer Domesticus), Daniella Ray Jan 2024

Screening H3 Histone Acetylation In A Wild Bird, The House Sparrow (Passer Domesticus), Daniella Ray

Electronic Theses and Dissertations

Epigenetic mechanisms are increasingly understood to have major impacts across ecology. However, one molecular epigenetic mechanism, DNA methylation, currently dominates the literature. A second mechanism, histone modification, is likely important to ecologically relevant phenotypes and thus warrants investigation, especially because molecular interplay between methylation and histone acetylation can strongly affect gene expression. There are a limited number of histone acetylation studies on non-model organisms, yet those that exist show that it can impact gene expression and phenotypic plasticity. Wild birds provide an excellent system to investigate histone acetylation, as free-living individuals must rapidly adjust to environmental change. Here, we screen …


Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil Dec 2023

Breaking Virulent: The Coincidental Evolution Of Virulence Factors In Bacteria., Rhiannon Emmanuelle Cecil

Electronic Theses and Dissertations

Understanding how innocuous organisms can evolve to be pathogenic to humans is of increasing global concern. Further, understanding how existing pathogens may evolved to be more virulent is also vital to our ability to provide healthcare to people afflicted with diseases that promote chronic bacterial infections, such as cystic fibrosis. With the rise of antibiotic resistance in both bacteria and fungi it is paramount that new therapeutics are identified. Understanding what mutations occur that result in increased virulence in microbes can potentially provide new targets for antimicrobial drugs to combat antibiotic resistance. The Coincidental Evolution Hypothesis is a fundamental hypothesis …


Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson Aug 2023

Effects Of Large Wood Additions On Basal Resources, Macroinvertebrates, And Ecosystem Processes In The Narraguagus River, Maine, Val Watson

Electronic Theses and Dissertations

Ecological restoration is an increasingly common practice across ecosystems, and current practices aim to restore the biological and physical processes underlying ecosystem function, often for the sake of endangered higher-level consumers. Studies of restoration outcomes often report few or inconsistent ecological changes, and monitoring of restoration projects rarely measures ecological processes. Monitoring also usually measures outcomes at a single scale, despite the prevalence of scale- dependent phenomena across ecosystems. My thesis uses measurements of ecological processes to assess restoration response and evaluates responses across multiple scales. I focus here on a long-term large wood addition project on the Narraguagus River …


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 …


Comparative Energetics Of Mammalian Thermoregulatory Physiology, Ana M. Breit May 2023

Comparative Energetics Of Mammalian Thermoregulatory Physiology, Ana M. Breit

Electronic Theses and Dissertations

Endothermy allows species to decouple body temperature from environmental
temperatures but does not equate to endothermic species maintaining those constant temperatures. Instead, heterothermy fluctuating body temperatures, both in and outside of torpor is common and allows endotherms to expand the limits of thermoneutrality. Thermolability is likely to be more common in the tropics and subtropics, where species live within or above their thermoneutral zone. My dissertation research focused on the heterothermic-homeothermic continuum, specifically quantifying where on the continuum different species fall at certain times and why those species have evolved to be at those points. I quantified the thermal profile …


Neonate Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) Relative Abundance And Body Condition In Two South Carolina Estuaries Varying In Urbanization, Rileigh E. Hawk May 2023

Neonate Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) Relative Abundance And Body Condition In Two South Carolina Estuaries Varying In Urbanization, Rileigh E. Hawk

Electronic Theses and Dissertations

Urbanization near estuaries has been shown to affect the growth and survival of juvenile sharks using the system as a nursery. North Inlet and Murrells Inlet, South Carolina, are similarly-sized, tidally-dominated, bar-built estuaries with extensive Sporobolus-lined tidal creeks but differ in degree of human impact. Previously, Murrells Inlet was shown to have a lower abundance and diversity of large sharks than North Inlet and Atlantic Sharpnose Sharks (Rhizoprionodon terraenovae) were shown to use North Inlet as a primary nursery. To examine potential differences in neonate shark abundance and growth between a developed estuary, Murrells Inlet, and a protected estuary, North …


Vibroacoustic Response Of The Tympanic Membrane To Hyoid-Borne Sound Generated During Echolocation In Bats, Chelsie Snipes May 2023

Vibroacoustic Response Of The Tympanic Membrane To Hyoid-Borne Sound Generated During Echolocation In Bats, Chelsie Snipes

Electronic Theses and Dissertations

The hyoid apparatus in laryngeally echolocating bats forms a mechanical connection between the larynx and auditory bullae and has been hypothesized to transfer the outgoing echolocation call to the middle ear during echolocation call emission. We used µCT data to build models of the hyoid apparatus and middle ear from six species of bats and used finite element modeling (FEM) to measure the vibroacoustic response of the tympanic membrane due to hyoid-borne sound generated during echolocation. We found that hyoid-borne sound in all six species stimulated the eardrum within a range likely heard by bats. Although there were minor differences …


C3 And C4 Grass Dominated Plant Communities Differ In Response To Future Larger And Less Frequent Rainfall, Zigeng Chen Jan 2023

C3 And C4 Grass Dominated Plant Communities Differ In Response To Future Larger And Less Frequent Rainfall, Zigeng Chen

Electronic Theses and Dissertations

Climate change is leading to larger and less frequent rainfall in the Northern Great Plains (NGP). We ask if this change in rainfall would influence carbon (C) and nitrogen (N) cycling in the NGP. First, we collected soils from C3 and C4 grass dominated plant communities from western South Dakota and conducted an incubation experiment to explore the effects of soil water content (SWC) and temperature on soil respiration (Rs) and N mineralization rate (ΔIN). Second, we conducted a three-year rainfallmanipulation (RaMP) experiment with two distinct rainfall regimes (frequent/small and infrequent/large events with constant total monthly precipitation) and two grasses …


Fine-Scale Site Selection Of Strand-Feeding Common Bottlenose Dolphins (Tursiops Truncatus) And Their Prey, Deborah Kleinclaus Dec 2022

Fine-Scale Site Selection Of Strand-Feeding Common Bottlenose Dolphins (Tursiops Truncatus) And Their Prey, Deborah Kleinclaus

Electronic Theses and Dissertations

Strand-feeding is a unique, cooperative foraging strategy used by some common bottlenose dolphins (Tursiops truncatus) at low tide in South Carolina and Georgia salt marshes, where a group of dolphins charges schools of fish, thrusting them onto the bank with their bow wave and then capturing prey items onshore. Strand-feeding dolphins are estuarine residents and frequent predictable stranding sites, suggesting an intimate knowledge of the area. Dolphin behavior prior to stranding suggests they do not herd the fish before charging, but instead prey on fish already shoaling near the bank. The use of active acoustics from strand-feeders in order to …


Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman Dec 2022

Importance Of The Microhabitat And Microclimate Conditions In The Northern Gray-Cheeked Salamander (Plethodon Montanus) Across An Elevation Gradient, Trevor Chapman

Electronic Theses and Dissertations

The southern Appalachian Mountains have among the highest salamander diversity in the world, largely due to local speciation in the family Plethodontidae. Plethodontid salamanders (i.e., lungless salamanders) are particularly sensitive to habitat climate conditions due to their reliance on cutaneous respiration, and their immediate environmental conditions (microhabitat) likely influence their dispersion and activity more than the large-scale atmospheric conditions. The Northern Gray-cheeked salamander (Plethodon montanus) is restricted to high elevations in the Appalachian Mountains. Our goal was to investigate the relationship between P. montanus and its microhabitat by examining behavioral preference for climatic conditions, characterizing the microclimate with …


A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig May 2022

A Review Of Current Methods In Avian Dietary Analysis And Their Integrated Application To Characterize The Trophic Niche Of Louisiana Waterthrush (Parkesia Motacilla)., Brandon Hoenig

Electronic Theses and Dissertations

Characterizing a species’ dietary composition presents an avenue to understand many facets of its ecological niche and can provide essential information for the species’ long-term conservation. To date, the vast majority of diet studies have relied on direct identification of prey during foraging observations or from diet samples to characterize the dietary habits of birds. However, advancements in laboratory-based approaches have revolutionized the field of trophic ecology by allowing researchers to indirectly infer dietary habits with higher resolution across greater time scales. Here, I apply two of these laboratory-based techniques, namely DNA metabarcoding and stable isotope analysis, to characterize the …


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 …


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 …


Environmental Gradients Impact Key Leaf Traits In Riparian Trees, Amanda Malone Jan 2022

Environmental Gradients Impact Key Leaf Traits In Riparian Trees, Amanda Malone

Electronic Theses and Dissertations

Specific leaf area (SLA) reflects a plant’s carbon investment per area and relates to generalized leaf economics spectrum growth strategies (LES). To fill gaps of knowledge about intraspecific SLA variation and why it is often inconsistent with the LES, we studied the response of two riparian tree species along the urban-rural gradient in Northeastern Colorado: an invasive, nitrogen-fixer with broad tolerances and a nitrogen-limited and shade-intolerant native. Despite these differences, the two species responded similarly, apart from the response to the urban-rural gradient, in which lower nitrogen in rural areas was associated with a more conservative strategy in the native …


Targeted Browsing With Goats For Eastern Redcedar (Juniperus Virginiana L.) Control, Alanna M. Hartsfield Jan 2022

Targeted Browsing With Goats For Eastern Redcedar (Juniperus Virginiana L.) Control, Alanna M. Hartsfield

Electronic Theses and Dissertations

As eastern redcedar (ERC) (Juniperus virginiana L.) grassland encroachment progresses, all potential control methods should be explored in the interest of Great Plains grassland health and longevity. Targeted browsing with goats has been proven as an effective control method on some juniper species; however, little is known about its ability to control ERC. These studies intend to mend knowledge gaps of how targeted browsing with goats control ERC by causing tree death without chemicals or machinery. The first study is two 3x3 Latin squares comparing protein-supplemented diets. The second study is a randomized complete block design of five 0.224 ha …


Stop, Then Go! Rapid Acceleration Offsets The Costs Of Intermittent Locomotion When Turning In Florida Scrub Lizards, Cheyenne Walker Jan 2022

Stop, Then Go! Rapid Acceleration Offsets The Costs Of Intermittent Locomotion When Turning In Florida Scrub Lizards, Cheyenne Walker

Electronic Theses and Dissertations

Intermittent locomotion is a commonly used escape strategy with a wide array of potential benefits. Pausing may aid in locating a predator, crypsis, lowering energy costs, and avoiding obstacles. Turning may also benefit from intermittent locomotion by allowing an animal time to assess its surroundings; therefore, decreasing the chances of making a mistake and/or stumbling. Florida scrub lizards live in environments with a variety of obstacles such as turns. The goal of this study is to quantify the locomotor behavior and performance by lizards while navigating a 45° or 90° turn. Lizards were run along both a 45° and 90° …


Mortality In Interspecific Hybrids Of Nasonia Vitripennis And Nasonia Giraulti, Bonnie Cobb Jan 2022

Mortality In Interspecific Hybrids Of Nasonia Vitripennis And Nasonia Giraulti, Bonnie Cobb

Electronic Theses and Dissertations

Nasonia is a parasitoid wasp genus that serves as an emerging model for studying speciation due to an incompatibility between nuclear and mitochondrial genomes between sister taxa. Short generation times, easy rearing in a lab setting, producing large amounts of progeny, and whole genome sequencing make Nasonia is an excellent candidate for studying incomplete reproductive isolation. Nasonia have five chromosomes and exhibit haplo-diploid sex determination in which fertilized eggs develop into diploid females and unfertilized eggs develop into haploid males. Recessive phenotypes are hidden in diploid females but are laid bare in haploid males as there is no interaction between …


Does It Take A Community To Save A Species? Examining The Use Of Community Interactions To Restore Unionid Species At Risk, Roland Adriaan Eveleens Oct 2021

Does It Take A Community To Save A Species? Examining The Use Of Community Interactions To Restore Unionid Species At Risk, Roland Adriaan Eveleens

Electronic Theses and Dissertations

The conservation and restoration of freshwater ecosystems are complex. Knowledge from community ecology, conservation biology, and restoration ecology was integrated to interrogate the role of species interactions involving freshwater mussels (order Unionida) as keystone species. Freshwater mussels require host fish and provide ecosystem functions for other species throughout aquatic and riparian ecosystems, yet conservation efforts remain focused on focal mussel species or host fish associations. My thesis explored species co-occurrences within mussel and benthic macroinvertebrate community assemblages, and systematically reviewed the published literature to assess the breadth and reported effectiveness of mussel restoration. Community analyses confirmed species co-occurrences across environmental …


Parasites And Sexual Selection In A Sexually Dichromatic Toad, Nicole Erin Shangi Oct 2021

Parasites And Sexual Selection In A Sexually Dichromatic Toad, Nicole Erin Shangi

Electronic Theses and Dissertations

Parasitism is among the most common and successful life history strategies on Earth, leading to constant coevolution between parasites and hosts. Parasites continuously pressure hosts to evolve more effective parasite resistance, fueling interest in the relationships between expression of sexually selected host ornamentation and parasite resistance. By studying parasite-mediated sexual selection we gain unique insights into the evolution of animal traits. In this thesis, I attempt to further our understanding of a sexually dichromatic neotropical anuran by studying its parasites in the context of sexual selection. Firstly, in the General Introduction (Chapter 1), I reviewed important background information key to …


The Function And Evolution Of Wood-Warbler Flight Calls (Parulidae), Zach G. Gayk Oct 2021

The Function And Evolution Of Wood-Warbler Flight Calls (Parulidae), Zach G. Gayk

Electronic Theses and Dissertations

Animals produce vocalizations to communicate with territorial rivals, to communicate with potential mates, to alert others of predators, or to stay in contact with other animals. To date, little research has focused on the vocalizations that animals use to communicate during migration. Many birds produce flight calls, which are short calls given by migratory birds on the wing. The function of flight calls is poorly understood but they are thought to help migrants maintain contact with other individuals during movements between breeding grounds and wintering grounds. Across four data chapters in my dissertation, I investigated the function and evolution of …


Using Predator Vocalizations To Deter Raccoon Predation On Nests Of Diamondback Terrapins (Malaclemys Terrapin), Colleen Elizabeth Naeger Aug 2021

Using Predator Vocalizations To Deter Raccoon Predation On Nests Of Diamondback Terrapins (Malaclemys Terrapin), Colleen Elizabeth Naeger

Electronic Theses and Dissertations

No abstract provided.


Examining The Links Between Environmental Variation, Foraging Behaviour And Foraging Success In An Arctic Seabird, Alyssa Eby Jul 2021

Examining The Links Between Environmental Variation, Foraging Behaviour And Foraging Success In An Arctic Seabird, Alyssa Eby

Electronic Theses and Dissertations

Arctic regions are experiencing increasing variability in inter-annual sea ice dynamics ultimately impacting marine Arctic ecosystems. Arctic-breeding seabirds, such as thick-billed murres (Uria lomvia) are thus likely to be negatively impacted by fluctuating environmental conditions through its influence on prey availability. Additional extrinsic factors (colony size and chick demand) and intrinsic factors (sex) are also likely to impact foraging behaviour and success of murres in combination with environmental conditions. First, we tested the effect of colony size on colony sensitivity to environmental change at two low Arctic colonies of varying sizes, Coats Island, Nunavut and Digges Island, Nunavut …


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 …


Understanding Patterns And Functional Impacts Of An Invasive Tree And Its Biological Control In A Riparian System, Annie L. Henry Jan 2021

Understanding Patterns And Functional Impacts Of An Invasive Tree And Its Biological Control In A Riparian System, Annie L. Henry

Electronic Theses and Dissertations

Invasive species have become an inextricable part of the landscape, particularly in riparian plant communities, and removal is often a key component of restoration programs. Biological control (biocontrol) is a method of removal that is often both efficient and effective. However, the impact of biocontrol on target species and indirect effects from invasive species removal can be hard to predict. While monitoring the impact of invasive species removal usually involves some species-based assessment such as changes in diversity, historically dominant species or native species, these strategies do not typically provide insight into the mechanisms underlying plant community response to removal. …


Predation Threat In A Variable Landscape: Connecting Predation Risk To Nesting Success For The Seaside Sparrow (Ammospiza Maritima Macgilivraii), Corina D. Newsome Jan 2021

Predation Threat In A Variable Landscape: Connecting Predation Risk To Nesting Success For The Seaside Sparrow (Ammospiza Maritima Macgilivraii), Corina D. Newsome

Electronic Theses and Dissertations

Predation, the leading cause of nest-failure in birds, not only exists as a direct threat to nesting success, but may exacerbate other sources of nest mortality. Birds inhabiting Atlantic coastal marshes, such as Seaside Sparrows (Ammospiza maritima; hereafter SESP), are experiencing significant and rapid changes to their habitat, particularly sea level rise (SLR) and encroaching urbanization, that may affect the relative influence of nest predation on overall productivity. For SESPs, SLR presents an inherent threat to nest success in its potential to increase the frequency of nest flooding. In addition to this direct threat, the ability of SESPs …


Pollinator Ecology In Agroecosystems Of Eastern South Dakota, Isabela Beatriz Vilella-Arnizaut Jan 2021

Pollinator Ecology In Agroecosystems Of Eastern South Dakota, Isabela Beatriz Vilella-Arnizaut

Electronic Theses and Dissertations

Community structure contributes to ecosystem persistence and stability. To understand the mechanisms underlying pollination and community stability of natural areas in a human influenced landscape, a better understanding of the interaction patterns between plants and pollinators in disturbed landscapes is needed. Furthermore, understanding the potential conservation value in green spaces such as botanical gardens could assist in preserving and bolstering plant-pollinator interactions. Our study takes place in the Northern Great Plains which still retains extensive tracts of remnant temperate grassland habitat within a matrix of varying land-uses. First, we used a network-based approach to quantify how temperate grassland attributes and …


Residency, Diel Movement, And Tidal Patterns Of Large Juvenile Bull Sharks (Carcharhinus Leucas) In Winyah Bay, Sc, Jeremy Lee Arnt Dec 2020

Residency, Diel Movement, And Tidal Patterns Of Large Juvenile Bull Sharks (Carcharhinus Leucas) In Winyah Bay, Sc, Jeremy Lee Arnt

Electronic Theses and Dissertations

No abstract provided.


Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo Aug 2020

Distributions And Abundances Of The Red Tide Dinoflagellate Alexandrium Catenella In The Eastern Gulf Of Maine And Bay Of Fundy In Relation To Diatoms In June, July And August Of 2019, Kimberly Lina D'Adamo

Electronic Theses and Dissertations

A series of three oceanographic survey cruises were conducted in June, July, and August of 2019 in the northeastern Gulf of Maine and Bay of Fundy. Surface water samples were collected and analyzed for enumerations of cell densities of the dinoflagellate Alexandrium catenella in relation to cell densities of diatoms. Hydrographic profiles of temperature, salinity, and nutrients (silicate and nitrate) were also made at each station. Data were analyzed to determine if there was any statistically significant evidence of allelopathic interference imparted by diatoms that impede A. catenella. A. catenella cells were most abundant in June, reaching 6,195 cells per …