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Full-Text Articles in Biology

The Interplay Of The Physical Landscape And Social Dynamics In Shaping Movement Of African Savanna Elephants (Loxodonta Africana), Maggie Wisniewska Aug 2021

The Interplay Of The Physical Landscape And Social Dynamics In Shaping Movement Of African Savanna Elephants (Loxodonta Africana), Maggie Wisniewska

Dissertations

Free ranging African savanna elephants (Loxodonta africana) are increasingly impacted by human-induced habitat loss and poaching for ivory. Because elephants live in tightly knit groups, this combination of threats not only reduces the size of their populations but also degrades their social interactions. Long-term relationships with socially competent individuals, such as experienced seniors, benefit the ability of other group members to access limiting resources and avoid danger. Understanding how anthropogenic pressure may affect persistence of elephant populations is important, because elephants are an economically important keystone species. This doctoral thesis characterizes how individual elephants influence the movement of their social …


Zooarchaeology And Taphonomic Aspects Of Later Stone Age Faunal Assemblage From Loiyangalani Site In Serengeti National Park, Tanzania, Frank Masele Aug 2021

Zooarchaeology And Taphonomic Aspects Of Later Stone Age Faunal Assemblage From Loiyangalani Site In Serengeti National Park, Tanzania, Frank Masele

Tanzania Journal of Science

The paper presents detailed zooarchaeological and taphonomic results on the Later Stone Age (LSA) faunal assemblage. The contributions of various taphonomic agents in the formation of the assemblage are accentuated. The assemblage is well-preserved and the majority of specimens are not highly weathered. Fluvial disturbance did not play a significant role and can be ruled out as a significant taphonomic agent in the formation. Results indicate that LSA humans exploited high-quality nutritional resources mainly of the large-sized animals and aquatic resources as extra sources of meat and fat. The assemblage preserves stone tools butchery marks (cut marks and percussion marks) …


Is The Life History Flexibility Of Cold Desert Annuals Broad Enough To Cope With Predicted Climate Change? The Case Of Erodium Oxyrhinchum In Central Asia, Huiliang Liu, Yanfeng Chen, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Lan Zhang, Yan Liu, Daoyuan Zhang, Yuanming Zhang Aug 2021

Is The Life History Flexibility Of Cold Desert Annuals Broad Enough To Cope With Predicted Climate Change? The Case Of Erodium Oxyrhinchum In Central Asia, Huiliang Liu, Yanfeng Chen, Lingwei Zhang, Jerry M. Baskin, Carol C. Baskin, Lan Zhang, Yan Liu, Daoyuan Zhang, Yuanming Zhang

Biology Faculty Publications

Interannual seasonal variability in precipitation may strongly affect the life history and growth of desert annual plants. We compared the effects of dry and wet springs and dry and wet autumns on growth and F2 seed dormancy of plants from spring (SG)- and autumn (AG)-germinated seeds of the cold desert annual Erodium oxyrhinchum. Vegetative and reproductive growth and F2 seed dormancy and germination were monitored from September 2016 to November 2020 in the sandy Gurbantunggut Desert in NW China in Central Asia. Dry autumns decreased the density of AG plants, and dry springs decreased the density of SG plants …


Assessing The Short-Term Effects Of Translocation On Freshwater Mussels: Is Habitat Or Water Quality More Important?, Joshua D. Arnold Aug 2021

Assessing The Short-Term Effects Of Translocation On Freshwater Mussels: Is Habitat Or Water Quality More Important?, Joshua D. Arnold

Masters Theses

Freshwater mussels (Order: Unionida) are very important to the function of aquatic ecosystems and are typically indicators of good water quality. They provide a valuable link between the water column and the benthic substrate in which they live and are a valuable food resource for many species of animals. However, most species native to North America are currently threatened with extinction, to the point that more than 70% of native freshwater mussels are listed as either threatened or endangered at the state or federal level. The cause of this decline can be attributed to historical over exploitation, habitat alteration, and …


Is Immediate Flexibility Present In A Vocal Mimic, The Gray Catbird (Dumetella Carolinensis), Across An Urban Gradient?, Shannon K. Eppert Aug 2021

Is Immediate Flexibility Present In A Vocal Mimic, The Gray Catbird (Dumetella Carolinensis), Across An Urban Gradient?, Shannon K. Eppert

Masters Theses, 2020-current

Increasing urbanization has increased anthropogenic noise levels near developed areas. Urban noise is high amplitude and low-frequency, and these frequencies can overlap with the signals animals use to communicate, including bird songs. Many urban birds sing higher minimum frequencies in urban areas, which avoids some masking by noise, but the mechanism behind this difference is not well understood. Immediate flexibility is the ability to alter song in real-time in the presence of sudden noise, allowing for avoidance of masking and better signal transmission. I investigated if male catbirds increased signal transmission in the presence of anthropogenic versus high-frequency noise playback …


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.


Long-Term Crop Rotation Diversification Enhances Maize Drought Resistance Through Soil Organic Matter, Leah L.R. Renwick, William Deen, Lucas Silva, Matthew E. Gilbert, Toby Maxwell, Timothy M. Bowles, Amélie C.M. Gaudin Aug 2021

Long-Term Crop Rotation Diversification Enhances Maize Drought Resistance Through Soil Organic Matter, Leah L.R. Renwick, William Deen, Lucas Silva, Matthew E. Gilbert, Toby Maxwell, Timothy M. Bowles, Amélie C.M. Gaudin

Biology Faculty Publications and Presentations

Climate change adaptation requires building agricultural system resilience to warmer, drier climates. Increasing temporal plant diversity through crop rotation diversification increases yields of some crops under drought, but its potential to enhance crop drought resistance and the underlying mechanisms remain unclear. We conducted a drought manipulation experiment using rainout shelters embedded within a 36-year crop rotation diversity and no-till experiment in a temperate climate and measured a suite of soil and crop developmental and eco-physiological traits in the field and laboratory. We show that diversifying maize-soybean rotations with small grain cereals and cover crops mitigated maize water stress at the …


Pedigree And Molecular Assessment Of Relatedness In A Captive Chimpanzee Population, Francesca Golus Aug 2021

Pedigree And Molecular Assessment Of Relatedness In A Captive Chimpanzee Population, Francesca Golus

Masters Theses

As a crucial component of biodiversity, genetic diversity contributes to variability among individuals, allowing populations of endangered species to be resilient in the face of changing environmental conditions. Zoological institutions have become a cornerstone of conservation efforts and a refuge for endangered species given threats imposed on wild populations by climate change, habitat fragmentation and degradation, and overexploitation. Chimpanzees (Pan troglodytes) are an endangered species experiencing drastic population decline in the wild, yet are common residents in zoos and wildlife sanctuaries. To sustain long-term, genetically viable populations of species of concern, zoos use studbooks and paternity testing to …


Ecological Correlates Of Alligator Snapping Turtle Bite Performance, Ashley Herrin Gagnon Aug 2021

Ecological Correlates Of Alligator Snapping Turtle Bite Performance, Ashley Herrin Gagnon

Graduate Theses/Dissertations

The Alligator Snapping Turtle (Macrochelys temminckii) is one of many turtle species facing conservation challenges. Nearly extirpated in the 1980s, it is currently the subject of a head-start initiative, of which, any lasting behavioral or physiological effects were—until now—unknown! To evaluate the ability of captive-reared individuals to excel in natural habitats, and to foresee any future research or conservation challenges regarding this animal, I explored a suite of variables that influence bite performance and behaviors including captive or free-ranging status, and environmental conditions including body temperature and season. My results indicated that free-ranging M. temminckii outperform those residing …


Investigation Into The Evolution Of Heterogeneity Within Secondary Replicons And Their Maintenance In Genus Variovorax, Christopher Ne Ville Aug 2021

Investigation Into The Evolution Of Heterogeneity Within Secondary Replicons And Their Maintenance In Genus Variovorax, Christopher Ne Ville

Electronic Theses, Projects, and Dissertations

Approximately 10% of all bacterial genomes sequenced thus far contain a secondary replicon. This considerable genetic reservoir contains many potentially mobilizable elements, allowing for the formation of many unique secondary replicons. This property of bacterial populations vastly increases the genomic diversity available to species that effectively take up and maintain these replicons. Members of the genus Variovorax have extensive heterogeneity in genome architecture, including sequenced isolates containing plasmids, megaplasmids, and chromids. Using available Illumina data on the NCBI database, we have completed these assemblies using 3rd generation sequencing methods on 17 members of this genus. We have sequenced, assembled, …


Analyzing Genetic Variation Of The Tussock Cottongrass Among Ecotypes Along A Latitudinal Gradient Through Transcriptomics, Carmen Webster Aug 2021

Analyzing Genetic Variation Of The Tussock Cottongrass Among Ecotypes Along A Latitudinal Gradient Through Transcriptomics, Carmen Webster

Open Access Theses & Dissertations

The Arctic is seeing some of the most extreme effects of climate change that induce environmental pressures, including warmer temperatures and longer growing seasons. Due to this, taxa may need to adapt or migrate in order to survive. The long-lived tussock cottongrass, Eriophorum vaginatum, is a foundation species in the Arctic, and little is currently known about the genetic constraints that could be playing a role in how this species will respond to the changing climate. Specific gene families that play an important role in signaling genetic pathways related to plant phenology and response to environmental stress are likely to …


Empowering Hope-Based Climate Change Communication Techniques For The Gulf Of Maine, Aimee Bonanno, Megan Ennes, Jennifer A. Hoey, Emily Moberg, Sarah-Mae Nelson, Nette Pletcher, Richelle L. Tanner Jul 2021

Empowering Hope-Based Climate Change Communication Techniques For The Gulf Of Maine, Aimee Bonanno, Megan Ennes, Jennifer A. Hoey, Emily Moberg, Sarah-Mae Nelson, Nette Pletcher, Richelle L. Tanner

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The Gulf of Maine is one of the fastest warming marine areas on the planet: The industries and creatures that call it home face an unprecedented shift in their interactions and existence. Scientists, policy makers, and practitioners often want to communicate to the public about the seriousness of the situation to encourage mitigation and adaptation. Many standard communication strategies that rely on fear and scientific authority alone—rather than comprehensive explanations that include solutions—can leave audiences feeling overwhelmed and disengaged, instead of hopeful and motivated to act. In this practice bridge, we showcase a social science research-based climate change communication “tool-kit” …


Phragmites Australis Dieback In The Mississippi River Delta: Chemical Profiles Of Soil Types And Restoration Potential, Herie Lee Jul 2021

Phragmites Australis Dieback In The Mississippi River Delta: Chemical Profiles Of Soil Types And Restoration Potential, Herie Lee

LSU Master's Theses

Since 2016, there has been widespread dieback of P. australis in the Lower Mississippi River Delta (hereafter referred to as Lower MRD, which is defined as the Birds Foot Delta) with relatively little to no signs of recovery. The cause of the current dieback is not fully understood. This thesis explores P. australis with emphasis on chemical profile characterization of different soil types and its effects on plant growth and the potential for restoration in the Lower MRD.

In chapter 2, I characterized the chemical profiles of soils collected from healthy and dieback stands of Phragmites, and from newly …


Neurotranscriptomic Changes Associated With Chick-Directed Parental Care In Adult Non-Reproductive Japanese Quail, Patricia C. Lopes, Robert De Brujin Jul 2021

Neurotranscriptomic Changes Associated With Chick-Directed Parental Care In Adult Non-Reproductive Japanese Quail, Patricia C. Lopes, Robert De Brujin

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

For many species, parental care critically affects offspring survival. But what drives animals to display parental behaviours towards young? In mammals, pregnancy-induced physiological transformations seem key in preparing the neural circuits that lead towards attraction (and reduced-aggression) to young. Beyond mammalian maternal behaviour, knowledge of the neural mechanisms that underlie young-directed parental care is severely lacking. We took advantage of a domesticated bird species, the Japanese quail, for which parental behaviour towards chicks can be induced in virgin non-reproductive adults through a sensitization procedure, a process that is not effective in all animals. We used the variation in parental responses …


Investigating Local Adaptation To Hypoxia Stress In The Eastern Oyster Through Comparative Transcriptomics, Heather Nichole Smith Jul 2021

Investigating Local Adaptation To Hypoxia Stress In The Eastern Oyster Through Comparative Transcriptomics, Heather Nichole Smith

LSU Master's Theses

Climate change represents one of the most important challenges to biodiversity, therefore it is important to understand the mechanisms that allow species to respond to rapid environmental change. Here, we compared two populations of eastern oysters, Crassostrea virginica, from the Gulf of Mexico to study the mechanisms underlying hypoxia tolerance. Using a common garden experiment and comparative transcriptomics, we identified sets of genes involved in the hypoxia response and found differences in both the timing and baseline expression of hypoxia-responsive genes between tolerant and sensitive populations, consistent with a scenario of local adaptation. These genes include the signaling transcription factor …


Enhancing Existing Isolated Underpasses With Fencing Reduces Wildlife Crashes And Connects Habitat, Bridget M. Donaldson, Kaitlyn E. M. Elliott Jul 2021

Enhancing Existing Isolated Underpasses With Fencing Reduces Wildlife Crashes And Connects Habitat, Bridget M. Donaldson, Kaitlyn E. M. Elliott

Human–Wildlife Interactions

The impact of wildlife–vehicle collisions on drivers and wildlife populations has been gaining attention in the United States. Given the established success of wildlife crossings with fencing in reducing wildlife crashes and connecting habitat, information is needed on cost-effective means of implementation for departments of transportation. When wildlife crossings are constructed, they are often built into new road projects as a series of 2 or more underpasses and/or overpass structures connected by exclusionary fencing. Given limited transportation budgets and the prevalence of maintenance activities more so than new construction in many states, enhancing existing underpasses on previously constructed roads has …


Zygomorphic Flowers May Reduce Extinction Rates By Allowing Angiosperms To Occur In Low Abundances, Maria Belen Alvestegui Jul 2021

Zygomorphic Flowers May Reduce Extinction Rates By Allowing Angiosperms To Occur In Low Abundances, Maria Belen Alvestegui

Theses

The high species richness that angiosperm show has been extensively correlated with key floral innovations. Key floral traits contribute to species boundaries and the origin of new species. However, how these relate to extinction remains largely untested. Among the multiple theories that attribute diversification to floral innovations, the reduced extinction model predicts that floral specialization allows the persistence of small populations and avoids their loss. Bilateral symmetry (zygomorphy) is a trait that has evolved recurrently in angiosperms. It is a form of floral specialization that restricts pollination to fewer visitors and precisely places pollen to ensure more effective transmission of …


Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam Jul 2021

Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam

LSU Master's Theses

Eastern oysters (Crassostrea virginica) provide valuable ecosystem services and support a productive commercial industry in the northern Gulf of Mexico. Declining abundance from water quality changes and other factors drives development of management and restoration strategies focused on a comprehensive, metapopulation approach. Identifying oyster resource zones based on water quality combined with selective breeding of oysters adapted to specific conditions provides strategies to support aquaculture development and ensure resilient oyster populations and high production. Using 2015-2019 satellite-derived continuous salinity and temperature data for coastal Louisiana, this work created maps defining oyster resource zones supportive of (1) broodstock sanctuary …


Of Biodiversity, Boundaries, And Distribution: The Myxomycetes Of The Philippines And Beyond, Sittie Aisha Bustamante Macabago Jul 2021

Of Biodiversity, Boundaries, And Distribution: The Myxomycetes Of The Philippines And Beyond, Sittie Aisha Bustamante Macabago

Graduate Theses and Dissertations

This dissertation contains a compilation of independently performed studies primarily focusing on the myxomycetes (plasmodial slime molds) from the Philippines and integrating local and worldwide data to demonstrate regional and global trends. The major themes include the following: (I) a review of the diverse group of spore-producing amoeboid protists, including the myxomycetes; (II-IV) diversity assessments in three different groups of islands in the Philippine archipelago; (V) mapping the myxomycetes found in the Philippines for databasing and analyzing the geocoded data; (VI) a study on regional boundaries, including the Philippines, using myxomycete species composition; and, (VII) creating a global species distribution …


Yakety Sacs: Laryngeal Air Sac Usage In Great Apes, Chelsea Trenbeath Jun 2021

Yakety Sacs: Laryngeal Air Sac Usage In Great Apes, Chelsea Trenbeath

Master of Science in Integrative Biology Theses

Except for humans, extant great apes have evolutionarily conserved lateral ventricular air sacs extending from laryngeal saccules. Humans are the only species of Hominidae that lack this anatomical feature attached to the primary vocal apparatus. As we are the only species that produces spoken language, this association has led to the hypothesis that the loss of lateral ventricular air sacs was necessary for the evolution of spoken language. However, why these sacs are conserved in all other hominids remains unclear. Computer modeling has indicated that air sacs may increase resonance properties, but there are no data from great apes indicating …


Spiders You May Encounter While Social Distancing: A Field Guide To Oregon, Daniel K. Hufnagel Jun 2021

Spiders You May Encounter While Social Distancing: A Field Guide To Oregon, Daniel K. Hufnagel

Anthós

This document is simply a short field guide on the many endearing spiders you have encountered or will potentially encounter while social distancing in Oregon. Included are journal entries for six different species of spider, with each log containing an illustration and a description of the physical appearance, behavior, and habitat of the arachnid listed. Also included is a basic diagram depicting the anatomy of the common spider.


Covid-19: A One Health Issue, Karen Gruszynski Jun 2021

Covid-19: A One Health Issue, Karen Gruszynski

Cumberland Mountain Naturalist

COVID-19 has very rapidly become part of modern societal lexicon as the disease highlights the importance understanding zoonotic diseases and the impact they can have on human life. With a 177million human cases and 3.82million deaths globally at the time of this publication, the "One Health" nature of the disease has had a lasting impact across the planet. As the disease spread rapidly, it highlighted the dissemination of information through social media and other sources. With this in mind, Dr. Gary Vroegindewey, Director for One Health at LMU-CVM, put forth the idea to have students collect and summarize information about …


Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis Jun 2021

Rapid Warming Events In A Small Coastal Upwelling Embayment, Tatjana E. Ellis

Physics

Temperature variability in the nearshore coastal ocean influences various biological processes and can drive changes in biodiversity and habitat range. Despite recent progress, there are still significant gaps in the understanding of drivers of temperature variability in upwelling bays, particularly at higher frequencies. In this study, we analyzed a decade of nearshore temperature measurements both inside and outside a small coastal embayment located in central California [San Luis Obispo (SLO) bay], as well as temperature data from satellites, to characterize rapid warming events. We found that rapid warming events, defined using rates of temperature change across different thresholds, occurred more …


Longitudinal Study Of Pogonomyrmex Occidentalis (Hymenoptera: Formicideae), Western Harvester Ant, Colony Survival In Western Nebraska, Kathleen H. Keeler Jun 2021

Longitudinal Study Of Pogonomyrmex Occidentalis (Hymenoptera: Formicideae), Western Harvester Ant, Colony Survival In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

I observed individual western harvester ant (Pogonomyrmex occidentalis) colonies, marked between 1977 and 1994, to live a mean of 15.65 years (n = 112). The longest-lived colony lived 42 years.


Linking Behavioral States To Landscape Features For Improved Conservation Management, Maitreyi Sur, Jim R. Belthoff Jun 2021

Linking Behavioral States To Landscape Features For Improved Conservation Management, Maitreyi Sur, Jim R. Belthoff

Biology Faculty Publications and Presentations

  1. A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat-specific behaviors.
  2. Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila chrysaetos) in the Sonoran and Mojave Deserts of the southwestern United States, and we identify, for each behavioral state, conservation-relevant habitat associations.
  3. We modeled behavior using 186,859 GPS points from 48 eagles and identified 2,851 distinct segments comprising four behavioral states. Altitude above ground level (AGL) best differentiated behavioral states, …


A Dynamic Landscape Of Fear: Human Impacts On Carnivore Communities, Tru Hubbard Jun 2021

A Dynamic Landscape Of Fear: Human Impacts On Carnivore Communities, Tru Hubbard

All NMU Master's Theses

Mammalian carnivores are elusive, enigmatic species that often play keystone roles in ecosystems through direct (i.e., predation) and indirect (i.e., perceived predation risk) effects. Worldwide many carnivore species are experiencing rapid human-mediated population declines due to landscape change and habitat disturbance. For researchers, carnivores present unique challenges due to their large home ranges, low population densities, sensitivity to human disturbance, and direct persecution. Further, growing evidence shows that human activity can impact carnivore behavior and community structure by altering predator-prey interactions, shifting diel activity patterns, and altering wildlife movement leading to increased sightings, nuisance reports, and harvests. To investigate how …


Patterns Of Vertebrate Richness Across Global Anthromes: Prioritizing Conservation Beyond Biomes And Ecoregions, John E. Quinn, Emma K. Cook, Nicolas Gauthier Jun 2021

Patterns Of Vertebrate Richness Across Global Anthromes: Prioritizing Conservation Beyond Biomes And Ecoregions, John E. Quinn, Emma K. Cook, Nicolas Gauthier

Open Access Fund Publications

There is a clear need to refocus the way we prioritize conservation actions at a global scale to incorporate human systems. Anthromes have been suggested as one tool for integrating anthropogenic effects on ecosystems, but spatially explicit comparisons of biodiversity patterns are limited at a global extent. To address this gap, we used global data sets of anthromes and terrestrial vertebrate richness. We ranked anthromes by richness to all and threatened species at a global scale, temperate and tropical extents, and within major geographic regions. We tested for correlations between overall richness and count of threatened species, between taxonomic groups …


Larval Chondrocranial And Internal Oral Morphology Of The Neotropical Treefrog Boana Crepitans (Wied-Neuwied, 1824; Amphibia, Anura, Hylidae), Marianna Isabella Rosa Rodrigues De Oliveira, Luiz Norberto Weber, Johnny Sousa Ferreira, Anna Evelin Coimbra Liborio, André Masahide Guimaraes Takazone, Rafael O. De Sá May 2021

Larval Chondrocranial And Internal Oral Morphology Of The Neotropical Treefrog Boana Crepitans (Wied-Neuwied, 1824; Amphibia, Anura, Hylidae), Marianna Isabella Rosa Rodrigues De Oliveira, Luiz Norberto Weber, Johnny Sousa Ferreira, Anna Evelin Coimbra Liborio, André Masahide Guimaraes Takazone, Rafael O. De Sá

Biology Faculty Publications

We describe the internal oral morphology and chondrocranial anatomy for Boana crepitans tadpoles, and compare them with available descriptions for other species in the subfamily Cophomantinae. Among species of the Boana faber group, the chondrocranial anatomy has been reported only for one species internal oral morphology and cranial anatomy are similar to other described species of Boana and Cophomantinae. B. crepitans lacks unique features in the oral cavity and chondrocranium that would distinguish it from other congeneric species. We identify six characters from the internal oral anatomy of tadpoles unique for Cophomantinae. In addition, Boana has infralabial papillae projections, buccal …


Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker May 2021

Analysis Of Symptom Expressions And Transmission Rates Caused By The Plant Pathogen Phytophthora Ramorum On Native Chaparral Plants From The Genus Arctostaphylos, Bharati Gaonker

Natural Sciences and Mathematics | Biological Sciences Master's Theses

Phytophthora ramorum is the causal agent of Sudden Oak death (SOD), ramorum dieback and ramorum leaf blight which affect both forest environments and nurseries. This oomycete pathogen has had a huge economic impact on the nursery and lumber industry. Forests in California have experienced substantial mortality of oaks affecting the forest dynamics and diversity. Our research investigates four native species and two ornamental cultivars of plants, which belong to the genus Arctostaphylos (manzanita) and are considered to be new hosts for P. ramorum in the chaparral ecosystem of California. Symptom expression and transmission rates were analyzed on Arctostaphylos glauca, …


Phantom Rivers Filter Birds And Bats By Acoustic Niche, D. G. E. Gomes, C. A. Toth, H. J. Cole, C. D. Francis, J. R. Barber May 2021

Phantom Rivers Filter Birds And Bats By Acoustic Niche, D. G. E. Gomes, C. A. Toth, H. J. Cole, C. D. Francis, J. R. Barber

Biology Faculty Publications and Presentations

Natural sensory environments, despite strong potential for structuring systems, have been neglected in ecological theory. Here, we test the hypothesis that intense natural acoustic environments shape animal distributions and behavior by broadcasting whitewater river noise in montane riparian zones for two summers. Additionally, we use spectrally-altered river noise to explicitly test the effects of masking as a mechanism driving patterns. Using data from abundance and activity surveys across 60 locations, over two full breeding seasons, we find that both birds and bats avoid areas with high sound levels, while birds avoid frequencies that overlap with birdsong, and bats avoid higher …