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Ecology

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Articles 91 - 120 of 1177

Full-Text Articles in Life Sciences

Distribution And Ecology Of The Cedar Keys Mole Skink (Plestiodon Egregius Insularis), Kevin M. Enge, Louis A. Somma, Paul E. Moler, Travis M. Thomas, Matthew T. Fedler, John M. Matter, Dennis C. Haney Jan 2025

Distribution And Ecology Of The Cedar Keys Mole Skink (Plestiodon Egregius Insularis), Kevin M. Enge, Louis A. Somma, Paul E. Moler, Travis M. Thomas, Matthew T. Fedler, John M. Matter, Dennis C. Haney

Papers in Herpetology

We conducted surveys for the Cedar Keys Mole Skink, Plestiodon egregius insularis (Mount), during 1989– 1999 and 2015–2024, examined museum vouchers, and compiled personal observations from others to determine the status and distribution of this subspecies, which has the smallest geographic distribution of the five subspecies and is being considered for federal listing. We observed Cedar Keys Mole Skinks on Airstrip Island, Atsena Otie, Cedar Point, Deer Island, North Key, Scale Key, Seahorse Key, Snake Key, and possibly Dog Island. We have anecdotal reports of Mole Skinks on Way Key, which contains the most potential habitat and is the main …


Long-Term Ichthyoplankton Monitoring Of The Moon River (Savannah, Ga) With A Focus On Climate Change, Bradley Cayson Jan 2025

Long-Term Ichthyoplankton Monitoring Of The Moon River (Savannah, Ga) With A Focus On Climate Change, Bradley Cayson

College of Graduate Studies: Theses & Dissertations

The presence of healthy fish populations is a cornerstone of many important ecological mechanisms. These populations are supported by the recruitment of ichthyoplankton, or the egg and larval stages of fishes, as the primary determinant of population growth. Increases in average global water temperatures can alter the composition of fish communities and thus the offspring found in planktonic stages. I compared a large data set of ichthyoplankton surveys completed from 2009-2011 to a replicated six-month sampling period from May – November of 2024. Collection was conducted weekly to biweekly during night flood tides using a fixed suspension ichthyoplankton net (1mm …


Adaptive Evolution Shapes The Transmissibility Of West Nile Virus In New York State, Sean M. Bialosuknia Jan 2025

Adaptive Evolution Shapes The Transmissibility Of West Nile Virus In New York State, Sean M. Bialosuknia

Electronic Theses & Dissertations (2024 - present)

Arthropod-borne viruses (arboviruses), which are maintained in nature in complex transmission cycles involving hematophagic invertebrates and their vertebrate hosts, are the cause of a significant and expanding global health burden. Defining arbovirus-host interactions is necessary if we are to understand the adaptive and epidemiological potential of arboviruses. The results presented with West Nile virus (WNV Flaviviridae: Orthoflavivirus), are a compilation of such studies. WNV is the most prevalent arboviral pathogen in the U.S. and the most geographically distributed arbovirus in the world. Despite the evolutionary potential of these RNA viruses, WNV and other arboviruses have experienced only limited …


Chiropterophagy By The Siberian Weasel (Mustela Sibirica): The First Record In The Russian Far East, Valeriya E. Omelko, Mikhail P. Tiunov Dec 2024

Chiropterophagy By The Siberian Weasel (Mustela Sibirica): The First Record In The Russian Far East, Valeriya E. Omelko, Mikhail P. Tiunov

International Journal of Speleology

Chiropterophagy is a widespread phenomenon, but only one case of bat consumption by sable has been documented in the Russian Far East. This study presents the first recorded instance of chiropterophagy by the Siberian weasel (Mustela sibirica) in the southern Russian Far East, based on excrement collected from the Solyanik Cave in the southern Sikhote-Alin Mountains in 2007. The excrement included bones from three bat species (Murina hilgendorfi, Myotis bombinus, Plecotus ognevi) and one vole species (Myodes rutilus). Our findings suggest that the Siberian weasel visits caves during the cold season, although …


Avian Adaptation To Thermal Gradients, Justin Wheeler Baldwin Dec 2024

Avian Adaptation To Thermal Gradients, Justin Wheeler Baldwin

Arts & Sciences Graduate Student Theses and Dissertations

Life on Earth has adapted to extremely different temperatures worldwide. However, across distant branches of the tree of life, animals in similar temperature environments often share similar phenotypic traits. Specifically, traits that bear on the ratio between an individual’s surface area (e.g. appendage length) and its volume (e.g. body size) are particularly important for temperature regulation and are codified in canonical biogeographical rules. Although these global patterns of finding larger-bodied (Bergmann’s Rule) and shorter-limbed (Allen’s Rule) animals in colder regions are widely upheld, they also show substantial variation. It remains poorly understood why some animals conform to these biogeographical rules …


Climate And Gypsum Parent Material Shape Biocrust Communities And Moss Ecology In The Chihuahuan And Mojave Deserts, Nicole Pietrasiak, Katelyn G. Gobbie, Brian Jusko, Rebecca E. Drenovsky Dec 2024

Climate And Gypsum Parent Material Shape Biocrust Communities And Moss Ecology In The Chihuahuan And Mojave Deserts, Nicole Pietrasiak, Katelyn G. Gobbie, Brian Jusko, Rebecca E. Drenovsky

Life Sciences Faculty Research

Biological soil crust communities (biocrusts) establishing on gypsum soils have been well-documented for their prolific appearance and rich diversity of lichens and bryophytes. However, studies characterizing gypsum biocrusts have occurred primarily outside of the U.S., most of which lack comparisons to other soil types. We conducted intensive field surveys to evaluate the ground cover and frequency of biocrust functional groups and moss species on gypsum and non-gypsum soils in the U.S. regions with the most extensive gypsum outcrops, the northern Chihuahuan and eastern Mojave Deserts. Study sites were stratified by geomorphology and paired, so that every gypsum site was matched …


High-Severity Wildfires Alter Ant (Hymenoptera: Formicidae) Foraging Assemblage Structure In Montane Coniferous Forests And Grasslands In The Jemez Mountains, New Mexico, Usa, Jonathan Knudsen, Robert Parmenter, Theodore Sumnicht, Robin M. Verble Dec 2024

High-Severity Wildfires Alter Ant (Hymenoptera: Formicidae) Foraging Assemblage Structure In Montane Coniferous Forests And Grasslands In The Jemez Mountains, New Mexico, Usa, Jonathan Knudsen, Robert Parmenter, Theodore Sumnicht, Robin M. Verble

Biological Sciences Faculty Research & Creative Works

High-severity wildfires create heterogeneous patterns of vegetation across burned landscapes. While these spatial patterns are well-documented, less is known about the short- and long-term effects of large-scale high-severity wildfires on insect community assemblages and dynamics. Ants are bottom-up indicators of ecosystem health and function that are sensitive to disturbance and fill a variety of roles in their ecosystems, including altering soil chemistry, dispersing seeds, and serving as a key food resource for many species, including the federally endangered Jemez Mountain salamander (Plethodon neomexicanus). We examined the post-fire effects of the 2011 Las Conchas Wildfire on ant communities in the Valles …


The Effects Of Livestock On Mosquito Diversity And Abundance In Hidalgo County, Taylor Nicole Moya Dec 2024

The Effects Of Livestock On Mosquito Diversity And Abundance In Hidalgo County, Taylor Nicole Moya

Theses and Dissertations

Mosquitoes are detrimental to animals and threaten humans. More information is needed on how farm animal presence may impact mosquito abundance and diversity at farms. My goal in this study is to determine if there is any correlation between animal abundance or diversity on a farm and the abundance and diversity of mosquitoes collected. Hidalgo County, Texas, has a subtropical desert climate, ideal for mosquitoes. I hypothesized that the mosquito abundance and diversity indices would increase as the livestock abundance or diversity increases. Adult mosquitoes were collected using two CO2-baited light traps per farm from Spring 2022 to Fall 2022. …


An Overview Of Tsetse Fly Repellents: Identification And Applications, Olabimpe Y. Orubuloye, Njelembo J. Mbewe, David P. Tchouassi, Abdullahi A. Yusuf, Christian W.W. Pirk, Baldwyn Torto Nov 2024

An Overview Of Tsetse Fly Repellents: Identification And Applications, Olabimpe Y. Orubuloye, Njelembo J. Mbewe, David P. Tchouassi, Abdullahi A. Yusuf, Christian W.W. Pirk, Baldwyn Torto

All Peer-Reviewed Publications

Tsetse flies are vectors of the parasite trypanosoma that cause the neglected tropical diseases human and animal African trypanosomosis. Semiochemicals play important roles in the biology and ecology of tsetse flies. Previous reviews have focused on olfactory-based attractants of tsetse flies. Here, we present an overview of the identification of repellents and their development into control tools for tsetse flies. Both natural and synthetic repellents have been successfully tested in laboratory and field assays against specific tsetse fly species. Thus, these repellents presented as innovative mobile tools offer opportunities for their use in integrated disease management strategies.


Constancy In Pasture Composition?, D Scott Oct 2024

Constancy In Pasture Composition?, D Scott

IGC Proceedings (1977-2023)

Four lines of evidence are presented showing that, as for natural vegetations, there tends to be a linear relationship in developed grasslands between the logarithm of the proportion of different species in II sward and their rank order. These are: the Rothamsted Grass Park plots; the dry-weight-rank technique; published pasture composition data; and experimental mini-swards,


Integrating Multiple Biodiversity Metrics To Assess Diatom Diversity And Diatom/Macrophyte Host Specificity In Four Florida Benchmark Lakes, Alana Jade Bronk Oct 2024

Integrating Multiple Biodiversity Metrics To Assess Diatom Diversity And Diatom/Macrophyte Host Specificity In Four Florida Benchmark Lakes, Alana Jade Bronk

USF Tampa Graduate Theses and Dissertations

Biodiversity is declining across all natural environments, however, freshwater systems are thought to be among the most threatened. Quantifying and understanding trends in freshwater biodiversity has become more urgent as rapid biodiversity loss continues. To provide a robust ecological assessment, more than one bioindicator should be used, along with multiple biodiversity metrics. Macrophytes and diatoms are important components of aquatic systems, especially in shallow lakes. The relationship between macrophytes and epiphytic diatoms, though, is not clearly understood, and has not been well-studied, particularly in Florida, which has the largest abundance of natural freshwater lakes in the southeastern U.S This study …


Effects Of Roadways On Seasonal Movement Strategies And Mate Location Success In An Imperiled Pit Viper (Crotalus Horridus), Elizabeth J. Noble Oct 2024

Effects Of Roadways On Seasonal Movement Strategies And Mate Location Success In An Imperiled Pit Viper (Crotalus Horridus), Elizabeth J. Noble

Graduate Research Showcase

A detailed understanding of animal movement behavior is fundamental to effective conservation and management. Within populations, a diversity of movement strategies can be displayed in search of critical resources, and these strategies are influenced by multiple interacting factors related to individuals and the environment. Mating partners are one critical resource that often serves as a prominent selective force shaping movement during mating seasons. For many large-bodied snakes, such as pit vipers (Viperidae: Crotalinae), male mate- searching movements are the primary determinant of mate location success. During this time, males incur significant risks associated with elevated movement. In an increasingly human- …


The Ecology Of Grazing Management, R K. Heitschmidt Sep 2024

The Ecology Of Grazing Management, R K. Heitschmidt

IGC Proceedings (1977-2023)

The broad objective of this paper is to review the fundamental principles of grazing management as a means of assessing the inherent value of intensive and extensive grazing systems. Conceptual analyses of intensive and extensive grazing systems reveal that the fundamental differences between intensive and extensive grazing systems are related to differences in non-grazing rather than grazing tactics. Intensive grazing systems employ a wide array of non-grazing tactics in an attempt to overcome the inherent ecological constraints that limit secondary (i.e., livestock) productivity in extensively grazed systems. Moreover, analyses of the ecological or true efficiency of various agricultural production systems …


An Ecological Approach To Forage Management, J L. Brock, R.J M. Hay Sep 2024

An Ecological Approach To Forage Management, J L. Brock, R.J M. Hay

IGC Proceedings (1977-2023)

The principles of defoliation management for maximum production of quality herbage are well researched, namely the manipulation of frequency and severity of defoliation, but their impact on the various levels of ecological organisation in pastures is nol fully understood or their interpretation appreciated. Using grazed ryegrass-white clover pasture as; example, detailed sward studies have suggested the following model. Defoliation frequency and severity interact lo produce varying levels of physiological stress and morphological adaptation which affecl the survival rate and size of individual growth units, the lowest level of organisation. Increasing frequency of defoliation reduces organ size but increases survival rate …


Montane Molluscs: Factors Affecting Snails And Their Trematodes Throughout The Mountain Regions Of Arkansas, Taylor Michelle Fiedor Sep 2024

Montane Molluscs: Factors Affecting Snails And Their Trematodes Throughout The Mountain Regions Of Arkansas, Taylor Michelle Fiedor

Student Theses and Dissertations

Spatial processes across both broad and fine scales are important for understanding ecosystem function. Broad-scale spatial processes can be defined as elevational, latitudinal, or longitudinal processes whereas fine-scale spatial processes represent movement and dispersal among habitat patches. Historically, studies on freshwater snail distributions have focused on fine-scale processes with secondary consideration given to spatial sampling. Species inventories for freshwater snails are outdated because historically snail species descriptions were based on shell morphology, which is highly plastic. In Arkansas, it is estimated that there are 36 freshwater snail species, but this estimate does not account for shell plasticity and does not …


Of Geese And Grass: Investigating Impacts Of Brant Grazing On Eeelgrass, Dakota L. Osborne Sep 2024

Of Geese And Grass: Investigating Impacts Of Brant Grazing On Eeelgrass, Dakota L. Osborne

Master's Theses

Grazing pressure is important in structuring plant communities, particularly in aquatic environments. Eelgrass (Zostera marina), a keystone species in estuaries across North America, is experiencing widespread population declines. As a keystone species, eelgrass provides numerous important functions, including: 1) water filtration, 2) sediment stabilization, 3) providing refuge and nursery habitat for numerous species, and 4) carbon sequestration. Benefits which could be lost if eelgrass beds continue to diminish. California has experienced some of the greatest eelgrass declines, and Morro Bay, CA experienced a 96% decrease in eelgrass from 2007 to 2017. Most studies to date have examined bottom-up …


Chinese Tallow Long-Term Impact On Stand Dynamics In A Bottomland Hardwood Forest Following Vegetation Management, Nicklaus R. Langlois Aug 2024

Chinese Tallow Long-Term Impact On Stand Dynamics In A Bottomland Hardwood Forest Following Vegetation Management, Nicklaus R. Langlois

Electronic Theses and Dissertations

Chinese tallow (Triadica sebifera (L.) Small) is an invasive tree known to have negative impacts on bottomland hardwood forests. Chinese tallow is proficient in reproducing and surviving in bottomland hardwood forests because it is more flood and shade tolerant than most native trees. The long-term effectiveness of Chinese tallow control is an important topic to research as only a few long-term studies of Chinese tallow control have been conducted. A 10-year re-measurement of 22 paired plots installed in 2012 on the Pineywoods Mitigation Bank near Diboll, Texas following herbicide treatments examined Chinese tallow and native tree stand structure. Each …


Impact Of Site Rehabilitation On Local Insect And Pollinator Populations: A Case Study Of Newly Restored Mining Lands In Butte, Montana, Nicholas Rasschaert Aug 2024

Impact Of Site Rehabilitation On Local Insect And Pollinator Populations: A Case Study Of Newly Restored Mining Lands In Butte, Montana, Nicholas Rasschaert

Graduate Theses & Non-Theses

Pollinators play a critical role in ecosystem functionality, with 80% of the world's plant species depending on animal-mediated pollination. Given that habitat loss is a primary threat to pollinators and many species are becoming threatened in the US, restoration efforts must focus not only on plant communities but also on their pollinating animal counterparts. Including pollinator-focused strategies in rehabilitation plans is crucial, particularly in areas that have experienced significant environmental degradation, such as post-industrial and mining landscapes. This study assessed insect and plant diversity across eight sites within the Silver Bow Creek/Butte Area Superfund site, located in southwestern Montana. The …


Native Grasses: Their Distribution And Management In South-Eastern Australia, P M. Dowling, D L. Garden, P C. Simpson, D Eddy, D R. Kemp Aug 2024

Native Grasses: Their Distribution And Management In South-Eastern Australia, P M. Dowling, D L. Garden, P C. Simpson, D Eddy, D R. Kemp

IGC Proceedings (1977-2023)

The economic survival of landholders depends on improving net returns. On the Tablelands of New South Wales, where substantial tracts of the original native perennial grasses still remain, an opportunity to do this exists by making belier use of these pastures. Over 150 years of grazing by sheep and cattle is considered to have resulted in the evolution of more grazing tolerant and nutrient­responsive grasses. This paper reports on the approach taken in developing a native grass strategy for tableland country, A survey sought to delineate the distribution of the native grass species under grazed conditions, while the feasibility of …


Climatic Variation In The Monsoonal Subtropics Of China And Its Effect On Grassland Farming, Jizhou Ren, Xianglin Li, P.N P. Matthews Aug 2024

Climatic Variation In The Monsoonal Subtropics Of China And Its Effect On Grassland Farming, Jizhou Ren, Xianglin Li, P.N P. Matthews

IGC Proceedings (1977-2023)

The subtropical regions of China, making up 28% of the total area of the country, are characterised by 3 types of ecological environment as a result of effects of the monsoon climate: Indian Ocean monsoon­dominated (dry winter-spring), Pacific Ocean monsoon-dominated (hot, dry summer), and highland transitional (moderate) types. Bach of these has specific patterns of humidity (referred to as K value) and pasture growth. The main constraints to and opportunities for grasshind farming in China's subtropics are highlighted.


An Agro-Ecological Approach To Breeding Subterranean Clover (Trifolium Subterraneaum L.), P.G H. Nichols Aug 2024

An Agro-Ecological Approach To Breeding Subterranean Clover (Trifolium Subterraneaum L.), P.G H. Nichols

IGC Proceedings (1977-2023)

An ecologically based breeding method has recently been adopted by the National Subterranean Clover Improvement Programme in Australia. It differs from the traditional pedigree method by allowing F2-derived lines lo continue segregating in the F4 to F6 generations in target environments under regenerating, grazed sward conditions. Advantages of the new method include: (i) assessment of field performance in the early generations; (ii) Inclusion of regeneration processes in selection procedures; (iii) allowing effects of natural selection to act on segregating lines; and (iv) allowing regional testing centres lo become involved in early generation selection. Disadvantages include possible distortion in the direction …


Distribution And Abundance Of Plant Species In Pastures And Rangelands, John G. Mcivor Aug 2024

Distribution And Abundance Of Plant Species In Pastures And Rangelands, John G. Mcivor

IGC Proceedings (1977-2023)

The competition-stress-disturbance (CSD) model of Grime (Plant strategies and vegetation processes, New York, John Wiley 1979) is used as the basis for discussing the forces that influence the distribution and abundan.ce. of plant species. Characteristics of plant strategies (competitive, ruderal and stress-tolerator) in both the established and regenerative phases are summarised. Pasture management can be viewed as the manipulation of competition, stress and disturbance. A number of pasture situations ( disturbance-diversity relationships, pasture degradation, weed invasion, management of abandoned farm land, species conservation) are analysed in ecological terms and the consequences for pasture management are outlined. The CSD model can …


Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha Aug 2024

Unraveling The Behavioral Ecology Of The Western Diamond-Backed Rattlesnake (Crotalus Atrox) Through The Lenses Of Personality, Predator-Prey Interactions, And Crypsis, Oceane Da Cunha

Open Access Theses & Dissertations

To thrive in an environment, individuals need to be able to forage efficiently and acquire mates. These resources are limited, and their acquisition depends upon the energy and time an individual chooses to allocate to each activity and the environmental conditions, leading to behavioral trade-offs. Different species, or even different individuals within the same population, respond to these trade-offs by employing contrasting strategies, leading to differential life-history outcomes. The overarching goal of this dissertation is to gain a better understanding of the trade-offs cryptic ambush mesopredators are facing using the western diamond-backed rattlesnake (Crotalus atrox) as a model species. Each …


Unraveling Wetland Ecology: The Effect Of Abiotic Heterogeneity And Habitat Size On Wetland Plant Diversity In The Piedmont, Gregory T. Gilmore Aug 2024

Unraveling Wetland Ecology: The Effect Of Abiotic Heterogeneity And Habitat Size On Wetland Plant Diversity In The Piedmont, Gregory T. Gilmore

All Theses

Ecosystems around the world are seeing an unprecedented decline in biodiversity. However, to better prevent this decline we cannot only understand the drivers of biodiversity loss, but also the factors that support diversity. Traditional ecological hypotheses such as the Habitat Heterogeneity Hypothesis (HHH) and the Theory of Island Biogeography (TIB) have provided frameworks for understanding biodiversity drivers. However, recent research suggests a more nuanced relationship between heterogeneity, habitat size, and diversity than previously thought. This study looks to bridge existing research gaps by examining the ecologically and conservational important habitat of wetlands. Specifically, the study focuses on the plant diversity …


The Role Of Forest Disturbance And Habitat Characteristics In Shaping Arthropod Ecology., Kane Alec Lawhorn Aug 2024

The Role Of Forest Disturbance And Habitat Characteristics In Shaping Arthropod Ecology., Kane Alec Lawhorn

Electronic Theses and Dissertations

Disturbances in forests often generate dead wood, which is an important resource for a variety of arthropods. In tropical wet forests where fire is rare, lightning and branchfalls are common disturbances that create canopy gaps with associated large amounts of localized dead wood. By contrast, prescribed fire is a common disturbance in temperate forest that creates habitat heterogeneity and widely dispersed dead wood resources. The ecological effects of these disturbances on arthropod communities are largely unknown. This dissertation investigates how disturbance and habitat associations in both tropical and temperate forest shape arthropod ecology. Throughout, I primarily focus on beetles, ants, …


Antimicrobials Produced By Ants: Chemical Properties And Microbe Specificity, Katy Chon Jul 2024

Antimicrobials Produced By Ants: Chemical Properties And Microbe Specificity, Katy Chon

Master's Theses

Antibiotic resistance is a growing public health concern worldwide, and for over a decade, we have been witnessing the growth of difficult to treat infectious diseases caused by bacteria that are becoming resistant to antibiotics. This resistance can be mostly related to the misusing and improper use of antibiotics in both humans and animals. To restore this problem, humans have turned to new sources for the production of antibiotics. In this study, we focused on using ants. Social insects, including ants and bees, have faced strong disease pressures during their evolution and have developed a range of methods to fight …


Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan Jul 2024

Microplastic Accumulation In The Marsh Periwinkle (Littoraria Irrorata), Sarah Keaton, Hannah Lukhard, Eli Windy, Manar Hasan

DePaul Discoveries

Contamination of oceans by microplastics (mm) currently poses a major threat to aquatic and terrestrial ecosystems worldwide. Recent attention towards this issue has raised questions about the extent to which microplastics have accumulated in the environment, and has led to an increase in studies on the effects of microplastics in various organisms. However, levels of contamination in protected natural areas are still largely unexplored, yet can offer an important empirical perspective on the issue. In addition, little is known about the potential effects of microplastics on behavior in the field. This research was conducted within the protected ACE Basin National …


Feather Mites Through Genomic And Ecological Lenses: Host Specificity And Symbiosis At Multiple Levels Of Organization, Alix Elizabeth Matthews Jun 2024

Feather Mites Through Genomic And Ecological Lenses: Host Specificity And Symbiosis At Multiple Levels Of Organization, Alix Elizabeth Matthews

Student Theses and Dissertations

Symbionts, or organisms that form close and persistent associations with hosts, are ubiquitous across the tree of life, and symbioses are among the most common interspecific interactions in the natural world. Symbionts play a fundamental ecological and evolutionary role across multiple levels of biological organization – from individuals to ecosystems – and can have strong effects on global biodiversity. However, many aspects of these relationships are poorly understood including symbiont genetic diversity (inter- and intraspecific), host specificity, and the mechanisms underlying their functional nature or any context-dependent patterns. This dissertation uses a model symbiosis between permanent, obligate, ectosymbiotic vane-dwelling feather …


A Multispecies Hierarchical Model To Integrate Count And Distance-Sampling Data, Neil A. Gilbert, Caroline M. Blommel, Matthew T. Farr, David S. Green, Kay E. Holekamp, Elise F. Zipkin Jun 2024

A Multispecies Hierarchical Model To Integrate Count And Distance-Sampling Data, Neil A. Gilbert, Caroline M. Blommel, Matthew T. Farr, David S. Green, Kay E. Holekamp, Elise F. Zipkin

Institute for Natural Resources Publications

Integrated community models—an emerging framework in which multiple data sources for multiple species are analyzed simultaneously—offer opportunities to expand inferences beyond the single-species and single-data-source approaches common in ecology. We developed a novel integrated community model that combines distance sampling and single-visit count data; within the model, information is shared among data sources (via a joint likelihood) and species (via a random-effects structure) to estimate abundance patterns across a community. Parameters relating to abundance are shared between data sources, and the model can specify either shared or separate observation processes for each data source. Simulations demonstrated that the model provided …


From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel May 2024

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …