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Animal Sciences

2017

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Articles 1 - 30 of 124

Full-Text Articles in Physical Sciences and Mathematics

Integrating Herbivore Population Dynamics Into A Global Land Biosphere Model: Plugging Animals Into The Earth System, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Wei Ren, Shufen Pan, Jia Yang, Nicola Di Cosmo, Amy Hessl Dec 2017

Integrating Herbivore Population Dynamics Into A Global Land Biosphere Model: Plugging Animals Into The Earth System, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Wei Ren, Shufen Pan, Jia Yang, Nicola Di Cosmo, Amy Hessl

Plant and Soil Sciences Faculty Publications

Mammalian herbivores are an essential component of grassland and savanna ecosystems, and with feedbacks to the climate system. To date, the response and feedbacks of mammalian herbivores to changes in both abiotic and biotic factors are poorly quantified and not adequately represented in the current global land surface modeling framework. In this study, we coupled herbivore population dynamics in a global land model (the Dynamic Land Ecosystem Model, DLEM 3.0) to simulate populations of horses, cattle, sheep, and goats, and their responses to changes in multiple environmental factors at the site level across different continents during 1980–2010. Simulated results show …


Of Rats And Men, Thomas S. Walsh Dec 2017

Of Rats And Men, Thomas S. Walsh

Capstones

This capstone is a data-driven investigation into New York City's rat problem. By using publicly available government data to map rat activity in NYC, I identified several socio-economic variables that correlate with rat populations at the community district, borough, and city-scale. I used these findings (mainly that rat problems are linked to lower incomes) as the basis of an investigation, which includes interviews with residents, experts, and city officials. Prof. Bobby Corrigan, urban rodentologist and formerly with the NYC Department of Health criticizes the city's efforts for the first time on the record.

https://thomasseiyawalsh.wixsite.com/ratstone


Translating Statistical Species-Habitat Models To Interactive Decision Support Tools, Lyndsie S. Wszola, Victoria L. Simonsen, Erica F. Stuber, Caitlyn R. Gillespie, Lindsey N. Messinger, Karie L. Decker, Jeffrey J. Lusk, Christopher F. Jorgensen, Andrew A. Bishop, Joseph J. Fontaine Dec 2017

Translating Statistical Species-Habitat Models To Interactive Decision Support Tools, Lyndsie S. Wszola, Victoria L. Simonsen, Erica F. Stuber, Caitlyn R. Gillespie, Lindsey N. Messinger, Karie L. Decker, Jeffrey J. Lusk, Christopher F. Jorgensen, Andrew A. Bishop, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Understanding species-habitat relationships is vital to successful conservation, but the tools used to communicate species-habitat relationships are often poorly suited to the information needs of conservation practitioners. Here we present a novel method for translating a statistical species-habitat model, a regression analysis relating ring-necked pheasant abundance to landcover, into an interactive online tool. The Pheasant Habitat Simulator combines the analytical power of the R programming environment with the user-friendly Shiny web interface to create an online platform in which wildlife professionals can explore the effects of variation in local landcover on relative pheasant habitat suitability within spatial scales relevant to …


Assessing Preservation Priorities Of Caves And Karst Areas Using The Frequency Of Endemic Cave-Dwelling Species, Eugen Nitzu, Marius Vlaicu, Andrei Giurginca, Ioana N. Meleg, Ionut Popa, Augustin Nae, Ştefan Baba Dec 2017

Assessing Preservation Priorities Of Caves And Karst Areas Using The Frequency Of Endemic Cave-Dwelling Species, Eugen Nitzu, Marius Vlaicu, Andrei Giurginca, Ioana N. Meleg, Ionut Popa, Augustin Nae, Ştefan Baba

International Journal of Speleology

Endemic and rare species as bioindicators of habitat vulnerability were used to develop protection and management plans for biotope prioritization (mainly islands habitats, lava tubes or groundwaters). Due to their narrow distribution, the endemic species (species confined to a restricted geographic area) are more susceptible to ecological disequilibrium and habitat loss than the widespread ones. Consequently, endemics become endangered in the context of ecological disturbance caused by anthropogenic pressure, making them suitable candidates to assess environmental preservation needs. Taking into consideration that most of the stygobitic and troglobitic species are endemic and confined to specific karst areas, based on their …


Forecasting The Spread And Invasive Potential Of Apple Snails (Pomacea Spp.) In Florida, Stephanie A. Reilly Dec 2017

Forecasting The Spread And Invasive Potential Of Apple Snails (Pomacea Spp.) In Florida, Stephanie A. Reilly

HCNSO Student Theses and Dissertations

Forecasting the potential range of invasive species is a critical component for risk assessment, monitoring, and management. However, many of these invasive species are not yet at equilibrium which can be problematic for many modelling approaches. Using the climate matching method, MaxEnt, a series of species distribution models (SDMs) and risk analysis maps were created for select apple snail species in Florida: Pomacea canaliculata, P. diffusa, and P. maculata. Apple snails, freshwater gastropods in the family Ampullariidae, are native to South America and were introduced to the United States via the pet trade approximately 40 years ago. …


A Comparative Life Cycle Assessment Of Nutritionally Equivalent Meals With And Without Pork, Kelli Young Dec 2017

A Comparative Life Cycle Assessment Of Nutritionally Equivalent Meals With And Without Pork, Kelli Young

Graduate Theses and Dissertations

The following report details a life cycle assessment of several dietary and meal scenarios with and without pork. The goal of the LCA was to identify the impacts of greenhouse gas emissions, water use, and land use of pork containing and porkless diets and meal plans in a field-to-fork analysis. The dietary and meal plan scenarios are iso-caloric meaning they contain the same number of calories. The first set of diets is based on a USDA consumption pattern, 2000 kcal per day. This diet was used to create three other dietary scenarios with and without pork. The USDA recommended food …


Evaluation Of Striped Bass Stocks In Virginia: Monitoring And Tagging Studies, 2015-2019 Progress Report 1 September 2016 - 31 November 2017, Philip W. Sadler, Lydia M. Goins, John M. Hoenig, Savannah Michaelsen, Maya L. Groner, Robert E. Harris Nov 2017

Evaluation Of Striped Bass Stocks In Virginia: Monitoring And Tagging Studies, 2015-2019 Progress Report 1 September 2016 - 31 November 2017, Philip W. Sadler, Lydia M. Goins, John M. Hoenig, Savannah Michaelsen, Maya L. Groner, Robert E. Harris

Reports

This report presents the results of striped bass (Morone saxatilis) tagging and monitoring activities in Virginia during the period 1 September 2016 through 31 August 2017. It includes an assessment of the biological characteristics of striped bass taken from the 2017 spring spawning run and estimates of annual survival and fishing mortality based on annual spring tagging. Also included is an investigation on the potential use of close-kin analyses to determine the size of the spawning stock in the Rappahannock River and an evaluation of mortality rates associated with the bacterial dermal disease mycobacteriosis in relation to water …


Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen Nov 2017

Evaluating The Ecological Status Of The Introduced Nile Monitor (Varanus Niloticus) In Florida: Forecasting Presence And Population Expansion Using Computational Geographic Information Systems, Noah G. Cohen

HCNSO Student Theses and Dissertations

The Nile monitor (Varanus niloticus) is a large, carnivorous lizard that has become a notorious invasive species in Florida, USA. Initially released in the 1980s from the pet trade, the species has since established at least three breeding populations and spread throughout much of southern Florida. While current control efforts have failed to eradicate V. niloticus, it is important to attain a better understanding of its invasive dynamics to guide and inform better control strategies. In this study, available georeferenced records of V. niloticus in Florida were compiled and linked to a habitat classification map to evaluate ecotype preferences. Factored …


A Study Of The Urban Red Fox (Vulpes Vulpes) Population In Baton Rouge, Louisiana Using Social Media, Ahsennur Soysal Nov 2017

A Study Of The Urban Red Fox (Vulpes Vulpes) Population In Baton Rouge, Louisiana Using Social Media, Ahsennur Soysal

LSU Master's Theses

Foxes are timid yet resourceful animals that are integrated into many urban environments. Because they are elusive, collecting information about the number of urban foxes, their diet and spatial distribution, their interactions with the ecological community in their urban habitat, as well as residents’ response to them, is difficult. Involving stakeholders to participate in the data collection on wildlife via citizen science on social media is one way to overcome this complication, while simultaneously engaging residents in the ecology happening around them. Therefore, we used social media as the platform to engage the public to document and map the foxes …


The Ecology Of Antibiotic Resistance: Sources And Persistence Of Vancomycin-Resistant Enterococci And Antibiotic Resistant Genes In Aquatic Environments, Suzanne M. Young Nov 2017

The Ecology Of Antibiotic Resistance: Sources And Persistence Of Vancomycin-Resistant Enterococci And Antibiotic Resistant Genes In Aquatic Environments, Suzanne M. Young

USF Tampa Graduate Theses and Dissertations

The growing crisis of antibiotic resistance is a major threat to ecosystems and human health. Infections caused by known and emerging antibiotic resistant pathogens are on the rise globally, with approximately 700,000 deaths per year caused by antibiotic resistant bacteria (1). In the United States, infections from antibiotic resistant bacteria cause more than 2 million illnesses and 23,000 deaths (2). Antibiotic resistant bacteria and antibiotic resistance genes are released into aquatic ecosystems through hospital waste, residential sewer lines and animal agricultural waste streams. Animal agriculture accounts for approximately 70% of antibiotic use in the United States (3). In agricultural ecosystems, …


Climate Change And Food Systems: Assessing Impacts And Opportunities, Meredith T. Niles, Richie Ahuja, Jimena M. Esquivel, Nelson Mango, Mil Duncan, Martin Heller, Cristina Tirado Nov 2017

Climate Change And Food Systems: Assessing Impacts And Opportunities, Meredith T. Niles, Richie Ahuja, Jimena M. Esquivel, Nelson Mango, Mil Duncan, Martin Heller, Cristina Tirado

College of Agriculture and Life Sciences Faculty Publications

No abstract provided.


A Brief Guide To Striped Bass Ecology & Management In Chesapeake Bay, Mary C. Fabrizio, Troy D. Tuckey, Susanna Musick Nov 2017

A Brief Guide To Striped Bass Ecology & Management In Chesapeake Bay, Mary C. Fabrizio, Troy D. Tuckey, Susanna Musick

Reports

Chesapeake Bay striped bass support important recreational fisheries along the US Atlantic coast; in the late 1970s, the population of striped bass collapsed as a result of overfishing and poor water quality in rivers used for spawning and rear-ing of young. Informed by stock assessments, strict management regulations were enacted in the mid-1980s and early 1990s; these highly effective regulations resulted in the recovery of the population in 1995. A key to the successful recov-ery of the Atlantic coast striped bass was the wide range of ages of spawning females and the associated differences in spawning behavior among ages. Age …


Modelling Bird Migration With Motus Data And Bayesian State-Space Models, Justin Baldwin Oct 2017

Modelling Bird Migration With Motus Data And Bayesian State-Space Models, Justin Baldwin

Masters Theses

Bird migration is a poorly-known yet important phenomenon, as understanding movement patterns of birds can inform conservation strategies and public health policy for animal-borne diseases. Recent advances in wildlife tracking technology, in particular the Motus system, have allowed researchers to track even small flying birds and insects with radio transmitters that weigh fractions of a gram. This system relies on a community-based distributed sensor network that detects tagged animals as they move through the detection nodes on journeys that range from small local movements to intercontinental migrations. The quantity of data generated by the Motus system is unprecedented, is on …


How Useful Is Gsv As An Environmental Observation Tool? An Analysis Of The Evidence So Far., Katherine Nesse, Leah Airt Oct 2017

How Useful Is Gsv As An Environmental Observation Tool? An Analysis Of The Evidence So Far., Katherine Nesse, Leah Airt

SPU Works

Researchers in many disciplines have turned to Google Street View to replace pedestrian- or carbased in-person observation of streetscapes. It is most prevalent within the research literature on the relationship between neighborhood environments and public health but has been used as diverse as disaster recovery, ecology and wildlife habitat, and urban design. Evaluations of the tool have found that the results of GSV-based observation are similar to the results from in-person observation although the similarity depends on the type of characteristic being observed. Larger, permanent and discrete features showed more consistency between the two methods and smaller, transient and judgmental …


Cnemidophorus Sexlineatus And The Impacts The Environment Has On Its Population At The Braidwood Dunes, Jeremiah Soto Oct 2017

Cnemidophorus Sexlineatus And The Impacts The Environment Has On Its Population At The Braidwood Dunes, Jeremiah Soto

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Land Cover Change Shows Little Effect On Migration Patterns Of Wood Storks And Great Egrets, Johanna Smith Oct 2017

Land Cover Change Shows Little Effect On Migration Patterns Of Wood Storks And Great Egrets, Johanna Smith

Annual Symposium on Biomathematics and Ecology Education and Research

No abstract provided.


Counting Crabs: Assessment Of Mangrove Crab Diversity And Density Among Three Sites In Ushongo, Tanzania, Clarasophia Gust Oct 2017

Counting Crabs: Assessment Of Mangrove Crab Diversity And Density Among Three Sites In Ushongo, Tanzania, Clarasophia Gust

Independent Study Project (ISP) Collection

This study assessed the density and diversity of crabs across three mangrove forest zones in Ushongo, Tanzania. The aim was to understand variance in the composition and distribution of mangrove crabs in relation to mangrove tree composition gradients in the area. Sites were measured using a 200m line transect and 40-plot method. Data was also collected from a sand beach habitat to compare to the diversity and distribution of mangrove habitats. Diversity was analyzed using Simpson’s Index of Diversity and an ANOVA test on the average number of species found per plot in each site. Density was analyzed using an …


A Study Of Reptile Community Diversity Related To Habitat Characteristics At Marojejy National Park, Julia Kowala Oct 2017

A Study Of Reptile Community Diversity Related To Habitat Characteristics At Marojejy National Park, Julia Kowala

Independent Study Project (ISP) Collection

Marojejy National Park is known for its diversity. Though it is home to the silky sifaka, it has extensive populations of herpetofauna. Seventy-seven species of reptiles have been documented in Marojejy National Park. This study aimed to evaluate the reptile community diversity and habitat characteristics in the park through systematic searches of ten-by-ten-meter plots, and inventory of species as they were found throughout the park. Systematic searches yielded the finding of 19 of the total 25 species identified. Some species that were found had not been previously seen at Marojejy before, most notably, Brookesia sp. “Nosy Hara”, Brookesia desperata, Furcifer …


Vetcompass Australia: A National Big Data Collection System For Veterinary Science, Paul Mcgreevy, Peter Thomson, Navneet K. Dhand, David Raubenheimer, Sophie Masters, Caroline S. Mansfield, Timothy Baldwin, Ricardo J. Soares Magalhaes, Jacquie Rand, Peter Hill, Anne Peaston, James Gilkerson, Martin Combs, Shane Raidal, Peter Irwin, Peter Irons, Richard Squires, David Brodbelt, Jeremy Hammond Sep 2017

Vetcompass Australia: A National Big Data Collection System For Veterinary Science, Paul Mcgreevy, Peter Thomson, Navneet K. Dhand, David Raubenheimer, Sophie Masters, Caroline S. Mansfield, Timothy Baldwin, Ricardo J. Soares Magalhaes, Jacquie Rand, Peter Hill, Anne Peaston, James Gilkerson, Martin Combs, Shane Raidal, Peter Irwin, Peter Irons, Richard Squires, David Brodbelt, Jeremy Hammond

Paul McGreevy, PhD

VetCompass Australia is veterinary medical records-based research coordinated with the global VetCompass endeavor to maximize its quality and effectiveness for Australian companion animals (cats, dogs, and horses). Bringing together all seven Australian veterinary schools, it is the first nationwide surveillance system collating clinical records on companion-animal diseases and treatments. VetCompass data service collects and aggregates real-time, clinical records for
researchers to interrogate, delivering sustainable and cost-effective access to data from hundreds of veterinary practitioners nationwide. Analysis of these clinical records will reveal geographical and temporal trends in the prevalence of inherited and acquired diseases, identify frequently prescribed treatments, revolutionize clinical …


Rehabilitation Of An Injured Golden Eagle (Aquila Chrysaetos): A Case Study, Fida Muhammad Khan, Fakhar-I- Abbas, Abu Ul Hassan Faiz Sep 2017

Rehabilitation Of An Injured Golden Eagle (Aquila Chrysaetos): A Case Study, Fida Muhammad Khan, Fakhar-I- Abbas, Abu Ul Hassan Faiz

Journal of Bioresource Management

Habitat destruction and anthropogenic activities cause wild birds to migrate towards urban areas in search of food and sometimes nesting in high-roof buildings, where they are caught by local people using different techniques and are further used for hunting or recreational purposes. An injured Golden Eagle (Aquila chrysaetos) was found entangled in bushes near the vicinity of Balkasar Research Complex, Chakwal, Pakistan. After complete physical examination, a wound on the right wing and closed leg fracture was diagnosed. The successful treatment was done by anti-parasitic and anti-bacterial drugs with careful monitoring. Splint was adjusted after aligning the fractured …


Sea Level Rise May Increase Extinction Risk Of A Saltmarsh Ontogenetic Habitat Specialist, David S. Johnson, Bethany L. Williams Aug 2017

Sea Level Rise May Increase Extinction Risk Of A Saltmarsh Ontogenetic Habitat Specialist, David S. Johnson, Bethany L. Williams

VIMS Articles

Specialist species are more vulnerable to environmental change than generalist species. For species with ontogenetic niche shifts, specialization may occur at a particular life stage making those stages more susceptible to environmental change. In the salt marshes in the northeast U.S., accelerated sea level rise is shifting vegetation patterns from flood-intolerant species such as Spartina patens to the flood-tolerant Spartina alterniflora. We tested the potential impact of this change on the coffee bean snail, Melampus bidentatus, a numerically dominant benthic invertebrate with an ontogenetic niche shift. From a survey of eight marshes throughout the northeast U.S., small snails …


Modelling Walleye Population And Its Cannibalism Effect, Quan Zhou Aug 2017

Modelling Walleye Population And Its Cannibalism Effect, Quan Zhou

Electronic Thesis and Dissertation Repository

Walleye is a very common recreational fish in Canada with a strong cannibalism tendency, such that walleyes with larger sizes will consume their smaller counterparts when food sources are limited or a surplus of adults is present. Cannibalism may be a factor promoting population oscillation. As fish reach a certain age or biological stage (i.e. biological maturity), the number of fish achieving that stage is known as fish recruitment. The objective of this thesis is to model the walleye population with its recruitment and cannibalism effect. A matrix population model has been introduced to characterize the walleye population into three …


Rethinking Urban Green Infrastructure As A Means To Promote Avian Conservation, Allen Lau Aug 2017

Rethinking Urban Green Infrastructure As A Means To Promote Avian Conservation, Allen Lau

Master's Projects and Capstones

There is an under-recognized potential for cities to use urban green infrastructure to contribute to avian biodiversity conservation. At the global scale, climate change and growing urbanization are primary global drivers leading to decline and homogenization in world bird populations. Birds are fundamental and intricate species in ecosystems, and even in urban areas, act as indicator and regulator species contributing to healthy ecosystem function. While many cities have recognized the economic and social benefits associated with green spaces, such as the vast benefits ecosystem services provide to the urban dweller, the use of green spaces to concurrently contribute to avian …


Spatial Models To Account For Variation In Observer Effort In Bird Atlases, Andrew M. Wilson, Daniel W. Brauning, Caitlin Carey, Robert S. Mulvihill Aug 2017

Spatial Models To Account For Variation In Observer Effort In Bird Atlases, Andrew M. Wilson, Daniel W. Brauning, Caitlin Carey, Robert S. Mulvihill

Environmental Studies Faculty Publications

To assess the importance of variation in observer effort between and within bird atlas projects and demonstrate the use of relatively simple conditional autoregressive (CAR) models for analyzing grid-based atlas data with varying effort. Pennsylvania and West Virginia, United States of America. We used varying proportions of randomly selected training data to assess whether variations in observer effort can be accounted for using CAR models and whether such models would still be useful for atlases with incomplete data. We then evaluated whether the application of these models influenced our assessment of distribution change between two atlas projects separated by twenty …


A Hemimysis Driven Novel Ecosystem At A Modified Boulder Breakwall, Eric John Geisthardt Aug 2017

A Hemimysis Driven Novel Ecosystem At A Modified Boulder Breakwall, Eric John Geisthardt

Theses and Dissertations

The US Army Corps of Engineers (USACE) is mandated to maintain and repair aging breakwall structures in all commercial ports on the Great Lakes. In May of 2014, the construction of Milwaukee Harbor USACE “green” breakwall (GBW) reconciliation created complex rocky aquatic habitat by depositing cobble-sized stone as a veneer over standard 6-10 ton boulders, thus creating “control” (boulder) and “treatment” (cobble) habitats. The breakwall is home to a prolific population of Hemimysis anomala, the introduced Ponto-Caspian mysid, which is significantly more abundant on cobble versus boulders (p<0.05, using a novel trap for Hemimysis). Fish and forage communities were sampled in 2015 and 2016 using a combination of experimental and micromesh gill nets, night scuba diving surveys, and a novel Hemimysis trap. This nearshore lithophilic mysid appears to provide a significant new seasonal food resource in the Milwaukee Harbor for pelagic prey fishes during inshore spawning migrations and upwelling events. Alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax) fed heavily on Hemimysis with some individuals consuming hundreds of mysids. Night scuba diving surveys and gill netting confirmed that rainbow smelt preferred to forage on the cobble section (p<0.05), and also consumed more Hemimysis there than they did at the control breakwall site (p<0.05). Hemimysis were also the primary food item consumed by nearshore game fishes such as YOY yellow perch (Perca flavescens), YOY largemouth bass (Micropterus salmoides), and juvenile rock bass (Ambloplites rupestris) caught at the breakwall. This study provides the first documented evidence that where abundant in the Laurentian Great Lakes, Hemimysis do have the ability to significantly impact local food webs and drive the feeding ecology of both pelagic transient and nearshore resident fishes.


Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver Aug 2017

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …


A Comparative Analysis Of Feed And Environmental Factors On Broiler Growth In The United States, Alexandra Gulli Aug 2017

A Comparative Analysis Of Feed And Environmental Factors On Broiler Growth In The United States, Alexandra Gulli

Graduate Theses and Dissertations

Broiler production in the United States has become an important industry within the last half century. As the demand for poultry continues to increase and the concern of climate change also increases, it will become an important part of the industry to become more sustainable. This study uses a feed optimization model, a broiler growth model, and a life cycle assessment (LCA) to determine how feed ingredients and the barn environment can affect the broiler’s growth and production emissions. A multi-criteria ration optimization model is used to produce feeds based on carbon footprint and cost. A growth model is used …


Selection Of Breeding Stock By U.S. Meat Goat Producers, Narayan Nyaupane, Jeffrey Gillespie, Kenneth Mcmillin, Robert Harrison, Isaac Stienei Aug 2017

Selection Of Breeding Stock By U.S. Meat Goat Producers, Narayan Nyaupane, Jeffrey Gillespie, Kenneth Mcmillin, Robert Harrison, Isaac Stienei

Community & Leadership Development Faculty Publications

Using nationwide survey data, we investigate U.S. meat goat producer preferences and willingness to pay for meat goat breeding stock attributes. Discrete choice experiments were employed, and mixed logit and latent class models were used for analysis. Results showed that producers preferred animals that were highly masculine/feminine, had good structure and soundness, and were of the Boer breed, whereas they preferred fewer animals that were older, of Kiko and Spanish breeds, and priced higher. Significant preference heterogeneity was found among the respondents. Larger-scale producers had greater preference for high masculinity/femininity, good structure and soundness, and Boer bucks.


A Comparison Of Five Statistical Methods For Predicting Stream Temperature Across Stream Networks, Maike F. Holthuijzen Aug 2017

A Comparison Of Five Statistical Methods For Predicting Stream Temperature Across Stream Networks, Maike F. Holthuijzen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The health of freshwater aquatic systems, particularly stream networks, is mainly influenced by water temperature, which controls biological processes and influences species distributions and aquatic biodiversity. Thermal regimes of rivers are likely to change in the future, due to climate change and other anthropogenic impacts, and our ability to predict stream temperatures will be critical in understanding distribution shifts of aquatic biota. Spatial statistical network models take into account spatial relationships but have drawbacks, including high computation times and data pre-processing requirements. Machine learning techniques and generalized additive models (GAM) are promising alternatives to the SSN model. Two machine learning …


Botswana’S Elephant-Back Safari Industry – Stress-Response In Working African Elephants And Analysis Of Their Post-Release Movements, Tanya Lama Jul 2017

Botswana’S Elephant-Back Safari Industry – Stress-Response In Working African Elephants And Analysis Of Their Post-Release Movements, Tanya Lama

Masters Theses

Understanding how African elephants (Loxodonta africana) respond to human interactions in ecotourism operations is critical to safeguarding animal and human welfare and sustaining wildlife ecotourism activities. We investigated the stress response of elephants to a variety of tourist activities over a 15-month period at Abu Camp in northern Botswana. We compared fecal glucocorticoid metabolite (FGM) concentrations across three elephant groups, including: eight elephants in an elephant-tourism operation (Abu herd), three elephants previously reintroduced back into the wild from the Abu herd, and wild elephants. There were no differences in FGM concentrations between the three groups of elephants. The highest observed …