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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Theoretical investigation of the eco-evolutionary dynamics of food webs / 食物網の進化生態学的動態に対する理論的研究

Takahashi, Daisuke 23 July 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18497号 / 理博第4012号 / 新制||理||1578(附属図書館) / 31383 / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 山内 淳, 教授 工藤 洋, 教授 田村 実 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
12

Estimating Clapper Rail (Rallus Crepitans) Survivorship and Implementation of Estimates into Individual-Based Population Models

Feura, Jared 14 December 2018 (has links)
Sea-level rise is a concern for the future of coastal marsh obligate species such as the Clapper Rail (Rallus crepitans). Clapper Rails possess the potential to indicate changes to marsh ecological state due to population variation related to habitat features exhibited in previous study. Estimates for Clapper Rail survival are among the key missing parameters to create predictive models for Clapper Rail populations. I estimated Clapper Rail survival using data collected from six automated telemetry towers located in two Mississippi marshes. Thirty adult rails were harnessed with radio transmitters around telemetry towers to provide evidence of a rail’s status, alive or dead. Using survival estimates in conjunction with existing empirical data, I created an individual-based model that incorporated existing Sea-level Affecting Marsh Models, which predict changing land cover. These models showed that Clapper Rails will likely persist, though at decreased populations, through changes in habitat due to sea-level rise.
13

Individual-based modeling of microbial systems under consideration of consumer-resource interactions and evolution

Bogdanowski, André 22 July 2022 (has links)
Ecological systems are difficult to understand, let alone predict. The reason is their enormous complexity that arises from numerous organisms interacting with each other and their environment in a multitude of ways. However, this understanding is crucial to secure a plentitude of services that are provided by ecological systems. A substantial proportion of these services are carried out by microorganisms such as bacteria, fungi, and archaea. For example, microorganisms contribute to degradation of organic matter, water purification, and even regulation of the global climate. Therefore, a thorough understanding of the ecology of microorganisms is particularly relevant for our future well-being. While microorganisms are comparatively well-suited for experimental studies, owing also to recent technological advances in molecular biology, it is necessary to apply theory and modeling in order to fully benefit from the empirical data. A widely used theoretical method in microbial ecology is individual-based modeling, in which population or community dynamics emerge from the behavior and interplay of individual entities that are simulated according to a predefined set of rules. However, existing individual-based models of microbial communities are often specialized on particular research questions or require proficiency in specific programming languages or software. These limitations can be hampering for a broad and systematic application of individual-based modeling in microbial ecology. For this thesis, McComedy, a framework and software tool for the creation and running of individual-based models of microbial consumer-resource systems, was developed. It allows for fast and user-friendly model development by flexibly combining pre-implemented building blocks that represent physical, biological, and evolutionary processes. The ability of McComedy to capture the essential dynamics of microbial consumer-resource systems was demonstrated by reproducing and furthermore adding to the results of two distinct studies from the literature. McComedy was furthermore applied to study the evolution of metabolic interactions between bacteria. More specifically, it was assessed whether cooperative exchange of costly metabolites can evolve in bacterial multicellular aggregates. The results indicate that this is in principle possible, however, it depends on the mechanism by which the metabolites are exchanged. If metabolites are exchanged via diffusion through extracellular space, cooperation is not expected to evolve. On the other hand, if metabolites are transferred by contact-dependent means, for instance via intercellular nanotubes, cooperation is likely to evolve. Overall, contributions from this thesis comprise, first, a user-friendly modeling tool that can be used by microbial ecologists, second, insights into the evolution of metabolic interactions in bacterial systems, and, third, awareness of how the mechanistic consideration of a process can drastically affect the outcome of a modeling study.
14

The Forgotten Segment : Older Consumers’ Reaction to Online Individual-Based Marketing

Karlsson, Maja, Kovacevic, Irma January 2024 (has links)
Social media marketing is more prevalent than ever before, and Individual-based Marketing online, Cookies and various advertisements are becoming a part of daily life for many. At the same time the elderly population is ever increasing. The elderly are also one of the most misrepresented groups in our current society, it is an extremely generalised group, where market research is not often prevalent. This study therefore aims to increase understanding of how elderly view and interact with online Individual-based Marketing on Facebook, and what implications the answer to this question may bring for the future of marketing. The aim is answered by using literature reviews of past research, various theories, as well as a qualitative study. The qualitative study consists of semi structured interviews with stimuli. Ten Swedish pensioners were interviewed, and this resulted in a large variety of answers. The results conveyed that elderly are not homogenous in their view and use of social media, as well as most Individual-based Marketing, in this case on Facebook, were not well fitted to their interests, resulting in a need to improve segmentation in various ways.  Some of the elderly also had a difficult time understanding and trusting technology, such as clicking on advertisements, what they viewed to be trustworthy and what not. However, others seemed to have no issues regarding online behaviour as well as marketing, which further proves that pensioners are not a homogeneous group and that this needs to be understood to improve targeted marketing and segmentation.  Further research suggestions within the topic are to study different income classes, as well as a larger variety of elderly, from various communities. It could also be interesting to study elderly’s source criticism and how that affects their Cookies acceptance and further Individual-based Marketing.
15

Efeito do distúrbio nas estratégias de vida : dinâmicas evolutivas e ecológicas / Disturbance effect on life strategies: evolutionary and ecological dynamics

Gonçalves, Luísa Novara Monclar 24 August 2017 (has links)
A ocorrência de distúrbios impacta a diversidade de estratégias de vida em comunidades e a evolução de estratégias de vida em populações. Na Ecologia, o distúrbio é estudado enquanto fator ambiental que altera a disponibilidade de recursos e a abundância das populações, ocasionando a exclusão competitiva de espécies menos favorecidas a depender da intensidade e da frequência de sua ocorrência. Na Biologia Evolutiva, o distúrbio é avaliado enquanto pressão que, dependendo de sua regularidade no ambiente, determina a intensidade da resposta evolutiva das espécies e, assim, a adaptação a estratégias de vida de maior aptidão. Ainda que haja separação entre as duas áreas, a dinâmica ecológica influencia a dinâmica evolutiva e vice-versa. Estudos que integram Ecologia e Evolução têm sido cada vez mais recorrentes, no entanto, poucos ou nenhum consideram o distúrbio. Neste trabalho, utilizamos um modelo baseado em indivíduo para criar cenários nos quais os processos de adaptação e exclusão competitiva de espécies possam ocorrer, tanto conjunta quanto isoladamente, a fim de entender como o distúrbio determina as estratégias de vida presentes em comunidades sob dinâmicas ecológicas, evolutivas e eco-evolutivas. No modelo, as estratégias de vida são atributos herdáveis definidos por um trade-off entre longevidade e fecundidade. O cenário evolutivo foi composto por populações (apenas uma espécie) com mutação; o cenário ecológico, por diversas espécies sem mutação e o cenário eco-evolutivo, por diversas espécies com mutação. Observamos que o distúrbio esteve positivamente relacionado com a predominância de indivíduos fecundos em todos os cenários, mas o efeito do distúrbio sobre a diversidade de estratégias variou. Nos cenários evolutivo e eco-evolutivo, a diversidade de estratégias aumentou com a intensificação do distúrbio, enquanto no cenário ecológico a diversidade caiu. Isso indica a importância da mutação como fonte de novas variantes da estratégia quando há alta renovação de indivíduos da comunidade, condicionada pela mortalidade elevada. Apenas no cenário eco-evolutivo houve um pico de heterogeneidade de estratégias em níveis intermediários de distúrbio. Neste cenário, o isolamento reprodutivo das espécies, em contraposição à pan-mixia que ocorre dentro das populações, permite que as espécies difiram em relação à sua estratégia de vida média. Em paralelo, a entrada constante de variantes de estratégias por mutação previne a extinção definitiva das estratégias do sistema. Assim, quando o nível de distúrbio é intermediário, tanto espécies mais fecundas quanto espécies mais longevas conseguem coexistir na comunidade. Dado que os diferentes cenários resultaram em padrões distintos de frequência relativa de estratégias de vida, este trabalho evidencia a importância de estudarmos o efeito do distúrbio na estrutura e na dinâmica de comunidades unindo processos que são tipicamente estudados de forma isolada pela Ecologia e pela Biologia Evolutiva / Disturbance events impact life strategy diversity in communities and life strategy evolution in populations. In the field of Ecology, disturbance occurrence is studied while an environmental factor that alters resource availability and populations abundance, causing competitive exclusion of less favorable life strategies depending on disturbance frequency and intensity. In the field of Evolutionary Biology, disturbance is evaluated as a pressure, depending on its spatial and temporal regularity, that determines the intensity of species\' evolutionary response and, as a consequence, the adaptation towards the fittest life strategy. Although there is a separation between these two fields of knowledge, ecological dynamics influence evolutionary dynamics and the other way around. Studies that mix Ecology and Evolution are becoming more common, but few or none of them takes disturbance in consideration. Here, we use an individual-based model to generate contexts in which adaptation and competitive exclusion might act apart and together in order to understand how disturbance determines life strategies that occur in communities under ecological, evolutionary and eco-evolutionary dynamics. In the model, life strategy is an inheritable character defined for a trade-off between longevity and fecundity. Simulations from the evolutionary context were composed by one population under mutation acting, simulations from the ecological context by various species without mutation and simulations from the eco-evolutionary context by various species with mutation occurrence. We observed that disturbance was positively correlated with fecund individuals preponderance in all contexts but that disturbance effect on life strategy diversity varied between the different contexts. In the evolutionary and the eco-evolutionary contexts, life strategy diversity increased with disturbance raise, while in the ecological context diversity decreased. This result evidences the mutation role as a source of new life strategy variants when there is a high renovation of individuals given by raised mortality. Only in the eco-evolutionary context there was an interspecific heterogeneity peak on intermediate levels of disturbance. In this scenario, species reproductive isolation, in contrast to populations panmixy, allows species to differ in relation to its life strategies. In parallel to this, the constant input of new life strategy variants by mutation prevents the definite extinction of life strategies from the system. Therefore, when disturbance level is intermediate, productive species as well as long-lived ones are able to coexist. Given that the different contexts resulted in varied patterns of life strategies\' relative frequency, this study evidences the importance of studying disturbance effect on communities structure and dynamics unifying processes that are typically separated between Ecology and Evolution fields
16

Efeito do distúrbio nas estratégias de vida : dinâmicas evolutivas e ecológicas / Disturbance effect on life strategies: evolutionary and ecological dynamics

Luísa Novara Monclar Gonçalves 24 August 2017 (has links)
A ocorrência de distúrbios impacta a diversidade de estratégias de vida em comunidades e a evolução de estratégias de vida em populações. Na Ecologia, o distúrbio é estudado enquanto fator ambiental que altera a disponibilidade de recursos e a abundância das populações, ocasionando a exclusão competitiva de espécies menos favorecidas a depender da intensidade e da frequência de sua ocorrência. Na Biologia Evolutiva, o distúrbio é avaliado enquanto pressão que, dependendo de sua regularidade no ambiente, determina a intensidade da resposta evolutiva das espécies e, assim, a adaptação a estratégias de vida de maior aptidão. Ainda que haja separação entre as duas áreas, a dinâmica ecológica influencia a dinâmica evolutiva e vice-versa. Estudos que integram Ecologia e Evolução têm sido cada vez mais recorrentes, no entanto, poucos ou nenhum consideram o distúrbio. Neste trabalho, utilizamos um modelo baseado em indivíduo para criar cenários nos quais os processos de adaptação e exclusão competitiva de espécies possam ocorrer, tanto conjunta quanto isoladamente, a fim de entender como o distúrbio determina as estratégias de vida presentes em comunidades sob dinâmicas ecológicas, evolutivas e eco-evolutivas. No modelo, as estratégias de vida são atributos herdáveis definidos por um trade-off entre longevidade e fecundidade. O cenário evolutivo foi composto por populações (apenas uma espécie) com mutação; o cenário ecológico, por diversas espécies sem mutação e o cenário eco-evolutivo, por diversas espécies com mutação. Observamos que o distúrbio esteve positivamente relacionado com a predominância de indivíduos fecundos em todos os cenários, mas o efeito do distúrbio sobre a diversidade de estratégias variou. Nos cenários evolutivo e eco-evolutivo, a diversidade de estratégias aumentou com a intensificação do distúrbio, enquanto no cenário ecológico a diversidade caiu. Isso indica a importância da mutação como fonte de novas variantes da estratégia quando há alta renovação de indivíduos da comunidade, condicionada pela mortalidade elevada. Apenas no cenário eco-evolutivo houve um pico de heterogeneidade de estratégias em níveis intermediários de distúrbio. Neste cenário, o isolamento reprodutivo das espécies, em contraposição à pan-mixia que ocorre dentro das populações, permite que as espécies difiram em relação à sua estratégia de vida média. Em paralelo, a entrada constante de variantes de estratégias por mutação previne a extinção definitiva das estratégias do sistema. Assim, quando o nível de distúrbio é intermediário, tanto espécies mais fecundas quanto espécies mais longevas conseguem coexistir na comunidade. Dado que os diferentes cenários resultaram em padrões distintos de frequência relativa de estratégias de vida, este trabalho evidencia a importância de estudarmos o efeito do distúrbio na estrutura e na dinâmica de comunidades unindo processos que são tipicamente estudados de forma isolada pela Ecologia e pela Biologia Evolutiva / Disturbance events impact life strategy diversity in communities and life strategy evolution in populations. In the field of Ecology, disturbance occurrence is studied while an environmental factor that alters resource availability and populations abundance, causing competitive exclusion of less favorable life strategies depending on disturbance frequency and intensity. In the field of Evolutionary Biology, disturbance is evaluated as a pressure, depending on its spatial and temporal regularity, that determines the intensity of species\' evolutionary response and, as a consequence, the adaptation towards the fittest life strategy. Although there is a separation between these two fields of knowledge, ecological dynamics influence evolutionary dynamics and the other way around. Studies that mix Ecology and Evolution are becoming more common, but few or none of them takes disturbance in consideration. Here, we use an individual-based model to generate contexts in which adaptation and competitive exclusion might act apart and together in order to understand how disturbance determines life strategies that occur in communities under ecological, evolutionary and eco-evolutionary dynamics. In the model, life strategy is an inheritable character defined for a trade-off between longevity and fecundity. Simulations from the evolutionary context were composed by one population under mutation acting, simulations from the ecological context by various species without mutation and simulations from the eco-evolutionary context by various species with mutation occurrence. We observed that disturbance was positively correlated with fecund individuals preponderance in all contexts but that disturbance effect on life strategy diversity varied between the different contexts. In the evolutionary and the eco-evolutionary contexts, life strategy diversity increased with disturbance raise, while in the ecological context diversity decreased. This result evidences the mutation role as a source of new life strategy variants when there is a high renovation of individuals given by raised mortality. Only in the eco-evolutionary context there was an interspecific heterogeneity peak on intermediate levels of disturbance. In this scenario, species reproductive isolation, in contrast to populations panmixy, allows species to differ in relation to its life strategies. In parallel to this, the constant input of new life strategy variants by mutation prevents the definite extinction of life strategies from the system. Therefore, when disturbance level is intermediate, productive species as well as long-lived ones are able to coexist. Given that the different contexts resulted in varied patterns of life strategies\' relative frequency, this study evidences the importance of studying disturbance effect on communities structure and dynamics unifying processes that are typically separated between Ecology and Evolution fields
17

An individual-based model of tsetse fly populations dynamics : modelling an extensive mark-release-recapture experiment

Ferreira, Roux-Cil 04 1900 (has links)
Thesis (MComm)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Tsetse flies (Glossina spp), native to mid-continental Africa, are the vectors of trypanosomes that causes human (sleeping sickness) and animal (nagana) trypanosomiasis. Vector control plays a major role in alleviating the burden of the disease. Mathematical models of tsetse population dynamics provide insights into how best to manage these control efforts. A major mark-recapture experiment, carried out in Zimbabwe, provided valuable information on tsetse population dynamics, but the analyses so far published could be improved on because not all of the information available on the marking procedure was used. We have constructed an individual-based model that follows the life of individual tsetse flies, their progeny and, in particular, the sequence of occasions on which individual flies were captured and given distinctive marks. We have access to comprehensive data from the tsetse fly mark-release-recapture experiment carried out on Antelope Island, Lake Kariba, Zimbabwe. In order to calibrate or validate the model, we model both the growth of the introduced tsetse population and the mark-recapture process. We have compared the model outputs to the original data and recommend processes that may be followed for model calibration. It is possible to construct an individual-based model that adequately models tsetse fly populations. Whereas the focus of this study has been on modelling the mark-recapture study, the individual-based model could also be used in more general settings to model the growth, and reduction in fly numbers, changes in age structure, species and gender ratios and the acquisition of trypanosome infections by individual flies. This model can thus be used to investigate the effect of various factors on tsetse fly and trypanosome, population dynamics as well as on the performance of various control techniques effecting fly mortality and disease transmission. / AFRIKAANSE OPSOMMING: Tsetsevlieë (Glossina spp), inheems aan sentraalkontinentale Afrika, is die draers van trypanosomen wat trypanosomiasis by die mens (slaapsiekte) en by diere (nagana) veroorsaak. Die beheer van draers speel 'n belangrike rol om die las wat die siekte veroorsaak, te verlig. Wiskundige modelle van tsetse bevolkingsdinamika bied insigte oor hoe om beheerpogings die beste te bestuur. 'n Belangrike merk-hervang eksperiment, wat in Zimbabwe uitgevoer is, bevat waardevolle inligting oor tsetse bevolkingsdinamika. Die ontleding daarvan, wat tot dusver gepubliseer is, kan egter verbeter word aangesien nie al die inligting beskikbaar in die merkprosedure, gebruik is nie. Ons het 'n individu-gebaseerde model saamgestel wat die lewens van individuele tsetsevlieë en hul nageslagte volg, in besonder die volgorde waarop individuele vlieë gevang en herkenbaar gemerk is. Ons het toegang tot omvattende data van die tsetsevlieg merk-vrylaat-hervang eksperiment wat uitgevoer is op Antelope Eiland, Karibadam, Zimbabwe. Ten einde die model te kalibreer of om die model se geldigheid te bevestig, modelleer ons beide die groei van die ingevoerde tsetse bevolking en die merk-hervangs metode. Ons vergelyk die modeluitsette met die oorspronklike data en beveel prosesse aan wat gevolg kan word om die model te kalibreer. Dit is moontlik om 'n individu-gebaseerde model saam te stel wat tsetsevliegbevolkings voldoende moduleer. Terwyl hierdie studie die modellering van die merk-hervang data bestudeer, kan die individueel-gebaseerde model ook gebruik word in meer algemene gevalle vir die modellering van die vermeerdering en vermindering in vlieë getalle, veranderinge in die ouderdomstruktuur, spesies en geslagverhoudings en die verwerwing van trypanosomen infeksies deur individuele vlieë. Hierdie model kan dus gebruik word om die effek te ondesoek van verskeie faktore op die tsetsevlieg en trypanosomen, populasiedinamiek sowel as die prestasie van verskillende beheertegnieke rakende vliegsterftes en siekte-oordrag.
18

Modèles individu-centrés de systèmes sociaux : micro-modèles hybrides inspirés des données simulant le développement rural ; dynamiques collectives de filtrage et / ou de rejet des messages / Individual based models of social systems : data driven hybrid micro-models of rural development and collective dynamics of filtering or rejecting messages

Huet, Sylvie 15 January 2013 (has links)
Cette thèse a pour objet la modélisation individu-centrée des systèmes sociaux. Une première partie orientée aide à la décision présente un modèle d’évolution des populations rurales fortement inspiré des données. Une seconde partie, plus théorique, étudie divers mécanismes permettant à un individu d’accepter ou de résister à une influence sociale. Nous proposons tout d’abord un modèle individu-centré de la dynamique des municipalités rurales européennes, implémenté pour le département du Cantal. Nous proposons un nouvel algorithme de génération des populations initiales ne nécessitant pas d’échantillon de population (approche classique). Nous concevons et paramétrons un modèle de la dynamique de l’individu face au marché du travail basé sur les données de la « European Labour Force Survey ». Il inclut des heuristiques originales de transition d’états tel qu’actifs, inactifs, chômeurs, … prenant en compte l’âge, la profession et le secteur d’activité de l’individu. Nous déterminons les dynamiques non fondés sur des données individuelles en testant la capacité de dynamiques simples à produire des résultats proches des données agrégées disponibles. Est ainsi conçu un modèle de mobilité résidentielle, expliquant partiellement la migration et intégrant décision de déménager et choix d’une nouvelle résidence. La seconde partie de la thèse étudie les effets collectifs de différents mécanismes permettant aux individus de résister à ou d’accepter une influence sociale. Un premier mécanisme étudié est un filtre cognitif impliquant qu’un individu ne reçoit pas une information incongruente ou peu importante. Les individus « filtreurs » exhibent le biais de primauté car leur attitude n’est déterminée que par les premiers éléments reçus et se montrent négatifs alors que le message diffusé par un media est neutre. Le taux d’individus négatifs dans la population est accru ou diminuer par l’échange direct d’information entre les individus. Un second mécanisme est un rejet de la tentative d’influence qui mène l’individu à différencier davantage son attitude de celle de son interlocuteur. Il intervient lorsque l’individu éprouve un inconfort lié au fait qu’il est à la fois en accord et en désaccord avec son interlocuteur. Le couplage de ce rejet à un mécanisme d’attraction entre individus en accord entraîne un nombre moindre de groupes d’opinion différentes à l’échelle de la population (ie par rapport au nombre de groupes obtenus avec le seul mécanisme d’attraction). / This thesis is dedicated to individual-based modeling of social systems. While the first part is very practical, decision-support oriented, presenting a model which studies the evolution of a rural population, the second part is more theoretical, interested in various mechanisms allowing individual to accept or resist to social influence. Firstly, we propose an individual-based model of the European rural municipalities implemented for the French Cantal département. We use a new sample-free algorithm for generating the initial population, while classical methods require an initial sample. We design and parameterize the individual activity dynamics with data from the European Labour Force Survey database. The individual dynamics includes an original heuristic for labour statuses and employments changes, based on individual age, profession and activity sector when she is occupied. The last part of the model deals with dynamics that we have not been able to derive from data, mainly the demographic dynamics. Based on the Occam razor principle, we test very simple dynamics and choose them on their capacity to lead to model results close to reference data. In particular, we propose a simple residential mobility model, partly ruling the emigration, which integrates decision to move and location choice. Secondly, we study the collective effects of various mechanisms leading individuals to resist or accept social influence. A first mechanism leads individuals to neglect some features of an object if they are not important enough or incongruent. These individuals exhibit the primacy bias because their attitudes are determined by the first accepted feature. We show that this bias increases when individuals directly exchange about features compared to when they only get the features from the media, in a random order. The second mechanism is a rejection reaction that we suppose occurring because of the discomfort taking place when individuals are close on one dimension of attitude and far on another dimension. The main effect of this rejection mechanism is to lead to a lower number of clusters than with the attraction mechanism alone.
19

Long-term effects of habitat and management changes on steelhead production: results from an individual-based model

Bolduc, Melanie B 04 May 2006 (has links)
Steelhead populations support an economically valuable fishery in the Great Lakes region. Development of the region, resulting in land use changes and the introduction of hydropower, has affected the riverine habitat used by steelhead. I have developed an individual-based model of steelhead in the Manistee River, Michigan that simulates the long-term production of steelhead from the river. The model begins each year with a spawning population that produces redds for that year and then follows the offspring from each redd as individuals until they smolt one, two, or three years after spawning. Simulations run for ten-year periods. The simulated individuals are subjected to mortality from predation, starvation, and temperature extremes. Predation is a length-based mortality and is thereby affected by growth. Growth is determined by an individual's foraging success and bioenergetics. I conducted simulation experiments to examine the effect of changes in spawning numbers, temperature, and flow regime, on the number of individuals smolting in the river each year. Simulations reveal that the current flow regime and colder water temperatures are most beneficial for steelhead production and increasing the number of spawners does not increase steelhead production. The results also suggest that the young-of-the-year (YOY) stages have the greatest impact on steelhead production because the model showed no indication that steelhead life stages older than the YOY could compensate for density-related losses that occurred during the first year.
20

Modeling Habitat Use and Road Based Disturbance of Mule Deer in New Mexico

Daniel E. Bird (5930552) 17 January 2019 (has links)
<p>As human activity expands across the globe, disturbance of wildlife by anthropogenic activities such as fragmentation of habitat, and wildlife-human conflicts escalate. The Pueblo of Santa Ana is receiving pressure from road expansion and urban development and is concerned with the impacts of those activities upon wildlife populations. Specifically, mule deer is a species of concern for their Department of Natural Resources (DNR). Mule deer are important economically, culturally, and for recreational purposes. The DNR understands the need for better understanding mule deer ecology to manage for potential conflicts in their interactions with expanding human infrastructure. My objectives were first to model mule deer habitat use in and around the Pueblo of Santa Ana during the summer and winter at different times of the day. My second objective was to understand the relative impacts of different scenarios for road development in the Pueblo of Santa Ana upon the disturbance of mule deer using an Individual Based Modeling (IBM) framework.</p> <p> Using Geospatial Positioning System telemetry collar data collected on mule deer I used proximity based habitat predictors in a general linear mixed model to create resource selection functions. Generally I found that the season had a greater impact on mule deer habitat use than the time of day. Female and male mule deer select for similar habitat but sexually segregate in their summer distributions. My findings are consistent with results from other locations where mule deer studies have been conducted. In chapter two, I used the Simulation of Disturbance Activities (SODA) modeling framework to investigate the impact of vehicles on mule deer disturbance response behaviors, alert and fleeing. Using this framework I compared a baseline scenario to road expansion scenarios (DamRoad, ByPass, DeerCrossing) estimating the frequency of disturbance behavior of mule deer for each such scenario. My results show that mule deer were disturbed most in the baseline model. There were no significant differences in the frequency of disturbance for female mule deer across scenarios. Male mule deer did have some significant differences in alert and fleeing behavior across scenarios. My results may be a function of assumptions made in my modeling. Specifically, I assumed that mule deer would shift their areas of activity to new portions of the Pueblo of Santa Ana in response to altered habitat quality caused by new roads. If mule deer did not shift their areas of activity accordingly, my models may provide inaccurate assessments of disturbance patterns. </p> In conclusion my findings are similar to results from other locations. Specifically, the inferences that roads and road development are important to consider for mule deer management transcends variation associated with the unique characteristics of the Pueblo of Santa Ana mule deer population. Finally, my results suggest that the use of an IBM modeling framework has the potential to provide insights into the disturbance of mule deer by vehicular traffic even if my conclusions were constrained by study design.

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