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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.
1

Binational collaboration in recovery of endangered species: the Mexican wolf as a case study

Bernal Stoopen, Jose Francisco 30 September 2004 (has links)
The goal of this inductive study was to identify factors that facilitate and inhibit binational collaboration in the recovery of endangered species in the northern Mexico borderlands, focusing on the Mexican wolf (Canis lupus baileyi). A conceptual model was developed using qualitative techniques, providing the basis for design of a mail survey. The target population included participants with experience in recovery efforts for over a dozen species at risk in the region. Long interviews were recorded with 44 participants from Mexico and the United States. Thematic hierarchical analysis was used to develop a conceptual model of how interviewees talked about factors influencing binational collaboration. Issues were classified in five thematic clusters: project, organization, people, resources, culture/history. The survey was used to conduct a needs assessment, measuring respondents' attitudes about the relative priority of issues identified in the conceptual model. High priority needs were identified from each thematic cluster: (a) equitable participation in project design and implementation, (b) continuity of personnel, (c) coordination of federal, state and local efforts, (d) increased funding, managed with accountability, and (e) exchange visits to facilitate understanding of diverse perspectives. Responses to almost half the survey items indicated accord among the sample of respondents, providing a basis for shared common ground. The nature of discord was within the range of "manageable", with no clear polarization of attitudes measured. This exploratory data analysis suggested that the structure of the conceptual model developed from the Mexican wolf case study was generally a valid basis for future deductive analysis and reflection by practitioners. For 82% of 22 statements of need, priorities of participants in the Mexican wolf recovery efforts did not differ significantly from other respondents. Nationality (of respondents) significantly affected priority rankings for only 18% of the need statements. Significant effects of five demographic variables indicated that interactive effects should be examined in future multivariate analyses to determine how respondents' attitudes on issues related to priority rankings. Recommendations were provided for a more efficient and effective approach to collaborative problem-solving, engaging reflective practitioners from the private and public sectors in principled negotiation processes to better understand diverse perspectives.
2

Population genetics, foraging ecology, and trophic relationships of grey wolves in central Saskatchewan

Urton, Erin Jaime Moira 20 December 2004
<p>Habitat fragmentation and anthropogenic development influence the level of isolation and security in and around protected habitats affecting wolf movements and the distribution and abundance of their prey. In light of recent concern about the ecology of animals in protected areas, I initiated a research project to investigate the molecular and foraging ecology of grey wolves in and around Prince Albert National Park (PANP), Saskatchewan. <p>Estimates of genetic diversity and population structure can be used as surrogates to detect effects of habitat degradation on wolves. Genetic diversity was high in these populations relative to other North American wolf populations. My results suggest that wolves in central Saskatchewan form a panmictic population, however there is some evidence showing partial isolation of one group of wolves within PANP. I speculate that the level of human activity such as road networks, hunting, and trapping act as dispersal impediments to this isolated group. Further, the genetic homogenization, indicating high population turnover, of wolf groups that use the periphery and adjacent areas of PANP may also contribute to the observed genetic subdivision. The partially isolated NW group, characterized by slightly lower diversity indices, low migration rates, and higher levels of allele fixation, indicated this group was a more stable social unit comprised of more related individuals.</p><p>Knowledge of wolf food habits and how they change over time is a fundamental component to understanding wolf ecology. Using scat analysis I evaluated wolf foraging ecology by calculating indices of occurrence/faeces (OF) and percent prey biomass contribution: white tailed deer contributed 43% and 33% respectively to wolf diet; elk (33%, 50%), moose (7%, 14%), beaver (5%, 2%), and snowshoe hare (2%, <1%). I found no evidence of livestock depredation nor did wolves prey on bison or caribou. There were no differences in OF indices between years. Prey selectivity was apparent in both years with wolves selecting elk and avoiding beaver. A diversity of ungulate prey are readily available to wolves in this system; however, scat analysis and tests for prey selection indicate a preference for elk. I presume this is a choice made to balance risk with profitability of food items in concordance with optimal foraging theory.</p><p>I examined trophic relationships between the grey wolf and 18 mammalian species from the boreal forest of central Saskatchewan, Canada, using ä13C and ä15N stable isotope values measured in hair samples. Variance in isotope values for wolves and other carnivores was investigated as a proxy for dietary variation. IsoSource, an isotopic source partitioning model, quantified the relative proportions of 5 most likely prey items in the diets of wolves.</p><p>I compared these results with investigations of faecal contents using percent biomass contributions of prey items in wolf diet. I found no difference between percent biomass measures and mean percent contributions derived from IsoSource. Despite social foraging, my results indicate highly variable diets among individual wolves and I discuss this in terms of boreal wolf ecology.
3

Population genetics, foraging ecology, and trophic relationships of grey wolves in central Saskatchewan

Urton, Erin Jaime Moira 20 December 2004 (has links)
<p>Habitat fragmentation and anthropogenic development influence the level of isolation and security in and around protected habitats affecting wolf movements and the distribution and abundance of their prey. In light of recent concern about the ecology of animals in protected areas, I initiated a research project to investigate the molecular and foraging ecology of grey wolves in and around Prince Albert National Park (PANP), Saskatchewan. <p>Estimates of genetic diversity and population structure can be used as surrogates to detect effects of habitat degradation on wolves. Genetic diversity was high in these populations relative to other North American wolf populations. My results suggest that wolves in central Saskatchewan form a panmictic population, however there is some evidence showing partial isolation of one group of wolves within PANP. I speculate that the level of human activity such as road networks, hunting, and trapping act as dispersal impediments to this isolated group. Further, the genetic homogenization, indicating high population turnover, of wolf groups that use the periphery and adjacent areas of PANP may also contribute to the observed genetic subdivision. The partially isolated NW group, characterized by slightly lower diversity indices, low migration rates, and higher levels of allele fixation, indicated this group was a more stable social unit comprised of more related individuals.</p><p>Knowledge of wolf food habits and how they change over time is a fundamental component to understanding wolf ecology. Using scat analysis I evaluated wolf foraging ecology by calculating indices of occurrence/faeces (OF) and percent prey biomass contribution: white tailed deer contributed 43% and 33% respectively to wolf diet; elk (33%, 50%), moose (7%, 14%), beaver (5%, 2%), and snowshoe hare (2%, <1%). I found no evidence of livestock depredation nor did wolves prey on bison or caribou. There were no differences in OF indices between years. Prey selectivity was apparent in both years with wolves selecting elk and avoiding beaver. A diversity of ungulate prey are readily available to wolves in this system; however, scat analysis and tests for prey selection indicate a preference for elk. I presume this is a choice made to balance risk with profitability of food items in concordance with optimal foraging theory.</p><p>I examined trophic relationships between the grey wolf and 18 mammalian species from the boreal forest of central Saskatchewan, Canada, using ä13C and ä15N stable isotope values measured in hair samples. Variance in isotope values for wolves and other carnivores was investigated as a proxy for dietary variation. IsoSource, an isotopic source partitioning model, quantified the relative proportions of 5 most likely prey items in the diets of wolves.</p><p>I compared these results with investigations of faecal contents using percent biomass contributions of prey items in wolf diet. I found no difference between percent biomass measures and mean percent contributions derived from IsoSource. Despite social foraging, my results indicate highly variable diets among individual wolves and I discuss this in terms of boreal wolf ecology.
4

Binational collaboration in recovery of endangered species: the Mexican wolf as a case study

Bernal Stoopen, Jose Francisco 30 September 2004 (has links)
The goal of this inductive study was to identify factors that facilitate and inhibit binational collaboration in the recovery of endangered species in the northern Mexico borderlands, focusing on the Mexican wolf (Canis lupus baileyi). A conceptual model was developed using qualitative techniques, providing the basis for design of a mail survey. The target population included participants with experience in recovery efforts for over a dozen species at risk in the region. Long interviews were recorded with 44 participants from Mexico and the United States. Thematic hierarchical analysis was used to develop a conceptual model of how interviewees talked about factors influencing binational collaboration. Issues were classified in five thematic clusters: project, organization, people, resources, culture/history. The survey was used to conduct a needs assessment, measuring respondents' attitudes about the relative priority of issues identified in the conceptual model. High priority needs were identified from each thematic cluster: (a) equitable participation in project design and implementation, (b) continuity of personnel, (c) coordination of federal, state and local efforts, (d) increased funding, managed with accountability, and (e) exchange visits to facilitate understanding of diverse perspectives. Responses to almost half the survey items indicated accord among the sample of respondents, providing a basis for shared common ground. The nature of discord was within the range of "manageable", with no clear polarization of attitudes measured. This exploratory data analysis suggested that the structure of the conceptual model developed from the Mexican wolf case study was generally a valid basis for future deductive analysis and reflection by practitioners. For 82% of 22 statements of need, priorities of participants in the Mexican wolf recovery efforts did not differ significantly from other respondents. Nationality (of respondents) significantly affected priority rankings for only 18% of the need statements. Significant effects of five demographic variables indicated that interactive effects should be examined in future multivariate analyses to determine how respondents' attitudes on issues related to priority rankings. Recommendations were provided for a more efficient and effective approach to collaborative problem-solving, engaging reflective practitioners from the private and public sectors in principled negotiation processes to better understand diverse perspectives.
5

Scent-marking : investigating chemosensory signals in wolf urine

Wolfram, Wendi K. January 2013 (has links)
Identifying the best control method for problematic wildlife is an ever present issue in wildlife management. Popular control methods have ranged from lethal techniques, extirpating the animal, to multiple non-lethal methods focused on deterring undesired behavior. In the past, lethal methods were the preferred choice. However, with increased awareness of the need for biodiversity conservation, new management methods focus on non-lethal control, with emphasis on exploiting aspects of naturally occurring organismal behaviors and ecology. Over the past decade, technological advances in extraction method’s and equipment have also developed new techniques providing a broader range of information about species biology for management use. One of the most well documented conflicts between wildlife and humans is that of the wolf. Using advanced technology and new techniques, we investigated the implication of using chemosensory signals in canid urine to modify behavior as a possible non-lethal alternative in large predator management. Here we used the SBSE method coupled with improved GC/MS equipment to analyze the volatile organic compounds in the urine of four canid species, gray wolf (Canis lupus), red wolf (Canis rufus), wolf-dog hybrids (Canis familiaris) and the domestic dog (Canis familiaris) in order to create working urinary profiles. The extraction method identified several compounds also seen in the urinary profiles of other large predators. In addition, similarities and differences were also noted between taxa and the sexes, and these can be further explored in future studies. Two identified urinary compounds, acetophenone and methyl propyl sulfide, were selected for further behavioral evaluation. We focused on these compounds and their influence as chemosensory signals triggering urine marking events in both the gray wolf and red wolf. Behavioral observations of the effects of these two chemicals indicated they elicited responses from captive wolves. At each of the three study sites, the combination of these chemicals produced urine-marking events along the territory boundary by dominant animals. As a result, the investigation focused on what triggered the urine-marking events, the chemicals themselves, their combination, or the breakdown of the chemicals producing other odorants. It was found that there was no significant degradation of the chemicals over time and environmental conditions produced no significant breakdown of the acetophenone prior to the addition of methyl propyl sulfide. This posed a number of new questions and illustrated the need for additional behavioral studies. The results of this study analyzing chemosensory signals in canid urine, provides biologists with new information to aid in the development of new non-lethal management strategies for handling problematic wildlife as well as providing useful information for future research involving reproduction, predator/prey dynamics, territory maintenance, and a host of other studies focusing on animal ecology in association with chemosensory signaling.
6

Estimativa da população de cães errantes e a sua associação com fatores socieconômicos e ambientais / Estimation of stray dog\'s population and its association with socioeconomics and environmental factors

Guilloux, Aline Gil Alves 03 November 2011 (has links)
A população de cães errantes tem sido um problema na sociedade moderna e levanta discussão sobre o bem estar dos animais, a responsabilidade ambiental e assuntos relacionados saúde pública, como agressão, zoonoses e acidentes de trânsito. São Paulo é uma cidade com mais de dez milhões de habitantes e uma população de cães domiciliados em torno de 2,5 milhões de animais. Não há pesquisas a respeito da distribuição da população de cães errantes e isso dificulta o planejamento de ações de intervenção neste campo. O problema foi abordado do ponto de vista da probabilidade de abandono e capacidade de suporte ambiental. Foi criado um escore composto por treze variáveis de risco de abandono. Os dados foram agrupados por distrito administrativo e estes classificados em três categorias (tercis). Foi definida uma amostra de conveniência de seis áreas a serem visitadas, duas em cada categoria, que fossem pequenas e isoladas, passiveis de percorrer a pé. O número de animais foi estimado pelo método de pseudo-captura, utilizando fotos e anotações para identificar os animais. Simultaneamente, foi aplicado um questionário em uma amostra aleatória sistemática dos domicílios de cada área. Das seis áreas visitadas, em duas foi observada presença de cães errantes e em apenas uma delas, uma população fixa. Dos fatores associados a presença de cães errantes, destacam-se os relacionados a proximidade homem-cão e ao ambiente. Intervenções nestes fatores e incentivo à guarda responsável podem ser soluções desejáveis para redução gradativa da população de cães errantes / The stray dog\'s population of has been a problem in modern society and raises discussion on different issues like animal welfare, environmental responsibility and public health matters such as dogs bites, zoonosis and traffic accidents. Sao Paulo is a city with over ten million inhabitants and a population of owned dogs around 2.5 million animals. There are no surveys on the distribution of the population of stray dogs and this hampers any plan of intervention. The problem was accessed from the standpoint of relinquishment probability and environmental carrying capacity. A score was created with thirteen variables, of known risk factors of relinquishment. The data was grouped by district and classified in to three categories (terciles). a convenience sample of six areas was defined, two in each category, which were small and isolated, liable to go through on foot. The number of animals was estimated by the pseudo capture method, using photos and notes to identify the animals. Simultaneously, a questionnaire was administered in a systematic random sample of households in each area. Of the six areas visited, in only two it the presence of stray dogs was observed and only one showing a fixed stray population. Of the factors associated to the presence of stray dogs, one can distinguish: degree of human-dog proximity and those related to environment. Intervention on these factors and encouraging responsible ownership could be a solution to gradually reduce the population of stray dogs.
7

Estimativa da população de cães errantes e a sua associação com fatores socieconômicos e ambientais / Estimation of stray dog\'s population and its association with socioeconomics and environmental factors

Aline Gil Alves Guilloux 03 November 2011 (has links)
A população de cães errantes tem sido um problema na sociedade moderna e levanta discussão sobre o bem estar dos animais, a responsabilidade ambiental e assuntos relacionados saúde pública, como agressão, zoonoses e acidentes de trânsito. São Paulo é uma cidade com mais de dez milhões de habitantes e uma população de cães domiciliados em torno de 2,5 milhões de animais. Não há pesquisas a respeito da distribuição da população de cães errantes e isso dificulta o planejamento de ações de intervenção neste campo. O problema foi abordado do ponto de vista da probabilidade de abandono e capacidade de suporte ambiental. Foi criado um escore composto por treze variáveis de risco de abandono. Os dados foram agrupados por distrito administrativo e estes classificados em três categorias (tercis). Foi definida uma amostra de conveniência de seis áreas a serem visitadas, duas em cada categoria, que fossem pequenas e isoladas, passiveis de percorrer a pé. O número de animais foi estimado pelo método de pseudo-captura, utilizando fotos e anotações para identificar os animais. Simultaneamente, foi aplicado um questionário em uma amostra aleatória sistemática dos domicílios de cada área. Das seis áreas visitadas, em duas foi observada presença de cães errantes e em apenas uma delas, uma população fixa. Dos fatores associados a presença de cães errantes, destacam-se os relacionados a proximidade homem-cão e ao ambiente. Intervenções nestes fatores e incentivo à guarda responsável podem ser soluções desejáveis para redução gradativa da população de cães errantes / The stray dog\'s population of has been a problem in modern society and raises discussion on different issues like animal welfare, environmental responsibility and public health matters such as dogs bites, zoonosis and traffic accidents. Sao Paulo is a city with over ten million inhabitants and a population of owned dogs around 2.5 million animals. There are no surveys on the distribution of the population of stray dogs and this hampers any plan of intervention. The problem was accessed from the standpoint of relinquishment probability and environmental carrying capacity. A score was created with thirteen variables, of known risk factors of relinquishment. The data was grouped by district and classified in to three categories (terciles). a convenience sample of six areas was defined, two in each category, which were small and isolated, liable to go through on foot. The number of animals was estimated by the pseudo capture method, using photos and notes to identify the animals. Simultaneously, a questionnaire was administered in a systematic random sample of households in each area. Of the six areas visited, in only two it the presence of stray dogs was observed and only one showing a fixed stray population. Of the factors associated to the presence of stray dogs, one can distinguish: degree of human-dog proximity and those related to environment. Intervention on these factors and encouraging responsible ownership could be a solution to gradually reduce the population of stray dogs.
8

Vargen och vetenskapen : En fallstudie om vetenskapens roll inom vargförvaltningens beslutsfattning

Grönros, Amanda, Holmström Petterson, Sofia January 2017 (has links)
Sweden has through its membership of the EU, an obligation to strive that the wolf population should be both long and short time viability. The signed Convention on Biological Diversity means that the wolf population must meet a favorable conservation status, which has required a great need for scientific facts about what a sustainable status is. The relationship between science and decision making can be difficult, especially in complex environmental problems with many uncertainties. The purpose of this study is to examine the various scientific uncertainties and find out how they influence decision-making within the Swedish wolf policy. The focus is on the impact of the scientific advice for decision-makers. The study is a case study in which the results are based on five interviews with experts in the field as well as a deeper text analysis of the reports and regulations used in the decision-making process. In conclusion, the study indicates that research and scientific findings have had a major role in the decision-makers in wolf management. To some extent, it has also complicated the issue because of the lack of consensus among researchers. The attitude around Sweden's wolves extends far back in time and the conflict today is a contentious question that seems to act much about values ​​and not just scientific contradictions. / Sverige har genom sitt medlemskap i EU en skyldighet att sträva efter att vargens population ska vara både kortsiktigt och långsiktigt livskraftig. Den undertecknade konventionen om biologisk mångfald medför att vargstammen måste uppfylla en gynnsam bevarandestatus, vilket har krävt ett stort behov av vetenskapliga fakta kring vad en hållbar status är. Sambandet mellan vetenskap och beslutsfattande kan vara svår, särskilt i komplicerade miljöproblem med många osäkerhetsfaktorer. Syftet med studien är att granska de olika vetenskapliga osäkerheterna och ta reda på hur de påverkar beslutsprocessen inom svensk vargpolitik. Fokus ligger på den inverkan de vetenskapliga råden har för beslutsfattarna. Studien är en fallstudie där resultatet bygger på fem intervjuer med experter inom området, samt en djupare textanalys av de rapporter och förordningar som använts i beslutsprocessen. Sammanfattningsvis tyder studiens resultat på att forskning och vetenskapliga resultat har haft en stor roll för beslutsfattarna inom vargförvaltningen. Till viss del har den också försvårat frågan på grund av avsaknaden av konsensus bland forskarna. Attityden kring Sveriges vargar sträcker sig långt bak i tiden och konflikten är idag en laddad fråga som inte bara handlar om vetenskapliga motsättningar, utan även om värderingar.
9

Dynamique et conservation des populations difficilement observables : cas d'étude de la recolonisation du loup dans les Alpes françaises / Population dynamics and conservation of elusive species : recolonization of the French Alps by the wolf

Marescot, Lucile 03 December 2012 (has links)
En Europe, la présence de grands carnivores dans des paysages anthropisés entraîne une forte compétition avec l'homme et alimente d'importantes polémiques concernant leur protection légale. La perception antagoniste de ces espèces à la fois emblématiques pour certains et sources de conflits pour d'autres, rend la gestion de leurs populations très délicate. Depuis la recolonisation spontanée du loup (Canis lupus) dans les Alpes françaises au début des années 1990, la population s'est accrue numériquement et spatialement. Parallèlement, les dégâts occasionnés par le loup sur la filière élevage ont suivi la même tendance. L'Etat met en place aujourd'hui un contrôle raisonné de la population, sous réserve que les objectifs de conservation, exigés par la Directive Habitat, soient respectés. En s'inspirant du cas d'étude du loup en France, nous proposons dans cette thèse un cadre de prise de décision structurée adapté pour la gestion et la conservation d'espèces rares et difficilement observables, protégées par des accords législatifs mais qui, dans un contexte social conflictuel, peuvent être régulées. La modélisation séquentielle du processus décisionnel s'est déroulée dans un contexte de forte incertitude selon plusieurs étapes : 1) appréhender les objectifs de conservation et/ou contrôle du loup en France pour les formaliser sous forme mathématique via une fonction d'utilité, 2) suivre la population par une méthode non-invasive pour définir des indicateurs de gestion fiables et évaluer le statut de conservation de la population, 3) coupler les mesures létales adoptées actuellement à un modèle démographique décrivant la dynamique du loup et intégrant sa structure sociale, 4) et déterminer la décision. Cette dernière étape est réalisée à l'aide d'une méthode d'optimisation qui calcule la stratégie optimale de gestion en fonction de la structure sociale de la population et des différentes sources d'incertitude accumulées à chaque étape du processus décisionnel. Nous avons choisi comme indicateur de gestion le taux de croissance, à partir duquel nous avons défini l'utilité. Cet indicateur était robuste à l'incertitude d'échantillonnage émergeant de la détection partielle et hétérogène des individus. Des analyses de sensibilité de la décision ont montré une forte influence de la fonction d'utilité sur la stratégie optimale, soulignant ainsi l'importance de définir correctement les objectifs. Nous avons également montré que la stratégie optimale était sensible aux variations des paramètres démographiques, montrant ainsi l'intérêt des méthodes de capture-marquage-recapture pour les estimer correctement. Nous discutons enfin de l'extension de notre approche à un cadre décisionnel de gestion adaptative pour traiter des problèmes de conservation dans un contexte conflictuel. / Large carnivore management in Europe is controversial because of conflictive objectives arising from the legal protection of threatened species vs. the possible necessity of culling individuals to prevent severe damages on human activities. Since the wolf recovery in the French Alps in the early 90's, the population has been numerically and spatially increasing. In parallel, livestock depredations have been following the same trend. As an EU member state, France is bound to the European Habitat Directive, which provides full protection of wolf populations and their habitat. Nevertheless, derogatory killings are allowed for individuals causing problems on livestock and some lethal control is now incorporated into the national management plan, as long as the population growth and its distribution range are not being threatened. Illustrating with the case study of the wolf in France, my dissertation proposes a structured decision making framework for the management and the conservation of elusive species that are legally protected but, in a conflictive context, are subject to population control. The sequential modeling of our decision process occurred in the following steps: 1) define the multiple objectives and formulate them in terms of a utility function, 2) monitor the population through a non-invasive approach in order to define the population conservation status, 3) build a demographic model to predict the consequences of harvesting on population dynamics and social structure, 4) obtain optimal state-dependent decisions. The last step is done with stochastic dynamic programming (SDP), acknowledged to be one of the most useful optimization methods in decision making. We provide an optimal solution for wolf management that gives the highest chance of meeting objectives, defined on population growth rate. This demographic indicator was found to be robust to sampling uncertainty arising from partial and heterogeneous detection of individuals. We ran decision sensibility analyses and found a strong effect of the utility function on the optimal strategy, highlighting the importance of defining explicit objectives. We also found that the optimal strategy was sensitive to demographic parameters, which demonstrate the general need of using solid statistical approaches to estimate them properly. This structured decision making framework can further be extended to adaptive management, acknowledged as being a convenient framework for wildlife management.
10

Atributos individuais, formas de manejo e contexto ambiental: quais fatores determinam a chance de cachorros visitarem remanescentes florestais? / Individual traits, management and environmental context: which factors determine the chance of dogs visiting forest remnants?

Biffi, Vinícius Leonardo 17 August 2017 (has links)
Invasões biológicas representam hoje a segunda maior ameaça à biodiversidade, e o homem desempenha papel fundamental na introdução de espécies exóticas potencialmente invasoras. O cachorro (Canis lupus familiaris) é uma dessas espécies. Presente em todos os continentes, é o carnívoro mais abundante do mundo, e pode causar impactos à fauna nativa através de efeitos letais e não letais da predação, competição, hibridização e transmissão de doenças, além de ser potencialmente importante na epidemiologia de zoonoses. Em áreas rurais, que concentram grande parte dos remanescentes de vegetação nativa no mundo, os cachorros são frequentemente criados soltos e circulam livremente, intensificando a chance de contato com a fauna nativa. Nesse trabalho, avaliamos a importância relativa de fatores associados a atributos individuais (sexo, idade, condição de saúde, comportamento exploratório, tamanho e raça), formas de manejo (incentivo do dono à movimentação, motivo para a criação, confinamento e frequência de alimentação) e contexto ambiental (proximidade à mata nativa) para determinar a chance de cachorros visitarem remanescentes florestais em paisagens fragmentadas de Mata Atlântica. Selecionamos oito paisagens de 2830 ha cada, nas quais visitamos todas as construções em áreas rurais a fim de entrevistar, através da aplicação de questionário, os responsáveis pela criação de cachorros e fotografar os cachorros. Utilizamos a imputação múltipla para estimar os dados faltantes (comuns em dados obtidos via questionários), gerando 10 conjuntos de dados imputados que foram analisados separadamente. Por meio de seleções de modelos através do Critério de Informação de Akaike, comparamos modelos candidatos com até cinco variáveis independentes para determinar a chance de cachorros visitarem remanescentes florestais. Nossos resultados nos permitem afirmar que quatro fatores - dois associados a atributos individuais e dois associados a formas de manejo - atuam em conjunto para determinar a chance de cachorros visitarem remanescentes florestais em paisagens rurais da Mata Atlântica. Cachorros maiores, mais exploradores, que recebem mais incentivo a se movimentar e que passam menos tempo confinados têm maior chance de visitar remanescentes florestais. A maior importância de atributos individuais e da forma de manejo está de acordo com a grande variação fenotípica existente entre cachorros e a variedade de modos como são manejados. Entre os atributos individuais, tanto características físicas como comportamentais são importantes, enquanto os aspectos chave da forma de manejo são aqueles mais diretamente relacionados à movimentação dos cachorros. Independentemente do tempo de confinamento, o incentivo do dono à movimentação do cachorro, em particular o estímulo para que o cachorro o acompanhe em visitas a remanescentes florestais, é fundamental. O contexto ambiental, em especial a proximidade do domicílio a áreas de mata nativa, por sua vez, é irrelevante dada a alta mobilidade dos cachorros. Nossos dados sugerem que a densidade de cachorros em paisagens rurais de Mata Atlântica é uma ordem de magnitude mais alta do que a de carnívoros de médio porte silvestres relativamente comuns, que muitos cachorros já tiveram contato direto com espécies silvestres, e que a vacinação e outras medidas profiláticas são relativamente incomuns. Todos esses dados indicam o potencial de efeitos negativos, tanto para a fauna silvestre como para o homem. Programas de redução destes impactos devem incluir tanto aspectos veterinários, como a expansão de campanhas públicas de profilaxia para além da vacinação antirrábica, quanto aspectos sociais, como a divulgação e conscientização dos potenciais problemas ocasionados pela entrada de cachorros em áreas de vegetação nativa, visando mudanças nas crenças, atitudes e comportamento da população humana / Biological invasions are today the second greatest threat to biodiversity, and humans play a significant role in the introduction of potentially invasive exotic species. The dog (Canis lupus familiaris) is one of such species. Distributed across all continents, the dog is the most abundant carnivore in the planet, and can impact wildlife through lethal and non-lethal effects of predation, competition, hybridization and disease transmission, besides being potentially important in the epidemiology of zoonoses. In rural areas where most remnants of native vegetation around the world are concentrated, most dogs are free-ranging, enhancing the chance of interactions with wildlife. Here, we evaluated the relative importance of factors associated with individual traits (sex, age, health condition, exploratory behaviour, size and breed), management (owner\'s incentive to movement, motive for raising, confinement and feeding frequency), and environmental context (proximity to native forest) to determine the chance of dogs visiting forest remnants in Atlantic Forest fragmented landscapes. We selected eight landscapes of 2830 ha each, where we visited all constructions in rural areas in order to interview dog owners by applying a questionnaire and to photograph dogs. We used multiple imputation to estimate missing data (common in data obtained through questionnaires), obtaining 10 imputed datasets that were analyzed separately. We compared candidate models with up to five independent variables to determine the chance of dogs visiting forest remnants through the Akaike Information Criterion. Our results indicate that four factors - two associated with individual traits and two associated with management - work together to determine the chance of dogs visiting forest remnants in Atlantic Forest rural landscapes. Larger dogs, and those that exhibit exploratory behaviour, are more stimulated to move or confined for shorter periods have greater chance of visiting forest remnants. The greater importance of factors associated with individual traits and management is in accordance with the ample phenotypic variation among dogs and the variety of ways they can be managed. Among individual traits, both morphological and behaviour characteristics are important, whereas the key aspects of management are those directly related to dog movement. Irrespective of the time confined, the owner\'s incentive to movement, in particular taking the dog to the forest, is a crucial aspect. In contrast, the environmental context, especially the proximity of the household to native forest, is irrelevant given the vagility of dogs. Our results suggest that the density of dogs across rural landscapes in the Atlantic forest is at least one order of magnitude higher than the density of relatively common medium-sized native carnivores, that several dogs have already had direct contact with wild species, and that vaccination and other prophylactic measures are relatively uncommon. All of these highlight the potential for negative effects on both wildlife and human population. Plans to reduce these effects should include not only veterinarian aspects, such as the expansion of public prophylactic campaigns beyond rabies vaccination, but also social aspects, such as the dissemination of information on the problems caused by dogs visiting native vegetation, aiming at changing people\'s beliefs, attitudes and behaviour

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