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Movement pattern of Moose (Alces alces) in southwestern Sweden in relation to highway traffic intensityHenriksson, Lars-Henrik January 2007 (has links)
<p>Abstract</p><p>GPS telemetry is a method with good accuracy to determine animal movements in the terrain. It is necessary to determine locations of free-ranging animals in order to understand movement patterns and habitat use, and to understand the consequences of human impacts like highways. This study aims to describe moose movement patterns and to evaluate the effect of highway traffic intensity on moose movements across a highway.</p><p>Moose in Southwestern Sweden have different movement rates throughout the year. Increased movement rate for females was observed during spring and summer. The breeding season (15 September -15 October) is the most important season for bulls. Our result shows that bulls significantly increase their movement rate during the rut, compared to other times during the fall. Movement rate increased twice compared with female movement rate during this period. No difference was observed during the rutting period for females (15 September- 15 October) compared with no rutting period during fall. During winter time, both sexes retain low movements, mainly caused by energy saving actions. A distinct crepuscular rhythm was exhibited during the summer and fall season, movements were more intense during dawn and dusk hours. No distinct crepuscular rhythm was noticed during winter and spring seasons.</p><p>The traffic intensity at highway E6 in Southwestern Sweden increases during the morning hours and reaches its maximum during midday. Moose in southwestern Sweden crossed highway E6 more often at night time than day time. Thus highway crossings by moose occurred at times of peak moose movements, and traffic volume had lower importance.</p>
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Movement pattern of Moose (Alces alces) in southwestern Sweden in relation to highway traffic intensityHenriksson, Lars-Henrik January 2007 (has links)
Abstract GPS telemetry is a method with good accuracy to determine animal movements in the terrain. It is necessary to determine locations of free-ranging animals in order to understand movement patterns and habitat use, and to understand the consequences of human impacts like highways. This study aims to describe moose movement patterns and to evaluate the effect of highway traffic intensity on moose movements across a highway. Moose in Southwestern Sweden have different movement rates throughout the year. Increased movement rate for females was observed during spring and summer. The breeding season (15 September -15 October) is the most important season for bulls. Our result shows that bulls significantly increase their movement rate during the rut, compared to other times during the fall. Movement rate increased twice compared with female movement rate during this period. No difference was observed during the rutting period for females (15 September- 15 October) compared with no rutting period during fall. During winter time, both sexes retain low movements, mainly caused by energy saving actions. A distinct crepuscular rhythm was exhibited during the summer and fall season, movements were more intense during dawn and dusk hours. No distinct crepuscular rhythm was noticed during winter and spring seasons. The traffic intensity at highway E6 in Southwestern Sweden increases during the morning hours and reaches its maximum during midday. Moose in southwestern Sweden crossed highway E6 more often at night time than day time. Thus highway crossings by moose occurred at times of peak moose movements, and traffic volume had lower importance.
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Determination Of Home Range Size And Habitat Selection Of Gazelles (gazella Subgutturosa) By Gps Telemetry In SanliurfaDurmus, Mustafa 01 February 2011 (has links) (PDF)
Goitered gazelle is one of the threatened species of Turkey living in only & / #289 / anliurfa region. In this study, goitered gazelles have been released to their previous habitat in Sanliurfa-Suruç / region and seven of females were collared with GPS collars. These individuals were monitored for a year and their seasonal habitat selection and home range sizes are determined by using location data recorded on the collars. In addition to 4 seasons of the year, home range and habitat selection are estimated for mating and calving periods. Also, summer period is divided to two as summer1 and summer 2 because of changing availability of water resources in study area. Seasonal home range sizes of GPS collared gazelles are estimated as average 3.61 ± / 0.47 km2 for winter, 3.96 ± / 0.44 km2 for spring, 4.55 ± / 1.35 km2 for summer1, 2.26 ± / 0.20 km2 for summer2, 3.38 ± / 0.44 km2 for autumn, 1.37 ± / 0.50 km2 for mating season, and 1.66 ± / 0.50 km2 for calving season.Seven habitat variable layers were prepared for the evaluation of seasonal habitat selection of GPS collared female gazelles. Gazelles were selected east aspects in summer and west aspects in winter seasons and, north and flat aspects were avoided in all seasons for a year. Water can be considered the key habitat variable for the goitered gazelles. The results show that some home ranges are outside of the protected area and gazelles do not use large areas in the protected area. In order to improve conservation of gazelles, protected area should be re-arranged and shifted to more intensely used areas by gazelles.
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Mění se denní aktivita jelenů evropských (\kur{Cervus elaphus}) během migrací v NP Šumava a NP Bavorský les? / Is the daily activity of red deer (\kur{Cervus elaphus}) different during migrations in National park Šumava and Bayerisher Wald?HUBENÁ, Zuzana January 2011 (has links)
This thesis deals with a migration and other movements of red deer (Cervus elaphus) in the Šumava mountains. I analysed several parameters of migrations such as distance, pace, and timing of activity/movements in both sexes. I also analysed annual and daily activity rhythms and changes of daily activity during migrations and other movements.
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Spatial Ecology of Bobcats (Lynx rufus) in the Appalachian Mountains of Western VirginiaMcNitt, David C. 27 August 2019 (has links)
Despite the prevalent distribution of bobcats in western Virginia and the broader region of Appalachia, there is a paucity of information on their spatial ecology in this region. Due to the unique ecological conditions of Appalachia, and increasing public interest surrounding the role of bobcats as predators in the region, there is a need for local information on bobcat ecology. I utilized data from 20 GPS collared bobcats (14M, 6F) to investigate bobcat spatial ecology in the mountains of Western Virginia. Average resident male home range size was 33.9 ± 2.6 km^2, nearly 3 times larger than average resident female home range size (12.1 ± 2.4 km^2). Seasonal areas of use did not differ in size among seasons, but exhibited minor shifts in location and shape. Average male movement rates (232.3 ± 12.0 meters/hour) were 1.5 times greater than average female movement rates (154.4 ± 8.9 meters/hour). Male movement rates increased during the dispersal season and female movement rates increased during the denning/kitten-rearing season. Second order resource selection analysis indicates that bobcats of both sexes select home ranges at higher elevations than expected at random, and that selection varies between sexes and among seasons. Third order resource selection analysis indicates that bobcats select for locations near open canopy structure, and avoid forest interior. These findings build upon previous findings regarding bobcat diet and population dynamics to provide a comprehensive understanding of basic bobcat ecology in western Virginia, and will inform further research investigating predator/prey interactions. / Master of Science / Despite the prevalent distribution of bobcats in western Virginia and the broader region of Appalachia, there is a paucity of information on their spatial ecology in this region. Due to the unique ecological conditions of Appalachia, and increasing public interest surrounding the role of bobcats as predators in the region, there is a need for local information on bobcat ecology. I utilized data from 20 GPS collared bobcats (14M, 6F) to investigate bobcat spatial ecology in the mountains of Western Virginia. I found that male bobcats use more space than females, with home ranges nearly 3 times larger and movement rates 1.5 times higher. I found that home ranges do not expand or contract throughout the year, but do shift in shape slightly. I found that bobcats select home ranges at higher elevations, indicating that home ranges are predominantly located on ridges. I found that selection of home ranges differed between sexes and seasons, indicating that shifts in home range shape throughout the year reflect varying habitat selection. Within their home ranges, I found that bobcats select for areas of open canopy resulting from fields, fire, and timber harvest; and avoid areas of forest interior. These findings build upon previous findings regarding bobcat diet and population dynamics to provide a comprehensive understanding of basic bobcat ecology in western Virginia, and will inform further research investigating predator/prey interactions.
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Facteurs influençant les stratégies de recherche alimentaire des oiseaux marins : une approche comportementale / Factors affecting searching strategies of foraging seabirds : a behavioral approachCollet, Julien 18 October 2018 (has links)
Comprendre les décisions prises par les organismes pour s’approvisionner en nourriture est essentiel pour anticiper leurs réactions aux changements de l’environnement. Les oiseaux marins en reproduction partent s’alimenter en mer depuis leur colonie. L’utilisation de GPS miniatures révèle qu’ils effectuent des trajets de dizaines jusqu’à des milliers de kilomètres en quête de proies pour lesquelles nous disposons de très peu d’informations. Les stratégies comportementales qu’ils utilisent pour augmenter leurs chances de rencontrer des proies dans l’environnement marin, et les implications que cela peut avoir vis-à-vis des activités humaines de pêche qui semblent attirer de nombreux oiseaux sont encore très partiellement comprises. Cette thèse propose de réexaminer ces questions en trois chapitres, à travers des simulations théoriques, l’analyse empirique de trajets enregistrés par GPS sur diverses espèces et populations d’oiseaux marins, et le croisement des trajets simultanés d’oiseaux et de bateaux de pêche. Premièrement, les simulations théoriques de marches aléatoires montrent qu’on ne peut pas se servir des phases de ligne droite dans un trajet pour conclure si les oiseaux anticipent où sont leurs proies, ce qui vient nuancer les conclusions de nombreuses études précédentes. L’analyse des biais dans les directions suivies par les oiseaux permet en revanche de comprendre les informations qu’ils utilisent pour décider où s’approvisionner. Deuxièmement, les stratégies de fidélité spatiale individuelle sont comparées entre espèces, populations et contextes écologiques à l’aide de modèles statistiques multivariés (GLMM). De nombreux oiseaux marins font en effet preuve de fidélité individuelle dans la direction qu’ils prennent pour s’approvisionner depuis la colonie, suggérant l’utilisation de mémoire. Nous montrons que c’est également le cas de nombreuses populations et espèces d’oiseaux marins tropicaux, qui restent fidèles à une direction pendant plusieurs jours successifs. Ces résultats sont surprenants et difficiles à expliquer car la plupart des espèces étudiées ciblent des proies très dynamiques et disponibles à un endroit de façon très éphémère. Cela suggère que la mémoire pourrait être plus fréquemment utilisée par les oiseaux marins que ce que l’on supposait, au moins à large échelle spatiale. Finalement, nos analyses sur les réponses des albatros aux bateaux de pêche suggèrent que les albatros modulent leurs réponses en fonction de l’espèce et des contraintes énergétiques, et que les rencontres de bateaux ont peu d’influence sur les stratégies suivies par les individus lors de leur trajet suivant. Ainsi le comportement d’attraction aux bateaux de pêche pourrait être un phénomène local (à l’échelle du rayon de perception) et largement opportuniste. Globalement, nos résultats empiriques ancrés dans un socle théorique solide suggèrent que l’approvisionnement des oiseaux marins ne peut pas se résumer à rencontrer des ressources rares et imprévisibles, et semble pouvoir impliquer des processus de sélection des ressources rencontrées et/ou de choix entre utilisation de mémoire individuelle ou d’information publique. Les ressources anthropiques à ce titre pourraient ne constituer que des ressources parmi d’autres. De nombreux outils d’analyses utilisés ici sont facilement transférables à d’autres oiseaux marins ou d’autres prédateurs à place centrale. Élargir les comparaisons à d’autres organismes est en effet nécessaire pour mieux comprendre les variations complexes mises en évidence ici dans la plasticité comportementale et leurs conséquences vis-à-vis des changements environnementaux. / It is essential to understand how animals make foraging decisions to acquire food in order to better anticipate their responses to environmental changes. Breeding seabirds make central-place foraging trips at sea, from their colony. The deployment of small GPS devices on them reveals that they travel for tens to thousands of kilometers, in search of prey for which very little information is known. The behavioural strategies they use to increase their chances to encounter prey, and the implications of these strategies with regards to human fishing activities remain open questions. This thesis offers to examine these questions in three chapters, through theoretical simulations, empirical analyses of foraging trips of various species and populations of seabirds, and the spatiotemporal matching of seabirds and fishing vessels movements. First, our random walk simulations indicate that straight-line phases within path are not sufficient to conclude that seabirds anticipate where to find their prey, contrary to previous conclusions proposed in the literature. However it is possible and easy to analyze biases in the directions individuals follow when they forage, to infer which sources of information they use to decide where to forage. Second, we compare individual fidelity strategies between species, populations and/or ecological contexts through the use of multivariate statistical models (GLMM). Many seabirds display individual fidelity in the direction they forage from the colony, suggesting they rely on memory. Our results show that this is also the case in different species and populations of tropical seabirds, where individuals can remain faithful to a foraging direction for several consecutive days. These results are surprising and difficult to explain as the species we studied are targeting prey whose distribution is supposedly very stochastic and ephemeral. It suggests that the use of memory might be much more widespread in foraging seabirds than anticipated, at least for decisions at large spatial scales. Finally, our analyses on the responses of albatrosses to fishing boats suggest that their responses can be modulated according to species and energetic constraints, and that encounters of fishing boats during a foraging trip have little influence on the strategy used by individuals on their next foraging trip. The attraction of albatrosses to boats might be mainly a local process (at the scale of the perception range) and may be largely opportunistic. Overall, our empirical results anchored in a solid theoretical framework suggest that seabird’s foraging cannot be summarized as encountering rare and unpredictable resources, but might imply resource selection processes after resources are encountered, and/or a decision as to rely either on memory or public information. With that regard, anthropic resources may only be one type of resources among others for seabirds. Many of the analytical tools used here could be transferred to other seabirds and other central place foragers. Indeed, a wider comparative approach is necessary to understand the complex variations in behavioural plasticity observed here, and their consequences regarding future environmental changes.
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A multi-scale assessment of spatial-temporal change in the movement ecology and habitat of a threatened Grizzly Bear (Ursus arctos) population in Alberta, CanadaBourbonnais, Mathieu Louis 31 August 2018 (has links)
Given current rates of anthropogenic environmental change, combined with the increasing lethal and non-lethal mortality threat that human activities pose, there is a vital need to understand wildlife movement and behaviour in human-dominated landscapes to help inform conservation efforts and wildlife management. As long-term monitoring of wildlife populations using Global Positioning System (GPS) telemetry increases, there are new opportunities to quantify change in wildlife movement and behaviour. The objective of this PhD research is to develop novel methodological approaches for quantifying change in spatial-temporal patterns of wildlife movement and habitat by leveraging long time series of GPS telemetry and remotely sensed data. Analyses were focused on the habitat and movement of individuals in the threatened grizzly bear (Ursus arctos) population of Alberta, Canada, which occupies a human-dominated and heterogeneous landscape. Using methods in functional data analysis, a multivariate regionalization approach was developed that effectively summarizes complex spatial-temporal patterns associated with landscape disturbance, as well as recovery, which is often left unaccounted in studies quantifying patterns associated with disturbance. Next, the quasi-experimental framework afforded by a hunting moratorium was used to compare the influence of lethal (i.e., hunting) and non-lethal (i.e., anthropogenic disturbance) human-induced risk on antipredator behaviour of an apex predator, the grizzly bear. In support of the predation risk allocation hypothesis, male bears significantly decrease risky daytime behaviours by 122% during periods of high lethal human-induced risk. Rapid behavioural restoration occurred following the end of the hunt, characterized by diel bimodal movement patterns which may promote coexistence of large predators in human-dominated landscapes. A multi-scale approach using hierarchical Bayesian models, combined with post hoc trend tests and change point detection, was developed to test the influence of landscape disturbance and conditions on grizzly bear home range and movement selection over time. The results, representing the first longitudinal empirical analysis of grizzly bear habitat selection, revealed selection for habitat security at broad scales and for resource availability and habitat permeability at finer spatial scales, which has influenced potential landscape connectivity over time. Finally, combining approaches in movement ecology and conservation physiology, a body condition index was used to characterize how the physiological condition (i.e., internal state) of grizzly bears influences behavioral patterns due to costs and benefits associated with risk avoidance and resource acquisition. The results demonstrated individuals in poorer condition were more likely to engage in risky behaviour associated with anthropogenic disturbance, which highlights complex challenges for carnivore conservation and management of human-carnivore conflict. In summary, this dissertation contributes 1) a multivariate regionalization approach for quantifying spatial-temporal patterns of landscape disturbance and recovery applicable across diverse natural systems, 2) support for the growing theory that apex predators modify behavioural patterns to account for temporal overlap with lethal and non-lethal human-induced risk associated with humans, 3) an integrated approach for considering multi-scale spatial-temporal change in patterns of wildlife habitat selection and landscape connectivity associated with landscape change, 4) a cross-disciplinary framework for considering the impacts of the internal state on behavioural patterns and risk tolerance. / Graduate
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Breeding and foraging ecology of Caspian terns nesting on artificial islands in the Upper Klamath Basin, CaliforniaPatterson, Allison (Allison Glider) 13 November 2012 (has links)
Availability of suitable nesting habitat that is free of nest predators and provides access to adequate prey resources within commuting distance is a major factor limiting seabird populations. Caspian terns (Hydroprogne caspia) in western North America have shifted their breeding habitat from naturally occurring habitats in interior wetlands, lakes, and rivers to primarily human-created habitats in coastal bays and estuaries. This shift has brought Caspian terns into conflict with fisheries of conservation concern, in particular anadromous salmonids. Prior to the 2010 breeding season, three artificial islands were built in the Klamath Basin National Wildlife Refuge (NWR) Complex as alternative nesting habitat for Caspian terns currently nesting at the world's largest colony for the species, near the mouth of the Columbia River, Oregon.
I investigated the efficacy of habitat creation (island building) and social attraction (decoys and recorded vocalizations) for establishing new breeding colonies in the Upper Klamath Basin, California. In 2010, approximately 258 pairs of Caspian terns attempted to nest on the new islands and raised an average of 0.65 fledglings/breeding pair; in 2011, 222 pairs attempted to nest and raised an average of 0.11 fledglings/breeding pair. Competition with California and ring-billed gulls (Larus californicus and L. delawarensis) for nesting space, gull predation on Caspian tern eggs and chicks, low water levels, and depredation by great horned owls (Bubo virginianus) were the primary factors limiting colony development and productivity, especially in 2011. The immediate response by Caspian terns to habitat creation and social attraction in the Upper Klamath Basin demonstrates that these can be effective restoration techniques to establish new breeding colonies where nesting habitat is a major limiting factor; however, continued management of other limiting factors (e.g., control of on-colony predators and competitors) will likely be necessary to promote the development of established, self-sustaining breeding colonies on these artificial islands.
Efforts to conserve and restore seabird colonies can be compromised by low prey availability within foraging distance of the breeding colony. I used GPS telemetry to study the fine-scale foraging behavior of Caspian terns nesting at two newly established colonies and cluster analysis to discriminate behavioral states based on movement characteristics. Terns breeding at the Sheepy Lake colony spent less time at the colony (52% of the day) than terns breeding at the Tule Lake colony (74%). Caspian terns breeding at Sheepy Lake foraged more extensively than terns breeding at Tule Lake; the foraging trips of Sheepy Lake terns lasted longer (median = 186 min) and were longer-distance (27 km) compared to those of Tule Lake terns (55 min and 6 km, respectively). Between-colony differences in foraging behavior corresponded to 5% lower average body mass of breeding adults and significantly lower size-adjusted body mass of chicks at the Sheepy Lake colony compared to the Tule Lake colony. Proximity to high-quality foraging areas influenced the foraging behavior and parental care of breeding Caspian terns, which in turn had effects on nesting success. The successful use of GPS telemetry to study the fine-scale foraging behavior of Caspian terns represents a significant advance in our ability to investigate the foraging ecology of this species and other moderate-sized seabirds. / Graduation date: 2013
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