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14 Uppsatser om Ursus arctos - Sida 1 av 1

The influence of forestry stands treatments on brown bears (Ursus arctos) habitat selection in Sweden ? an option for Alberta forestry?

The brown bear population in Alberta, Canada has been decreasing, while the Swedish has been increasing and all the affecting parameters are not known. This study examined the difference in these populations to see if an explanation could be found in differences between the forest management. The aim of the paper was to see if stand treatments had an influence of brown bears habitat selection in autumn in Sweden and how the results can be used in Alberta. This was done by analyzing bear positions in Sweden with forest data, and comparing forest management data for the study area in Sweden with forest management data for Alberta. The results displayed that mature forests over 60 years that have been commercially thinned are selected by bears rather than forests over 60 years that have not been commercially thinned in.

Patologiska förändringar och säsongsmässiga variationer i testiklar från svenska brunbjörnar (Ursus arctos) :

Functioning reproductive organs are essential for the survival of a species. The reproductive system is very sensitive to exposure of chemical substances of anthropogenic origin. Humans release great amounts of chemical substances to the environment by our means of life and these substances have been proved to have a negative effect on the reproductive ability of different vertebral classes. In the polar bear (Ursus maritimus) a declined reproductive ability as an effect of decreased testosterone levels and decreased testicular size has been connected to the presence of high levels of organohalogenic compounds like PCBs. Although the Swedish brown bear (Ursus arctos) is not as carnivorous as its close relative the polar bear it is still exposed to environmental.

Brunbjörnens (Ursus arctos) inverkan på den nya svenska älgförvaltningen

The European Brown bear (Ursus arctos) has gone from basically being extinct in Sweden to, 2008 being estimated to a total of 3298 individuals. When looking at the new Swedish moose management system it is important to have an ecosystem-based approach and therefore include all the parts that moose impacts on and from in the management, especially the brown bear. Primarily in the spring and early summer the brown bear is a significant predator on moose calfs which must be taken into account in moose management. When the bear recolonize areas that it has previously been eradicated from, it will once again come in contact with people who are not accustomed to the bear's role in the ecosystem. We studied three groups of moose management areas with different predation by bears.

Vilka stereotypier finns hos brunbjörn (Ursus arctos), lodjur (Lynx lynx) och varg (Canis lupus) i djurpark och vilka berikningar finns? : förslag och rekommendationer om berikningar utifrån djurens beteendeekologi

The purpose of this work was that with the help of a literature review have a single document with information on how the various species: brown bear (Ursus arctos), lynx (Lynx lynx) and the wolf (Canis lupus) living in the wild. The aim was also to show which stereotypic behaviours these different species have in zoos and the enrichments that is already being used and to make suggestions and recommendations on enrichment based on animal behaviour ecology. In zoos, some species thrive well while others have propositions to propagating problems, poor health and stereotypic behaviors. The brown bear, lynx and wolf, live both in the wild and in zoos in Sweden. As these animals have different ways of living in the wild, it is important to accommodate to each species, the way they are kept in zoos in accordance with their behavioural ecology.Brown bears are omnivorous and solitary living species with large energy needs so that they spend most of their day to actively feeding but also rest.

Effects of brown bear (Ursus arctos) odour on the patch choice and behaviour of different ungulate species

The return of large predators to regions where they were previously extirpated has created a need for knowledge about their effect on prey species, not only their lethal but also their behavioural or risk effects. In this study the behavioural risk effects of brown bear (Ursus arctos) were tested on fallow deer (Dama dama), roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and wild boar (Sus scrofa). This was done by using patches of fur to simulate the presence of the novel predator (brown bear), a novel nonpredator (reindeer (Rangifer tarandus) and no fur as control. These three treatments were then compared. The response variables measured were increased vigilance, decreased feeding time and change in patch use.

Utveckling av biopsiinstrument : Instrumenthållare för skruvnålsbiopsi

This Master Thesis has been carried out in cooperation with Ursus Medical AB (URSUS) which markets, assembles and sells the Rotex Screw Needle Biopsy Instrument ®. The instrument is delivered with an instrument holder. Customers had expressed dissatisfaction over that they needed to use two hands during a biopsy procedure, which resulted in a project to develop a new instrument holder.The project aim was to create concepts for how the new instrument holder should be designed, with focus on the mechanics. The new instrument holder would build on the existing basic principle that the screw needle and the cannula were screwed into the tissue. The thesis work would result in a technical solution and a functional prototype of the chosen concept.To achieve this, a generic product development processes were used and began with a comprehensive literature review.

Dental and periodontal health in free-ranging Swedish brown bears (Ursus arctos)

Det Skandinaviska Björnprojektet har arbetat med samma björnpopulationer sedan 1984. Detta ger en unik möjlighet att över tid följa samma individer och population och därmed se eventuella förändringar som sker med dessa. Under april och maj 2008, som en del av det Skandinaviska björnprojektets årliga sövningar och märkningar av brunbjörn (Ursus arctos), undersöktes tand- och munhälsan hos 22 björnar med varierande ålder och kön. Alla björnarna vägdes och undersöktes kliniskt. Munhålan inspekterades och fotograferades.

Effektivisering av urvalsprocesser vid analysering av björnspillning : Ett förslag till den svenska förvaltningen av brunbjörn Ursus arctos

The aim with this report is to formulate a strategic method to optimize selection processes of DNA-samples from a faeces inventory to identify as many individuals in as few analyzes as possible, and by that keep down the costs of brown bear management. Brown bear management in Sweden founds today on results from faeces inventory and is substantially led by the county administration boards. Data from the years of 2004 and 2009´s inventories in Västerbotten was used to test and evaluate different methods in selection processes of which faeces that should be sampled. Comparison were made between making selection by chance, by spatial distribution and by calculating variations in logistic regressions coefficient b, in other words bear density and probability in finding same individual in several faeces. We can show making selection by chance is the most uncertain method.

Attacks on humans in Sweden by bear, wolf, lynx, wolverine, moose and wild boar in relation to Swedes? fear for these animals

It is not easy to understand people?s fears since they are not always a logical reflection of the danger in certain situations. This study is an attempt to give a scientific view of the potential danger that certain animals in Sweden pose and compare this to Swedes? fear of these animals. A report shows that Swedes? have a certain amount of fear for being attacked by a wild animal in the forest and this fear has increased for certain animals over the last years.

Hur påverkar licensjakt björnstammens (Ursus arctos) tillväxt i Gävleborgs län?

Licensjakt på brunbjörn har varit tillåten i Gävleborgs län i mer än ett decenium, samtidigt kan jakt påverka populationstillväxten stark eftersom björnar har en naturligt låg dödlighet. Detta gör det viktigt att förstå hur kön och ålder hos de fällda björnarna påverkar populationens framtida tillväxt. Syftet med denna studie var att studera befintlig littertur om björn i Gävleborgs län, analysera data om björnar fällda genom licensjakt och att, med hjälp av populationsmodell, ta reda på hur populationen utvecklas vid olika jakttryck. Senare användes en populationsmodell för att ta reda på hur populationen utvecklas vid olika jakttryck. På grund av att honor har större påverkan på populationers överlevnad tog modellen enbart hänsyn till björnhonor och deras ålder, reproduktion och överlevnad över tid. Resultaten i studien har tagits fram genom olika scenarion som skapats i modellen. Könsfördelningen hos fällda björnar under perioden 2001-2012 var jämn och flest honor (28,7%) hade fällts vid två till tre års ålder.

Brown bear (Ursus arctos) den site concealment in relation to human activity in Scandinavia

As a hibernating species, the brown bear spend most of the winter months in a den as astrategy to avoid unfavorable conditions. The denning period is a vulnerable time for bears,making them unable to flee disturbances without losing valuable amounts of energy. Brownbears' wariness of humans and avoidance of anthropogenic disturbance often steer denningbears away from human infrastructure, and bears thereby avoid possible disturbance and itsassociated energetic costs. This study was carried out to test the hypothesis that bearsdenning closer to infrastructure select more covered den sites to compensate for the closedistance. Dens from 32 individuals were visited and analyzed in terms of sighting distance(a measurement for den horizontal cover) and habitat ruggedness, in relation to distances toinfrastructure.

Do grizzly bears use or avoid wellsites in west-central Alberta, Canada?

The purpose of this report is to make an evaluation of the self-monitoring for scarification which Stora Enso is using and this study deals with the effects and importance of scarification. A comparison is made in this study with the purpose to highlight any differences between some of the leading forestry companies and significant forest organizations in Sweden. The companies represented in this report are Korsnäs, Mellanskog, SCA, Sveaskog and Södra. In the beginning of this study an interview form was set up together with Daniel Forsberg at Stora Enso. Stora Enso is the head object of this report and seven interviews were made within that company. At the other companies only three interviews were made within each one, with an exception to Mellanskog who wished four.

Miljökemikaliers påverkan på isbjörnars (Ursus maritimus) reproduktion och hur dessa kemikalier når djuren

Environmental chemicals are transported to the Arctic through the air and oceans, once within the Arctic they spread through rivers, lakes and other watercourses. Polar bears and sledge dogs in-gest high concentrations of environmental chemicals since many of the chemicals are fat-soluble and their diet mainly consists of marine mammals. The aim of this study is to describe how environmental chemicals spread in nature, how they reach the polar bears, and finally how they affect the animals reproduction, with reproductive hormones and genitals in focus. The animals are exposed to a cocktail effect which complicates the assessment of the chemicals impact on the reproduction. Studies show that the genitals can decrease in size or become malformed, sexual maturation can be affected and the reproductive hormones can be disturbed.

Isbjörnars (Ursus maritimus) interaktioner och hägnutnyttjande på Orsa björnpark

SAMMANFATTNINGIsbjörnen är mycket populär hos djurparksbesökare och en viktig symbol för klimathotet, trots detta finns fortfarande många frågetecken kring hur vi ger isbjörnar i djurparker hög välfärd. I litteraturen har vi länge talat om isbjörnar som solitära djur men trots detta låter vi dem ofta dela hägn med andra isbjörnar på djurparker. Det har observerats positiva effekter av grupphållning av isbjörnar, bland annat sänkt förekomst av stereotypa beteenden, men vi måste vidare utreda vilken påverkan det har på deras välfärd. Ytterligare problem för isbjörnar på djurparker är stereotypt vankande som har observerats hos flertalet karnivorer som i det vilda rör sig över stora områden eller hemytor. Syftet med denna studie var att titta på hur isbjörnarna på Orsa björnpark utnyttjar sitt hägn, vilka beteenden som kan observeras samt hur stor del av observationerna de spenderar tillsammans.