Förlust av den biologiska mångfalden ökar i en allt mer accelererande fart än tidigare och många forskare varnar för att vi befinner oss inför det sjätte massutdöendet av arter. Med en fortsatt global uppvärmning och ett klimat som förändras blir allt fler arter utrotningshotade. För att hindra fortsatt förlust av biologisk mångfald har det uppstått olika typer av bevarandeprojekt och skydd av arter i form av direktiv, lagar och olika djurskyddsorganisationer. Vissa arter har även blivit utsedda till symbolarter för att de utrotningshotade arternas status ska uppmärksammas. I Sverige är fjällräven en art som är utrotningshotad och uppmärksammad av olika djurskyddsorganisationer. Denna uppsats är avgränsad till Sverige och fjällräven som art. Avsikten med uppsatsen är att ur ett miljöetiskt perspektiv undersöka individers attityder och åsikter som ligger till grund för individers vilja att bevara en art och att undersöka betalningsviljan och existensvärdet av fjällräven. Detta har undersökts och analyserats både kvantitativt och kvalitativt genom en enkätstudie. Uppsatsens resultat visar att fjällrävens status är uppmärksammad och att miljöetiska aspekter är viktiga för respondenternas vilja att bevara arten. Nyckelord: bevarande, Fjällräv (Vulpes lagopus), existensvärde, miljöetik, symbolart, betalningsvilja / Loss of biodiversity is increasing at an alarming accelerated pace than ever before and many researchers warn that we are facing the sixth mass extinction of species. With continued global warming and a changing climate, more species are becoming endangered. In order to prevent continued loss of biodiversity, various types of conservation projects and protection of species in the form of directives, laws and various animal welfare organizations have arisen. Some species have also been designated as symbolic species in order to highlight their endangered status. In Sweden, the arctic fox is a species that is endangered and attracts attention by various animal welfare organizations. This essay is limited to Sweden and the arctic fox as a species. The purpose of this essay is to investigate and analyze individuals attitudes and opinions from an environmental ethical perspective and to examine the willingness to pay and the non-use value of the arctic fox. This has been investigated and analyzed both quantitatively and qualitatively through a survey. The results of the thesis show that the status of the arctic fox is highlighted and that environmental ethical aspects are important for respondents’ willingness to preserve the species.Keywords: conservation, Arctic fox (Vulpes lagopus), non-use value, environmental ethics, symbolic species, willingness to pay

Bank voles, grey-sided voles, and field voles had synchronous 3-4 year density cycles with variable amplitudes which averaged about 200-fold in each species. Cycles of vole predators (red fox and Tengmalm's owl), and their (foxes') alternative prey (mountain hare and forest grouse) lagged behind the vole cycles. The nomadic Tengmalm's owl responded with a very rapid and strong numerical increase to the initial cyclic summer increase of voles (the owl’s staple food). Owl breeding densities in the springs were highly correlated with vole supply in the previous autumns. This suggested that the number of breeding owls was largely determined in the autumn at the time of the owl's nomadic migrations, and that immigration was crucial for the rapid rise in owl numbers. The owl's numerical response was reinforced by the laying of earlier and larger clutches when food was plentiful. In addition, the owl has an early maturation at one year of age. The transition between subsequent vole cycles was characterized by a distinct shift in rate of change in numbers from low to high or markedly higher values in both summer and winter. Regulation increased progressively throughout the cycle since the rate of change decreased continuously in the summers. Moreover, there was a similar decrease of the rate of change in winter. Rate of change was delayed density-dependent. The delayed density-dependence had an 8 month time-lag in the summers and a 4 month time-lag in the winters relative to the density in previous autumns and springs, respectively. These findings suggest that vole cycles are likely to be generated by a time-lag mechanism. On theoretical grounds, it has been found that a delayed density- dependence of population growth rate with a 9 month time-lag caused stable limit cycles with a period between 3 and 4 years. Some mechanisms for the delayed density-dependence are suggested and discussed. The mechanisms are assumed to be related to remaining effects of vole populations past interactions with predators, food supplies, and/or diseases. Unlike the other voles, the bank vole had regular and distinct seasonal declines in density over winter. These declines are proposed to be due to predation, mainly by Tengmalm's owl. Supranivean foraging for epiphytic tree lichens and conifer seeds most likely explains why this species was frequently taken by the owl under snow-rich conditions. The alternative prey hypothesis predicts that a reduction of predator numbers should increase the number of alternative prey. Alternative prey should be less effectively synchronized to the vole cycle by predation at declining and low vole (main prey) densities; they may also lose their 3-4 year cyclicity. The appearance of sarcoptic mange among foxes in northern Sweden in the mid 1970s provided an opportunity to "test" these ideas, and these were found to be supported. In areas with highest mange infection rates, foxes declined markedly from the late 1970s to mid 1980s, whereas hare numbers rose rapidly and appeared non-cyclic. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1991, härtill 7 uppsatser</p> / digitalisering@umu

The human use of landscape causes fragmentation and loss of original habitats. Different species vary in their sensitivity to habitat loss. Especially carnivores can be more sensitive to decrease of their habitat because of lower abundance of their prey. On the other hand several opportunistic carnivores can profit in human modified habitats. This study was carried out in the České Budějovice basin, Czech Republic during the years 2008 and 2009 and the aim of this study was to determine carnivore{\crq}s habitat preferences in the fragmented landscape. During these two years were seven carnivore species monitored in forest patches by using scent stations. Records of this monitoring were compared with physiognomy of these patches and structure of surrounding landscape.