During the 1960´s and 1970´s the number of grey seals in the Baltic Sea was decreasing rapidly, mostly due to hunting and toxic substances like DDT and PCB. When hunting became less intense and toxic substances decreased in the environment the grey seal population started to increase. Today grey seals are found common in the Baltic Sea and have started to become a big treat and a problem to the fishing industry. The grey seal destroys and enters fishing traps and consumes large quantities of the fish that have been caught.The knowledge of the grey seal, like abundance and food preferences, is today limited. It is also important to define the position of the grey seal in the ecosystem in the Baltic Sea and to be able to predict changes that could occur if the population would rapidly decrease or increase.

Sammanfattning: Liljebaggen, Lilioceris lilii (Scopoli) är den största skadegöraren på liljor tillhörande släktena Lilium och Fritillaria, och är ett problem i Sverige liksom i övriga Europa, Nord-Amerika och Asien. Skadan orsakas främst av larverna, men även av fullvuxna baggar, som äter på plantans blad, knoppar och blommor (Ernst, 2005). De kan orsaka allvarliga skador genom att äta upp alla blad på plantan (Gold et al., 2001; LeSage and Elliott, 2003). Biologisk bekämpning i Sverige verkar möjlig sen man har upptäckt parasitsteklar som attackerar liljebaggens ägg och larver i Europa. I de centrala delarna av Europa har Haye och Kenis (2004) funnit fyra arter av parasitsteklar som parasiterar liljebaggens larver, ichnemoniderna Lemophagus pulcher, Lemophagus errabundus, Diaparsis jucunda, och eulopiden Tetrastichus setifer. En äggparasit, mymariden Anaphes har också upptäckts, liksom hyperparasiten Mesochorus lilioceriphilus, en ichneumonid, som ofta parasiterar Lemophagus arterna. För att undersöka förekomsten av dessa steklar i Sverige gjordes insamlingar av liljebaggslarver under sommaren 2006 på olika platser i tre regioner, södra (Skåne), sydöstra (Småland och Öland) och mellersta (Stockholm) Sverige.

Borna disease virus (BDV) is a virus with capability to cause neurological disease in several species of mammals and of ostriches. Also humans are suspected to be susceptible to the virus, as the viral RNA and antibodies against BDV have been found in some humans with psychiatric diseases, like schizophrenia and depression. In Sweden there is a disease called staggering disease in cats, associated to BDV-infection. This disease often has a fatal progress. Definite diagnosis is reached by histo-pathological and immunohistochemical examination of the central nervous system.

Many species and hence biodiversity depend on old, large oaks (Quercus robur) with hollow trunks. The populations of oak-living organisms have to migrate to a nearby old oak in order to survive the death of the host. The oak district south of Linköping, Sweden, is unique in area and the number of old oaks. It is anyway doubtful whether regeneration of oak will secure future continuity. Oaks are light-demanding and thrive in open pastures.

In this essay dog as a compatible model were put against human. The major histocompatibility complex (MHC) genes were compared between dogs, human, cat and mouse. To evaluate dog as a model and study similarities and differences was the aim with this review. Dog as a model contributes to understand mechanisms behind autoimmune diseases and showed clearly histological similarities between human and dogs concerning the skin disease mucous membrane pemphigoid (MMP)/cicatricial pemphgioid (CP). Further genetic evidence motivated the choice of using dog as a comprehensive model when the MHC-complex correlated with hypothyroiditis in Doberman dog as it does in human. Physiological similarities with low levels of thyroid hormones (T3 and T4) together with high level of thyroid releasing hormone (TSH) were found in the same way as in human.

The subject of this bachelor-level thesis in archaeology in the transition from archaic sapiens to anatomically modern humans, and what might have caused this transition. A part of the study aims to prove or disprove whether an increased consumption of shellfish might have caused this development. Another part of the essay deals with the connection of said evolution and the suggested emergence of cultural and ritual practices in South Africa circa 100 000 BP and an evaluation of the arguments concerning the aquatic ape hypothesis, and their usefulness for the subject.The result of investigation of the theory about the increased consumption of marine resources as a probable cause of the last biological step of creating our species points to the conclusion that it is a probable explanation. There is even some evidence that there could be a connection between consumption of marine resources and the "Out of Africa 2"-theory. It is harder to find a proven connection between the suggested emergence of cultural and ritual practices, even some evidence seems to strengthen the idea.

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.

A new Swedish political approach to forestry was initiated 1993, that put goals of production and environmental issues into equal importance to Swedish Forestry Law. Earlier nature conservation very often declaimed preservation the best way to conserve nature, but recently it is clear that many highly biological values are due to former land use or disturbance. Many old pastures or cultivations dominated by deciduous trees are today characterized by a dense overgrowth of Norway spruce. By actively paying attention to nature in forestry (nature restoration), it is possible to partly reconstruct habitats or disturbances that are necessary to favour the biological values. The aim with this master thesis is to study the nature restoration, (NS, Swedish abbreviation), performed in 11 forest sites in the middle of Sweden 8-14 years ago. Since NS recently have become applied, it has never yet been evaluated.

The thick-shelled river mussel (Unio crassus) is a red listed species classified as Endangered (EN) and is also considered within the Habitats Directive. The distribution in Sweden is fragmented and it is mostly occurring in the south eastern parts. We investigated the presence of Unio crassus in a section of the stream Storån, Östergötland County, from Falerum to the inflow into Lake Åkervristen. The environmental parameters investigated were water depth, bottom substrate, shading, water velocity and the slope over the water surface. In this thesis I have focused mainly on water depth and shading, comparing sites with and without mussels.

Successful forest regeneration is a prerequisite for sustainable forest management. Therefore, it is important to prevent browsing damage on the commercially important tree species Scots pine. In this study I have tested a new alternative way to increase the available amount of forage and increase the use of these resources by especially moose. The method is based on a slash treatment at harvest, where the accessibility of slash as forage is increased during final felling or commercial thinning by gathering the slash and putting the Scots pine slash on top of the slash piles. This study has compared the availability of forage, the amount of browsed biomass and the number of fecal pellet groups between conventional and slash treated stands after final felling and commercial thinning in southern Sweden.

Warthogs live under natural conditions in matriarchal groups, bachelor groups and yearling groups. Just like all pig species do warthogs have a complex behaviour repertoire. The semi-wild warthog population at Kichwa Tembo Lodge, outside Masai Mara National Reserve, lives in a fenced area with access to food all over the year and is protected from predators. The aim of this study was to observe the male warthogs? mating behaviour and their hierarchy during the mating season.

The wild boar (Sus scrofa L.) has expanded across Europe and Sweden in the last decades. It is a generalist species which utilizes a variety of habitats, and its presence has been shown to have both positive and negative effects for people and the landscape they are in. The abundance and increase of wild boar has previously been shown to differ between counties in Sweden, but there have been few explanations as to why. In this study, I investigated correlations between the per capita rate of change (r) among wild boar populations in Sweden and a variety of different habitats on the county level. I also investigated if fragmentation per se or in certain habitats could be associated with the wild boar?s per capita rate of change. My results show that fragmentation/diversity per se was not correlated with wild boar r.

Rotavirus causes diarrhea in young mammals all over the world, including infant humans. The diarrhea leads to severe dehydration that can be fatal if left untreated. The dehydration can be treated with fluid therapy and the infection heals itself. Despite the relatively easy treatment half a million children under the age of five dies every year due to diarrhea caused by rotavirus. Rotavirus sorts into the family Reoviridae and is a double-stranded RNA virus with a segmented genome.

Through millennia, humans have shaped the European landscapes. Agriculture, hunting andforestry have influenced virtually every ecosystem on the continent and formed what we todaythink of as the cultural landscape; a mosaic pattern of cropland, fields, pasture and forests. Thepast two centuries, globalization, industrialization and urbanization have come to pose a threatto the existence of these landscapes. European farmlands are now being abandoned at analarming rate, and the associated loss of landscape preservation, biodiversity and ecosystemservices is a concern to the scientific community and public alike.This thesis studies if the implementation of the relatively new conservation strategy rewilding(recreating self-sustaining ecosystems and reintroducing keystone species) can be a part of thesolution to preserve cultural landscapes and biodiversity in Sweden. Through interviewssupplemented with studies of published works, expertise from different fields has beencompiled to provide an overall picture of the capacity of rewildings as conservation method.

In a time of increasing urbanization the human tenure effects on the land has lead to a decrease and fragmentation of areas that are valuable to urban wildlife. These actions have had a detrimental effect on the species and habitats that exist in cities and towns.This paper investigates, through the study of relevant literature and the undertaking of interviews and field visits, the role that biodiversity plays in our society. The current attitude towards urban biodiversity and the responsibility for its promotion within the landscape architect profession has been explored.This paper includes three English case studies and a design proposal investigating how one can work to promote biodiversity on a smaller scale.This paper concludes that urban biodiversity is multi-functional ? being of ecological, social and cultural significance. The landscape architecture profession must be aware of the need to combine a variety of different factors such as economical, social and environmental aspects.