Warmer climate is a driving factor to species expansion northwards. Expansion to new areas can result in escape from natural enemies, resulting in reduced levels of mortality and thereby potentially increasing the rate of expansion. The most important parasitoid species attacking butterfly larvae belong to the families Tachinidae, Ichneumonidae and Braconidae. The aim of this thesis was to investigate parasitism and difference between populations in established area and newly colonized area for the European map butterfly, Araschnia levana, in order to examine if the butterfly has escaped from some natural enemies. In 1982 the first European map butterfly was observed in Sweden and has now established up to middle Småland.

Modern methods for managing pine (Pinus sylvestris) create homogenized forests. This decreases nature?s potential for biodiversity and might threaten species in need of different types of milieu. The main purpose of this study was to investigate how important older pine trees are for biodiversity. In the Hall-Hangvar Reserve in the north-west part of Gotland, insects collected from traps showed that more species were found in old or dead trees compared to younger pine trees.

During the last two hundred years many wetlands and streams in Sweden have been lowered to provide land for agriculture and forestry. Some of the coastal wetlands and streams probably served as spawning sites for certain species of fish in the Baltic Sea, but the present situation is not well known. As standardized methods to monitor fish in running waters are carried out during late summer or autumn, there is a need for methods to sample spring-spawning fish in these streams.The aim of this study was to survey the lower kilometer stretch of Hammerstaån in Stockholm, to investigate the extent to which the stream is used by spring-spawning fish. Furthermore, the study aims to evaluate a new type of survey fishing gill net calledströmöversiktsnät (SÖN). This was done by comparing the catch of fish by SÖN with that of fyke nets.

Plagionotus detritus is a threatend longhorn beetle that only exists at one site in Sweden. It is saproxylic and depending on recently dead coarse oak wood for its larval development. Trees at Djurgården, Stockholm that have been colonized by Plagionotus detritus has been studied to find out the habitat preferences of the species and to see what affects the density of beetles in a tree. The bark of some trees and wood from the breeding project at Nordens Ark has also been studied to find out what affects the species reproductive success. The reproductive success was measured in two ways, the larval mortality and the size of the hatching holes.

The natterjack toad (Bufo calamita) is one of three species of toads living in Sweden. During the last decades declines in population numbers have been detected and are thought to be primarily due to loss of habitat, overgrown breeding ponds and competition from common toad (Bufo bufo) and common frog (Rana temporaria). In 2012 20 ponds in the location of Glommeskallen in Smögen were restored by clearing the ponds from overgrowth. The aim of this study was to investigate if natterjack toads used the restored ponds and if the restoration had made an impact on the natterjack population on the location. Presence of common toad and common frog was recorded, as was the presence of eggs and larvae of any of the three species.

This thesis deal with tick burden on roe deer (Capreolus capreolus) fawns, in relation to age, weight, hind foot length, and as well as to vegetation and habitat on bed sites. Roe deer fawns (N = 25) were captured from May 27 to June 27. Samples of ticks were collected and tick burden were estimated. Of all sampled ticks the nymphs and adults were Ixodes ricinus, while the larvae were not identified. 4.4 % of the sampled ticks were larvae, 55.0 % nymphs, 26.8 % adult females, and 13.8 % adult males.

Many wood living insects are considered threatened by modern forestry due to the reduction in amount of dead wood. During the last decade various methods have been used to enhance the quantity of dead wood in managed forests. However little is known how and if these methods are aiding saproxylic insects. The threatened tenebrionid beetle, Upis ceramboides, is already extinct in southern Sweden. It develops in white rotted dead birch (Betula spp) and requires sun-exposed sites.

The purpose of this paper is to examine what problems cabbage growers have with the Swede Midge. The last few years the Swede Midge, Contarinia nasturtii, has become a larger problem for cabbage growers in several countries in Europe as well as in Sweden. In Canada the problems are so severe that the midge is classified as a quarantine pest and therefore certain rules have to be followed. I have collected facts of the biology, host plants and reproduction of the Swede Midge, as well as the growers experiences and the occurrence of the midge in Canada, Europe and Sweden. The Swede Midge is hard to control because of its short life cycle and the larvae are protected between the heartleaves of the plant. When the larva feeds on the growth point the plant becomes distorted, in some cases several heads develop or none at all. When the midge infests spring rape its flower buds become undeveloped and rosette like.

Francisella tularensis, the causative agent of the zoonotic disease tularaemia, is highly contagious and potentially fatal for a wide range of wildlife species of the northern hemisphere, also humans. Although recognized as a pathogen for over 100 years, much still remains to be elucidated concerning the ecology and transmission of the bacterium, hence this literature overview aims at compiling data regarding the aquatic association and the role of mosquitoes in transmission of Francisella tularensis subspecies holartica, the sole subspecies in Sweden. While a linkage between the bacterium and natural waters stands beyond dispute, there is no consensus in the literature concerning its potential as a reservoir. However, two prevailing theories can be distinguished; one proposes the water association being mammaldependent and thus merely the result of contamination from semi-aquatic mammals living in close vicinity to the water source. The other, quite contrary, suggests mammal-independence and hence that water, possibly in association with protozoa, serves as an environmental reservoir for the bacterium.

Delia flies (Diptera: Anthomyiidae) are economically important pests in several horticultural crops. The control is commonly relying on chemical insecticides, though there are possibilities with biological control from the natural enemies in the field. An important natural enemy is the parasitic wasp, Trybliographa rapae Westwood (Hymenoptera: Figitidae) that lays eggs in the Delia fly larvae. The parasitoid larva and the host larva have a parallel development until the host dies within its puparium and an adult parasitoid emerges. The aim of this thesis was to understand the attraction to host- and food-associated plant volatiles of T. rapae, in order to enhance the effectiveness of the parasitic wasp as a biological control agent.

Twenty-four calves, which had not grazed previously, were divided into four groups. They were subsequently inoculated orally with either E. alabamensis oocysts, O.ostertagi/C. oncophora larvae, or both. One group remained uninfected and was used as a control.

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.

Totally 84 differentially expressed mRNA clones from infective L3 larvae of the parasite Haemonchus contortus, a blood sucking nematode, were analyzed with single strand hybridization assay (SSH). Altogether 79 clones were sequenced, edited, and compared with proteins found via BLAST in GeneBank. The aim was to investigate gene expression and potential protein expression following storage at 5 °C for 32 weeks. mRNA was extracted from fresh and stored L3. The SSH derived products were cloned into E.

The purpose of this study was to investigate how elevated levels of heavy metals affect the faunal species composition, abundance and species-diversity. The bentic macroinvertebrate fauna in the highly polluted lake Tisken was compared with the bentic macroinvertebrate fauna in the unpolluted lake Varpan. Mine wastes account for most of the metal that is discharged into Tisken. The hypotheses was that the heavy metal pollutions in lake Tisken influenced the species composition, abundance and diversity of the macroinvertebrates. Twenty samples were taken in both sites.

The purpose of this paper was to analyze fishbones from the Pitted Ware Culture settlement named Hemmor. in Dalbo, När parish on Gotland. The fishbones are unburnt and derive from one specific culture layer (c:6) in trench one VI:7, and radiocarbon dated to 2600-2300 BC cal.In this paper I wanted to answer these following questions:1. What kind of fish species did they eat in Hemmor?2.