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  • 1.
    Abecasis, David
    et al.
    University of the Algarve, Portugal.
    Steckenreuter, Andre
    University of the Azores, Portugal.
    Reubens, Jan
    Flanders Marine Institute, Belgium.
    Aaestrup, Kim
    DTU, Denmark.
    Alos, Josep
    Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), Spain.
    Badalamenti, Fabio
    CNR-IAMC, Italy.
    Bajona, Lenore
    Dalhousie University, Canada.
    Boylan, Patrick
    Loughs Agency, UK.
    Deneudt, Klaas
    Flanders Marine Institute, Belgium.
    Greenberg, Larry
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Brevé, Niels
    Sportfisserij Nederland, The Netherlands.
    Hernandez, Francisco
    Flanders Marine Institute, Belgium.
    Humphries, Nick
    The Marine Biological Association of the U.K, UK.
    Meyer, Carl
    University of Hawai’i at Mānoa, USA.
    Sims, David
    University of Southampton, UK.
    Thorstad, Eva B.
    Norwegian Institute for Nature Research (NINA), Norway.
    Walker, Alan M.
    Centre for Environment, Fisheries and Aquaculture Science (Cefas), UK.
    Whoriskey, Fred
    Dalhousie University, Canada.
    Alfonso, Pedro
    University of the Azores, Portugal.
    A review of acoustic telemetry in Europe and the need for a regional aquatic telemetry network2018Inngår i: Animal Biotelemetry, ISSN 2050-3385, E-ISSN 2050-3385, Vol. 6, s. 1-7, artikkel-id 12Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Globally, there are a large and growing number of researchers using biotelemetry as a tool to studyaquatic animals. In Europe, this community lacks a formal network structure. The aim of this study is to review the useof acoustic telemetry in Europe and document the contribution of cross-boundary studies and inter-research groupcollaborations. Based on this, we explore the potential benefits and challenges of a network approach to identifyfuture priorities and best practices for aquatic biotelemetry research in Europe.

    Results: Over the past decade, there was an approximately sevenfold increase in the number of acoustic telemetrystudies published on marine and diadromous species in Europe compared to a sixfold increase globally. Over 90%of these studies were conducted on fishes and undertaken in coastal areas, estuaries, or rivers. 75% of these studieswere conducted by researchers based in one of five nations (Norway, UK, France, Portugal, and Spain) and, eventhough 34% were based on collaborations between scientists from several countries, there was only one study withan acoustic receiver array that extended beyond the borders of a single country. In recent years, acoustic telemetryin European waters has evolved from studying behavioural aspects of animals (82.2%), into more holistic approachesaddressing management-related issues (10%), tagging methods and effects (5%), and technology and data analysisdevelopment (2.8%).

    Conclusions: Despite the increasing number of publications and species tracked, there is a prominent lack ofplanned and structured acoustic telemetry collaborations in Europe. A formal pan-European network structure wouldpromote the development of (1) a research platform that could benefit the acoustic telemetry community throughcapacity building, (2) a centralized database, and (3) key deployment sites and studies on priority species requiringresearch in Europe. A network may increase efficiency, expand the scope of research that can be undertaken, promoteEuropean science integration, enhance the opportunities and success of acquiring research funding and, ultimately,foster regional and transatlantic collaborations. It may also help address research priorities such as the large-scalesocietal challenges arising from climate change impacts and assist the EU’s Marine Strategy Framework Directive viaidentification of good environmental status of endangered or commercially important species.

  • 2.
    Adolfsson, Oscar
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Effekter av inkuberingstemperatur hos juvenil atlantlax (Salmo salar L.)2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Rising temperatures, because of climate change, will have major consequences for the world's fish populations, including the Atlantic salmon Salmo salar L. The greatest temperature changes are expected to occur during winter, which will affect S. salar since the eggs are developing during this time of year. Several studies have shown that elevated temperatures during embryogenesis cause morphological changes, in S. Salar, that are shown in later life stages. Some of these studies indicate that eggs incubated at high temperatures should generate parr with deeper bodies. To investigate whether high temperatures during the egg stage cause changes in body shape, parr from normal and high temperature incubated eggs, referred to as as “cold” and “warm” fish, respectively, were examined. A box-truss of euclidean distances between 10 landmarks on the fish body and a discriminant function analysis (DFA) was used to determine which of the distances best discriminated between the two groups. The test showed a significant discrimination between cold and warm parr regarding body shape where cold parr had greater heads and warm parr were deeper over the tail region and showed greater distances between the pelvic fin and the front attachment of the anal fin. 67,3 % of all parr where correctly classified by the test. These results support those notions that indicates that the incubation temperature is important for the morphological development of S. salar although it does not support the hypothesis.

  • 3. Affonso, Igor de Paiva
    et al.
    Karling, Leticia Cucolo
    Takemoto, Ricardo Massato
    Gomes, Luiz Carlos
    Nilsson, Per Anders
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013). Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Light-induced eye-fluke behavior enhances parasite life cycle2017Inngår i: Frontiers in Ecology and the Environment, ISSN 1540-9295, E-ISSN 1540-9309, Vol. 15, nr 6, s. 340-341Artikkel i tidsskrift (Fagfellevurdert)
  • 4.
    Ahlgren, Johan
    et al.
    Lund Univ, Dept Biol Aquat Ecol, S-22362 Lund, Sweden..
    Chapman, Ben B.
    Lund Univ, Dept Biol Aquat Ecol, S-22362 Lund, Sweden.;Univ Nottingham, Sch Life Sci, Nottingham NG7 2RD, England..
    Nilsson, Anders P.
    Bronmark, Christer
    Lund Univ, Dept Biol Aquat Ecol, S-22362 Lund, Sweden..
    Individual boldness is linked to protective shell shape in aquatic snails2015Inngår i: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, nr 4, artikkel-id UNSP 20150029Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The existence of consistent individual differences in behaviour ('animal personality') has been well documented in recent years. However, how such individual variation in behaviour is maintained over evolutionary time is an ongoing conundrum. A well-studied axis of animal personality is individual variation along a bold-shy continuum, where individuals differ consistently in their propensity to take risks. A predation-risk cost to boldness is often assumed, but also that the reproductive benefits associated with boldness lead to equivalent fitness outcomes between bold and shy individuals over a lifetime. However, an alternative or complementary explanation may be that bold individuals phenotypically compensate for their risky lifestyle to reduce predation costs, for instance by investing in more pronounced morphological defences. Here, we investigate the 'phenotypic compensation' hypothesis, i.e. that bold individuals exhibit more pronounced anti-predator defences than shy individuals, by relating shell shape in the aquatic snail Radix balthica to an index of individual boldness. Our analyses find a strong relationship between risk-taking propensity and shell shape in this species, with bolder individuals exhibiting a more defended shell shape than shy individuals. We suggest that this supports the 'phenotypic compensation' hypothesis and sheds light on a previously poorly studied mechanism to promote the maintenance of personality variation among animals.

  • 5.
    Ahlin, Julia
    Karlstads universitet, Fakulteten för humaniora och samhällsvetenskap (from 2013), Institutionen för pedagogiska studier (from 2013).
    Handhygien i förskolan: Pedagoger och barns uppfattningar av handhygien och dess roll i förskolan2018Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    This study is about preschool teachers and children perceptions about hand hygiene in preschool. It also focusses on preschool teachers’ way of working when it comes to hand hygiene against children. The purpose with this study was to illuminate preschool teachers’ attitudes and working methods with hand hygiene in the preschool and how children reason about hand hygiene. Seven preschool teachers and twelve children from two different preschool participated in the study. The children were interviewed in pairs and the preschool teachers were interviewed individually. It can be read in the results that the preschool teachers think that the children know why they wash their hands and the children agree about that. All seven preschool teachers also indicate that they talk with children about hand hygiene and why it is important. The children do not think that the preschool teachers talk to them about hand hygiene. However, the children do show knowledge about why they should wash their hands and also explains what would happen if they did not do it. Maybe the preschool teachers and the children have different point of view of what ”talking” is in this context when their answers doesn’t match. The preschool teachers and children have a similar perception when it comes to what hand hygiene routines they have and what they use when they wash their hands.

  • 6.
    Al- Robeyi, Zainab
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Att uppleva naturen med alla sina sinnen: Hur undersöker och upplever förskolebarnen naturen?2013Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    This project discusses various aspects of children's way to explore nature with their senses. Therefore I conducted a study in two preschools, one nature-oriented and another preschool. This study was carriedout usien the three metods, interviews, observations and surveys. Interview four children from each preschool, observations of each group outdoors during four different occasions and question forms to teachers.

     

    The result of the study showed that both teachers and children have a great interest in being outdoors in nature, but it is not always possible to take out all children's groups. The reason is large groups and inadequate staff. When you are out in the forest according to teachers, it is important to be attentive, present, and meet the children’s interests. They need to be stimulated with questions and inspire them about what is happening and what might happen in nature plus take natural materials as help in the creative activities of the preschool.

     

    Keywords: Biology, children's perceptions, exploring, outdoor environment

  • 7.
    Almgren Damberg, Ingrid
    Karlstads universitet, Fakulteten för humaniora och samhällsvetenskap (from 2013), Institutionen för pedagogiska studier.
    "Nyss så träffa jag en krokodil, som körde runt i en bil": Små barns kompetenser i ämnet biologi2015Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    The purpose of the study is to show young children's competences in the subject of biology. I hope that my work will lead to that the subject of biology is used more often in the preschool context. In my work I have had an intra-active theory as a base. I have searched for what children are interested in on the subject of biology. Here, I can conclude that animals and plants are major interests for the children. Furthermore, I wanted to explore the ways in which children's knowledge became visible. For the most part, small children (along with educators) use animism and anthropomorphism, however, this is often interwoven with facts. I also wanted to know whether there were factors that contributed to children's learning in biology. It became clear that factors such as outdoor stay and live animals and plants contributed to a fact-based learning in biology. In contrast, factors such as indoor stay and toys were important factors for an animistic and anthropomorphic learning in biology. Educators also have a crucial role in children's learning in biology. Through an intra-active approach, I note that both the factual events of biology and animism and anthropomorphism contribute to the child's creation of knowledge in biology.

  • 8.
    Alvsenius Fransson, Åse
    Karlstads universitet.
    Behövs det speciella anordningar för att bedriva utomhuspedagogik?2008Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I mitt arbete har jag genom observationer och intervjuer undersökt om skolskogen och den vanliga skogen är bra komplement när det handlar om utomhuspedagik. De flesta av förskolorna i kommunen har en skolskog att tillgå och har man inte det växer skogen nästan inpå knutarna. De pedagoger som blivit intervjuade anser att det är viktigt att lära barnen tidigtvad man får och inte får göra i naturen och att skolskogen då är ett bättre alternativ. En skolskog skiljer sig från en vanlig skog genom att det finns färdiga vindskydd, eldstäder och hinderbanor. Genom avtal med markägaren har förskolan eller skolan fått tillstånd att tänja lite på allemansrättens gränser Dessutom är det bra för både barn och pedagoger att spendera mycket tid ute i naturen därför att den friska luften gör att det blir färre sjukdomar. I läroplanen står det att förskolan skall lägga stor vikt på natur och miljö, samt att vi ska värna om barnens hälsa. Den litteratur jag använt mig av i arbetet handlar om hur viktigt det är att arbeta med utomhuspedagogik i förskolan och att skolskogen och skogen är mycket bra att vistas i. Litteraturen tar även upp hur viktigt det är att pedagogen har bra kunskap om naturen för att vistelsen ska bli så bra och lärorik som möjligt för barnen.

  • 9.
    Andersson, Anders
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper.
    Catch and effort from a recreational trolling fishery in a large lake2016Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Over recent decades recreational fisheries have grown substantially throughout the world. Despite this increase, catches from recreational fisheries have often been ignored in fisheries management, although this is now being remedied. Monitoring recreational fisheries can be expensive, and the primary means used for monitoring is angler (creel) surveys, typically funded from sales of fishing licences. The studies presented in this thesis examine different approaches to monitoring recreational trolling fisheries’ catch and effort, where fishing licenses are not required and there are no reporting requirements. I present results from a complemented roving/mail-in survey undertaken during 2013-2014 to estimate recreational effort and catch of Atlantic salmon (Salmo salar) and brown trout (S. trutta) in the largest lake in the European Union, Lake Vänern, Sweden. I also evaluate different angler catch reporting methods (mail-in, tournament reports and face-to-face interviews) and compare catch rates within and among spring and fall fishing periods. In addition, mail-in survey data are examined for recall bias.

     

    I estimate that 28.7 tonnes of salmon and trout combined were harvested by the recreational trolling fishery in 2014, more than the commercial and subsistence fisheries combined. Seasonal differences in both recreational effort and catch were observed. Effort, in boat hours, was significantly higher in spring than in fall. Catch rates of trout were higher in fall than in spring, but there were no seasonal differences in catches of salmon. Harvest per boat day did not differ significantly among catch reporting methods, indicating that all three methods could be useful for managers interested in harvest rates. In contrast, total and released catch per boat day differed among reporting methods, with tournament anglers catching more fish in total. Finally, there was little evidence for recall bias in mail-in surveys, indicating that mail-in surveys are useful for collecting unbiased catch data. My study is the most comprehensive angler survey to date for Lake Vänern, and my results should be of immediate use to local fisheries managers and should also be of interest to researchers and managers interested in estimating catch and effort for fisheries at large spatial scales.

  • 10.
    Andersson, Anders
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Bergman, Eva
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Greenberg, Larry
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Piccolo, John
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Comparing mail-in, interview and tournament catch rates for a recreational salmonid fisheryManuskript (preprint) (Annet vitenskapelig)
  • 11.
    Andersson, Anders
    et al.
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Greenberg, Larry
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Bergman, Eva
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Su, Zhenming
    Andersson, Magnus
    Piccolo, John
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Estimating effort and catch of a recreational trolling fishery in one of Europe’s largest lakesManuskript (preprint) (Annet vitenskapelig)
  • 12.
    Andersson, Fredrika
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Barns tankar om den egna kroppen!: Vad vet fyraåringar och sexåringar om sin kropp!2009Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Mitt syfte med detta arbete var att ta reda på vad barn har för uppfattning om människokroppen när de är fyra och sex år gamla. Sex barn har blivit intervjuade genom kvalitativa intervjuer. Barnens uppfattning om kroppen är olika beroende på deras ålder. Sexåringen har större kunskap om kroppen än vad fyra åringar har. Barnens spontana uppfattning om vad som finns i vår kropp var att vi har; hjärta, hjärna, blod, hjärnceller, muskler och skelett.

  • 13.
    Andersson, Frida
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Vikten av utevistelse inom förskolan: En studie av pedagogers tankar och syften med utevistelse2008Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I min undersökning har fem pedagoger genom strukturerade intervjuer fått svara på frågor om utevistelsen på förskolan. Syftet var att ta reda på vad pedagogerna själva hade för tankar och syften bakom utevistelsen, samt hur de arbetade med detta. Frågorna gällde både vistelsen i den planerade miljön på gården och i naturen.

    Pedagogerna fann mestadels fördelar med utevistelse på förskolan. Några av fördelarna som nämndes var god motorikträning och social träning. Sedan belystes även vikten av ”frisk luft” och att pedagogerna upplevde barnen som piggare om de vistades utomhus emellanåt.

    Minst en gång om dagen går de ut med barnen på gården och de flesta försöker komma iväg till skogen en gång i veckan. En nackdel kan vara avbrott under leken inomhus för att man ska gå ut.

    Pedagogerna framhåller i sina syften att de vill förmedla kunskap om naturen på ett lekfullt sätt för att stimulera barnens nyfikenhet genom utevistelsen.

    Nyckelord: Lekfullt, nyfikenhet, pedagogers syften, utevistelse

  • 14.
    Andersson, Jan-Olov
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    A GIS-based landscape analysis of dissolved organic carbon in boreal headwater streams2009Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    In boreal catchments, stream water chemistry is influenced and controlled by several landscape factors. The influence of spatially distributed variables is in turn dependent on the hydrological scale. Headwater streams have larger variability of water chemistry, and thus together represent a large biodiversity, and therefore need to be monitored in official environmental assessments. One objective of this study was, using Geographical Information Systems (GIS), to analyse co-variation between landscape variables and water chemistry and to determine which of the landscape variables have a major influence on the concentration of dissolved organic carbon (DOC) in headwater streams. Another objective was to find a simple method for predicting sources of DOC, using official map data and publically available GIS applications.

    Totally 85 headwater catchments (0.1-4 km2) in the county of Värmland, western south Sweden, were used in the study. Water chemistry was analysed for water sampled at low, medium and high flows, and landscape variables were extracted from official map data sources: topographic maps, a digital elevation model (DEM, 50 m grid), and vegetation data. Statistical analyses showed that topography (mean slope and mean topographic wetness index (TWI)) and wetland cover often correlated well with DOC in headwater catchments. Official map data could satisfactorily extract landscape variables (mean slope, mean TWI) that were useful in predicting stream water chemistry (DOC).

    A high-resolution elevation model, which was generated by interpolation of photogrammetric data, was used to calculate and evaluate two different wetness indices and their ability to predict the occurrence of wetlands in six catchments of different sizes and topography. The SAGA (System for Automated Geoscientific Analyses) wetness index (SWI) gave substantially better results than the TWI. The effects of resolution of DEMs on calculations of the SWI were investigated using 5, 10, 25 and 50 m grids. The results showed that SWI values increased with increasing cell size. The near linear increment of mean values for resolutions 10-50 m suggests a independence of terrain type and catchment size, which supported previous findings that indicated that mean slope and mean wetness index calculated from coarse elevation models may be used for prediction of DOC in headwater streams.

     

  • 15.
    Andersson, Jan-Olov
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    DEM resolution effects on SAGA wetness index in boreal forested catchmentsManuskript (Annet vitenskapelig)
  • 16.
    Andersson, Jan-Olov
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Nyberg, Lars
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Centrum för klimat och säkerhet.
    Spatial variation of wetlands and flux of dissolved organic carbon in boreal headwater streams2008Inngår i: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, nr 22, s. 1965-1975Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to investigate the relation between water chemistry and functional landscape elements, spatial data sets of characteristics for 68 small (0·2–1·5 km2) boreal forest catchments in western central Sweden were analysed in a geographical information system (GIS). The geographic data used were extracted from official topographic maps. Water sampled four times at different flow situations was analysed chemically. This paper focuses on one phenomenon that has an important influence on headwater quality in boreal, coniferous forest streams: generation and export of dissolved organic carbon (DOC). It is known that wetland cover (bogs and fens) in the catchment is a major source of DOC. In this study, a comparison was made between a large number of headwater catchments with varying spatial locations and areas of wetlands. How this variation, together with a number of other spatial variables, influences the DOC flux in the streamwater was analysed by statistical methods. There were significant, but not strong, correlations between the total percentages of wetland area and DOC flux measured at a medium flow situation, but not at high flow. Neither were there any significant correlations between the percentage of wetland area connected to streams, nor the percentage of wetland area within a zone 50 m from the stream and the DOC flux. There were, however, correlations between catchment mean slope and the DOC flux in all but one flow situations. This study showed that, considering geographical data retrieved from official sources, the topography of a catchment better explains the variation in DOC flux than the percentage and locations of distinct wetland areas. This emphasizes the need for high-resolution elevation models accurate enough to reveal the sources of DOC found in headwater streams.

  • 17.
    Andersson, Jan-Olov
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Nyberg, Lars
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Centrum för klimat och säkerhet.
    Using official map data on topography, wetlands and vegetation cover for prediction of stream water chemistry in boreal headwater catchments2009Inngår i: Hydrology and Earth System Sciences, ISSN 1027-5606, E-ISSN 1607-7938, Vol. 13, s. 537-549Artikkel i tidsskrift (Fagfellevurdert)
  • 18.
    Andersson, Jan-Olov
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Nyberg, Lars
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Centrum för klimat och säkerhet.
    Wetness indices as predictors of boreal wetlandsManuskript (Annet vitenskapelig)
  • 19.
    Andersson, Jeanette
    Karlstads universitet.
    Påverkan av jakttryck, habitatförlust och populationsstorlek på jaguar (Panthera onca) i Tapajós - Arapiuns Extractive Reservat i centrala Amazonas2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The jaguar is endangered due to hunting and deforestation of rainforests, which in turn reduces the jaguar’s prey. This report is based on a population in the Tapajós - Arapiuns Extractive Reserve in central Amazonia and how hunting pressure, the distribution of sexes killed by hunting, the loss of habitat and population size affect the population during the next 100 years. With the help of previous studies on the hunting pressure and information about jaguar biology in the Tapajos, different simulation models were conducted to gain an appreciation of how the jaguar was affected. A total of thirteen scenarios was made. In the scenarios without hunting and habitat loss, which is not very likely to occur.

    I found that the jaguar has good chances of survival after 100 years. Scenarios with low hunting pressure, with the removal of 3 females and 9 males per year indicated that the population declined but still had a good chance of survival. Survival was less likely when hunting pressure increased to 5 females and 14 males. If habitat loss was added to the high hunting pressure, the jaguars went extinct even faster. Scenarios with a habitat loss of 0.24% or 0.71% represented a low risk of extinction in 100 years, but if hunting was added, the risk of extinction increased dramatically. In scenarios with a smaller population size, with different hunting pressure and habitat loss, the populations were very sensitive to change. In the worst case scenario, with hunting higher on females than males, there were serious negative impacts on the population, which is likely to go extinct very quickly.

  • 20.
    Andersson, Jessica
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Barns beteenden i naturen2007Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    This study is based on qualitative interviews with five-year-old children from a nursery school and two teachers with great experience. The purpose with the interviews is to find out what knowledge these children have about the Right of Common and what the teachers think they need to find this knowledge.

    The children didn't know what the word Right of Common stands for but when they got more concrete alternatives they had good experiences. The two teachers had different opinions about what is the most important concerning the stays in the nature. Exercise meant a lot for one teacher. To have fun and to use all your senses were more important for the other one. To give the wooded strolls new permanent experiences it is recommended to use your imagination.

    Key words: The Right of Common, science, process of learning

  • 21.
    Andersson, Lena
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper (from 2013).
    Flodpärlmusslans (Margaritifera margaritifera) påverkan på öringens (Salmo trutta) tillväxt, konditionsfaktor och habitatval.2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The freshwater mussel family Unionoida lives a complex life with its host animals and the freshwater mussel family’s existence is threatened worldwide. One of these species, the pearl mussel (Margaritifera margaritifera), is a “responsibility species” for Scandinavia and a lot of work is ongoing to save the species. In Scandinavia there are still existing populations, but in many waters recruitment of juvenile mussels is completely lacking or insufficient. To support recruitment and also reintroduce the mussel into suitable watercourses, more knowledge about its complex life cycle and how it affects its host brown trout (Salmo trutta), is required. Attempts have been made to introduce gravid mussels or already infected trout in order to try to rejuvenate or to reintroduce mussels in some rivers. In this study, 293 trout individuals were captured from three watercourses in western Sweden with no or inadequate recruitment of juvenile pearl mussels. The brown trout were treated with mussel infection by being kept in containers with the presence of gravid mussels and compared to a control group where no mussels were present. Growth, condition factor and habitat selection were investigated and checked after treatment by scanning the trout with a mobile scanner and recaptured for control. The analyzes showed a significantly lower growth on those trout treated with mussel infection during the time they were stored in the containers. After a month in freedom in the streams, there was no differences in growth or condition factor. Habitat choice studies showed that trout with a higher degree of infection chose calmer water with a bottom layer of finer sediment. The study showed that this method could be a simple way of increasing the reproduction success of pearl mussel. The method requires relatively little work effort and small disturbance to host fish or the aquatic environment.

  • 22. Andersson, Lena U
    Betydelsen av bark pH på lövträd för fyra epifytiska mossor.2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    Several species of  epiphytic bryophytes in Sweden are endangered because of habitat loss, which in turn is caused by intensified forestry and changes in the cultural landscape. Several species of common deciduous trees have also been threatened by diseases, which has reduced their numbers. A couple of our environmental goals in Sweden address forestry and the conservation of biodiversity. Since it is known that the red listed species are more common on trees with a higher bark pH  I have chosen to compare four common mosses; two that are common in special environments such as tree-lined avenues and parks and two that are common on most trees in western Sweden. This study investigated the difference of bark pH for Leucodon sciuroides, Homalothecium sericeum, Hypnum cupressiforme and Ulota crispa on different host tree species in three different study areas. The hypothesis was that preferences for bark pH differ significantly between the different mosses. It was found that Leucodon sciuroides and  Homalothecium sericeum  were more common on trees with a higher bark pH while Hypnum cupressiforme and Ulota crispa grew on tree bark with a lower pH. Furthermore it was found that both Hypnum cupressiforme and Ulota crispa could also be found on tree bark with a higher pH. There was also a difference in terms of tree species. The avenue trees had the most species, especially the ash tree.

  • 23.
    Andersson, Madelen
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Naturvårdsbränningens effekter på botten- och fältskiktsvegetation2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Forest fires are an important part of the boreal forest ecosystem but have become very reduced in Sweden over the past 100 years. To recreate this feature in nature, prescribed forest fire has become a management method used to promote biodiversity. The purpose of this study was to investigate the effects of prescribed forest fire on the ground and field layer vegetation in terms of vegetation structure, species composition, coverage ratio, biomass and soil pH. The study was conducted in the Brännan Nature Reserve where prescribed forest fires have been implemented on several occasions during the past 21 years, which also made it possible to compare several areas and investigate effects over time. Four sub-areas were studied, three previously fire-affected areas and one control area. The result shows that prescribed forest fires influence the ground and field layer vegetation, and there were significant differences between the areas. The vegetation structure changed, and new conditions were created for subsequent successional processes. The effective number of species decreased after the fire but subsequently increased over time. The percentage of vegetation cover showed the same result with a rapid re-establishment rate, especially during the 6 following years. Biomass production reached the highest value 21 years after the fire, but showed a declining trend compared to the control area. There was no significant difference regarding soil pH, which was expected. There are many factors that may affect the short- and long-term effects of prescribed forest fires, such as fire intensity and the soil depth reached by the fire, but despite variations among the areas, some trends were found.

  • 24.
    Andersson, Magdalena
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Utvärdering av rörelsemönster hos öring (Salmo trutta) utifrån otolitmikrokemi2014Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The classic view of trout (Salmo trutta) life history is that trout begins its life in freshwater, migrates to the ocean after about 1-4 years and then returns to freshwater to spawn. As trout fry have been caught at the mouth of the River Emån, near the Baltic Sea, researchers have speculated that some trout emigrate during their first year of life. The purpose of this study was to describe the variation in the length of time trout reside in freshwater before they migrate to the ocean for the first time. Another purpose was to investigate whether it was possible to discern where and how long the fish spent in freshwater and saltwater during different parts of their lives. Between 2007 and 2009, 23 adult trout were captured in the River Emån in southeastern Sweden. From each fish, a microchemical analysis of the sagitta otolith was conducted. The analysis focused on measuring the ratio of strontium:calcium from the center of the otolith to its outer edge at 6μm intervals. Based on this analysis, I found that 26% of the trout in the population emigrated to sea before they had reached the age of one. The largest proportion (48%) of trout emigrated between 1 to 2 years of age. The results of my study indicated that there was a significant correlation between age and the number of times that the fish remained in freshwater. I also analyzed the ratio of zinc:calcium and manganese:calcium. The analysis of zinc showed annual fluctuations, including a high value during the fish's first year and a seasonal pattern, with higher values of Zn:Ca in spring and summer. My results also showed some variation of the trace element manganese, half of the fish showed a peak in their first year. The results of this study indicate that by analyzing the concentrations of trace elements in otoliths one can describe individual variation in brown trout movement patterns and life history.

  • 25.
    Andersson, Maria
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Miljö- och naturarbete i förskolan: en studie om hur pedagoger genomför miljö- och naturarbetet i förskolan2013Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Syftet med denna undersökning var att undersöka och beskriva hur arbetet med miljö och natur kan genomföras i förskolan. Undersökningen bygger på kvalitativa semistrukturerade intervjuer med nio stycken pedagoger från fem olika förskolor, i en kommun i Västsverige. Resultatet av undersökningen visar att det finns många olika sätt att arbeta med miljö och natur i förskolan, såväl praktiska som teoretiska. Att arbeta med återvinning, kompostering och samtala om bevarandet av resurser, var några av de aktiviteter som undersökningens pedagoger brukade göra. Det framkom också i undersökningen att det i arbetet med miljö- och natur finns vissa hinder som t.ex. personalbrist och pedagogers intressen.

  • 26.
    Andersson, Sandra
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    The effects of artificial illumination on invertebrate drift2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 27.
    Andersson, Örjan
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Hur personlighetstyperna modig eller skygg hos oval dammsnäcka (Radix balthica) påverkas av närvaro eller frånvaro av prederande fisk2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
  • 28. Armstrong, Janet L.
    et al.
    Myers, Katherine W.
    Beauchamp, David A.
    Davis, Nancy D.
    Walker, Robert V.
    Boldt, Jennifer L.
    Piccolo, John
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Haldorson, Lewis J.
    Moss, Jamal H.
    Interannual and Spatial Feeding Patterns of Hatchery and Wild Juvenile Pink Salmon in the Gulf of Alaska in Years of Low and High Survival2008Inngår i: Transactions of the American Fisheries Society 2008; 137: 1299-1316Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To improve understanding of the mechanisms affecting growth and survival, we evaluated the summer diets and feeding patterns (prey composition, energy density, and stomach fullness) of hatchery and wild juvenile pink salmon Oncorhynchus gorbuscha in Prince William Sound (PWS) and the northern coastal Gulf of Alaska (CGOA). Our study (19992004) included 2 years of low (3%), mid (5%), and high (89%) survival of PWS hatchery pink salmon. Because variations in diet should affect growth and ultimately survival, we expected that the variations in diet, growth, and survival would be correlated. During August in the CGOA, pteropod-dominated diets and higher gut fullness corresponded to high survival (59%), and copepod-dominated diets and lower gut fullness corresponded to low survival (3%). Within years, no significant differences were found in diet composition or gut fullness between hatchery and wild fish or among the four PWS hatchery stocks. Diets varied by water mass (habitat) as juveniles moved from PWS to more saline habitats in the CGOA. In July, when juveniles were most abundant in PWS, their diets were dominated by pteropods and hyperiid amphipods. The diets of fish that moved to inner-shelf (i.e., the least-saline) habitat in the CGOA in July were dominated by larvaceans in low-survival years and pteropods in high-survival years. Diet quality was higher in CGOA habitats than in PWS in July. In August, fish moved to the more productive, more saline water masses in the CGOA, where large copepods and pteropods were dominant prey and diet quality was better than in PWS. Our results indicate that spatial variation in the diets of juvenile pink salmon in July and the timing of migration to the CGOA play a critical role in marine growth and survival

  • 29. Aroua, S.
    et al.
    Rousseau, K.
    Schmitz, Monika
    Chang, C.F.
    Elie, P.
    Dufour, S.
    The Gonadoliberin(s)-gonadotropin(s) axis in the eel: expression and regulation under induced maturation and sex steroid feedbacks2007Konferansepaper (Fagfellevurdert)
  • 30.
    Arvidsson, Björn
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Flodpärlmussla - vad behöver vi göra för att rädda arten?2006Rapport (Fagfellevurdert)
  • 31.
    Arvidsson, Björn
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Värmländsk nartur - värd att skydda och vårda2007Kapittel i bok, del av antologi (Fagfellevurdert)
  • 32.
    Arvidsson, Björn
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Hultman, Jens
    Österling, Martin
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Öringtäthet och rekrytering hos flodpärlmussla2006Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 33.
    Arvidsson, Björn
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Karlsson, Jens
    Flodpärlmusslan - skogsbäckarnas aristokrat2004Kapittel i bok, del av antologi (Fagfellevurdert)
  • 34.
    Arvidsson, Björn
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Karlsson, Jens
    Recruitment in populations of freshwater pearl mussel (Margritifera margaritifera) in relation to population size and host density2004Konferansepaper (Fagfellevurdert)
  • 35.
    Arvidsson, Björn
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Karlsson, Svante
    Mer värld i Värmland och mer Värmland i världen2007Kapittel i bok, del av antologi (Fagfellevurdert)
  • 36.
    Arvidsson, Björn L
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Karlsson, Jens
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Österling, Martin E
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Recruitment of the threatened mussel Margaritifera margaritifera in relation to mussel population size, mussel density and host density2012Inngår i: Aquatic conservation, ISSN 1052-7613, E-ISSN 1099-0755, Vol. 22, s. 526-532Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Anthropogenic, abiotic factors are considered main causes of recruitment failure of unionid mussels, including the freshwater pearl mussel (Margaritifera margaritifera). In this large-scale investigation, we instead examined the relationship between biotic factors and mussel recruitment.

    Juvenile mussel density was positively related to both mussel population size and density of which the last appeared to be a more accurate measure of recruitment.Host fish density of young-of-the-year and older brown trout (Salmo trutta) were positively related to recruitment. Moreover, the mean density of both age classes of fish, when grouped into density classes was positively related to juvenile mussel density, an effect that decreased at trout densities above 10 trout 100 m-2.There was a higher relative importance of mussel population size and density than trout density to recruitment.To increase recruitment of juvenile mussels, managers may apply measures that increase mussel density, and trout density up to about 10 trout 100 m-2 in connection to mussel beds. Mussel beds may also be managed and one possible measure within small and sparse mussel populations may be to concentrate the remaining mussels to areas where trout density is high. Likewise, young-of-the-year trout may also be moved to areas of high mussel density, as young trout individuals are relatively resident during their first year. This may increase mussel larval infection rates and mussel recruitment.

  • 37.
    Arvidsson, Björn
    et al.
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Söderberg, Håkan
    Flodpärlmussla - vad behöver vi göra för att rädda arten?: En workshop på Karlstads universitet2006Rapport (Annet vitenskapelig)
    Abstract [sv]

    Flodpärlmusslans situation i Sverige är bekymmersam, och i en stor del av de återstående populationerna sker ingen nyrekrytering av små musslor. För att belysa kunskapsläget om flodpärlmusslans situation och för att diskutera olika åtgärdsmöjligheter genomfördes i november 2005 en work shop vid Karlstads universitet med deltagande av naturvårdare från olika myndigheter och forskare. Vid mötet presenterades aktuell forskning i Skandinavien och olika uppföljningar som sker i olika myndigheters regi. Mötet bekostades av länsstyrelsen i Västernorrland, som fått ett nationellt ansvar att ta fram ett åtgärdsprogram för arten. I denna sammanställning redovisas en del av de föredrag och diskussioner som förekom vid mötet.

  • 38.
    Augustsson, Evelina
    Karlstads universitet.
    Seasonal variability in group size of harbor seals (Phoca vitulina) hauled out on glacial ice in Johns Hopkins Inlet, Glacier Bay National Park, Alaska2010Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Individuals are believed to benefit in various ways from living in groups. Some species aggregate to increase foraging efficiency and others for social benefits. Why pinnipeds rest in groups is yet not fully understood, but the most common ecological explanation is the benefit of enhanced predator detection. An alternative explanation for grouping, however, is limitation of resting sites, which might force individuals to aggregate on whatever sites are available, despite increased competition for food or mates. My study is focused on group size of harbor seals (Phoca vitulina) hauled out on glacial-ice sites in Glacier Bay National Park (GBNP), southeastern Alaska. Previous studies have focused on group size on terrestrial haul-out sites, and to date there have been few studies of group size on ice haul-out sites. In GBNP, peak numbers of harbor seals haul out during the pupping season (June) and the molting season (August). During the breeding season, glacial-ice haul-out sites are used primarily by females and pups, and during the molting season by molting seals. Because seals may group as an anti-predator strategy, I hypothesized that group size would differ between seasons, with smaller groups of mainly mothers and pups during June, and larger-sized groups during August. The aim of this study was to quantify seasonal differences in the group size of harbor seals hauled-out on glacial ice in Johns Hopkins Inlet (JHI), GBNP, southeastern Alaska, and in addition, map and evaluate the large-scale (inlet-level) spatial distribution of seals for both seasons. I used digital aerial survey photographs to map seal distributions. Four replicate aerial surveys were conducted in JHI during both June and August, 2007. Digital images were georeferenced and imported into ArcGIS 9.3 where the location of each seal was digitized, and group size calculated. To assess within- and between-season differences in spatial distribution of hauled-out seals, the location of each seal for each survey was plotted in ArcGIS, and compared to a visual assessment of ice coverage. My results show that harbor seals in JHI tend to haul out as single individuals during both seasons, with the exception of nursing mothers with pups in June, and a few larger-sized groups in August. There was no significant difference in group size between seasons. Group size during June varied very little, with almost all seals being either single or in mother-pup pairs. Group size varied more during August, and although most seals hauled out alone, there were a few larger-sized groups during each survey. The relative lack of grouping behavior is contrary to previous research, and it suggests that predation pressure on seals within JHI may be lower than at other sites. The greater frequency of larger-sized groups in August appeared to be related to reduced availability of glacial-ice haul-out sites. Long-term reduction in the availability of glacial-ice haul-out sites in JHI, therefore, might lead to shifts in haul-out behavior of harbor seals, with more seals being forced to haul out in larger groups.

  • 39. Aurora, S.
    et al.
    LeBelle, N.
    Schmitz, Monika
    Dufours, S.
    In vitro regulation by activinB and IGF-I of gonadotropin expression in European eel, Anguilla anguilla2007Konferansepaper (Fagfellevurdert)
  • 40. Aurora, S.
    et al.
    Schmitz, Monika
    Weltzin, F.A.
    Baloche, S.
    LeBelle, N.
    Rousseau, K.
    Dufours, S.
    Differential expression of LHbeta and FSHbeta in European eel, Anguilla anguilla2006Konferansepaper (Fagfellevurdert)
  • 41.
    Axelsson, Tomas
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    Kantzonsvegetationens inverkan på dieten hos öring (Salmo trutta) i en skogsbäck2008Independent thesis Basic level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Effekterna på öringens (Salmo trutta) diet till följd av en avverkning av kantzonsvegetationen har undersökts i ett fältexperiment, där två av de potentiella effekterna av en skogsavverkning simulerades. Fokus låg på de två faktorerna ökad ljusinstrålning och minskat nedfall av terrestra evertebrater. Ökad ljusinstrålning har simulerats med hjälp av montage av lysrör och nedfall av terrestra evertebrater med hjälp av plasttält. Frågeställningarna rör andelen terrester föda i olika behandlingar och årstider, dietskillnader mellan äldre och yngre öringindivider, skillnader i mängden akvatisk föda vid ökad ljusinstrålning samt en taxonomisk översikt av dietens sammansättning. Signifikanta skillnader mellan behandlingarna fanns, där individerna i kontrollbehandlingen åt signifikant mer terrester föda än individer i tältbehandlingen och den kombinerade tält- och ljusbehandlingen. Signifikanta skillnader fanns även mellan provtagningstillfällena där en högre andel terrester föda återfinns senare på säsongen. Inga signifikanta skillnader fanns med avseende på andelen terrester föda mellan äldre och yngre individer, ej heller mellan mängd akvatisk föda mellan de olika behandlingarna. Den akvatiska födan var mer varierad och divers än den terrestra, och daggmaskar (Lumbriculidae) var en mycket vanlig födopartikel.

  • 42.
    Backius, Helena
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    Förändring av kärlväxters artsammansättning vid återupptagen hävd i skogligt avgränsade ängs- och hagmarker2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I det äldre jordbrukslandskapet finns en biologisk mångfald som man bl.a. försöker bevara genom att via EU:s miljöstöd stimulera lantbrukare att hävda betesmarker och slåtterängar med gammaldags metoder. Men är åtgärderna effektiva och uppfyller de sitt ändamål? Syftet med denna studie var att återinventera 10 stycken provytor från 2002 på gården Brofallet, för att se hur artsammansättningen hos kärlväxter hade påverkats av nio säsongers återupptagen hävd. Gården ligger helt omgiven av skog, isolerad från annan jordbruksmark. Ingen signifikant generell förändring kunde noteras hos hävdgynnade kärlväxtarter. Kvalitativa observationer kunde däremot visa en ökning av vissa hävdgynnade arter. Slutsatsen är att de femåriga åtaganden som lantbrukare gör för att få miljöstöden inte är tillräckliga sett till den totala mångfalden av kärlväxtarter på en gård som Brofallet, men att förändringar däremot kan tänkas ske snabbare på andra nivåer i ekosystemet. I studien diskuteras att även miljöåtgärderna och dokumentationen borde präglas av mångfald, där det småskaliga extensiva jordbruket kan visa sig vara viktigt i det totala strävandet efter ett hållbart samhälle både när det gäller att utnyttja extensiva marker för livsmedelproduktion och för att behålla biodiversiteten på landskapsnivå.

  • 43.
    Bains, Sandra
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Flodpärlmusslans (Margaritifera margaritifera) påverkan på öringens (Salmo trutta) tillväxt och rörelsemönster2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Flervärdsparasiter är kända för att påverka en rad egenskaper såsom morfologi, fysiologi och beteende hos sin värd. Envärdsparasiter såsom flodpärlmussla (Margaritifera margaritifera) lever som larver inkapslade i gälarna på öring (Salmo trutta), men påverkar troligtvis inte sin värd i samma utsträckning som flervärdsparasiter. Detta eftersom de är beroende av värdens överlevnad. Dock har negativa effekterna av envärdsparasiter observerats, såsom minskad framgång i aktiviteter till exempel födosök, aggressiv konkurrens, uppvakning och ungvård. En minskad framgång i födosök kan komma att påverka värdens tillväxt och därmed överlevnad.I denna studie undersöktes påverkan av flodpärlmusslans larver på öringars tillväxt, konditionsfaktor, och rörelsemönster. Analyser av data från två studieområden i Älgåälven indikerade att flodpärlmusslans larver inte har någon signifikant påverkan på värdens tillväxt eller konditionsfaktorn. Regressionsanalyser visade även att det inte finns något signifikant samband mellan infektionsgraden och konditionsfaktorn.Resultaten tydde även på att flodpärlmusslans larver inte påverkar öringens rörelseförmåga då ingen signifikant skillnad i antal stationära individer kunde påvisas mellan låg- och höginfekterade öringar. Analyserna indikerade även på att det inte fanns någon signifikant skillnad i antal uppströms/nedströms mellan höginfekterade och låginfekterade individer. Det fanns inte heller någon signifikant skillnad i hur långt en individ förflyttade sig beroende på deras infektionsgrad. Sammantaget verkar det som att parasitinfektionen inte har någon stor negativ påverkan på värden.

  • 44.
    Balk, Lennart
    et al.
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Hagerroth, Per-Ake
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Gustavsson, Hanna
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Sigg, Lisa
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Åkerman, Gun
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Ruiz Munoz, Yolanda
    Univ Vigo, Dept Biochem, Genet & Immunol, Lagoas Marcosende, ES-36310 Vigo, Spain.
    Honeyfield, Dale C.
    Leetown Sci Ctr, No Appalachian Res Lab, S Geol Survey USGS, Wellsboro, PA 16901 USA.
    Tjärnlund, Ulla
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Oliveira, Kenneth
    Univ Massachusetts Dartmouth, Dept Biol, Dartmouth, MA 02747 USA.
    Strom, Karin
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.;Karolinska Inst, Dept Med Solna & Ctr Mol Med, SE-17176 Stockholm, Sweden.
    McCormick, Stephen D.
    Leetown Sci Ctr, Conte Anadromous Fish Res Lab, S Geol Survey USGS, Turners Falls, MA 01376 USA.
    Karlsson, Simon
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper. Swedish Univ Agr Sci SLU, Inst Freshwater Res, Dept Aquat Resources, SE-17893 Drottningholm, Sweden..
    Ström, Marika
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden..
    van Manen, Mathijs
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.;Univ Utrecht, Inst Risk Assessment Sci IRAS, NL-3508 TD Utrecht, Netherlands..
    Berg, Anna-Lena
    Med Prod Agcy, Box 26, SE-75103 Uppsala, Sweden..
    Halldorsson, Halldor P.
    Univ Icelands Res Ctr Sudurnes, IS-245 Sandgerdi, Iceland..
    Strömquist, Jennie
    Swedish Univ Agr Sci SLU, Inst Freshwater Res, Dept Aquat Resources, SE-17893 Drottningholm, Sweden..
    Collier, Tracy K.
    NW Fisheries Sci Ctr, NOAA Fisheries, Seattle, WA 98112 USA..
    Börjeson, Hans
    Swedish Univ Agr Sci SLU, Fisheries Res Stn, 13Department Aquat Resources, Brobacken, SE-81494 lvkarleby, Sweden..
    Morner, Torsten
    Natl Vet Inst SVA, Dept Dis Control & Epidemiol, SE-75189 Uppsala, Sweden..
    Hansson, Tomas
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden..
    Widespread episodic thiamine deficiency in Northern Hemisphere wildlife2016Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, artikkel-id 38821Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Many wildlife populations are declining at rates higher than can be explained by known threats to biodiversity. Recently, thiamine (vitamin B-1) deficiency has emerged as a possible contributing cause. Here, thiamine status was systematically investigated in three animal classes: bivalves, ray-finned fishes, and birds. Thiamine diphosphate is required as a cofactor in at least five life-sustaining enzymes that are required for basic cellular metabolism. Analysis of different phosphorylated forms of thiamine, as well as of activities and amount of holoenzyme and apoenzyme forms of thiaminedependent enzymes, revealed episodically occurring thiamine deficiency in all three animal classes. These biochemical effects were also linked to secondary effects on growth, condition, liver size, blood chemistry and composition, histopathology, swimming behaviour and endurance, parasite infestation, and reproduction. It is unlikely that the thiamine deficiency is caused by impaired phosphorylation within the cells. Rather, the results point towards insufficient amounts of thiamine in the food. By investigating a large geographic area, by extending the focus from lethal to sublethal thiamine deficiency, and by linking biochemical alterations to secondary effects, we demonstrate that the problem of thiamine deficiency is considerably more widespread and severe than previously reported.

  • 45. Batool, Mustafa Kamil
    Stressnivå hos öring (Salmo trutta) - effekt  temperatur och predatornärvaro: Kortisolnivåer hos öring i akvariemiljö vid minskad temperatur och vid närvaro av lake (Lota lota)2018Student paper other, 10 poäng / 15 hpOppgave
  • 46.
    Bengtson, Johanna
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper.
    The relationship between behaviour and metabolic rate of juvenile Brown trout Salmo trutta2009Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    In salmonids, the decision to migrate or remain resident is influenced by the status, and hence condition, of individuals. Status has been suggested to arise from the temperament of fish. In this study the links between standard metabolic rate and the levels of aggressiveness and shy/boldness were examined for 0+, hatchery-raised brown trout (Salmo trutta). I hypothesized, from the results of earlier studies (Cutts et al., 1998; Yamamoto et al., 1998), that high metabolic rates (MR) would be positively correlated to levels of aggression and boldness. The study was conducted in 200 L aquaria in which aggressiveness was measured by allowing each fish to interact with a mirror image of itself, and shy/boldness was tested by measuring the amount of time a fish used before exploring a new area. Standard metabolic rate was measured in a flow-through respirometer. In contrast to my expectations, there was no correlation between the different behavioural measures and the metabolic rate of fish. Also, no correlation between boldness and aggressiveness of fish was found. In additional testing aggressiveness correlated positively with the condition of fish (in coherence with Harwood et al., 2003) but, contrary to earlier studies (Överli et al., 2004; Schjolden & Winberg, 2007), not with the speed of acclimatization. The difference in results between this test and earlier studies, concerning the degree of correlation between MR and aggressiveness, suggests that the strength of this link differs between species of salmonids. Also, it may suggest changeability in the MR – behaviour link in different environments. Last, the status and condition of individuals cannot be unambiguously explained by temperament alone, but arise from a wider array of physiological and environmental factors.

     

  • 47.
    Bengtsson, Linda
    Karlstads universitet.
    Miljövård på förskolan: Förskolans arbete med att göra barnen delaktiga i att värna om sin miljö.2007Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    The aim of the present study was to investigate if and how pre-school teachers reach the objectives in the national curriculum concerning the environmental issues.

    Another angle of this study is to find out if there are any involvement amongst the preschools regarding the environmental issues and if the teachers encourage the children to join in and make them a part of discussion.

    I have randomly chosen 10 preschools throughout Sweden and interviewed one staff-member from each school. Most of the preschools were well aware of the goals to follow according to the national curriculum.

    After comparing the answers my conclusion is that preschools act quite differently concerning environmental issues. Some worked almost exclusively with the children involved. Others occasionally involved the children whereas a few didn’t include the children at all.

    In every case the teachers would want to dedicate more time to environmental issues. However, lack of time is one big reason they can’t do that. Many of the teachers wanted to learn more about how to best educate and involve the children.

  • 48.
    Bengtsson, Mikael
    Karlstads universitet, Institutionen för natur och miljö.
    Utvärdering av omlöp vid Finsjö i Emån: Evaluation of natural fishways at Finsjö in the river Emån2009Oppgave
    Abstract [sv]

    Syftet med denna uppsats är att undersöka huruvida fiskvägar förbi vattenkraftverket vid Finsjö i Emån fungerar eller inte. För att finna svar på den frågan har två olika metoder använts, dels telemetrisändare för att se om fiskar hittar fram till fiskvägarna (attraktionseffektivitet) och dels PIT-tags för att mäta om fiskarna lyckas passera genom fiskvägarna (passageeffektivitet). Undersökningen fann att det var en högre passageeffektivitet, 89 % vid nedre Finsjö och 100 % vid övre Finsjö, i Emån jämfört med andra liknande studier. Attraktionseffektiviteten var 75 % vid nedre Finsjö och 59 % vid övre Finsjö, vilket tyder på att det finns något som stör fisken innan de når fram till fiskvägen, särskilt vid övre Finsjö.

  • 49. Bergengren, Jakob
    et al.
    Olsson, Ivan
    Österling, Martin
    Karlstads universitet, Fakulteten för samhälls- och livsvetenskaper, Avdelningen för biologi.
    The thick shelled river mussel (Unio crassus) brings LIFE+ back to rivers.2012Konferansepaper (Fagfellevurdert)
  • 50.
    Berggren, Åsa
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013).
    Predatorinducerad fekunditet hos Daphnia pulex vid simulerade årstidsbundna temperaturvariationer2015Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Female growth, number of eggs and egg growth of Daphnia pulex were studied at four temperatures, 12, 16, 18 and 20°C. I hypothesized that female growth and number of eggs would be lower and the size of the eggs larger in the presence of a predator (kairomones) than in its absence. This effect was expected to be more evident at lower temperatures. I could not find any effect of kairomones on female growth, number of eggs or egg size, although there was a weak tendency for an effect on number of eggs. There was, however, an effect of temperature, regardless of predator treatment (i. e. presence vs absence of kairomones), on number of eggs, where females produced fewer numbers of eggs with increasing temperature. The effect temperature on the number of eggs was not anticipated. Two of the temperatures, 12 and 18°C, were carried out in darkness due to malfunctioning equipment. In addition, for some unknown reason, a high ratio between the number of ephippia and eggs occurred at at16 and 18°C, regardless of predator treatment. These complicating factors (darkness and ephippia) can have had a negative effect on detecting a response by Daphnia to kairomones.

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