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  • 1.
    Abdel–Khalik, Jonas
    et al.
    Institute of Mass Spectrometry, College of Medicine, Swansea University.
    Björklund, Erland
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Hansen, Martin
    Department of Civil & Environmental Engineering, Stanford University.
    Simultaneous determination of endogenous steroid hormones in human and animal plasma and serum by liquid or gas chromatography coupled to tandem mass spectrometry2013Inngår i: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 928, nr June, 59-77 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Analytical methodologies based on liquid or gas chromatography coupled to tandem mass spectrometry for the simultaneous determination of two or more endogenous steroid hormones in human and animal plasma and serum has received increased attention the last few years. Especially in the clinical setting steroid profiling is of major importance in disease diagnostics. This paper discusses recent findings in such multi-steroid hormone procedures published from 2001 to 2012. The aim was to elucidate possible relationships between chosen analytical technique and the obtained analyte sensitivity for endogenous steroid hormones. By evaluating the success, at which the currently applied techniques have been utilized, more general knowledge on the field is provided. Furthermore the evaluation provides directions in which future studies may be interesting to conduct.

  • 2.
    Abdel-Khalik, Jonas
    et al.
    England.
    Björklund, Erland
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Plattformen för molekylär analys.
    Nielsen, Frederik Knud
    Danmark.
    Hansen, Martin
    Danmark.
    Incorporation of (14)C-cholesterol in human adrenal corticocarcinoma H295R cell line and online-radiodetection of produced (14)C-steroid hormone metabolites2017Inngår i: Journal of Pharmaceutical and Biomedical Analysis, ISSN 0731-7085, E-ISSN 1873-264X, Vol. 145, 569-575 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study demonstrates the addition of (14)C-cholesterol to the human cell line H295R will in-situ form radiolabeled steroid hormones allowing for new mechanistic and metabolic insights. The aim of the present study was to in-situ radiolabel steroid hormones from cell line-incorporated (14)C-cholesterol using the OECD guideline 456, H295R steroidogenesis in-vitro assay. Radiodetection of the steroid metabolites of the steroidogenic pathway allows for an improved understanding of the various enzymatic mechanisms involved without necessarily being dependent on quantification. Generated radiolabeled steroids were analyzed using HPLC hyphenated with a Flow Scintillation Analyzer (FSA). H295R cells were incubated with radiolabeled cholesterol and cell media were collected and prepared by solid phase extraction and analyzed with HPLC-FSA. For successful radiolabeling of the steroids in the steroidogenesis of H295R cells, radioactive cholesterol may potentially only need to be added just before the cells are incubated for 72h in well plates. Based on the obtained HPLC-FSA chromatograms, and confirmation of the observations by studies in the literature, a qualitative time profile for the production of steroid hormones was estimated. Multiple radiolabeled steroid hormones were identified by means of analytical standards and UV (ultraviolet) co-chromatography, though the elucidation of multiple metabolites remains unresolved. Although online radiodetection proved to suffer from suboptimal sensitivity, the concept of radiolabeling the steroidogenesis in H295R cells with (14)C-cholesterol and detecting the radiolabeled steroid hormones online was proved and may assist in further toxicological studies.

  • 3.
    Ahlén, Ingemar
    et al.
    SLU.
    Angelstam, Per
    SLU.
    Bensch, Staffan
    Lunds universitet.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Enemar, Anders
    Göteborgs universitet.
    Fagerström,, Torbjörn
    SLU.
    Green, Martin
    Lunds universitet.
    Gustafsson, Lars
    Uppsala universitet.
    Gustafsson, Lena
    SLU.
    Mikael, Hake
    SLU.
    Dennis, Hasselquist,
    Lunds universitet.
    Hedenström, Anders
    Lunds universitet.
    H-Lindgren, Christina
    Umeå universitet.
    Lindberg, Peter
    Göteborgs universitet.
    Lindström, Åke
    Lunds universitet.
    Michanek, Gabriel
    Luleå tekniska universitet.
    Nilsson, Leif
    Lunds universitet.
    Nilsson, Sven G
    Lunds universitet.
    Pärt, Tomas
    SLU.
    Sundberg, Jan
    Uppsala universitet.
    Svensson, Sören
    Lunds universitet.
    Tjernberg, Martin
    SLU.
    Ulfstrand, Staffan
    Uppsala universitet.
    Brusewitz, Gunnar
    Stockholms universitet.
    Edman, Stefan
    Chalmers tekniska högskola.
    Jonsson, Lars
    Uppsala universitet.
    Landell, Nils-Erik
    Wahlstedt, Jens
    Emanuelsson, Urban
    Centrum för biologisk mångfald.
    Ingelög, Torleif
    Artdatabanken.
    Karlsson, Mikael
    Svenska naturskyddsföreningen.
    Kristoferson, Lars
    WWF.
    Lindell, Lars
    Sveriges Ornitologiska Förening.
    Nya järnvägen hotar unikt naturområde2002Inngår i: Aftonbladet, ISSN 1103-9000Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 4.
    Alho, Jussi S.
    et al.
    Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki.
    Herczeg, Gábor
    Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki.
    Söderman, Fredrik
    Population and Conservation Biology, Department of Ecology and Evolution, Evolutionary Biology Centre, Uppsala University.
    Laurilla, Anssi
    Population and Conservation Biology, Department of Ecology and Evolution, Evolutionary Biology Centre, Uppsala University.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Merilä, Juha
    Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki.
    Increasing melanism along a latitudinal gradient in a widespread amphibian: local adaptation, ontogenic or environmental plasticity?2010Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 10, 317- s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BackgroundThe thermal benefits of melanism in ectothermic animals are widely recognized, but relatively little is known about population differentiation in the degree of melanism along thermal gradients, and the relative contributions of genetic vs. environmental components into the level of melanism expressed. We investigated variation in the degree of melanism in the common frog (Rana temporaria; an active heliotherm thermoregulator) by comparing the degree of melanism (i) among twelve populations spanning over 1500 km long latitudinal gradient across the Scandinavian Peninsula and (ii) between two populations from latitudinal extremes subjected to larval temperature treatments in a common garden experiment.

    ResultsWe found that the degree of melanism increased steeply in the wild as a function of latitude. Comparison of the degree of population differentiation in melanism (PST) and neutral marker loci (FST) revealed that the PST > FST, indicating that the differences cannot be explained by random genetic drift alone. However, the latitudinal trend observed in the wild was not present in the common garden data, suggesting that the cline in nature is not attributable to direct genetic differences.

    ConclusionsAs straightforward local adaptation can be ruled out, the observed trend is likely to result from environment-driven phenotypic plasticity or ontogenetic plasticity coupled with population differences in age structure. In general, our results provide an example how phenotypic plasticity or even plain ontogeny can drive latitudinal clines and result in patterns perfectly matching the genetic differences expected under adaptive hypotheses. 

  • 5.
    Andersson, Robert
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Fenologisk studie av björk (Betula alba) och ek (Quercus robur): En regional jämförelse av historiska och nutida fenologi- och temperaturdata2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Med ett allt varmare klimat har observationer av främst växter visat sig vara värdefulla för vilka effekter en klimatförändring kan få på ekosystemen. Observationer av tidpunkten för dessa företeelser är det som benämns fenologi och utgör enligt flera studier indikationer på att jordens klimat förändras. Målet med min undersökning är att se om klimatförändringar har påverkat lövsprickningen i södra Sverige. För att mer specifikt undersöka tidpunkten för lövsprickning har jag avgränsat mig till björk (Betula alba) och ek (Quercus robur) i fyra län i södra Sverige. För att undersöka eventuella fenologiska förändringar har jag använt/jämfört historiska data från 1873–1923 med nutida 2008–2016 och beräknat hur lövsprickningsdatumen och temperatur har förändrats. För att kunna undersöka sambandet mellan lövsprickning och temperatur har månadsmedeltemperaturen använts för jämförelse tre månader bakåt räknat från lövsprickningsdatum. Resultatet visade att både temperaturen och lövsprickningen har förändrats. I undersökningsområdet har medeltemperaturen i genomsnitt ökat med 2°C, medan lövsprickningen har tidigarelagts för björk och ek med 16,5 respektive 11,5 dagar i genomsnitt. Resultatet visar också att de fenologiska förändringarna är statistiskt signifikanta. Däremot är det mer osäkert att förändringarna beror på temperaturen, trots starka kopplingar mellan temperaturförändringarna och fenologiska förändringar. Det skulle kunna vara variationen i temperaturen, snarare än medeltemperaturen som är viktigast för lövsprickningen.

  • 6.
    Andiappan, Anand Kumar
    et al.
    Department of Biological Sciences, National University of Singapore.
    Nilsson, Daniel
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Biomedicin.
    Halldén, Christer
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Biomedicin.
    Yun, Wang De
    Department of Otolaryngology, National University of Singapore.
    Säll, Torbjörn
    Department of Cell and Organism Biology, Lund University.
    Cardell, Lars Olaf
    Division of ENT Diseases, CLINTEC, Karolinska Institutet.
    Tim, Chew Fook
    Department of Biological Sciences, National University of Singapore.
    Investigating highly replicated asthma genes as candidate genes for allergic rhinitis2013Inngår i: BMC Medical Genetics, ISSN 1471-2350, E-ISSN 1471-2350, Vol. 14, 51- s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Asthma genetics has been extensively studied and many genes have been associated with the development or severity of this disease. In contrast, the genetic basis of allergic rhinitis (AR) has not been evaluated as extensively. It is well known that asthma is closely related with AR since a large proportion of individuals with asthma also present symptoms of AR, and patients with AR have a 5-6 fold increased risk of developing asthma. Thus, the relevance of asthma candidate genes as predisposing factors for AR is worth investigating. The present study was designed to investigate if SNPs in highly replicated asthma genes are associated with the occurrence of AR.

    METHODS: A total of 192 SNPs from 21 asthma candidate genes reported to be associated with asthma in 6 or more unrelated studies were genotyped in a Swedish population with 246 AR patients and 431 controls. Genotypes for 429 SNPs from the same set of genes were also extracted from a Singapore Chinese genome-wide dataset which consisted of 456 AR cases and 486 controls. All SNPs were subsequently analyzed for association with AR and their influence on allergic sensitization to common allergens.

    RESULTS: A limited number of potential associations were observed and the overall pattern of P-values corresponds well to the expectations in the absence of an effect. However, in the tests of allele effects in the Chinese population the number of significant P-values exceeds the expectations. The strongest signals were found for SNPs in NPSR1 and CTLA4. In these genes, a total of nine SNPs showed P-values <0.001 with corresponding Q-values <0.05. In the NPSR1 gene some P-values were lower than the Bonferroni correction level. Reanalysis after elimination of all patients with asthmatic symptoms excluded asthma as a confounding factor in our results. Weaker indications were found for IL13 and GSTP1 with respect to sensitization to birch pollen in the Swedish population.

    CONCLUSIONS: Genetic variation in the majority of the highly replicated asthma genes were not associated to AR in our populations which suggest that asthma and AR could have less in common than previously anticipated. However, NPSR1 and CTLA4 can be genetic links between AR and asthma and associations of polymorphisms in NPSR1 with AR have not been reported previously.

  • 7.
    Arvidsson, Fredrik
    et al.
    Lund University.
    Jonsson, Lars J.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Birkhofer, Klaus
    Lund University.
    Geographic location, not forest type, affects the diversity of spider communities sampled with malaise traps in Sweden2016Inngår i: Annales Zoologici Fennici, ISSN 0003-455X, E-ISSN 1797-2450, Vol. 53, nr 3-4, 215-227 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The latitudinal diversity gradient predicts higher species richness at lower latitudes. Here, we utilize the data from a long-term monitoring with malaise traps to analyse if spider communities in Sweden are affected by geographic gradients and if these effects hold independent of forest type. The species richness and the effective number of species in spider communities were not significantly related to the latitudinal gradient. The effective number of species and the taxonomic distinctness of spider communities were related to longitude, with a higher number, but fewer related species in western parts of Sweden. The species and family composition were significantly related to latitude independent of forest type, with a dominance of Linyphiidae individuals and species in the north. Our study demonstrates the suitability of malaise trap sampling to contribute to a better understanding of local spider communities, as several rare and locally new species were recorded in this study.

  • 8.
    Arzel, C.
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, M.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    A flyway perspective of foraging activity in Eurasian Green-winged Teal, Anas crecca crecca2007Inngår i: Canadian Journal of Zoology, ISSN 0008-4301, E-ISSN 1480-3283, Vol. 85, nr 1, 81-91 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Time-activity budgets in the family Anatidae are available for the wintering and breeding periods. We present the first flyway-level study of foraging time in a long-distance migrant, the Eurasian Green-winged Teal, Anas crecca crecca L., 1758 ("Teal"). Behavioral data from early and late spring staging, breeding, and molting sites were collected with standardized protocols to explore differences between the,sexes, seasons, and diel patterns. Teal foraging activity was compared with that of the Mallard, Anas platyrhynchos L., 1758 and Northern Shoveler, Anas clypeata L., 1758, and the potential effects of duck density and predator-caused disturbance were explored. In early spring, foraging time was moderate (50.5%) and mostly nocturnal (45%). It increased dramatically in all three species at migration stopovers and during molt, mostly because of increased diurnal foraging, while nocturnal foraging remained fairly constant along the flyway. These patterns adhere to the "income breeding" strategy expected for this species. No differences between the sexes were recorded in either species studied. Teal foraging time was positively correlated with density of Teal and all ducks present, but negatively correlated with predator disturbance. Our study suggests that Teal, in addition to being income breeders, may also be considered as income migrants; they find the energy necessary to migrate at staging sites along the flyway.

  • 9.
    Arzel, C.
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, M.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Gurd, D.B.
    Centre for Wildlife Ecology, Department of Biological Sciences, Simon Fraser University, Burnaby, BC.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Fritz, H.
    Centre d’Etudes Biologiques de Chizé, CNRS UPR 1934, Beauvoir-sur-Niort.
    Arnaud, A.
    Station Biologique La Tour du Valat, Le Sambuc, Arles.
    Pin, C.
    Station Biologique La Tour du Valat, Le Sambuc, Arles.
    Bosca, F.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Experimental functional response and inter-individual variation in foraging rate of teal (Anas crecca)2007Inngår i: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 75, nr 1, 66-71 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The functional response, i.e. the change in per capita food intake rate per time unit with changed food availability, is a widely used too] for understanding the ecology and behaviour of animals. However, waterfowl remain poorly explored in this context. In an aviary experiment we derived a functional response curve for teal (Anas crecca) foraging on rice (Oryza sativa) seeds. We found a linear relationship between intake rate and seed density, as expected for a filter-feeder. At high seed densities we found a threshold, above which intake rate still increased linearly but with a lower slope, possibly reflecting a switch from filter-feeding to a scooping foraging mode. The present study shows that food intake rate in teal is linearly related to food availability within the range of naturally occurring seed densities, a finding with major implications for management and conservation of wetland habitats.

  • 10.
    Arzel, Céline
    et al.
    Department of Biology, University of Turku.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Nummi, Petri
    Pöysä, Hannu
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Sjöberg, Kjell
    Does changing spring phenology affect short and long distance migratory waterfowl similarly?2010Inngår i: The abstract book: Symposium : The global environmental change: messages from birds. Espoo, 17-19 November, 2010, 43- s.Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Among waterfowl, most ducks may be considered income breeders due to their small body size and their limited capacity to store energy. Therefore limited access to resources on their breeding grounds is likely to affect their breeding schedule and potentially output. At northern latitudes, ice break up dictates the access to the breeding lakes. An early ice break up allows for early access to the breeding site and its feeding resources, and potentially leading to higher breeding output than after a late ice break up. Short distance migrants are thus more likely to adapt to ice break up conditions than long distance migrants which have to cope with weather conditions en route and local resource accessibility along the migratory path. Using 20 years of data on breeding phenology and success of 3 species of ducks differing in their migratory strategy - Teal Anas crecca, Mallard Anas platyrhynchos and Common Goldeneye Bucephala clangula - in a watershed in Finland, we test the idea that variation in spring phenology affects the reproductive performance of duck species differently depending on their migration pattern.

  • 11.
    Arzel, Céline
    et al.
    Finland.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Nummi, Petri
    Finland.
    Pöysä, Hannu
    Finland.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Sjöberg, Kjell
    SLU, Umeå.
    Effect of the timing of spring thaw on the breeding performance in two sympatric bird species: does migration distance matter?2011Konferansepaper (Fagfellevurdert)
  • 12.
    Arzel, Céline
    et al.
    University of Turku.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Pöysä, Hannu
    Joensuu Game and Fisheries Research.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Nummi, Petri
    University of Helsinki.
    Sjöberg, Kjell
    Swedish University of Agricultural Sciences, Umeå.
    Early springs and breeding performance in two sympatric duck species with different migration strategies2014Inngår i: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 156, nr 2, 288-298 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The capacity of migratory species to adapt to climate change may depend on their migratory and reproductive strategies. For example, reproductive output is likely to be influenced by how well migration and nesting are timed to temporal patterns of food abundance, or by temperature variations during the brood rearing phase. Based on two decades (1988–2009) of waterfowl counts from a boreal catchment in southern Finland we assessed how variation in ice break-up date affected nesting phenology and breeding success in two sympatric duck species, Mallard Anas platyrhynchos and Eurasian Teal Anas crecca. In Fennoscandia these species have similar breeding habitat requirements but differ in migration distance; Teal migrate roughly seven times as far as do Mallard. Annual ice break-up date was used as a proxy of spring ‘earliness’ to test the potential effect of climate change on hatching timing and breeding performance. Both species were capable of adapting their nesting phenology, and bred earlier in years when spring was early. However, the interval from ice break-up to hatching tended to be longer in early springs in both species, so that broods hatched relatively later than in late springs. Ice break-up date did not appear to influence annual number of broods per pair or annual mean brood size in either species. Our study therefore does not suggest that breeding performance in Teal and Mallard is negatively affected by advancement of ice break-up at the population level. However, both species showed a within-season decline in brood size with increasing interval between ice break-up and hatching. Our study therefore highlights a disparity between individuals in their capacity to adjust to ice break-up date, late breeders having a lower breeding success than early breeders. We speculate that breeding success of both species may therefore decline should a consistent trend towards earlier springs occur.

  • 13.
    Arzel, Céline
    et al.
    Frankrike.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Pöysä, Hannu
    Finland.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Nummi, Petri
    Finland.
    Sjöberg, Kjell
    SLU, Umeå.
    Effect of the timing of spring thaw on the breeding performance in two sympatric waterbirds species2012Inngår i: Third Pan-European Duck Symposium: abstract book and programme, 2012, 51- s.Konferansepaper (Fagfellevurdert)
  • 14.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Time and microhabitat use in pre-breeding dabbling ducks Anas spp. in sub-arctic Norway: does the long trip make a difference?2009Inngår i: Abstracts, 2nd Pan-European Duck Symposium, 2009, 44- s.Konferansepaper (Fagfellevurdert)
  • 15.
    Arzel, Céline
    et al.
    Turku University.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Time use and foraging behaviour in pre-breeding dabbling ducks Anas spp. in sub-arctic Norway2015Inngår i: Journal of Ornithology, ISSN 2193-7192, E-ISSN 2193-7206, Vol. 156, nr 2, 499-513 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We studied time budgets and foraging methods in pre-breeding Mallard Anas platyrhynchos, (Eurasian) Teal Anas crecca, Wigeon Anas penelope, Pintail Anas acuta, Shoveler Anas clypeata and Gadwall Anas strepera in subarctic Norway in May. Among all six species studied, foraging accounted for the most common use of time, ranging from 19 % in male Pintail to 40–60 % in female Mallard, Teal, Pintail and Gadwall. Comfort behaviours amounted to 20–34 % of the time budget, and interaction and disturbance were marginal. Vigilance time ranged from 8 % in female Mallard to 20 % in male Pintail. Movement amounted to some 20 % of the time in most species and sexes. In Wigeon, sexes did not differ in time use, whereas in Mallard, Pintail and, in particular, Teal, females foraged more and engaged less in vigilance and interactions than did males. In addition, Teal and Mallard males engaged in the riskier foraging methods less than females, but more in those permitting vigilance. Although overlap in feeding methods was large among these species, Mallard and Teal were generalists, feeding at all depths, Wigeon foraged mainly in shallow water and Pintail foraged essentially in deep water. Our results support the income/capital breeder hypothesis with respect to males only; compared to lighter species, heavier species allocated less time to foraging but more to vigilance. We found no support for the hypothesis that long-distance migrants forage more to compensate for energy loss due to migratory flight. Foraging time in females was related to breeding phenology; early nesters spent more time feeding than later nesters.

  • 16. Arzel, Céline
    et al.
    Elmberg, Johan
    Time use, foraging behavior and microhabitat use in a temporary guild of spring-staging dabbling ducks (Anas spp.)2004Inngår i: Ornis Fennica, ISSN 0030-5685, Vol. 81, nr 4, 157-168 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dabbling ducks were studied on a eutrophic mid-flyway staging site in spring. Six species made up a temporary guild, in order of decreasing abundance they were: Teal (Anas crecca), Shoveler (A. clypeata), Mallard (A. platyrhynchos), Wigeon (A. penelope), Pintail (A. acuta), and Garganey (A. querquedula). Species richness and total abundance peaked around 20 April, whereas guild evenness was highest after the staging peak. Time use during the staging peak differed between the sexes in Mallard, but not in the other species. Mallard spent the least time foraging, whereas Shoveler and Teal foraged the most. Foraging behavior differed among species; i.e. Wigeon was mainly on land, Shoveler mainly fed from the water surface, whilst Mallard and Teal were more generalist. For the guild as a whole, shallow inshore areas were overused compared to offshore habitats. Microhabitat use of foraging birds differed among species; Pintail and Shoveler mainly fed in the offshore end of the habitat gradient, whereas Teal, Garganey, female Mallard, and especially Wigeon used shallow microhabitats. Teal and female Mallard had the highest overlap in microhabitat use, Shoveler and Wigeon had the least. Abundance of invertebrate prey was low during the staging peak, but increased sharply thereafter. This study indicates that eutrophic mid-flyway sites may offer less food to staging birds than do breeding lakes to which many of them are headed.

  • 17.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, M.
    CNERA Avifaune Migratrice, Office National de la Chasse et de la Faune Sauvage, La Tour du Valat, Le Sambuc, Arles.
    Ecology of spring-migrating Anatidae: a review2006Inngår i: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 147, nr 2, 167-184 s.Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Spring migration is generally considered as a crucial period of the year for many birds, not the least due to its supposed importance for subsequent breeding success. By reviewing the existing literature for Anatidae (ducks, geese, and swans), we show that little is known about their ecology in spring, although some goose species are exceptions. Another general pattern is that the ecology of Anatidae at staging sites is particularly neglected. Existing studies tend to focus on questions dealing with acquisition of nutrient reserves, whereas almost nothing has been published about stopover habitats, time use, microhabitat use, foraging behaviour, food availability, food limitation, diet selection, and interspecific relationships. Besides summarising present knowledge, we identify taxonomic groups and topics for which gaps of knowledge appear the most evident, thereby also highlighting research needs for the future.

  • 18.
    Arzel, Céline
    et al.
    Finland.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Guillemain, Matthieu
    Frankrike.
    A flyway approach to dabbling ducks foraging ecology: food availability vs foraging behaviour2007Inngår i: Book of abstracts: International Union of Game Biologists XXVIII Congress, 13-18 August, 2007, Uppsala Sweden / [ed] K. Sjöberg & T. Rooke, 2007, 283- s.Konferansepaper (Fagfellevurdert)
  • 19.
    Arzel, Céline
    et al.
    Frankrike.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Guillemain, Matthieu
    Frankrike.
    Does foraging in Teal Anas crecca depend on season and disturbance by predators?2006Inngår i: Integrating science and duck management: the 4th North American Duck Symposium and Workshop, 2006, 131- s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    To ensure wise management of migratory species it is crucial to know their energy requirements throughout their biological cycle, especially during periods like spring migration, that might affect future breeding success. Surprisingly, this period has seldom been studied. To start filling this gap for dabbling ducks and especially Eurasian Teal Anas crecca, we studied their foraging time and foraging methods along their Western European flyway from wintering to breeding grounds. Differences in foraging activity between sexes, species, years, seasons, sites and diel patterns were checked, as well as potential effects of disturbances by potential predators. Ducks of both sexes presented a fairly constant nocturnal foraging along the flyway, whereas diurnal foraging increased at periods of high requirements (spring, breeding, moulting). Ducks might thus not only be income breeders, but also income migrators (relying on the food they encounter along their flyway to fuel their travel). Moreover, Teal foraging depth increased along the flyway when disturbance due to potential predators decreased. This probably reflects their diet switch (from granivorous to carnivorous). The decrease in predator pressure probably makes it possible for teals to use riskiest behaviors (greater depths associated to eyes underwater and less prevention of predators).We thus highlight the need for adequate management of staging wetlands all along the flyway, since ducks have to fulfill high energy requirements there. Water level control may be useful to provide more shallow foraging habitats in which they can use less risky foraging techniques at times when nutrient needs increases and predation risk is relatively high.

  • 20.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Waterfowl migration and wetland management at the European scale2009Inngår i: Abstracts, 2nd Pan-European Duck Symposium, 2009, 33- s.Konferansepaper (Fagfellevurdert)
  • 21.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, Matthieu
    Frankrike.
    Legagneux, Pierre
    Frankrike.
    Bosca, Fabrice
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Chambouleyron, Mathieu
    Frankrike.
    Lepley, Michel
    Frankrike.
    Pin, Christophe
    Frankrike.
    Arnaud, Antoine
    Frankrike.
    Schricke, Vincent
    Frankrike.
    Average mass of seeds encountered by foraging dabbling ducks in western Europe2007Inngår i: Wildlife Biology, ISSN 0909-6396, E-ISSN 1903-220X, Vol. 13, nr 3, 328-336 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Many dabbling ducks Anas spp. are largely granivorous, consuming a variety of seeds chiefly from aquatic plants. To assess the relative value and carrying capacity of wetlands for dabbling ducks, species-specific information about seed mass is needed, but it is still largely missing or scattered in the literature. By combining weights of seeds collected in the field with a literature review, we provide a reference table for seed mass of 200 western European plant taxa frequently encountered by foraging dabbling ducks. Seeds collected in the field were sampled in microhabitats and at depths at which ducks were observed to forage, and study sites represent wintering, staging as well as breeding areas within a flyway in western Europe. When combined with calorimetric data, the present reference table will aid managers and scientists in assessing the importance of seed food resources at different sites and during different parts of the annual cycle.

  • 22.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Lepley, Michel
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Bosca, Fabrice
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Legagneux, Pierre
    CEBC, CNRS UPR 1934 Villiers-en-Bois, Beauvoir sur Niort.
    Nogues, Jean-Baptiste
    Les Amis des Marais du Vigueirat, Mas Thibert, Arles.
    A flyway perspective on food resource abundance in a long-distance migrant, the Eurasian teal (Anas crecca)2009Inngår i: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 150, nr 1, 61-73 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two frequent assumptions about the evolution of long-distance migration in birds are that they travel long distances annually to reach food-rich areas for breeding, and that they time their migratory journey to be at staging sites when the latter provide the best feeding conditions. These assumptions have rarely been properly tested, and there is no study in which a species’ major food types have been measured by standardized methods throughout a flyway and over a large part of the year. We here present such data for Eurasian teal (Anas crecca), converted to a common energetic currency, and collected at wintering, spring staging and breeding sites. Teal did not time migration to maximize local food abundance; most birds left wintering and spring staging sites before a sharp increase in invertebrate food abundance occurred. On the other hand, hatching of ducklings coincided with a peak in invertebrate food abundance on boreal breeding lakes. Mean overall food abundance (invertebrates and seeds combined) did not differ between wintering sites in southern France and breeding sites in northern Sweden at the time of breeding. Our results are inconsistent with the hypothesis that long-distance migration in dabbling ducks has evolved because adult birds gain an immediate pay-off in increased food abundance by flying north in spring. However, our data confirm a selective advantage for breeding at higher latitudes, because hatching of ducklings may coincide with a peak in invertebrate emergence and because longer days may increase the duration of efficient foraging.

  • 23.
    Arzel, Céline
    et al.
    Frankrike.
    Guillemain, Matthieu
    Frankrike.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Individual strategies of dabbling ducks: a circum-annual perspectice2003Inngår i: Third North American duck symposium: waterfowl management and biology in the 21st century: looking back and to the future, 2003, 73- s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Very little is still known about the ecology of dabbling ducks on staging areas in spring, despite the fact that this is a crucial period of the year when birds refuel during migration and prepare for subsequent reproduction. This lack of knowledge translates into the current inability to predict the consequences of changes in the environment and harvesting for the population dynamics of ducks. We have launched a joint project to study dabbling ducks in the flyway connecting wintering grounds in France with breeding areas in Sweden. The aim is to study individual dabbling ducks in a circumannual perspective. We are assessing food resource limitation, density-dependent effects and the role of competition by estimating available food, by using a reference functional response curve and by recording the foraging behaviour of wild individual dabbling ducks. We also study survival probability and breeding success, and we will assess inter-individual variation. Birds are captured, weighed, marked and subsequently observed in order to study foraging behaviour and potentially measure the changes in body mass across time through recaptures. Ducks are fitted with nasal marks for individual recognition. Eventually, we will provide a model to predict the number of young that a female duck will produce after simple measurements such as its date of arrival on the breeding grounds and its body-mass at this date. Duckling foraging efficiency and survival will be measured and the relationship with corresponding estimates for their mother will be explored.

  • 24.
    Arzel, Céline
    et al.
    Department of Biology, University of Turku.
    Rönkä, Mia
    Davranche, Aurélie
    Erlangen-Nürnberg University Institute of Geography.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Saari, Lennart
    Rainio, Kalle
    Lehikionen, Esa
    Are ducks able to adapt their migratory habits to environmental change?2010Inngår i: The abstract book: Symposium : The global environmental change: messages from birds. Espoo, 17-19 November, 2010, 25- s.Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    In order to predict waterfowl population changes due to variation in climate conditions, and habitat availability it is necessary to precisely understand the mechanisms driving their annual cycle. This is particularly challenging in migratory birds as they encounter a huge variety of habitats along their migratory routes, and different factors might affect their demographic parameters at different stages of their life-cycle. In this perspective spring migration stands out as a crucial period. During spring migration birds need both to complete their migration and to prepare for subsequent reproduction. An understanding of long-term factors influencing the timing of breeding in migratory birds is particularly important in order to predict how they might respond to future environmental changes. Anatidae are particularly interesting to study as they offer a wide variety of migratory strategies. We discuss some of the factors that are likely to affect individual choices and thus play a role in the evolution of migration. Based on long-term data sets, collected over 30 years, in the Archipelago Sea, SW Finland, we also offer a first insight into the changes in their spring arrival and breeding success of ducks in relation to environmental conditions.

  • 25.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Stervander, Martin
    Gunnarsson, Gunnar
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Simändernas ekologi studeras närmare2003Inngår i: Vår fågelvärld, ISSN 0042-2649, Vol. 62, nr 4, 25- s.Artikkel i tidsskrift (Annet vitenskapelig)
  • 26. Arzél, Céline
    et al.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Comportement et alimentation de la Sarcelle d'hiver Anas crecca lors de la migration prénuptial2010Inngår i: Ornithos: revue d'ornithologie de terrain, ISSN 1254-2962, Vol. 17, nr 5, 307-315 s.Artikkel i tidsskrift (Annet vitenskapelig)
  • 27.
    Asplund, Maria E.
    et al.
    Department of Biological and Environmental Sciences, University of Gothenburg.
    Baden, Susanne P.
    Department of Biological and Environmental Sciences, University of Gothenburg.
    Russ, Sarah
    Department of Biological and Environmental Sciences, University of Gothenburg.
    Ellis, Robert P.
    College of Life and Environmental Sciences, University of Exeter.
    Gong, Ningping
    Department of Biological and Environmental Sciences, University of Gothenburg.
    Hernroth, Bodil E.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Ocean acidification and host–pathogen interactions: blue mussels, Mytilus edulis, encountering Vibrio tubiashii2014Inngår i: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 16, nr 4, 1029-1039 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ocean acidification (OA) can shift the ecological balance between interacting organisms. In this study, we have used a model system to illustrate the interaction between a calcifying host organism, the blue mussel Mytilus edulis and a common bivalve bacterial pathogen, Vibrio tubiashii, with organisms being exposed to a level of acidification projected to occur by the end of the 21st century. OA exposures of the mussels were carried out in relative long-term (4 months) and short-term (4 days) experiments. We found no effect of OA on the culturability of V. tubiashii, in broth or in seawater. OA inhibited mussel shell growth and impaired crystalline shell structures but did not appear to affect mussel immune parameters (i.e haemocyte counts and phagocytotic capacity). Despite no evident impact on host immunity or growth and virulence of the pathogen, V. tubiashii was clearly more successful in infecting mussels exposed to long-term OA compared to those maintained under ambient conditions. Moreover, OA exposed V. tubiashii increased their viability when exposed to haemocytes of OA-treated mussel. Our findings suggest that even though host organisms may have the capacity to cope with periods of OA, these conditions may alter the outcome of host–pathogen interactions, favouring the success of the latter.

  • 28.
    Asplund, Maria E.
    et al.
    Department of Marine Ecology, University of Gothenburg.
    Rehnstam-Holm, Ann-Sofi
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Atnur, Vijay
    Department of Fishery Microbiology, College of Fisheries, Karnataka Veterinary Animal and Fisheries Sciences University, Bidar, Karnataka, India.
    Raghunath, Pendru
    Department of Fishery Microbiology, College of Fisheries, Karnataka Veterinary Animal and Fisheries Sciences University, Bidar, Karnataka, India.
    Saravanan, Vasudevan
    Department of Fishery Microbiology, College of Fisheries, Karnataka Veterinary Animal and Fisheries Sciences University, Bidar, Karnataka, India.
    Härnstrom, Karolina
    Department of Marine Ecology, University of Gothenburg.
    Collin, Betty
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Karunasagar, Indrani
    Department of Fishery Microbiology, College of Fisheries, Karnataka Veterinary Animal and Fisheries Sciences University, Bidar, Karnataka, India.
    Godhe, Anna
    Department of Marine Ecology, University of Gothenburg.
    Water column dynamics of Vibrio in relation to phytoplankton community composition and environmental conditions in a tropical coastal area2011Inngår i: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 13, nr 10, 2738-2751 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Vibrio abundance generally displays seasonal patterns. In temperate coastal areas, temperature and salinity influence Vibrio growth, whereas in tropical areas this pattern is not obvious. The present study assessed the dynamics of Vibrio in the Arabian Sea, 1-2 km off Mangalore on the south-west coast of India, during temporally separated periods. The two sampling periods were signified by oligotrophic conditions, and stable temperatures and salinity. Vibrio abundance was estimated by culture-independent techniques in relation to phytoplankton community composition and environmental variables. The results showed that the Vibrio density during December 2007 was 10- to 100-fold higher compared with the February-March 2008 period. High Vibrio abundance in December coincided with a diatom-dominated phytoplankton assemblage. A partial least squares (PLS) regression model indicated that diatom biomass was the primary predictor variable. Low nutrient levels suggested high water column turnover rate, which bacteria compensated for by using organic molecules leaking from phytoplankton. The abundance of potential Vibrio predators was low during both sampling periods; therefore it is suggested that resource supply from primary producers is more important than top-down control by predators.

  • 29. Back, C
    et al.
    Boisvert, J
    Lacoursière, Jean O.
    Charpentier, G
    High-dosage treatment of a Quebec stream with Bacillus thuringiensis serovar. israelensis: efficacy against black fly larvae (Diptera, Simuliidae) and impact on nontarget insects1985Inngår i: Canadian Entomologist, ISSN 0008-347X, E-ISSN 1918-3240, Vol. 117, nr 12, 1523-1534 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A typical lake outlet of the Canadian Shield was treated for 15 min with a high dose (5.28 g/L s−1 of discharge) of Teknar®, a commercial formulation of Bacillus thuringiensis serovar. israelensis. Efficacy on Simuliidae larvae and impact on non-target aquatic insects of this stream were monitored using drift nets, counting plates, and artificial turf substrates along a 1000-m section downstream of the site of application. Compared with a 4-day pre-treatment average for 12-h sampling periods, drift of Simuliidae increased from 64 to 92 ×, with shorter peaks of 133–184 ×, 2–6 h after treatment. There was no evident drift increase in larvae of Ephemeroptera, Plecoptera, Trichoptera, Chironomidae, or dipterous pupae, but larvae of Blephariceridae (Diptera) were severely affected as their drift was increased by up to 50 × and remained high for 3 days. After 30 h the mortality of Simuliidae on counting plates ranged from 95 to 82% in the first 300 m, with detachment rates of 78.5–46.5%. Densities of non-target insect larvae were not reduced on the artificial substrates, except for 2 genera of Chironomidae (Eukiefferella and Polypedilum) which were reduced 26 to 39% of their original density. Drifting larvae of 1 chironomid genus (Phaenopsectra) also showed symptoms of toxemia by B.t.i. The main impact of the treatment was thus seen in 2 Nematocera families (Chironomidae and Blephariceridae) which were mainly exposed to B.t.i. sedimented on the bottom of the stream or attached to periphyton growing on rocks.

  • 30.
    Barclay, C J
    et al.
    Griffith University, Gold Coast, QLD, Australia.
    Widén, Cecilia
    Sveriges lantbruksuniversitet, Kristianstad.
    Efficiency of cross-bridges and mitochondria in mouse cardiac muscle2010Inngår i: Muscle biophysics: from molecules to cells / [ed] D.E. Rassier, Springer Berlin/Heidelberg, 2010, Vol. 682, 267-278 s.Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    The aim of this study was to make cellular-level measurements of the mechanical efficiency of mouse cardiac muscle and to use these measurements to determine (1) the work performed by a cross-bridge in one ATP-splitting cycle and (2) the fraction of the free energy available in metabolic substrates that is transferred by oxidative phosphorylation to free energy in ATP (i.e. mitochondrial thermodynamic efficiency). Experiments were performed using isolated left ventricular mouse papillary muscles (n = 9; studied at 27°C) and the myothermic technique. The production of work and heat was measured during and after 40 contractions at a contraction frequency of 2 Hz. Each contraction consisted of a brief isometric period followed by isovelocity shortening. Work output, heat output and enthalpy output were all independent of shortening velocity. Maximum initial mechanical efficiency (mean ± SEM) was 31.1 ± 1.3% and maximum net mechanical efficiency 16.9 ± 1.5%. It was calculated that the maximum work per cross-bridge cycle was 20 zJ, comparable to values for mouse skeletal muscle, and that mitochondrial thermodynamic efficiency was 72%. Analysis of data in the literature suggests that mitochondrial efficiency of cardiac muscle from other species is also likely to be between 70 and 80%.

  • 31.
    Beery, Thomas
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    From environmental connectedness to sustainable futures: topophilia and human affiliation with nature2015Inngår i: European Human Behaviour and Evolution Association Annual Conference, University of Helsinki, March 29-April 1, 2015, 2015, 57-58 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The objective of this study is to explore the co-evolutionary foundation for place-based human affiliation with nonhuman nature, and its potential to support sustainable development at the local level. In particular, we analyse the Topophilia Hypothesis, an expansion of the Biophilia Hypothesis which includes also non-living elements in the environment. Methods: The study represents a multidisciplinary conceptual analysis of how biological selection and cultural learning may have interacted during human evolution to promote adaptive mechanisms for human affiliation with nonhuman nature via specific place attachment. Results and Conclusions: The Biophilia Hypothesis has been one of the most important theories of human connectedness with nature, suggesting a genetically based inclination for human affiliation with the biological world. The Topophilia Hypothesis has extended the ideas of Biophilia to incorporate a broader conception of nonhuman nature and a co-evolutionary theory of genetic response and cultural learning. It also puts more emphasis on affiliation processes with the local environment. We propose that nurturing potential topophilic tendencies may be a useful method to promote sustainable development at the local level, and ultimately at the global level. Tendencies of local affiliation may also have implications for multifunctional landscape management, an important area within sustainability research, and we provide some examples of successful landscape management with a strong component of local engagement. Since human affiliation with nonhuman nature is considered an important dimension of environmental concern and support for pro-environmental attitudes, the Topophilia Hypothesis may provide a fruitful ground for a discourse within which scholars from many scientific fields, including human evolution and humanistic geography, can participate.

  • 32.
    Beery, Thomas
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    From environmental connectedness to sustainable futures: topophilia and human affiliation with nature2015Inngår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 7, nr 7, 8837-8854 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Human affiliation with nonhuman nature is an important dimension of environmental concern and support for pro-environmental attitudes. A significant theory of human connectedness with nature, the Biophilia Hypothesis, suggests that there exists a genetically based inclination for human affiliation with the biological world. Both support and challenge to the Biophilia Hypothesis are abundant in the literature of environmental psychology. One response that both challenges and builds upon the Biophilia Hypothesis is the Topophilia Hypothesis. The Topophilia Hypothesis has extended the ideas of biophilia to incorporate a broader conception of nonhuman nature and a co-evolutionary theory of genetic response and cultural learning. While the Topophilia Hypothesis is a new idea, it is built upon long-standing scholarship from humanistic geography and theories in human evolution. The Topophilia Hypothesis expands previous theory and provides a multidisciplinary consideration of how biological selection and cultural learning may have interacted during human evolution to promote adaptive mechanisms for human affiliation with nonhuman nature via specific place attachment. Support for this possible co-evolutionary foundation for place-based human affiliation with nonhuman nature is explored from multiple vantage points. We raise the question of whether this affiliation may have implications for multifunctional landscape management. Ultimately, we propose that nurturing potential topophilic tendencies may be a useful method to promote sustainable efforts at the local level with implications for the global.

  • 33.
    Beltran-Pardo, Eliana
    et al.
    Pontificia Universidad Javeriana, Instituto de Genética Humana, Bogotá.
    Jönsson, Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Wojcik, Andrzej
    Department of Genetics, Microbiology and Toxicology, Stockholm University.
    Haghdoost, Siamak
    Department of Genetics, Microbiology and Toxicology, Stockholm University.
    Bermúdez-Cruz, Rosa María
    4Departamento de Genéticas y Biología Molecular, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional - CINVESTAV, Mexico City.
    Bernal Villegas, Jaime E.
    Pontificia Universidad Javeriana, Instituto de Genética Humana, Bogotá.
    Sequence analysis of the DNA-repair gene rad51 in the tardigrades Milnesium cf. tardigradum, Hypsibius dujardini and Macrobiotus cf. harmsworthi2013Inngår i: Journal of limnology, ISSN 1129-5767, E-ISSN 1723-8633, Vol. 72, nr s1, 80-91 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tardigrades are known for being resistant to extreme conditions, including tolerance to ionising and UV radiation in both the hydratedand the dehydrated state. It is known that these factors may cause damage to DNA. It has recently been shown that single and double DNAstrand breaks occur when tardigrades are maintained for a long time in the anhydrobiotic state. This may suggest that perhaps tardigrades rely on efficient DNA repair mechanisms. Among all proteins that comprise the DNA repair system, recombinases such as RecA or Rad51 have a very important function: DNA exchange activity. This enzyme is used in the homologous recombination and allows repair of thedamaged strand using homologous non-damaged strands as a template. In this study, Rad51 induction was evaluated by western blot in Milnesium cf. tardigradum, after exposure to gamma radiation. The Rad51 protein was highly induced by radiation, when compared to the control. The rad51 genes were searched in three tardigrades: Milnesium cf. tardigradum, Hypsibius dujardini and Macrobiotus cf. harmsworthi. The gene sequences were obtained by preparing and sequencing transcriptome libraries for H. dujardini and M. cf. harmsworthi and designing rad51 degenerate primers specific for M. cf. tardigradum. Comparison of Rad51 putative proteins from tardigrades with other organisms showed that they are highly similar to the corresponding sequence from the nematode Trichinella spiralis. A structure-based sequence alignment from tardigrades and other organisms revealed that putative Rad51 predicted proteins from tardigrades contain the expected motifs for these important recombinases. In a cladogram tree based on this alignment, tardigrades tend to cluster together suggesting that they have selective differences in these genes that make them diverge between species. Predicted Rad51 structures from tardigrades were also compared with crystalline structure of Rad51 in Saccharomyces cerevisiae. These results reveal that S. cerevisiae Rad51 structure is very similar to that of the three analysed tardigrades. On the other hand the predicted structure of Rad51 from M. cf. harmsworthi and H. dujardini are closer related to each other, than each of them to that of M. cf. tardigradum.

  • 34.
    Bengtsson, Daniel
    et al.
    Linnaeus University.
    Avril, Alexis
    Linnaeus University.
    Gunnarsson, Gunnar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Söderquist, Pär
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Norevik, Gabriel
    Ottenby Bird Observatory.
    Tolf, Conny
    Linnaeus University.
    Safi, Kamran
    Max Planck Institute for Ornithology.
    Fiedler, Wolfgang
    Max Planck Institute for Ornithology.
    Wikelski, Martin
    Max Planck Institute for Ornithology.
    Olsen, Bjorn
    Uppsala University.
    Waldenstrom, Jonas
    Linnaeus University.
    Movements, home-range size and habitat selection of mallards during autumn migration2014Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 6, e100764- s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mallard (Anas platyrhynchos) is a focal species in game management, epidemiology and ornithology, but comparably little research has focused on the ecology of the migration seasons. We studied habitat use, time-budgets, home-range sizes, habitat selection, and movements based on spatial data collected with GPS devices attached to wild mallards trapped at an autumn stopover site in the Northwest European flyway. Sixteen individuals (13 males, 3 females) were followed for 15-38 days in October to December 2010. Forty-nine percent (SD = 8.4%) of the ducks' total time, and 85% of the day-time (SD = 28.3%), was spent at sheltered reefs and bays on the coast. Two ducks used ponds, rather than coast, as day-roosts instead. Mallards spent most of the night (76% of total time, SD = 15.8%) on wetlands, mainly on alvar steppe, or in various flooded areas (e.g. coastal meadows). Crop fields with maize were also selectively utilized. Movements between roosting and foraging areas mainly took place at dawn and dusk, and the home-ranges observed in our study are among the largest ever documented for mallards (mean = 6,859 ha; SD = 5,872 ha). This study provides insights into relatively unknown aspects of mallard ecology. The fact that autumn-staging migratory mallards have a well-developed diel activity pattern tightly linked to the use of specific habitats has implications for wetland management, hunting and conservation, as well as for the epidemiology of diseases shared between wildlife and domestic animals.

  • 35.
    Bengtsson, Daniel
    et al.
    Linnaeus University.
    Safi, Kamran
    Tyskland.
    Avril, Alexis
    Linnaeus University.
    Fiedler, Wolfgang
    Tyskland.
    Wikelski, Martin
    Tyskland.
    Gunnarsson, Gunnar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Tolf, Conny
    Linnaeus University.
    Olsen, Björn
    Uppsala University.
    Waldenström, Jonas
    Linnaeus University.
    Does influenza A virus infection affect movement behaviour during stopover in its wild reservoir host?2016Inngår i: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, nr 2, 150633Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The last decade has seen a surge in research on avian influenza A viruses (IAVs), in part fuelled by the emergence, spread and potential zoonotic importance of highly pathogenic virus subtypes. The mallard (Anas platyrhynchos) is the most numerous and widespread dabbling duck in the world, and one of the most important natural hosts for studying IAV transmission dynamics. In order to predict the likelihood of IAV transmission between individual ducks and to other hosts, as well as between geographical regions, it is important to understand how IAV infection affects the host. In this study, we analysed the movements of 40 mallards equipped with GPS transmitters and three-dimensional accelerometers, of which 20 were naturally infected with low pathogenic avian influenza virus (LPAIV), at a major stopover site in the Northwest European flyway. Movements differed substantially between day and night, as well as between mallards returning to the capture site and those feeding in natural habitats. However, movement patterns did not differ between LPAIV infected and uninfected birds. Hence, LPAIV infection probably does not affect mallard movements during stopover, with high possibility of virus spread along the migration route as a consequence.

  • 36. Bengtsson, Daniel
    et al.
    Waldenström, Jonas
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Gunnarsson, Gunnar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Änders rörelser kartlagda2014Inngår i: Vår fågelvärld, ISSN 0042-2649, Vol. 73, nr 5, 46-48 s.Artikkel i tidsskrift (Annet (populærvitenskap, debatt, mm))
  • 37.
    Bengtsson, Torbjörn
    et al.
    Örebro University.
    Khalaf, Atika
    Högskolan Kristianstad, Sektionen för hälsa och samhälle, Avdelningen för Hälsovetenskap II. Högskolan Kristianstad, Forskningsmiljön PRO-CARE.
    Khalaf, Hazem
    Örebro University.
    Secreted gingipains from P. gingivalis colonies exert potent immunomodulatory effects on human gingival fibroblasts2015Inngår i: Microbiological Research, ISSN 0944-5013, Vol. 178, 18-26 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Periodontal pathogens, including Porphyromonas gingivalis, can form biofilms in dental pockets and cause inflammation, which is one of the underlying mechanisms involved in the development of periodontal disease, ultimately leading to tooth loss. Although P. gingivalis is protected in the biofilm, it can still cause damage and modulate inflammatory responses from the host, through secretion of microvesicles containing proteinases. The aim of this study was to evaluate the role of cysteine proteinases in P. gingivalis colony growth and development, and subsequent immunomodulatory effects on human gingival fibroblast. By comparing the wild type W50 with its gingipain deficient strains we show that cysteine proteinases are required by P. gingivalis to form morphologically normal colonies. The lysine-specific proteinase (Kgp), but not arginine-specific proteinases (Rgps), was associated with immunomodulation. P. gingivalis with Kgp affected the viability of gingival fibroblasts and modulated host inflammatory responses, including induction of TGF-β1 and suppression of CXCL8 and IL-6 accumulation. These results suggest that secreted products from P. gingivalis, including proteinases, are able to cause damage and significantly modulate the levels of inflammatory mediators, independent of a physical host-bacterial interaction. This study provides new insight of the pathogenesis of P. gingivalis and suggests gingipains as targets for diagnosis and treatment of periodontitis.

  • 38.
    Bertolani, Roberto
    et al.
    Italien.
    Guidetti, Roberto
    Italien.
    Jönsson, K. Ingemar
    Lund University.
    Altiero, Tiziana
    Italien.
    Boschini, Deborah
    Rebecchi, Lorena
    Italien.
    Experiences with dormancy in tardigrades2004Inngår i: Journal of limnology, ISSN 1129-5767, E-ISSN 1723-8633, Vol. 63, nr Suppl. 1, 16-25 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tardigrades often colonise extreme habitats, in which they survive using both types of dormancy: quiescence and diapause. Together with nematodes and bdelloid rotifers, tardigrades are known to enter quiescence (with several forms of cryptobiosis: anhydrobiosis, cryobiosis, anoxybiosis, osmobiosis) at any stage of their life cycle, from egg to adult. Entering anhydrobiosis, tardigrades contract their body into a so-called tun, loosing most of their free and bound water (>95%), synthesizing cell protectants (e.g., trehalose, glycerol, heat shock proteins) and strongly reducing or suspending their metabolism. Our research on cryptobiosis focused on some ecological and evolutionary aspects. We evaluated: i) the long-term anhydrobiotic survival by comparing quantitative data on recovery from naturally induced desiccation in several species of tardigrades; ii) differences in survival patterns between species and populations by experimentally inducing anhydrobiosis and cryobiosis; iii) phenotypic factors affecting anhydrobiotic survival. As regards diapause, we considered encystment and eggs. Encystment involves at least the synthesis of new cuticular structures. Morphological changes during cyst formation are more complex than those involved in tun formation. We analyzed more in detail encystment processes, comparing a semiterrestrial with a limnic species. Several inter-specific differences have been identified, other than the production of two types of cysts in the semiterrestrial species. Our analysis of life history traits of a laboratory reared strain of a soil tardigrade revealed a particular hatching phenology that involved the production of both subitaneous and resting eggs. The latter need a cue to hatch (dehydration followed by re-hydration). In addition, the evolutionary meaning of dormancy in tardigrades is discussed

  • 39.
    Biederstädt, Jana
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Landskapsförändringar och deras påverkan på dagens biodiversitetsmönster hos kärlväxter i ett skånskt jordbrukslandskap2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I detta arbete studerades landskapsförändringar, i synnerhet olika typer av gräsmarkshabitat i fråga om artinnehåll och rikedom samt hur dagens diversitetsmönster har påverkats av den historiska markanvändningen. Undersökningsområdet har en area av ca 143 ha och är beläget i nordöstra Skåne. Resultatet visade att områdets areal av naturliga gräsmarker var mest omfattande kring 1783/98 och minst 1926-23. De naturliga gräsmarkernas omfattning har nästan halverats från slutet av 1700-talet till idag. Andelen betesmark som har hävdats från 1700-talets slut till 2014 utgör dock inte mer än 11 % av betesmarkernas totala areal. Väg- och dikesren uppvisade störst andel arter som var gemensamma med naturbetesmarkernas; minst var andelen i kultiverad gräsmark. Artrikedomen var minst lika hög i vägren, dikesren och skogsbryn som i naturbetesmarken medan den var lägre i kuliverad gräsmark. Artrikedomen var högst på vägrenen.

  • 40.
    Blomqvist, Maria
    et al.
    Section of Clinical Bacteriology, Department of Medical Sciences, Uppsala University.
    Christerson, Linus
    Section of Clinical Bacteriology, Department of Medical Sciences, Uppsala University.
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, Linnaeus University, Kalmar.
    Lindberg, Peter
    Department of Contaminant Research, Swedish Museum of Natural History, Stockholm.
    Helander, Björn
    Department of Zoology, Gothenburg University.
    Gunnarsson, Gunnar
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Herrman, Björn
    Section of Clinical Bacteriology, Department of Medical Sciences, Uppsala University.
    Olsen, Björn
    Section of Infectious Diseases, Department of Medical Sciences, Uppsala University.
    Chlamydia psittaci in birds of prey, Sweden2012Inngår i: Infection Ecology and Epidemiology, ISSN 2000-8686, Vol. 2, 8435- s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Chlamydia psittaci is an intracellular bacterium primarily causing respiratory diseases in birds but may also be transmitted to other animals, including humans. The prevalence of the pathogen in wild birds in Sweden is largely unknown. Methods: DNA was extracted from cloacae swabs and screened for C. psittaci by using a 23S rRNA gene PCR assay. Partial 16S rRNA and ompA gene fragments were sequence determined and phylogenies were analysed by the neighbour-joining method. Results and conclusion: The C. psittaci prevalence was 1.3% in 319 Peregrine Falcons and White-tailed Sea Eagles, vulnerable top-predators in Sweden. 16S rRNA and ompA gene analysis showed that novel Chlamydia species, as well as novel C. psittaci strains, are to be found among wild birds.

  • 41. Blomqvist, Maria
    et al.
    Christerson, Linus
    Waldenström, Jonas
    Lindberg, Peter
    Helander, Björn
    Gunnarsson, Gunnar
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Herrman, Björn
    Olsen, Björn
    Prevalence of Chlamydophila psittaci in Swedish birds2011Konferansepaper (Fagfellevurdert)
  • 42.
    Bodin, Hristina
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). SLU, Alnarp.
    Asp, Håkan
    SLU, Alnarp.
    Hultberg, Malin
    SLU, Alnarp.
    Effects of biopellets composed of microalgae and fungi on cadmium present at environmentally relevant levels in water2017Inngår i: International journal of phytoremediation, ISSN 1522-6514, E-ISSN 1549-7879, Vol. 19, nr 5, 500-504 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Removal of cadmium (Cd) present at low levels (1 µg L−1) in water was investigated using three different microorganism treatments: the microalga Chlorella vulgaris, the fungus Aspergillus niger and for the first time biopellets composed of C. vulgaris and A. niger. After 5 days, all microorganism treatments resulted in significantly lower Cd concentrations compared with the control. Biopellets treatment resulted in significantly lower pH values than other microorganism treatments, indicating that the biopellets should be investigated further for their water treatment capacity, since pH is a factor affecting the fate of numerous pollutants in water. Use of biopellets as a method to simplify harvesting of microalgae from water is also suggested.

  • 43.
    Brochet, Anne-Laure
    et al.
    CNERA Avifaune migratrice, Office National de la Chasse et de la Faune Sauvage, Arles.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Legagneux, P.
    Département de Biologie, Université Laval, Pavillon Vachon.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Gauthier-Clerc, M.
    Centre de Recherche de la Tour du Valat, Arles.
    Fritz, H.
    Université Claude Bernard Lyon 1, CNRS UMR 5558 Biométrie et Biologie Evolutive, Université de Lyon, Villeurbanne.
    Guillemain, M.
    CNERA Avifaune migratrice, Office National de la Chasse et de la Faune Sauvage, Arles.
    Is diet segregation between dabbling ducks due to food partitioning?: a review of seasonal patterns in the Western Palearctic2012Inngår i: Journal of Zoology, ISSN 0952-8369, E-ISSN 1469-7998, Vol. 286, nr 3, 171-178 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Within the paradigm of resource-limited competition-structured communities, dabbling ducks (Anas spp.) have been used as a textbook example of how morphological differences, notably bill lamellar density and body length, may allow sympatric species to partition food and hence coexist. We reviewed all accessible diet studies from the Western Palearctic for three closely related dabbling duck species, mallard (Anas platyrhynchos), pintail (A.?acuta) and teal (A.?crecca), and present a comprehensive list of the food items (invertebrates, seeds, vegetative parts of plants) ingested. To assess the circumannual perspective of niche separation, we evaluated size distribution of ingested seeds among seasons and duck species. There was a significant difference among duck species in mean size and mass of ingested seeds, as well as in diet composition, with the largest seeds consumed by the largest species (mallard) with the coarsest bill filter apparatus (lamellae), and the smallest seeds by the smallest species (teal) with the finest bill lamellae. However, no effect of season was found, suggesting consistent diet segregation among species throughout the annual cycle of ducks and over large geographical areas. We argue that the patterns of food size separation between the three species are compatible with the idea of coexistence under interspecific competition.

  • 44.
    Brodin, Anders
    et al.
    Lund University.
    Jönsson, K. Ingemar
    Lund University.
    Holmgren, Noél
    University of Skövde.
    Optimal energy allocation and behaviour in female raptorial birds during the nestling period2003Inngår i: Ecoscience, ISSN 1195-6860, Vol. 10, nr 2, 140-150 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In many raptors and owls the male is the main provider of food in the early phase of the nestling period while the female incubates the eggs and broods the young. In the nestling period the female often helps the male to feed the young, but the factors affecting whether and when she leaves the brood to hunt have not been investigated in detail. We present a dynamic state variable model that analyses female behaviour and fat storage dynamics over the nestling period. The results show that in the first half of the nestling period the female faces a conflict between the need to brood the young and the need to hunt to provision them with food. This conflict arises because the energy needs of the young peak early in the nestling period, at a time when they still cannot thermoregulate and therefore need brooding from the female. The most critical period is the second nestling week, when both female and nestling fat reserves will decrease to low levels. Large female fat reserves in the early nestling period provide a solution to this conflict and are essential for successful breeding. Stochasticity in male provisioning is thus not needed to explain why females should be fat when the eggs hatch. Under normal circumstances, the female broods during the first two weeks and leaves the young only if hunting is absolutely necessary. After the second week the energy requirements are relaxed, and whether the female assists the male in hunting or not depends on factors such as male hunting success, environmental stochasticity, and energy requirements of the young. Our model provides a framework for empirical investigations on female behaviour during breeding in raptors, owls, and other birds with marked division of labour.

  • 45.
    Bruze, Amanda
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    A comparison of nutrient reduction between activated carbon and cocout fibre in wastewater treatment2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Two batch mesocosms were created on site in Da Nang, Vietnam to reduce nutrients in wastewater from fish processing factories. The mesocosms contained either activated carbon or coconut fibre which in earlier studies has shown promising results in wastewater treatment. Three aspects of the materials were compared; Chemical content, which measured levels of COD, total-nitrogen and total-phosphorus. Rate of biofilm formation, where biofilm were measured visually and through weight. The last aspect was microbiological presence where fours species of microorganisms were cultivated. The experiment showed no obvious difference between the materials but concludes that this is an experiment that could and should be developed further.

  • 46.
    Caizergues, Alain
    et al.
    Frankrike.
    Guillemain, Matthieu
    Frankrike.
    Arzel, Céline
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Devineau, Olivier
    USA.
    Leray, Gilles
    Frankrike.
    Pilvin, Daniel
    Frankrike.
    Lepley, Michel
    Frankrike.
    Massez, Grégoire
    Frankrike.
    Schricke, Vincent
    Frankrike.
    Emigration rates and population turnover of teal Anas crecca in two major wetlands of western Europe2011Inngår i: Wildlife Biology, ISSN 0909-6396, E-ISSN 1903-220X, Vol. 17, nr 4, 373-382 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During the winter of 2003/04, we studied emigration rates of teal Anas crecca in two major wetlands: the Camargue (southern France) and the Loire estuary (western France). We derived local survival probabilities as a step in ultimately estimating emigration rates from individual mark-resighting (visual recaptures) history of birds fitted with nasal saddles. In goodness-of-fit tests of time-dependent models for local survival, we only detected the presence of transients among young females in the Loire estuary, which indicated that this category of individuals includes an ‘unstable compartment’ continuing its migratory journey further to the south. We observed low monthly local survival and high emigration rates (range: 0.01-0.81) in both areas, which suggests high turnover rates. In the Loire estuary, temporal changes in emigration rates matched the post- and pre-nuptial migration peaks (i.e. October-November and February-March). By combining local survival probabilities and count data, we derived an estimate of the ratio between the winter peak count of teals in our study areas and the minimum number of birds that actually frequented the areas over the entire wintering period (October-March). In both cases, we estimated the number of teal visiting the two wintering sites be about twice as large as the maximum number of birds counted instantaneously.

  • 47. Callaghan, Terry V.
    et al.
    Tweedie, Craig E.
    Akerman, Jonas
    Andrews, Christopher
    Bergstedt, Johan
    Butler, Malcolm G.
    Christensen, Torben R.
    Cooley, Dorothy
    Dahlberg, Ulrika
    Danby, Ryan K.
    Daniels, Fred J. A.
    de Molenaar, Johannes G.
    Dick, Jan
    Mortensen, Christian Ebbe
    Ebert-May, Diane
    Emanuelsson, Urban
    Swedish Biodiversity Centre, Uppsala.
    Eriksson, Hakan
    Hedenas, Henrik
    Henry, Greg. H. R.
    Hik, David S.
    Hobbie, John E.
    Jantze, Elin J.
    Jaspers, Cornelia
    Johansson, Cecilia
    Johansson, Margareta
    Johnson, David R.
    Johnstone, Jill F.
    Jonasson, Christer
    Kennedy, Catherine
    Kenney, Alice J.
    Keuper, Frida
    Koh, Saewan
    Krebs, Charles J.
    Lantuit, Hugues
    Lara, Mark J.
    Lin, David
    Lougheed, Vanessa L.
    Madsen, Jesper
    Matveyeva, Nadya
    McEwen, Daniel C.
    Myers-Smith, Isla H.
    Narozhniy, Yuriy K.
    Olsson, Håkan
    Pohjola, Veijo A.
    Price, Larry W.
    Riget, Frank
    Rundqvist, Sara
    Sandstroem, Anneli
    Tamstorf, Mikkel
    Van Bogaert, Rik
    Villarreal, Sandra
    Webber, Patrick J.
    Zemtsov, Valeriy A.
    Multi-Decadal Changes in Tundra Environments and Ecosystems: Synthesis of the International Polar Year-Back to the Future Project (IPY-BTF)2011Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 40, nr 6, 705-716 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Understanding the responses of tundra systems to global change has global implications. Most tundra regions lack sustained environmental monitoring and one of the only ways to document multi-decadal change is to resample historic research sites. The International Polar Year (IPY) provided a unique opportunity for such research through the Back to the Future (BTF) project (IPY project #512). This article synthesizes the results from 13 papers within this Ambio Special Issue. Abiotic changes include glacial recession in the Altai Mountains, Russia; increased snow depth and hardness, permafrost warming, and increased growing season length in sub-arctic Sweden; drying of ponds in Greenland; increased nutrient availability in Alaskan tundra ponds, and warming at most locations studied. Biotic changes ranged from relatively minor plant community change at two sites in Greenland to moderate change in the Yukon, and to dramatic increases in shrub and tree density on Herschel Island, and in sub-arctic Sweden. The population of geese tripled at one site in northeast Greenland where biomass in non-grazed plots doubled. A model parameterized using results from a BTF study forecasts substantial declines in all snowbeds and increases in shrub tundra on Niwot Ridge, Colorado over the next century. In general, results support and provide improved capacities for validating experimental manipulation, remote sensing, and modeling studies.

  • 48.
    Carlsson, Nils O L
    et al.
    Lunds universitet.
    Lacoursière, Jean O.
    Lunds universitet.
    Herbivory on aquatic vascular plants by the introduced golden apple snail (Pomacea canaliculata) in Lao PDR2005Inngår i: Biological Invasions, ISSN 1387-3547, E-ISSN 1573-1464, Vol. 7, nr 2, 233-241 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of naturally found densities of the exotic and herbivorous golden apple snail (Pomacea canaliculata) on three dominant aquatic plants – duckweed (Lemna minor), water hyacinth (Eichhornia crassipes) and morning glory (Ipomoea aquatica) – was assessed in a wetland survey and quantified in a field experiment in Laos in southeast Asia. Snail grazing reduced plant biomass, but plant species were differently affected by grazing. Duckweed had almost disappeared after 6 and water hyacinth after 21 days, whereas morning glory remained at 80% of initial biomass after 32 days. Snail growth was lowest on morning glory and, when all plant species were simultaneously presented to snails, this plant was not preferred. We suggest that the negative effect the golden apple snail had on the growth of these plant species in field enclosures is present in the natural environment as well. This new and intense herbivory could have serious negative effects on invaded freshwater ecosystems in this region.

  • 49.
    Champagnon, Jocelyn
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, Arles.
    Crochet, P. A.
    Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175 – CNRS, Montpellier.
    Kreisinger, J.
    Department of Zoology, Faculty of Science, Charles University in Prague.
    Čížková, D.
    Department of Population Biology, Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic, Brno.
    Gauthier-Clerc, M.
    Centre de Recherche de la Tour du Valat, Arles.
    Massez, G.
    Les Marais du Vigueirat, Arles.
    Söderquist, Pär
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Albrecht, T.
    Department of Zoology, Faculty of Science, Charles University in Prague.
    Guillemain, M.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, Arles.
    Assessing the genetic impact of massive restocking on wild mallard2013Inngår i: Animal Conservation, ISSN 1367-9430, E-ISSN 1469-1795, Vol. 16, nr 3, 295-305 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Captive-bred mallards Anas platyrhynchos have been released for hunting purposes at a very large scale in Europe since the mid-1970s. In spite of a potential genetic impact, the actual contribution of restocked mallards to the genome of the target population has received little attention. The genetic structure of modern wild mallards in the Camargue, Southern France, was assessed from two samples: one originating from shot birds in hunting bags and one from presumed wild ducks captured alive in a hunting-free reserve. Reference samples originated from five mallard farms, as well as from museum samples collected before the mid-1970s (i.e. before massive mallard releases started). Our results revealed that the genetic signature of wild wintering mallards has not changed significantly because museum and presumed wild samples from the Camargue hunting-free nature reserve were genetically similar, and clearly differentiated from the farm mallards. This suggests that mallard releases in the Camargue or elsewhere in France, although massive, have not actually translated into complete admixture of wild and captive genomes, most likely due to low survival of released birds once in the wild. Nevertheless, although genetic introgression of the wild population by captive-bred was contained, we found significant rates of hybridization between wild and captive-bred mallards in modern samples. This result suggests that long-term releases of captive-bred mallards, if carried on at such large scale, could compromise irreversibly the genetic structure and composition of European mallards. This work contributes to fill in the gap on the monitoring of the genetic consequences of large-scale game releases for exploitation.

  • 50.
    Champagnon, Jocelyn
    et al.
    Office National de la Chasse et de la Faune Sauvage – CNERA Avifaune Migratrice, Le Sambuc, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Office National de la Chasse et de la Faune Sauvage – CNERA Avifaune Migratrice, Le Sambuc, Arles.
    Gauthier-Clerc, Michel
    Centre de Recherche de la Tour du Valat, Le Sambuc, Arles.
    Lebreton, Jean-Dominique
    Centre d’Ecologie Fonctionnelle et Evolutive UMR 5175 - CNRS, Montpellier.
    Conspecifics can be aliens too: a review of effects of restocking practices in vertebrates2012Inngår i: Journal for Nature Conservation, ISSN 1617-1381, E-ISSN 1618-1093, Vol. 20, nr 4, 231-241 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We review the indexed scientific literature (233 papers) dealing with ‘restocking’ of vertebrates, i.e. reinforcement of wild populations by release of individuals of the same species. We found evidence that restocking may have desired beneficial effects such as: increased genetic diversity and mitigation of Allee effects in small populations; increased size or even salvation of threatened populations; increased harvest opportunities; and, redirection of harvest pressure from wild to captive-bred individuals. However, restocking may also have negative effects like changes in behaviour, morphology, and demography in recipient populations, as well as enhancement of pathogen spread. Negative genetic effects on recipient populations include homogenisation, introduction of non-native genes, and loss of local adaptation. Research thus far is strongly biased towards birds and mammals, and geographically to Europe and North America. Restocking for conservation purposes has been studied more than that for harvest management, while the latter may be of far greater importance in terms of number of released individuals. Demographic and genetic effects have been studied more than effects on behaviour, which in turn have received more attention than effects on morphology and pathogen spread. There is a general tendency for research on restocking to be fragmented taxonomically and by biological sub-disciplines. Our review demonstrates that restocking practices may and do cause significant disruptions of natural patterns in wild recipient populations. It also highlights the diversity, frequency and extent of these activities, leading us to argue that restocking is an emerging conservation and ecosystem resilience issue of global significance. Based on this review we outline monitoring and research needs for the future. We also provide guidelines to practitioners in conservation, game management, fisheries, epidemiology and other fields involved in restocking of vertebrates, who are likely to benefit from merging their perspectives and adopting a more cross-taxonomical and interdisciplinary attitude when laying out future agendas for evaluation and policy-making in this field.

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