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  • 1.
    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 Sweden2016Ingår i: Annales Zoologici Fennici, ISSN 0003-455X, E-ISSN 1797-2450, Vol. 53, nr 3-4, s. 215-227Artikel i tidskrift (Refereegranskat)
    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.

  • 2.
    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?2011Konferensbidrag (Refereegranskat)
  • 3.
    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 species2012Ingår i: Third Pan-European Duck Symposium: abstract book and programme, 2012, s. 51-Konferensbidrag (Refereegranskat)
  • 4.
    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 Norway2015Ingår i: Journal of Ornithology, ISSN 2193-7192, E-ISSN 2193-7206, Vol. 156, nr 2, s. 499-513Artikel i tidskrift (Refereegranskat)
    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.

  • 5.
    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 behaviour2007Ingår i: Book of abstracts: International Union of Game Biologists XXVIII Congress, 13-18 August, 2007, Uppsala Sweden / [ed] K. Sjöberg & T. Rooke, 2007, s. 283-Konferensbidrag (Refereegranskat)
  • 6.
    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?2006Ingår i: Integrating science and duck management: the 4th North American Duck Symposium and Workshop, 2006, s. 131-Konferensbidrag (Refereegranskat)
    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.

  • 7.
    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 perspectice2003Ingår i: Third North American duck symposium: waterfowl management and biology in the 21st century: looking back and to the future, 2003, s. 73-Konferensbidrag (Refereegranskat)
    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.

  • 8.
    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 muscle2010Ingår i: Muscle biophysics: from molecules to cells / [ed] D.E. Rassier, Springer Berlin/Heidelberg, 2010, Vol. 682, s. 267-278Kapitel i bok, del av antologi (Refereegranskat)
    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%.

  • 9.
    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 migration2014Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 9, nr 6, s. e100764-Artikel i tidskrift (Refereegranskat)
    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.

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  • 10.
    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?2016Ingår i: Royal Society Open Science, E-ISSN 2054-5703, Vol. 3, nr 2, artikel-id 150633Artikel i tidskrift (Refereegranskat)
    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.

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  • 11. 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 kartlagda2014Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 73, nr 5, s. 46-48Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 12.
    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 tardigrades2004Ingår i: Journal of limnology, ISSN 1129-5767, E-ISSN 1723-8633, Vol. 63, nr Suppl. 1, s. 16-25Artikel i tidskrift (Refereegranskat)
    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

  • 13.
    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 period2003Ingår i: Ecoscience, ISSN 1195-6860, Vol. 10, nr 2, s. 140-150Artikel i tidskrift (Refereegranskat)
    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.

  • 14.
    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 mallard2013Ingår i: Animal Conservation, ISSN 1367-9430, E-ISSN 1469-1795, Vol. 16, nr 3, s. 295-305Artikel i tidskrift (Refereegranskat)
    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.

  • 15.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Charles University, Prague.
    Janelt, Kamil
    Polen.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Chajec, Łukasz
    Polen.
    Student, Sebastian
    Polen.
    Poprawa, Izabela
    Polen.
    Ultrastructure and 3D reconstruction of the tun in Richtersius coronifer (Richters, 1903)2016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Anhydrobiosis is one of the types of cryptobiosis that is caused by lack of water (desiccation). Formation of a tun seems to be the most important morphological adaptation for entering anhydrobiotic state. During this process the tardigrade body undergo anterior-posterior contraction that causes relocation of some organs such as the pharyngeal bulb. The tun wall of Richtersius coronifer (Eutardigrada,  Macrobiotidae) was composed of multilayered cuticle and epidermis. The epidermis consisted of the single squamous epithelium whose cells were shrunken whereas  the cuticle was composed of epi-, intra- and procuticle, flocculent coat and trilaminate layer. The storage cells of desiccated specimens filled up free inner space and surrounded the internal organs (ovary, digestive system) that were contracted. All cells of the body underwent shrinking and their metabolism was arrested. The cytoplasm of all cells was electron dense but the basic morphology of cells and organelles did not differ between active and anhydrobiotic animals. The structure and the ultrastructure of the desiccated Richtersius coronifer have been described with light and confocal microscopy as well as transmission and scanning electron microscopy. 3D reconstruction of tun based on the series of semi-thin sections was prepared with IMARIS 8.2 software (Bitplane).

  • 16.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap. Charles University, Prague.
    Janelt, Kamil
    Poland.
    Student, Sebastian
    Poland.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Poprawa, Izabela
    Poland.
    A comparative ultrastructure study of storage cells in the eutardigrade Richtersius coronifer in the hydrated state and after desiccation and heating stress2018Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 13, nr 8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tardigrades represent an invertebrate phylum with no circulatory or respiratory system.Their body cavity is filled with free storage cells of the coelomocyte-type, which are responsible for important physiological functions. We report a study comparing the ultrastructure of storage cells in anhydrobiotic and hydrated specimens of the eutardigrade Richtersius coronifer. We also analysed the effect of temperature stress on storage cell structure. Firstly, we verified two types of ultrastructurally different storage cells, which differ in cellular organelle complexity, amount and content of reserve material and connection to oogenetic stage. Type I cells were found to differ ultrastructurally depending on the oogenetic stage of the animal. The main function of these cells is energy storage. Storage cells of Type I were also observed in the single male that was found among the analysed specimens. The second cell type, Type II, found only in females, represents young undifferentiated cells, possibly stem cells. The two types of cells also differ with respect to the presence of nucleolar vacuoles,which are related to oogenetic stages and to changes in nucleolic activity during oogenesis. Secondly, this study revealed that storage cells are not ultrastructurally affected by six months of desiccation or by heating following this desiccation period. However, heating of the desiccated animals (tuns) tended to reduce animal survival, indicating that longterm desiccation makes these animals more vulnerable to heat stress. We confirmed the degradative pathways during the rehydration process after desiccation and heat stress. Our study is the first to document two ultrastructurally different types of storage cells in tardigrades and reveals new perspectives for further studies of tardigrade storage cells.

  • 17.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Tjeckien.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Experimentally induced repeated anhydrobiosis in the Eutardigrade Richtersius coronifer2016Ingår i: PLOS ONE, E-ISSN 1932-6203, Vol. 11, nr 11, artikel-id e0164062Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tardigrades represent one of the main animal groups with anhydrobiotic capacity at any stage of their life cycle. The ability of tardigrades to survive repeated cycles of anhydrobiosis has rarely been studied but is of interest to understand the factors constraining anhydrobiotic survival. The main objective of this study was to investigate the patterns of survival of the eutardigrade Richtersius coronifer under repeated cycles of desiccation, and the potential effect of repeated desiccation on size, shape and number of storage cells. We also analyzed potential change in body size, gut content and frequency of mitotic storage cells. Specimens were kept under non-cultured conditions and desiccated under controlled relative humidity. After each desiccation cycle 10 specimens were selected for analysis of morphometric characteristics and mitosis. The study demonstrates that tardigrades may survive up to 6 repeated desiccations, with declining survival rates with increased numberof desiccations. We found a significantly higher proportion of animals that were unable to contract properly into a tun stage during the desiccation process at the 5th and 6th desiccations. Also total number of storage cells declined at the 5th and 6th desiccations, while no effect on storage cell size was observed. The frequency of mitotic storage cells tended to decline with higher number of desiccation cycles. Our study shows that the number of consecutive cycles of anhydrobiosis that R. coronifer may undergo is limited, with increased inability for tun formation and energetic constraints as possible causal factors.

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  • 18.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Charles University, Prague.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Mitosis in storage cells of the eutardigrade Richtersius coronifer2016Ingår i: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 178, nr 4, s. 888-896Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Although tardigrades are sometimes reported as eutelic animals, mitosis has been reported in several somatic tissues of adult eutardigrades. The occurrence of cell division in storage cells is particularly interesting in light of the important role that these cells play in the physiology of tardigrades. We present data on the occurrence of mitosis in storage cells of the eutardigrade Richtersius coronifer (Richters, 1903), and analyse mitotic cells in relation to different body characteristics, including egg development stage, moulting, gut content, body length, number and size of oocytes, and shape and size of the storage cells. Mitosis was present in ~20% of all animals, and was more frequent in juveniles than in adults. The proportion of cells with mitosis (‘mitotic index’) was low: 0.76% in juveniles and 1.47% in adults. In juveniles, none of the measured phenotypic characters had significant predictive power for mitosis, whereas in adult animals in moult or in late egg developmental or post-laying stage were more likely to have mitotic storage cells. The association with the later part of the moulting process was particularly strong. The low mitotic index and the strong association with moulting suggests that mitosis in storage cells may be connected with somatic growth rather than cell renewal, and that the purpose of cell division may relate to a need of more cells to support the enlarged body after moulting. However, the specific life cycle of tardigrades, where energy intake and depletion, egg development, and moulting is highly intertwined and synchronized, make conclusions about the functional role of mitosis in storage cells difficult, however, and more studies are needed to reveal the mechanisms inducing mitosis in these interesting cells.

  • 19.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Mitosis in storage cells of the eutardigrade Richtersius coronifer2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Tardigrades are often reported as eutelic animals, characterized by a constant cell number after maturity and growing by cell enlargement rather than by increased cell number. However, mitosis has been reported in some of the somatic tissues of adult eutardigrades, including the storage cells, and are therefore not strictly eutelic. Very few studies have investigated the presence of mitosis in tardigrades, and the occurrence of cell division in storage cells is particularly interesting in light of the important role that these cells may play in the physiology and immunology of tardigrades. We present data on the occurrence of mitosis in storage cells of the eutardigrade Richtersius coronifer and provide an analysis of storage cell mitosis in relation to different body characteristics. Specimens were examined for mitotic cells using in toto staining with aceto-lactic orcein, and the same animals were characterized with respect to egg development stage, number of oocytes, gut content, body size, and shape and size of the storage cells. Mitosis was present in ca. 30% of the animals. A large majority (3/4) of the animals with mitotic cells were found in specimens at moulting or directly after egg laying. Amount of gut content was associated with mitosis, with highest mitosis frequency (ca. 50%) in animals with an empty gut. These results for egg developmental stage (incl. moulting) and gut content are however not independent, since gut content generally decrease towards the end of the reproductive cycle. Other measured body characteristics did not influence the frequency of mitosis. In juveniles, mitotic cells were found in about half of the examined specimens. Our results suggest that proliferation of storage cells in R. coronifer is connected to the general life cycle dynamics, and provide a basis for more in depth analyses of the functional role and dynamics of storage cells in tardigrades.

  • 20.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Tjeckien.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Chajec, Lukasz
    Polen.
    Student, Sebastian
    Polen.
    Poprawa, Izabela
    Polen.
    The structure of the desiccated Richtersius coronifer (Richters, 1903)2017Ingår i: Protoplasma, ISSN 0033-183X, E-ISSN 1615-6102, Vol. 254, nr 3, s. 1367-1377Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Tun formation is an essential morphological adaptation for entering the anhydrobiotic state in tardigrades, but its internal structure has rarely been investigated. We present the structure and ultrastructure of organs and cells in desiccated Richtersius coronifer by transmission and scanning electron microscopy, confocal microscopy, and histochemical methods. A 3D reconstruction of the body organization of the tun stage is also presented. The tun formation during anhydrobiosis of tardigrades is a process of anterior-posterior body contraction, which relocates some organs such as the pharyngeal bulb. The cuticle is composed of epicuticle, intracuticle and procuticle; flocculent coat; and trilaminate layer. Moulting does not seem to restrict the tun formation, as evidenced from tardigrade tuns that were in the process of moulting. The storage cells of desiccated specimens filled up the free inner space and surrounded internal organs, such as the ovary and digestive system, which were contracted. All cells (epidermal cells, storage cells, ovary cells, cells of the digestive system) underwent shrinkage, and their cytoplasm was electron dense. Lipids and polysaccharides dominated among reserve material of storage cells, while the amount of protein was small. The basic morphology of specific cell types and organelles did not differ between active and anhydrobiotic R. coronifer.

  • 21.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap. Czech republic.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Hajer, Jaromir
    Czech republic.
    Devetter, Miroslav
    Czech Republic..
    Evaluation of extraction methods for quantitative analysis of tardigrade populations in soil and leaf litter2018Ingår i: Pedobiologia, ISSN 0031-4056, E-ISSN 1873-1511, Vol. 70, s. 1-5Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Accurate quantitative analysis of soil tardigrades depends on a relevant extraction method. Over the years, a number of different methods have been used, but the efficiency of these methods has rarely been evaluated for soil and leaf litter tardigrades. Four methods of extraction were compared in this study: the light-cooling (L-C) extractor, the high-gradient (H-G), Baermann extractor, the non-gradient (N-G) Baermann extractor and sieves.The results indicate that light and temperature are significant factors influencing tardigrade extraction. The L-C and H-G extractors were more effective than sieves for all substrate categories. These extraction methods (L-C and H-G) therefore seem to be appropriate for quantitative studies of soil and leaf litter tardigrades.

  • 22.
    Czernekova, Michaela
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH). Charles University, Prague.
    Tassidis, Helena
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Holm, Ingvar
    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).
    Primary Culture of Tardigrade Storage Cells from Richtersius coronifer Richters, 19032016Konferensbidrag (Refereegranskat)
    Abstract [en]

    Coelomocytes are macrophage-like cells in the body cavity or the coelomic spaces of many invertebrates and play major roles in their physiology and immunology. Their structure, function and diversity, however, is still poorly understood.

    Tardigrades are micrometazoans inhabiting a wide variety of environments and with an ability to survive extreme conditions. Coelomocytes (“storage cells”) represent an important part of tardigrade physiology, storing and distributing energy and possibly also having immunological functions. Few studies of tardigrade cell biology have been reported and neither primary nor continuous cell cultures have been established. Tardigrades are normally found and also cultured in an environment rich in microorganisms, some of which may even be of symbiotic value.

    In this study we have tried to establish a primary culture of storage cells in the eutardigrade Richtersius coronifer. Different cell media and concentrations of fetal bovine serum (FBS) were tested. Extracting cells from the tardigrades in an antiseptical environment is challenging since it has to be done under a microscope and contamination from the tardigrades surface is also a problem. To avoid this we tried culturing with high concentrations of antibiotics and antimycotics. We managed to keep the cells viable for up to 18 days in Grace insect medium with 10 % FBS at 20-22°C. The medium was changed every third day. 10x Antibiotic-Antimycotic and 5x of Penicillin-Streptomycin were used to minimize contamination. These concentrations reduce the bacterial abundance, but contamination with fungi was still an issue. Cell morphology evaluation was performed daily and no obvious toxic effects on the cells was observed. Cell viability and cell division were evaluated with Trypan blue staining and cell counting in a haemocytometer. The results indicate that the cells are viable and that some cell division occurs, however more studies need to be performed to confirm this. Still, this study provides the first evidence that primary cultures of storage cells from tardigrades are possible to establish, but the culturing method has to be refined to avoid contamination.

  • 23.
    Dalby, Lars
    et al.
    Department of Bioscience, Aarhus University.
    Söderquist, Pär
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Christensen, Thomas K.
    Department of Bioscience, Aarhus University.
    Clausen, Preben
    Department of Bioscience, Aarhus University.
    Einarsson, Árni
    Myvatn Research Station, Iceland.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Fox, Anthony D.
    Department of Bioscience, Aarhus University.
    Holmqvist, Niklas
    Swedish Association for Hunting and Wildlife Management, Öster Malma, Nyköping.
    Langendoen, Tom
    Wetlands International, Wageningen.
    Lehikoinen, Aleksi
    Finnish Museum of Natural History, University of Helsinki.
    Lindström, Åke
    Department of Biology,Biodiversity, Lund University.
    Lorentsen, Svein-Håkon
    Norwegian Institute for Nature Research, Trondheim.
    Nilsson, Leif
    Department of Biology, Biodiversity, Lund University.
    Pöysä, Hannu
    Finnish Game and Fisheries Research Institute, Joensuu Game and Fisheries Research.
    Sigfússon, Arnór Þ.
    Verkís, Reykjavik.
    Svenning, Jens-Christian
    Ecoinformatics & Biodiversity Group, Department of Bioscience, Aarhus University.
    The status of the Nordic populations of the Mallard (Anas platyrhynchos) in a changing world2013Ingår i: Ornis Fennica, ISSN 0030-5685, Vol. 90, nr 1, s. 2-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dabbling ducks (Anas spp.) are importantmigratory quarry species, protected as a shared resource under international legislation. However, there is a lack of sufficient high-quality data on vital demographic rates and long-term trends in numbers to judge the conservation status of many duck populations at the flyway level. In response to reported declines in the North-West European flyway population of theMallard, we compiled available data on this species in the Nordic countries up to 2010. Generally, national breeding numbers showed increasing trends, wintering abundance showed variable trends, and productivitymeasures indicated stable or increasing trends.Major knowledge gaps were identified, namely the size of hunting bags, the influence of the released Mallards and the role of short-stopping in explaining changing patterns of wintering abundance across the North-West European flyway. Numerically the Nordic breeding population appears in “good condition”, and the wintering numbers have been either stable or increasing in the last two decades. The annual number of releases needs to be determined in order to judge the sustainability of the current levels of exploitation. Overall, none of the indicators showed alarming signs for the Mallard population in the Nordic countries when considered in isolation. However, the widespread decline in wintering numbers elsewhere across North-western Europe requires urgent pan-European action.

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  • 24.
    Davis, Brian
    et al.
    USA.
    Kaminski, Rick
    USA.
    Eichholz, Mike
    USA.
    Arzel, Celine
    Finland.
    Bearhop, Stuart
    England.
    Eadie, John
    USA.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Fox, Tony
    Danmark.
    Guillemain, Matt
    Frankrike.
    Pearse, Aaron
    USA.
    Stafford, J
    USA.
    Plenary: Waterfowl habitat use and selection: knowledge gained and future science and conservation needs2013Ingår i: 6th North American Duck Symposium, Memphis, TN, January 27-31, 2013: ecology and management of North American waterfowl, 2013, s. 9-Konferensbidrag (Refereegranskat)
  • 25.
    Davranche, Aurélie
    et al.
    Frankrike.
    Arzel, Céline
    Frankrike.
    Pöysä, Hannu
    Finland.
    Nummi, Petri
    Finland.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Clausen, Preben
    Danmark.
    Pellikka, Petri
    Finland.
    Assessing habitat suitability for waterbirds along the European flyway using satellite remote sensing2012Ingår i: Third Pan-European Duck Symposium, abstract book and progamme, 2012, s. 51-Konferensbidrag (Refereegranskat)
  • 26.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Är ökande gåsstammar verkligen en skitsak?2007Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 66, nr 7, s. 11-14Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 27.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Nummi, Petri
    Finland.
    Pöysä, Hannu
    Finland.
    Sjöberg, Kjell
    SLU, Umeå.
    Hatching in dabbling ducks and emergence in Chironomids: a case of predator-prey synchrony?2011Konferensbidrag (Refereegranskat)
  • 28.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Englund, Göran
    Umeå universitet.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Arzel, Céline
    Frankrike.
    Responses of mallard ducklings towards aerial, aquatic and terrestrial predators2012Ingår i: Third Pan-European Duck Symposium: abstract book and programme, 2012, s. 17-Konferensbidrag (Refereegranskat)
  • 29.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Englund, Göran
    Department of Ecology and Environmental Science, Umeå University.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Arzél, Celine
    Section of Ecology, Department of Biology, University of Turku.
    Innate responses of mallard ducklings towards aerial, aquatic and terrestrial predators2012Ingår i: Behaviour, ISSN 0005-7959, E-ISSN 1568-539X, Vol. 149, nr 13-14, s. 1299-1317Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reproductive success in ducks is strongly influenced by predation on the breeding grounds. Ducklings are targeted by a range of terrestrial, aerial and aquatic predators, giving a strong selective advantage to individuals and broods that have effective ways to avoid predation. In experiments on naive mallard (Anas platyrhynchos) ducklings without an accompanying adult female we investigated the innate ability to identify and avoid threats at varying intensity from aerial, aquatic and terrestrial predators. Ducklings displayed increased vigilance in response to pre-recorded calls of predatory birds, representing a low level of threat. They did not react to visual and olfactory stimuli generated by motionless northern pike (Esox lucius). Neither did they show a strong response to caged American mink (Neovison vison) (visual and olfactory stimuli), although they avoided the area with the mink, indicating a certain level of recognition. High intensity threats were simulated by staging attacks from aerial (goshawk, Accipiter gentilis) and aquatic predators (northern pike). The aerial attack made ducklings dive and scatter under water, whereas the response to attack by pike was to run on the water and scatter in different directions. The lack of response to a ‘passive’ pike and the rather weak avoidance of mink indicate that olfactory cues are not as important in identifying a potential predatory threat by ducklings as are auditory cues. Visual cues appear to be of little importance unless they are combined with movement, and a clear response is only triggered when the intensity of predator threat is high. Mallard ducklings, thus, show an innate capacity to adjust anti-predator behaviour to different predator types and to threat intensity. Our study highlights the general trade-off between foraging needs and predator avoidance, but also second-order trade-offs in which innate avoidance behaviour towards one type of predator may increase predation risk from another.

  • 30.
    Eichholz, Michael W.
    et al.
    USA.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Nest site selection by Holarctic waterfowl: a multi-level review2014Ingår i: Wildfowl, ISSN 0954-6324, E-ISSN 2052-6458, nr Special Issue 4, s. 86-130Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Because of birds’ mobility, behaviour and many species’ migratory nature, they select repeatedly and spatially among habitats and have been central figures in studies of avian breeding habitat selection during the 20th and 21st centuries. The scientific literature on habitat use by breeding waterfowl has origins dating back to the writings of Charles Darwin in The Voyage of the Beagle, wherein he described the distribution and habitat differences of two species of geese on the Falkland Islands. Since that time, waterfowl ecologists have gone from descriptive studies of nest site characteristics used for planning waterfowl conservation and management to comparing nest site use in relation to potential habitat availability and determining selection for a wide array of ecological correlates. Waterfowl ecologists most recently have been investigating the adaptive significance of nest site selection by associating the latter with individual fitness and demographic measurements to assess the birds’ adaptability under environmental conditions at multiple scales of selection. While little direct assessment of 1st and 2nd order nest site selection has occurred (sensu Johnson 1980), available information is most consistent with the hypothesis that selection at these scales is driven by food availability. At the 3rd and 4th order of selection, data are consistent with hypotheses that both food availability and predator avoidance drive nest site selection, depending on the species and type of nesting aggregation. We also identify understudied areas of nest site selection important for the conservation and management of waterfowl and suggest that the large-scale influence of current anthropogenic and natural effects on the environment indicates that greater emphasis should be directed toward understanding waterfowl nest site selection at the 1st and 2nd orders of selection and how nesting habitat selection interfaces with community ecology of sympatric breeding waterfowl. Moreover, because habitat selection of prefledging waterfowl is inherently linked to breeding habitat selection, we suggest an updated review of brood habitat selection should ensue from our synthesis here.

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  • 31.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Bergand2007Övrigt (Övrigt vetenskapligt)
  • 32.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Bergand2007Övrigt (Övrigt vetenskapligt)
  • 33.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Bra häckningsår för finska vitryggar2003Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 62, nr 5, s. 30-Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 34.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Brånsjön - mer speciell än du tror!2006Ingår i: Fåglar i Västerbotten, ISSN 0348-1166, Vol. 31, nr 1, s. 14-17Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 35.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Det lönar sig att häcka tidigt och inte för trångt2012Ingår i: Fåglar i Västerbotten, ISSN 0348-1166, Vol. 37, nr 1, s. 4-9Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 36.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Ecology and natural history of the moor frog (Rana arvalis) in boreal Sweden2008Ingår i: Journal of field herpetology, nr Supplement 13, s. 179-194Artikel i tidskrift (Refereegranskat)
  • 37.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    En punktinsats för nya fågelupplevelser eller Fågelskådning på nya vägar2005Ingår i: Fåglar i Västerbotten, ISSN 0348-1166, Vol. 30, nr 3, s. 9-11Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 38.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Felbestämd korsnäbb2007Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 66, nr 3, s. 36-Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 39.
    Elmberg, Johan
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Goose poop in the park2018Ingår i: Bottom Line Health, ISSN 1092-0129, Vol. 32, nr 6Artikel i tidskrift (Refereegranskat)
  • 40.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Gräsänder klarar av klimatförändringar2012Ingår i: Fåglar i Västerbotten, ISSN 0348-1166, Vol. 37, nr 1, s. 14-18Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 41.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Hur livat är det i holken egentligen?: en smula populationsekologi för knipor och holkuppsättare2002Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 61, nr 7, s. 28-29Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 42.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Hur lärkfalken vred min sverigekarta rätt2005Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 64, nr 8, s. 20-23Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 43.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Inköpta ägg hotar gräsanden2012Ingår i: Forskning & Framsteg, ISSN 0015-7937, nr 3, s. 26-29Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [sv]

    Vad händer med inhemska arter när de vilda bestånden hela tiden fylls på med individer som är uppfödda i fångenskap och som kanske inte är anpassade till vår miljö?

  • 44.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Lever elfenbensnäbben?2013Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 72, nr 2, s. 8-Artikel i tidskrift (Övrigt vetenskapligt)
  • 45.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Nötskrikans vintervanor2012Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 71, nr 5, s. 12-Artikel i tidskrift (Övrigt vetenskapligt)
  • 46.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Punktinsats på hög nivå gav "fel" spettar2006Ingår i: Fåglar i Västerbotten, ISSN 0348-1166, Vol. 31, nr 1, s. 2-3Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 47.
    Elmberg, Johan
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Rekordmånga lyckade häckningar av vitrygg2018Ingår i: Vår fågelvärld, ISSN 0042-2649, Vol. 77, nr 1Artikel i tidskrift (Övrigt vetenskapligt)
  • 48.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Slätten tur och retur på 25 år2001Ingår i: Fåglar i Västerbotten, ISSN 0348-1166, Vol. 26, s. 54-57Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 49.
    Elmberg, Johan
    Institutet för Skoglig Zooekologi, Sveriges Lantbruksuniversitet, Umeå.
    Threats to boreal frogs1993Ingår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 22, nr 4, s. 254-255Artikel i tidskrift (Refereegranskat)
  • 50.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Varför sätta näbbsadelmärken på krickor?2004Ingår i: Ringinform, ISSN 1100-4134, Vol. 26, nr 1, s. 38-Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
1234 1 - 50 av 161
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