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  • 151.
    Felton, Adam
    et al.
    Swedish University of Agricultural Sciences, Alnarp.
    Lindbladh, Matts
    Swedish University of Agricultural Sciences, Alnarp.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Felton, Annika M.
    Swedish University of Agricultural Sciences, Alnarp.
    Andersson, Erik
    Stockholm University.
    Sekercioglu, Cagan H.
    University of Utah.
    Collingham, Yvonne
    Durham University.
    Huntley, Brian
    Durham University.
    Projecting impacts of anthropogenic climatic change on the bird communities of southern Swedish spruce monocultures: will the species poor get poorer?2014In: Ornis Fennica, ISSN 0030-5685, Vol. 91, no 1, p. 1-13Article in journal (Refereed)
    Abstract [en]

    The potential impact of climatic change on bird species’ distributions in Europe was recently modeled for several scenarios of projected late 21st century climate. The results indicate mean range shifts of hundreds of kilometres north for many of European bird species. Here we consider the implications from such distributional shifts for the bird communities of Norway spruce (Picea abies) monocultures in southern Sweden, a forest type likely to remain prevalent due to forestry, despite climate change. Our assessment led us to three key findings. First, the monocultures offer suitable habitat to only two bird species projected to extend their breeding distribution northwards into southern Sweden this century. Second, species richness was projected to decline overall, which would accentuate the depauperate nature of these stands. Third, all conifer-associated arboreal granivores and three of four conifer-associated arboreal insectivores were projected not to occur, reducing both the functional richness and functional redundancy. We discuss caveats related to our approach, including the potential for bioclimatic projections – used in this study – to be hampered by the artificial retention of dominant vegetation. We also discuss the implications of our results for avian biodiversity in what is today the most prevalent forest type in southern Sweden and in many other regions of Europe.

  • 152.
    Fox, Anthony D.
    et al.
    Danmark.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Tombre, Ingunn M.
    Norge.
    Hessel, Rebecca
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Agriculture and herbivorous waterfowl: a review of the scientific basis for improved management2017In: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 92, no 2, p. 854-877Article in journal (Refereed)
    Abstract [en]

    Swans, geese and some ducks (Anatidae) are obligate herbivores, many are important quarry species and all contribute to a variety of ecosystem services. Population growth and shifting ranges have led to increasing proximity to man and thus increasing conflicts. We review and synthesize the role of these birds as herbivores on agricultural land (cropland, rotational grassland and pasture) and other terrestrial habitats where conflict with human interests may occur. A bibliographic analysis of peer-reviewed papers (N = 359) shows that publication activity peaked in 1991-2000 in North America and 2000-2010 in Europe, and has decreased since. Taxonomic and geographical biases are obvious in research to date: Snow Goose Chen caerulescens was the most studied species (N = 98), and Canada Branta canadensis, Barnacle B. leucopsis and Brent geese B. bernicla all featured in more than 40 studies; most studies originated in northwest Europe or North America, very few have been carried out in Asia and European Russia. On the basis of nutrient/energy budgets of herbivorous waterfowl, it is evident that dense single-species crops (such as rotational grassland, early-growth cereals and root crops) and spilled grain in agricultural landscapes offer elevated energetic and nutritional intake rates of food of higher quality compared to natural or semi-natural vegetation. Hence, although affected by seasonal nutritional demands, proximity to roost, field size, disturbance levels, access to water, food depletion and snow cover, agricultural landscapes tend to offer superior foraging opportunities over natural habitats, creating potential conflict with agriculture. Herbivorous waterfowl select for high protein, soluble carbohydrate and water content, high digestibility as well as low fibre and phenolic compounds, but intake rates from grazing varied with goose body and bill morphology, creating species-specific loci for conflict. Crop damage by trampling and puddling has not been demonstrated convincingly, nor do waterfowl faeces deter grazing stock, but where consumption of crops evidently reduces yields this causes conflict with farmers. Studies show that it is difficult and expensive to assess the precise impacts of waterfowl feeding on yield loss because of other sources of variation. However, less damage has been documented from winter grazing compared to spring grazing and yield loss after spring grazing on grassland appears more pronounced than losses on cereal fields. Although yield losses at national scales are trivial, individual farmers in areas of greatest waterfowl feeding concentrations suffer disproportionately, necessitating improved solutions to conflict. Accordingly, we review the efficacy of population management, disturbance, provision of alternative feeding areas, compensation and large-scale stakeholder involvement and co-management as options for resolving conflict based on the existing literature and present a framework of management advice for the future. We conclude with an assessment of the research needs for the immediate future to inform policy development, improve management of waterfowl populations and reduce conflict with agriculture.

  • 153.
    Green, Andy J.
    et al.
    Estación Biológica de Doñana, CSIC, Sevilla.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Ecosystem services provided by waterbirds2014In: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 89, no 1, p. 105-122Article in journal (Refereed)
    Abstract [en]

    Ecosystem services are ecosystem processes that directly or indirectly benefit human well-being. There has been much recent literature identifying different services and the communities and species that provide them. This is a vital first step towards management and maintenance of these services. In this review, we specifically address the waterbirds, which play key functional roles in many aquatic ecosystems, including as predators, herbivores and vectors of seeds, invertebrates and nutrients, although these roles have often been overlooked. Waterbirds can maintain the diversity of other organisms, control pests, be effective bioindicators of ecological conditions, and act as sentinels of potential disease outbreaks. They also provide important provisioning (meat, feathers, eggs, etc.) and cultural services to both indigenous and westernized societies. We identify key gaps in the understanding of ecosystem services provided by waterbirds and areas for future research required to clarify their functional role in ecosystems and the services they provide. We consider how the economic value of these services could be calculated, giving some examples. Such valuation will provide powerful arguments for waterbird conservation.

  • 154.
    Guillemain, M.
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Elmberg, Johan
    Kristianstad University, Department of Mathematics and Science.
    Arzel, C.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Johnson, A. R.
    Station Biologique de la Tour du Valat, le Sambuc, Arles.
    Simon, G.
    Station Biologique de la Tour du Valat, le Sambuc, Arles.
    The income–capital breeding dichotomy revisited: late winter body condition is related to breeding success in an income breeder2008In: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 150, no 1, p. 172-176Article in journal (Refereed)
  • 155.
    Guillemain, Matthieu
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Arzel, Céline
    Kristianstad University, Department of Mathematics and Science.
    Legagneux, Pierre
    Centre d'Etudes Biologiques de Chizé - CNRS UPR 1934, Beauvoir-sur-Niort.
    Elmberg, Johan
    Kristianstad University, Department of Mathematics and Science.
    Fritz, Hervé
    Centre d'Etudes Biologiques de Chizé - CNRS UPR 1934, Beauvoir-sur-Niort.
    Lepley, Michel
    Station Biologique de la Tour du Valat, Le Sambuc, Arles.
    Pin, Christophe
    Les Marais du Vigueirat, Mas Thibert, Arles.
    Arnaud, Antoine
    Station Biologique de la Tour du Valat, Le Sambuc, Arles.
    Massez, Grégoire
    Les Marais du Vigueirat, Mas Thibert, Arles.
    Predation risk constrains the plasticity of foraging behaviour in teals, Anas crecca: a flyway-level circumannual approach2007In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 73, no 5, p. 845-854Article in journal (Refereed)
    Abstract [en]

    The trade-off foragers make between predation risk and feeding efficiency is readily studied in dabbling ducks, which have stereotyped feeding methods, some of which prevent predator detection while others do not. Teals forage mostly with only the bill submerged (eyes above the water surface) in winter, but use a broader foraging repertoire in summer. Given the different environments used by teals over the year, it is likely that such a shift is due to changes in diet, but it may also be caused by differences in predation risk between habitats. However, neither predation risk nor teal behaviour has been studied with consistent methods around the year or throughout any of its flyways. Covering wintering, spring-staging, breeding and moulting sites, we combined focal observations of teals and predator flyover data from seven regions ranging from southern France to northern Sweden. Although not apparent at the scale of days within sites, teals indeed relied more on shallow foraging where predation risk was higher, i.e. at wintering sites. Average foraging depth increased gradually from September to August, i.e. from wintering to breeding sites. Foraging bout length of deeply foraging teals did not decrease over the year, suggesting that it is through selection of foraging technique, rather than by the balance between foraging and interruptions, that birds adjust to predation risk. This study highlights behavioural plasticity in response to contrasting selection regimes within a flyway, in dabbling ducks as well as long-distance migrants in general.

  • 156.
    Guillemain, Matthieu
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice , La Tour du Valat, Le Sambuc, Arles.
    Arzel, Céline
    Kristianstad University, Department of Mathematics and Science.
    Legagneux, Pierre
    Centre d’Etudes Biologiques de Chizé, CNRS UPR 1934, Beauvoir sur Niort.
    Elmberg, Johan
    Kristianstad University, Department of Mathematics and Science.
    Fritz, Hervé
    Centre d’Etudes Biologiques de Chizé, CNRS UPR 1934, Beauvoir sur Niort.
    Lepley, Michel
    Station Biologique de la Tour du Valat, Le Sambuc, Arles.
    Pin, Christophe
    Station Biologique de la Tour du Valat, Le Sambuc, Arles.
    Arnaud, Antoine
    Station Biologique de la Tour du Valat, Le Sambuc, Arles.
    Massez, Grégoire
    Les Marais du Vigueirat, Mas Thibert, Arles.
    Risky foraging leads to cost-free mate guarding in male teal Anas crecca2007In: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 148, no 2, p. 251-254Article in journal (Refereed)
    Abstract [en]

    Mate guarding by males is common in species with long-lasting pair bonds. We tested if the need to guard females affected foraging depth in male teal (Anas crecca), and if they were more vigilant than females when foraging with submerged eyes (preventing monitoring of competing males and predators). These predictions were not supported, suggesting that foraging depth selection is primarily driven by other factors, presumably food related. A likely reason why deeply foraging males did not increase vigilance is that 37.5% of the foraging time was already dedicated to it. The apparent lack of guarding costs in foraging male teal may explain why such small ducks can maintain pair bonds for up to 7 months.

  • 157.
    Guillemain, Matthieu
    et al.
    Frankrike.
    Champagnon, Jocelyn
    Frankrike.
    Pernollet, Claire A.
    Frankrike.
    Devineau, Olivier
    Norge.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Cavallo, François
    Frankrike.
    Massez, Grégoire
    Frankrike.
    Combined effects of climate change and fluctuating habitat quality on the distribution of ducks in southern Europe2016In: 7th North American Duck Symposium: waterfowl ecology and adaptive management, 2016Conference paper (Refereed)
    Abstract [en]

    Changes in waterfowl ranges over the last decades are increasingly reported, both in North America and in Europe. The relative importance of different winter quarters may fluctuate under the influence of changing local habitat conditions, as well as according to general trends caused by global climate change. Several European duck species have shifted their winter range to the North-East, i.e. the distance between breeding and wintering grounds was reduced, in a pattern consistent with a global temperature increase. In northern countries, this could also indicate an increasing proportion of sedentary birds. We compared the geographic distribution of recoveries of bands fitted to Mallard (Anas platyrhynchos) and Common Teal (A. crecca) in Camargue, southern France, over the last 60 years. Close to 75,000 ducks were banded since the early 1950s. Band recoveries occurred to a much greater extent in the Camargue area than in other parts of the flyways during the last decade compared to earlier years: as opposed to earlier studies, recoveries of Camargue-ringed ducks are increasingly made to the South-West. For migratory Teal, this indicates an increased faithfulness to the Camargue winter quarter. For Mallard, though, some birds may have become around-the-year residents: while the distance from banding site to recovery location was >400 km between the 1950s and 1970s, it is <75 km nowadays. Several hypotheses are proposed to explain these changes in European duck distributions. Survival analyses are also carried out, which help assessing whether changes in geographic distribution have also translated into altered demographic rates. Besides the overriding effects of climate change in the long-term, the present results suggest that local habitat management practices still have the potential to greatly affect the distribution of waterfowl.

  • 158.
    Guillemain, Matthieu
    et al.
    Frankrike.
    Champagnon, Jocelyn
    Frankrike.
    Pernollet, Claire A.
    Frankrike.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Mouronval, Jean-Baptiste
    Frankrike.
    Massez, Grégoire
    Frankrike.
    Still worth the travel?: changes in Camargue teal migration patterns, body condition and demographic parameters over 60 years2015In: 4th Pan-European Duck Symposium, Hangö, Finland, 8-11/4 2015, 2015, p. 28-Conference paper (Refereed)
    Abstract [en]

    Climate and habitat changes linked with human activities have profoundly modified the road maps of waterfowl across their geographic ranges. If new breeding grounds open to the North, traditional wintering sites may gradually get deserted by birds short-stopping during the autumn and shifting their nonbreeding distribution. More than 60,000 ringing data were collected from wintering Teal (Anas crecca) in the area from the early 1950s to the beginning of the 2010s. Migration patterns have changed with birds now arriving much earlier, and overall population movements being much reduced during winter. The body condition of Camargue-wintering Teal has improved dramatically compared to the pre-1970 era, which could be a cause and/or a consequence of such changes in migration processes: Teal may arrive increasingly early in the year because artificial summer flooding of wetlands and baiting now provide suitable habitat and abundant accessible food. In turn, reduced movements linked with greater residency in the Camargue would impose smaller use of the body reserves. The comparison of Teal turnover and survival rates during historical (1950s- 1970s) and modern (post-2002) years provides some insight as to whether the situation has gradually improved for these birds. Conversely, the sustained use of the Camargue could simply reflect these birds being lured by artificially increased availability of food, which they would use at the expense of their survival rate, hence with no positive consequences in terms of population dynamics.

  • 159.
    Guillemain, Matthieu
    et al.
    Frankrike.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    The teal2014Book (Refereed)
    Abstract [en]

    Small, noisy and colourful, the Teal is a familiar duck throughout the wetlands and waterways Europe and Asia. Once hunted extensively for the pot, its numbers have recovered and it is now one of our commonest species of waterfowl.

    A flagship species for wetland conservation, the Teal is also an excellent model species for ecological research, and this forms the spine of this new Poyser monograph.

    The Teal looks at distribution and trends in numbers, foraging ecology, breeding behaviour), population dynamics, management and conservation of teal, looking at both the Eurasian Common Teal and its North American equivalent, the Green-winged Teal (which until relatively recently was considered to be the same species). The book provides a scientifically robust account on which wetland managers, research scientists and the ornithological community may rely, with wider implicatons for the conservation and management of other waterfowl, and for ecological research in general.

  • 160.
    Guillemain, Matthieu
    et al.
    Frankrike.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Arzel, Céline
    Finland.
    Johnson, AR
    Simon, G
    Linking wintering and breeding grounds: good winter conditions are associated with higher breeding success in Teal Anas crecca2007In: Book of abstracts: International Union of Game Biologists XXVIII Congress, 13-18 August, 2007 / [ed] K.I. Sjöberg & T. Rooke, 2007, p. 285-Conference paper (Refereed)
  • 161.
    Guillemain, Matthieu
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice La Tour du Valat, Le Sambuc, Arles.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Gauthier-Clerc, Michel
    Centre de Recherche de la Tour du Valat Le Sambuc, Arles.
    Massez, Grégoire
    Les Marais du Vigueirat Mas Thibert, Arles .
    Hearn, Richard
    Wildfowl & Wetlands Trust, Slimbridge, Gloucester.
    Champagnon, Jocelyn
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice La Tour du Valat, Le Sambuc, Arles .
    Simon, Géraldine
    Centre de Recherche de la Tour du Valat Le Sambuc, Arles .
    Wintering French mallard and teal are heavier and in better body condition than 30 years ago: effects of a changing environment?2010In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 39, no 2, p. 170-180Article in journal (Refereed)
    Abstract [en]

    Animal populations are exposed to large-scale anthropogenic impact from e.g. climate change, habitat alteration and supplemental stocking. All of these may affect body condition in wintering dabbling ducks, which in turn may affect an individual's survival and reproductive success. The aim of this study was to assess whether there have been morphometric changes in Mallard (Anas platyrhynchos) and Teal (Anas crecca) over the last 30 years at a major wintering site. Body mass and condition increased from the 1950s-1960s to the 2000s in both species. The increase in body mass amounted to as much as 11.7%, with no corresponding change in body size. Improved body condition was maintained from early to mid-winter, but then converged with historical values for late winter. Our interpretation is that increasingly benign ambient winter conditions permit ducks to maintain better energetic "safety margins" throughout winter, and that converging spring departure values may be related to evolutionary flight energetic optima. The observed changes are consistent with large-scale climate amelioration and local/regional habitat improvement (both anthropogenic).

  • 162.
    Guillemain, Matthieu
    et al.
    Frankrike.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man & Biosphere Health (MABH).
    Pernollet, Claire A.
    Frankrike.
    Arzel, Celine
    Finland.
    Eadie, John M.
    USA.
    Agent-based modeling may help to merge research traditions in foraging ecology in Europe and North America2017In: Wildlife Society bulletin, ISSN 0091-7648, E-ISSN 1938-5463, Vol. 41, no 1, p. 170-176Article in journal (Refereed)
    Abstract [en]

    Although ducks have long been popular research subjects in both North America and Europe, geographical divergences in research orientation have developed during the past several decades for studying foraging ecology. In North America, foraging studies largely focused on the population level with an emphasis on foraging energetics aimed at improving waterfowl production through increased carrying capacity of wetlands in breeding areas, an approach later expanded to nonbreeding grounds. In Europe, studies have instead focused on inter-individual differences in behavior of foraging ducks, with an emphasis on individual efficiency (e.g., methods, intake rate, patch choice) within the framework of optimal foraging theory. We suggest that agent-based models (also termed individual-based behavior models), which aim to predict habitat use from the heterogeneous behavior of different individual agents, can help to unify these approaches and would benefit considerably from increased collaboration and integration of the approaches of both North American and European researchers.

  • 163.
    Guillemain, Matthieu
    et al.
    Frankrike.
    Pernollet, Claire A.
    Frankrike.
    Arzel, Céline
    Finland.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Eadie, John
    USA.
    Foraging, nutrition, and energetics of waterfowl: a European perspective2016In: 7th North American Duck Symposium: waterfowl ecology and adaptive management, 2016Conference paper (Refereed)
    Abstract [en]

    Much attention has historically been devoted to feeding ecology of waterfowl, providing an extensive research record for Europe and North America alike. However, research in this field has gradually followed different paths on the two continents. American scientists have adopted a more applied perspective, often aiming at assessing the extent to which food requirements of waterfowl can be fulfilled in different habitats, and how management of these can increase carrying capacity. As opposed to this "energetic" approach, European scientists have rather framed their studies in a "behavioral" perspective, using waterfowl as model species for more theoretical approaches to foraging ecology. Consequently, while North American research has most often been carried out at the scale of waterfowl populations, the individual bird has more frequently been the scale of study in Europe. We present three examples of such European studies: first, a detailed analysis of the trade-offs made by dabbling ducks between foraging and anti-predator vigilance, leading to divergent strategies to face gradual food depletion during the winter. Second, we do a flyway-scale analysis of duck foraging needs and behavior, from Mediterranean wintering grounds to breeding sites in the Boreal, and point out the main hurdles faced by these birds across their annual cycle. Such detailed European studies can provide useful parameter values to fuel modern agent-based models of habitat use and carrying capacity developed in North America, hence cross-fertilizing the approaches on the two continents. This is exactly what our third example is about; namely adapting the SWAMP model developed in California to better understand and predict the use of harvested rice fields by wintering ducks in southern France.

  • 164. Guillmain, Matthieu
    et al.
    Elmberg, Johan
    Kristianstad University, School of Health and Society.
    Gauthier-Clerc, Michel
    Massez, Grégoire
    Hearn, Richard
    Simon, Géraldine
    Champagnon, Jocelyn
    Wintering dabbling ducks have become heavier: an effect of global warming or intensified game management practices?2009In: Abstracts, 2nd Pan-European Duck Symposium, 2009, p. 52-Conference paper (Refereed)
  • 165.
    Gunnarson, Gunnar
    et al.
    Kristianstad University, Department of Mathematics and Science.
    Elmberg, Johan
    Kristianstad University, Department of Mathematics and Science.
    Sjöberg, Kjell
    Department of Animal Ecology, Swedish University of Agricultural Sciences.
    Pöysä, Hannu
    Finnish Game and Fisheries Research Institute, Joensuu Game and Fisheries Research.
    Nummi, Petri
    Department of Applied Biology, University of Helsinki.
    Experimental evidence for density-dependent survival in mallard Anas platyrhynchos ducklings2006In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 149, no 2, p. 203-213Article in journal (Refereed)
    Abstract [en]

    It is unresolved to what extent waterfowl populations are regulated by density-dependent processes. By doing a 2-year crossover perturbation experiment on ten oligotrophic boreal lakes we addressed the hypothesis that breeding output is density dependent. Wing-clipped mallard (Anas platyrhynchos) hens were introduced with their own brood and then monitored for 24 days. Predicted responses were that per capita duckling and hen survival would be lower in high-density than in low-density treatments. Survival was evaluated by model fitting in program MARK. Density, year, and lake were used as main effects, while day after introduction, a weather harshness index, and presence of hens were covariates. Daily survival in ducklings was lower in the high-density treatment, but this effect was year dependent. The highest-ranking model for duckling survival also included a positive effect of duckling age and presence of hens, and a negative effect of harsh weather. Density did not affect female survival although there was a prominent year effect. The highest-ranking model for female survival also included negative effects of day after introduction and harsh weather. This is the first study to report density-dependent survival in experimentally introduced ducklings in a natural setting. Implications for population dynamics and management of harvested populations are far-reaching if such regulation occurs in some years, but not in others.

  • 166.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Department of Mathematics and Science.
    Elmberg, Johan
    Kristianstad University, Department of Mathematics and Science.
    Density-dependent nest predation: an experiment with simulated Mallard nests in contrasting landscapes2008In: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 150, no 2, p. 259-269Article in journal (Refereed)
    Abstract [en]

    Breeding success is a key element of animal population dynamics. In many taxa including birds, nest success, or the proportion of laid clutches that actually hatch, is mainly determined by predation. Previous research gives an inconsistent picture of the prevalence of density-dependent nest predation and one reason for this is the general lack of well-designed replicated experiments. Using simulated Mallard Anas platyrhynchos nests and a crossover design for 20 lakes in the nemoral and boreal biotic zones, we tested the predictions that nest survival is negatively density-dependent and that nest predation is higher in agricultural than in forested landscapes. Study day and daily abundance of waterfowl, other waterbirds, as well as avian predators were included as covariates in the analysis. Model fitting in program mark revealed a general negative effect of nest density on nest survival. In addition, nest survival rate was higher at forest lakes than at lakes in agricultural landscapes, irrespective of nest density. The only covariate producing model improvement was study day; older nests had higher survival rates than recently initiated ones. This is the first replicated lake-level experimental study showing that nest predation is density-dependent in waterfowl. The pattern was consistent between landscape types, implying that density-dependent nest predation may affect habitat choice and population dynamics over large parts of the Mallard's range.

  • 167.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Density-dependent nest predation in dabbling ducks2002Conference paper (Refereed)
  • 168.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Predation regulates the survival of mallard nests as revealed by an experiment in two landscape types2006Conference paper (Refereed)
    Abstract [en]

    Ecological theory frequently postulates that most animal species are subject to density-dependent mechanisms in some stage of the year or life. However, few avian studies have succeeded to give evidence for regulatory mechanisms by replicated experiments in natural habitats. Breeding success is to a great extent determined by conditions during the nesting period and the major cause of nesting failure is nest predation. In addition, predators may possibly regulate fluctuating populations and to test the hypothesis that nest survival is negatively density-dependent we conducted an experiment with manipulated densities of semi-natural Mallard nests and adult pairs using 32 small to medium sized lakes (~3-5 hectares) in southern Sweden during two nesting seasons (2003-2004). Predicting that predation rates are higher in open compared to more vegetated habitats, half of the lakes were in agricultural and the other half in forest landscapes. Using real Mallard eggs, nests were constructed in two densities; either 2 nests per lake (low density) or 8 nests per lake (high density). Model fitting in program MARK revealed that nest survival was negatively affected by nest density but not by pair density. Further, predation rates were much higher in agricultural landscapes than in forested. The effects of nest density and habitat were consistent in the two years. Covariates added to the model matrix revealed a negative effect of other waterfowl present on the lakes and a positive effect of study day. However, the number of avian predators observed at the lakes did not affect survival. Our experiment is the first to demonstrate density-dependent nest predation in Mallard. The consistency of the density effect between years and habitats shows that regulatory mechanisms may be truly significant for Mallard, possibly affecting population dynamics of the species.

  • 169.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Dessborn, Lisa
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Jonzén, Niclas
    Department of Theoretical Ecology, Lund University.
    Pöysä, Hannu
    Finnish Game and Fisheries Research Institute, Joensuu.
    Valkama, Jari
    Finnish Museum of Natural History, Helsinki.
    Survival estimates, mortality patterns, and population growth of Fennoscandian mallards Anas platyrhynchos2008In: Annales Zoologici Fennici, ISSN 0003-455X, E-ISSN 1797-2450, Vol. 45, no 6, p. 483-495Article in journal (Refereed)
    Abstract [en]

    Long-term mallard capture-recapture data from Sweden and Finland were analyzed to describe temporal mortality patterns and reasons. We used program MARK and Seber models to estimate annual survival (S) and recovery (r) rates. Survival rates were used in a Monte Carlo simulation to evaluate the correspondence between observed and predicted annual population sizes of a Finnish sub-population. About 90% of recovered birds died from hunting. Most recoveries were from the hunting season, and more males than females were shot. Predation was the most common cause of natural mortality. Finnish capture-recapture data fitted best the global model in which survival and recovery vary with age and sex. Annual survival and recovery rates for adult and juvenile males and females were overlapping, ranging from 0.46 to 0.90 (survival) and 0.07 to 0.17 (recovery), whereas pulli had lower survival rates (0.21-0.42). Pulli that were successfully sexed at the time of ringing had higher recovery rates (female pulli: 0.23; male pulli: 0.32) than juveniles and adults. Density-dependent fledgling production was detected in the Finnish sub-population and was accounted for in the Monte Carlo simulation, which estimated predicted breeding population size quite well, although one of the observed annual values (2003) fell outside the 95% confidence limits.

  • 170.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Pöysä, Hannu
    Joensuu Game and Fisheries Research, Finnish Game and Fisheries Research Institute.
    Sjöberg, Kjell
    Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, Umeå.
    Dessborn, Lisa
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Arzel, Céline
    Section of Ecology, Department of Biology, Turku University.
    Density dependence in ducks: a review of the evidence2013In: European Journal of Wildlife Research, ISSN 1612-4642, E-ISSN 1439-0574, Vol. 59, no 3, p. 305-321Article in journal (Refereed)
    Abstract [en]

    Density dependence (DD) is a central concept in population ecology and in the management of harvested populations. For example, DD underpins the idea of additive versus compensatory mortality and is a tenet in the paradigm of resource limitation and regulation. Yet the prevalence and importance of DD remains disputed in most organisms, including ducks, which are focal in game management, conservation and zoonotic diseases. Based on 154 data entries from 54 studies in the peer-reviewed literature, we here synthesize and evaluate the prevalence of DD in breeding ducks in relation to (1) species and guild (dabbling versus diving ducks), (2) stage in the breeding cycle (nesting, duckling, recruitment) or, alternatively, in terms of population dynamics, (3) study type (descriptive/nonmanipulative versus experimental), (4) continent (Europe versus North America), (5) spatial level (wetland, landscape, regional, continental) and (6) biome (tundra, boreal, nemoral, prairie, mediterranean). One conclusion from this review is that it is difficult to find general patterns about the prevalence of DD unless data are broken down to subsets, for example, to stage or spatial level. With respect to stage, DD effects occur at all stages of the breeding cycle. During the nesting and duckling stages, the frequency of cases detecting versus not detecting DD is roughly the same. However, in cases referring to the recruitment stage, i.e. to survival of fledged ducks until 1 year old at the most, DD was the rule, suggesting that DD processes may operate mainly outside the breeding season. Further subdivision of data shows that spatial scale is important to the prevalence of DD in nesting ducks—rare on the wetland level and more common on higher spatial levels. In studies of population dynamics (i.e. based on time series data only), DD was more often found in diving than in dabbling ducks. This corroborates previous suggestions that dabbling ducks largely should be considered as r-selected species, in contrast to more K-selected diving ducks, which start to reproduce at an older age and often breed in more stable wetland environments where resources may be easier to track and populations thus often are closer to carrying capacity. However, the picture of DD in ducks is far from complete, and knowledge gaps for future studies to address include: (a) data from Russia, which holds a large part of the breeding ducks in the Northern hemisphere, (b) experimental studies on more species to separate density-dependent factors from other drivers of population change and to tease apart spatial and temporal interactions in the underlying processes, (c) time series analyses addressing population dynamics, especially from outside North America, (d) studies relating duck numbers to limiting resources, which arguably is the most relevant measure of density, (e) the timing of DD processes in relation to harvest and natural mortality.

  • 171.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Sjöberg, Kjell
    SLU.
    Pöysä, Hannu
    Finland.
    Nummi, Petri
    Finland.
    Experimental evidence for density-dependent breeding success in mallards2005Conference paper (Refereed)
    Abstract [en]

    It is unresolved to what extent waterfowl populations are regulated by density-dependent pro cesses. By doing a 2-year crossover perturbation exper iment on ten oligotrophic boreal lakes we addressed the hypothesis that breeding output is density depen dent. Wing-clipped mallard (Anas platyrhynchos) hens were introduced with their own brood and then moni tored for 24 days. Predicted responses were that per capita duckling and hen survival would be lower in high-density than in low-density treatments. Survival was evaluated by model fitting in program MARK. Density, year, and lake were used as main effects, while day after introduction, a weather harshness index, and presence of hens were covariates. Daily survival in ducklings was lower in the high-density treatment, but this effect was year dependent. The highest-ranking model for duckling survival also included a positive effect of duckling age and presence of hens, and a nega tive effect of harsh weather. Density did not affect female survival although there was a prominent year effect. The highest-ranking model for female survival also included negative effects of day after introduction and harsh weather. This is the first study to report den sity-dependent survival in experimentally introduced ducklings in a natural setting. Implications for population dynamics and management of harvested populations are far-reaching if such regulation occurs in some years, but not in others.

  • 172.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Sjöberg, Kjell
    SLU.
    Pöysä, Hannu
    Finland.
    Nummi, Petri
    Finland.
    Food limits survival in breeding mallards2003In: Integrating wildlife with people, 10th International Perdix Symposium, Braga, Portugal, September 1st-6th 2003: abstracts and contributing authors, Braga: International Union of Game Biologists , 2003Conference paper (Refereed)
  • 173.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Sjöberg, Kjell
    SLU.
    Pöysä, Hannu
    Finland.
    Nummi, Petri
    Finland.
    Food limits survival of breeding boreal mallards Anas platyrhynchos2003Conference paper (Refereed)
    Abstract [en]

    During the breeding period dabbling ducks (Anas sp.), and especially newly hatched ducklings, face heavy mortality. The reasons are not clear, but suggested factors contributing are scarce food, predation, chilling and disease. We highlighted the question why many of the boreal lakes in Scandinavia are without breeding ducks and why mortality is considerable during brood period. In an experimental study in 2002 we hypothesized food being a major factor deciding duck survival during breeding. One wing-clipped hen mallard with her own newly hatched brood (10 ducklings) was introduced onto each of 10 lakes. Food was added ad libitum at 5 of these lakes (experimental lakes), whereas the other five lakes (controls) did not get any extra food added. Survival of hens, broods as well as each individual duckling was monitored regularly until 24 days after introduction. At all three levels (i.e. duckling, brood and adult), survival was significantly higher on lakes with food added than on control lakes, although the difference was most pronounced on the duckling level. Direct consequences (i.e. dying from starvation) as well as indirect (e.g. undernourished individuals being more easily taken by predators) may both explain this pattern. Our results clearly show that food is a major limiting factor on mallard survival in this environment. Also, our results may explain why many boreal lakes in Scandinavia do not have any breeding waterfowl at all. It seems likely that such lakes are too poor to raise broods and even to sustain adults.

  • 174.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Department of Mathematics and Science.
    Elmberg, Johan
    Kristianstad University, Department of Mathematics and Science.
    Sjöberg, Kjell
    Department of Animal Ecology, Swedish University of Agricultural Sciences, Umeå.
    Pöysä, Hannu
    Finnish Game and Fisheries Research Institute, Joensuu Game and Fisheries Research.
    Nummi, Petri
    Department of Applied Biology, University of Helsinki.
    Why are there so many empty lakes?: food limits survival of mallard ducklings2004In: Canadian Journal of Zoology, ISSN 0008-4301, E-ISSN 1480-3283, Vol. 82, no 11, p. 1698-1703Article in journal (Refereed)
    Abstract [en]

    Food is an important factor affecting survival in many bird species, but this relationship has rarely been explored experimentally with respect to reproductive output of precocial birds. In a field experiment we tested the hypothesis that food abundance limits reproductive output in breeding dabbling ducks. Onto 10 oligotrophic lakes in northern Sweden we introduced one wing-clipped female mallard (Anas platyrhynchos L., 1758) and a brood of 10 newly hatched ducklings, and survival was monitored for 24 days. Food was added ad libitum at five of the lakes, but not at the other five. Duckling survival was best modelled to include a treatment effect, with higher survival on lakes with food added, and a negative effect of harsh weather. As expected, duckling survival increased nonlinearly with age. Only one female remained on control lakes after 24 days, whereas four remained on lakes with food added. This is the first experimental demonstration that food may limit survival and reproductive output in breeding precocial birds. We argue that food limitation may be one reason why duckling mortality is high and why many lakes throughout the Holarctic have no breeding dabbling ducks.

  • 175.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Trends in body mass of ducks over time: the hypotheses in Guillemain et al. revisited2011In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 40, no 3, p. 338-340Article in journal (Refereed)
  • 176.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Teacher Education.
    Elmberg, Johan
    Kristianstad University, School of Teacher Education.
    Waldenström, Jonas
    Olsen, Björn
    Änderna, influensan och jakten2010In: Svensk jakt: Svenska jägareförbundets tidskrift, ISSN 0039-6583, no 6, p. 74-75Article in journal (Other (popular science, discussion, etc.))
  • 177.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Teacher Education.
    Jourdain, Elsa
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Helander, Björn
    Department of Contaminant Research, Swedish Museum of Natural History, Stockholm.
    Lindberg, Peter
    Department of Zoology, University of Gothenburg.
    Elmberg, Johan
    Kristianstad University, School of Teacher Education.
    Latorre-Margalef, Neus
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Olsen, Björn
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Zero prevalence of influenza A virus in two raptor species by standard screening2010In: Vector Borne and Zoonotic Diseases, ISSN 1530-3667, E-ISSN 1557-7759, Vol. 10, no 4, p. 387-390Article in journal (Refereed)
    Abstract [en]

    Disease can have severe impact on animal populations, especially in rare species. Baseline data for atypical host species are missing for a range of infectious diseases, although such hosts are potentially more affected than the normal vectors and reservoir species. If highly pathogenic avian influenza strikes rare birds of prey, this may have crucial impact on the predator species itself, but also on the food web in which it interacts. Here we present the first large-scale screening of raptors that regularly consume birds belonging to the natural reservoir of influenza A viruses. Influenza A virus prevalence was studied in two rare raptors, the white-tailed sea eagle (Haliaeetus albicilla) and the peregrine falcon (Falco peregrinus). Nestlings were screened for active (181 white-tailed sea eagles and 168 peregrine falcons) and past (123 white-tailed sea eagles and 6 peregrine falcons) infection in 2006-2007, and an additional 20 succumbed adult white-tailed sea eagles were sampled in 2003-2006. Neither high- nor low-pathogenic influenza infections were found in our sample, but this does not rule out that the former may have major impact on rare raptors and their food webs.

  • 178.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Latorre-Magalef, N.
    Hobson, K.A.
    van Wilgenburg, S.L.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Olsen, B.
    Fouchier, R.A.M.
    Waldenström, J.
    Within-season trends in natal orgin, body size, and influenza a virus subtypes in migrating mallards2012Conference paper (Other academic)
  • 179.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Latorre-Margalef, Neus
    Hobson, Keith A
    Van Wilgenburg, Steven L
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    Olsen, Björn
    Fouchier, R A M
    Waldenström, Jonas
    Within-season trends in natal origin, body size, and influenza A virus subtypes in migrating Mallards2012Conference paper (Refereed)
  • 180.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Latorre-Margalef, Neus
    Hobson, Keith H
    Van Wilgenburg, Steven L
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Olsen, Björn
    Fouchier, R A M
    Waldenström, Jonas
    Within-season trends in natal origin, body size, and influenza A virus subtypes in migrating Mallards2012Conference paper (Refereed)
  • 181.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment.
    Latorre-Margalef, Neus
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Hobson, Keith
    ldlife and Landscape Science, Environment Canada, Saskatoon.
    Steven, Van Wilgenburg
    ldlife and Landscape Science, Environment Canada, Saskatoon.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Olsen, Björn
    Section of Infectious Diseases, Department of Medical Sciences, Uppsala University Hospital, Uppsala.
    Fouchier, Ron
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, Kalmar.
    Disease dynamics and bird migration: linking mallards Anas platyrhynchos and subtype diversity of the influenza A virus in time and space2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 4, p. e35679-Article in journal (Refereed)
    Abstract [en]

    The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origin of staging ducks is vital to deciphering the dynamics of viral movement pathways. Ottenby is an important stopover site in southeast Sweden almost halfway downstream in the major Northwest European flyway, and is used by millions of waterfowl each year. Here, mallards were captured and sampled for influenza A virus infection, and positive samples were subtyped in order to study possible links to the natal area, which were determined by a novel approach combining banding recovery data and isotopic measurements (δ2H) of feathers grown on breeding grounds. Geographic assignments showed that the core natal areas of studied mallards were in Estonia, southern and central Finland, and northwestern Russia. This study demonstrates a clear temporal succession of latitudes of natal origin during the course of autumn migration. We also demonstrate a corresponding and concomitant shift in virus subtypes. Acknowledging that these two different patterns were based in part upon different data, a likely interpretation worth further testing is that the early arriving birds with more proximate origins have different influenza A subtypes than the more distantly originating late autumn birds. If true, this knowledge would allow novel insight into the origins and transmission of the influenza A virus among migratory hosts previously unavailable through conventional approaches.

  • 182.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Teacher Education.
    Latorre-Margalef, Neus
    Munster, Vincent
    Fouchier, Ron
    Osterhaus, Albert
    Elmberg, Johan
    Kristianstad University, School of Teacher Education.
    Olsen, Björn
    Wallensten, Anders
    Haemig, Paul D.
    Fransson, Thord
    Brudin, Lars
    Waldenström, Jonas
    Sub-lethal effects of low-pathogenic influenza A virus infection in mallards (Anas platyrhynchos) caught on autumn migration in Ottenby, Sweden2009In: Abstracts, 2nd Pan-European Duck Symposium, 2009, p. 27-Conference paper (Refereed)
  • 183.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Latorre-Margalef, Neus
    Munster, Vincent
    Wallensten, Anders
    Fouchier, Ron
    Osterhaus, Albert
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Olsen, Björn
    Waldenström, Jonas
    Are body mass and staging time in Mallards (Anas platyrhynchos) affected by infection of influenza A?2007Conference paper (Refereed)
  • 184.
    Gunnarsson, Gunnar
    et al.
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Sjöberg, Kjell
    SLU.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Pöysä, Hannu
    Finland.
    Nummi, Petri
    Finland.
    Does climate change affect the breeding success of Mallards Anas platyrynchos?2007Conference paper (Refereed)
  • 185. Hagman, M.
    et al.
    Kärvemo, S.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Löwenborg, K.
    Life at the edge: the nesting ecology of the world´s most northerly oviparous snake and its implications for conservation2013In: Reptiles in research: investigations of ecology, physiology, and behavior from desert to sea / [ed] Lutterschmidt, William I., Hauppauge, NY: Nova Science Publishers, Inc., 2013, p. 247-264Chapter in book (Refereed)
  • 186. Hagman, Mattias
    et al.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    "Museum mining": a method for investigating population trends2012In: 7th World Congressof Herpetology, Vancouver, Canda, August 2012: abstract book, 2012, p. 281-Conference paper (Refereed)
  • 187.
    Hagman, Mattias
    et al.
    Stockholm University.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Forskningsmiljön Man and Biosphere Health (MABH).
    Kärvemo, Simon
    Swedish University of Agricultural Sciences.
    Löwenborg, Kristin
    Stockholm University.
    Grass snakes (Natrix natrix) in Sweden decline together with their anthropogenic nesting-environments2012In: Herpetological Journal, ISSN 0268-0130, Vol. 22, no 3, p. 199-202Article in journal (Refereed)
    Abstract [en]

    In this paper we show that the number of grass snake (Natrix natrix L.) specimens deposited in Swedish museum collections has declined in the last eighty years, and that this is correlated with a dramatic national decrease in the number of livestock holdings. These results support the hypothesis that Swedish grass snakes are declining and that this may be linked to a loss of important nesting-environments provided by open manure heaps in small-scale farming. Our study suggests that information obtained from museum databases potentially may be used to explore population trends for snakes and other reptiles.

  • 188. Hessel, R.
    et al.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Nesting biology of the Hooded Crow Corvus corone cornix i a mixed residential-agricultural area in southern Sweden2010In: Ornis Svecica, ISSN 1102-6812, Vol. 20, p. 87-92Article in journal (Refereed)
  • 189.
    Holopainen, Sari
    et al.
    Finland.
    Arzel, Céline
    Finland.
    Dessborn, Lisa
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Gunnarsson, Gunnar
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Nummi, Petri
    Finland.
    Pöysä, Hannu
    Finland.
    Sjöberg, Kjell
    SLU.
    Habitat use in ducks breeding in boreal freshwater wetlands: a review2015In: European Journal of Wildlife Research, ISSN 1612-4642, E-ISSN 1439-0574, Vol. 61, no 3, p. 339-363Article in journal (Refereed)
    Abstract [en]

    Breeding habitats strongly influence duck reproduction and survival. The boreal biome harbours a large share of the worlds wetlands, which are important breeding sites for several duck species. Based on 98 studies in the peer-reviewed literature, we here synthesize and evaluate which habitat characteristics affect habitat use and reproduction of ducks breeding in boreal freshwater wetlands with respect to (1) species and guild (dabbling, diving and piscivorous ducks) and (2) breeding cycle stage (settling by pairs, nesting and brood rearing). We consider the following aspects related to habitat: wetland morphology and spatial aggregation, water characteristics, habitat structure and vegetation, and biotic interactions. Most of the peer-reviewed studies of duck habitat use in boreal wetlands are from North America and Fennoscandia, while nearly half of the boreal area lacks such studies. Few species dominate research thus far while several others have not been studied at all. Nest site use and success are mainly related to predator avoidance. Food resources and habitat structure are the key characteristics affecting habitat use by duck pairs and broods as well as breeding success, although there are differences between duck guilds. Among the commonly studied variables, there is little evidence that water characteristics affect duck habitat use or survival. The most notable knowledge gaps are found in the effects of anthropogenic activities on habitat use and breeding success of ducks. Because boreal breeding environments are increasingly affected by human activities, we underline the need for future studies combining climate variation with natural and anthropogenic disturbances.

  • 190.
    Kadin, Martina
    et al.
    Stockholm university.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Patterns and trade-offs among multiple ecosystem services from marine bird species2015In: 2nd World Seabird Conference: seabirds: Global ocean sentinels, 2015Conference paper (Refereed)
    Abstract [en]

    Ecosystem services (ES) are increasingly incorporated into management of marine and coastal resources. Local investigations of generation and utilization of ES are desirable but may be costly, highlighting a need to develop general tools helping to predict the ES associated with a particular resource or site. Functional guilds or trait-based approaches have been suggested as one way to predict the capacity to deliver desired ES. We assess the ES provided by six species, from pairs of two ecologically similar species in each of the families Anatidae, Alcidae and Phalacrocoracidae, and selected to show the applicability and limitations of such approaches applied to marine birds. The set of ES, interactions between them and differences between populations, are examined for each species. This helps to reveal when the characteristics of ES can be predicted based on knowledge from elsewhere or similar species, or when the local context needs to be analyzed. Our findings suggest that services more closely linked to ecological processes, which include many regulating and supporting services, are often similar within functional guilds. We also find that including breeding habits when defining guilds increases the general applicability of the concept. Cultural services, and services linked to local and scientific knowledge, depend to large extents on local context, on the other hand. This complicates the process of generalizing results regarding interactions and trade-offs between ES for species or populations that make significant contributions to substantially different kinds of services.

  • 191.
    Kaminski, Richard M.
    et al.
    Mississippi State University.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap. Kristianstad University, Research environment Man and Biosphere Health (MABH).
    An introduction to habitat use and selection by waterfowl in the northern hemisphere2014In: Wildfowl, ISSN 0954-6324, E-ISSN 2052-6458, no Special Issue 4, p. 9-16Article in journal (Refereed)
    Abstract [en]

    This introductory article aims to provide a theoretical framework to the topics of habitat use and selection by waterfowl (i.e. family Anatidae) in the northern hemisphere during the four stages of their annual cycle: autumn migration and winter, spring migration and pre-breeding, nesting and brood rearing, and postbreeding and moulting. Papers addressing each of these seasonal sectors of the annual cycle, which follow this introduction, were presented at the 6th North American Duck Symposium, “Ecology and Conservation of North American Waterfowl” in Memphis, Tennessee in January 2013. Here, we consider the theory and selected empirical evidence relevant to waterfowl habitat and resource use and selection that may affect individual survival and fitness of waterfowl in Nearctic and Palearctic ecozones. Additionally, where possible, a comparative taxonomic approach is attempted in the following papers to identify and generalise patterns in habitat and resource use and selection across waterfowl taxa that may influence biological outcomes for individuals, populations and species through space and time. Each of the subsequent papers use accumulated science-based information to recommend future opportunities and strategies for research and for habitat and population conservation. Collectively, our goals in synthesising information on waterfowl are to help sustain harvestable populations of waterfowl and to protect rare species amid worldwide changes in climate, landscape, economics, socio-politics and growth of human populations.

  • 192.
    Kraus, R. H. S.
    et al.
    Tyskland.
    Söderquist, Pär
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Gunnarsson, Gunnar
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Thulin, C.-G.
    Umeå University.
    Champagnon, Jocelyn
    Frankrike.
    Guillemain, Matthieu
    Frankrike.
    Kreisinger, Jakub
    Tjeckien.
    Prins, H. H. T.
    Nederländerna.
    Crooijmans, R. P. M. A.
    Nederländerna.
    Elmberg, Johan
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Freigelassenes Federwild führt zu kontinent-weiter genetischer Introgression: die sich ändernde genetische Landschaft der Stockente (Anas platyrhynchos) in Europa2015Conference paper (Refereed)
  • 193.
    Kraus, R.H.S.
    et al.
    Tyskland.
    Söderquist, Pär
    Kristianstad University, Research environment Man & Biosphere Health (MABH). Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Gunnarsson, Gunnar
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Thulin, Carl-Gustaf
    Umeå university.
    Champagnon, Jocelyn
    Frankrike.
    Guillemain, Matthieu
    Frankrike.
    Kreisinger, Jakub
    Tjeckien.
    Prins, H.H.T.
    Nederländerna.
    Crooijmans, R.P.M.A.
    Nederländerna.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment, Avdelningen för Naturvetenskap.
    Freigelassenes Federwild führt zu kontinent-weiter genetischer Introgression: die sich ändernde genetische Landschaft der Stockente Anas platyrhynchos in Europa2015Conference paper (Refereed)
    Abstract [de]

    Es ist eine seit langem übliche Praxis in Forstwirtschaft, Fischerei und allgemeinem Wildtiermanagement, Wildtierbestände gezielt aufzustocken. In den letzten ca. zehn Jahren haben aber solche Programme Aufmerksamkeit erregt, in denen lokale Bestände von Tierarten mit Individuen der gleichen Art, aber aus anderen Regionen und damit potentiell nicht-nativen Genomen aufgestockt wurden. Die Stockente Anas platyrhynchos ist ein geeignetes Modell um die genetischen Effekte solcher großskaligen Freisetzungen auf den einheimischen Genpool zu untersuchen, weil sie die am weitesten verbreitete und zahlreichste Entenart der Welt ist, über weite Strecken migrieren kann und gleichzeitig global das wichtigste Federwild darstellt. In vielen europäischen Ländern wird die Stockente seit etwa den frühen 1970er Jahren auch auf speziellen Farmen gezüchtet und zu Jagdzwecken ausgesetzt. So gehen aktuelle Schätzungen davon aus, dass jährlich etwa drei Millionen junge Enten nur zum Zweck der Aufstockung zur Jagd an europäischen Gewässern ausgesetzt werden. Die Ziele unserer Studie waren herauszufinden, ob sich Enten von Farmpopulationen genetisch von wilden Enten unterscheiden lassen, ob es Anzeichen früherer oder anhaltender genetischer Introgression zwischen diesen beiden Gruppen gibt und ob sich die genetische Struktur der wilden Entenpopulationen seit der großskaligen Entenaufstockung verändert hat. Dazu verwendeten wir 360 SNP Marker (Single Nucleotide Polymorhpism) um die genetische Struktur von historischen wilden Stockenten (Museumsproben), zeitgenössischen wilden Stockenten und Farm-Enten zu vergleichen (N = 591). Wir fanden klare genetische Unterschiede zwischen wilden Stockenten und Farm-Enten in mehreren Ländern Europas. Ebenfalls konnten wir genetische Introgression von Genen der Farm-Enten in die wilde Stockentenpopulation zeigen. Die Vermischung scheint bisher zwar messbar aber noch gering zu sein, da auf Farmen gezüchtete Stockenten in der Wildnis geringe Überlebensraten aufweisen. Dennoch sollte die weitere Einkreuzung von Farm-Enten in die wilden Stockentenpopulationen so gering wie möglich gehalten werden, da durch anhaltende genetische Introgression möglicherweise in Zukunft lokale Anpassungen der wilden Stockenten geschwächt werden, was eine Bedrohung dieser Bestände darstellen könnte.

  • 194.
    Kraus, Robert H. S.
    et al.
    Resource Ecology Group, Wageningen University.
    Kerstens, Hindrik H. D.
    Animal Breeding and Genomics Centre, Wageningen University.
    van Hooft, Pim
    Resource Ecology Group, Wageningen University.
    Crooijmans, Richard P. M. A.
    Animal Breeding and Genomics Centre, Wageningen University.
    van der Poel, Jan J.
    Animal Breeding and Genomics Centre, Wageningen University.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Vignal, Alain
    UMR Génétique Cellulaire, Centre INRA de Toulouse, Castanet-Tolosan.
    Huang, Yinhua
    State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing.
    Li, Ning
    State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing.
    Prins, Herbert H. T.
    Resource Ecology Group, Wageningen University.
    Groenen, Martien A. M.
    Animal Breeding and Genomics Centre, Wageningen University.
    Genome wide SNP discovery, analysis and evaluation in mallard (Anas platyrhynchos)2011In: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 12, p. 150-Article in journal (Refereed)
    Abstract [en]

    Background: Next generation sequencing technologies allow to obtain at low cost the genomic sequence information that currently lacks for most economically and ecologically important organisms. For the mallard duck genomic data is limited. The mallard is, besides a species of large agricultural and societal importance, also the focal species when it comes to long distance dispersal of Avian Influenza. For large scale identification of SNPs we performed Illumina sequencing of wild mallard DNA and compared our data with ongoing genome and EST sequencing of domesticated conspecifics. This is the first study of its kind for waterfowl. Results: More than one billion base pairs of sequence information were generated resulting in a 16x coverage of a reduced representation library of the mallard genome. Sequence reads were aligned to a draft domesticated duck reference genome and allowed for the detection of over 122,000 SNPs within our mallard sequence dataset. In addition, almost 62,000 nucleotide positions on the domesticated duck reference showed a different nucleotide compared to wild mallard. Approximately 20,000 SNPs identified within our data were shared with SNPs identified in the sequenced domestic duck or in EST sequencing projects. The shared SNPs were considered to be highly reliable and were used to benchmark non-shared SNPs for quality. Genotyping of a representative sample of 364 SNPs resulted in a SNP conversion rate of 99.7%. The correlation of the minor allele count and observed minor allele frequency in the SNP discovery pool was 0.72. Conclusion: We identified almost 150,000 SNPs in wild mallards that will likely yield good results in genotyping. Of these, similar to 101,000 SNPs were detected within our wild mallard sequences and similar to 49,000 were detected between wild and domesticated duck data. In the similar to 101,000 SNPs we found a subset of similar to 20,000 SNPs shared between wild mallards and the sequenced domesticated duck suggesting a low genetic divergence. Comparison of quality metrics between the total SNP set (122,000 + 62,000 = 184,000 SNPs) and the validated subset shows similar characteristics for both sets. This indicates that we have detected a large amount (similar to 150,000) of accurately inferred mallard SNPs, which will benefit bird evolutionary studies, ecological studies (e. g. disentangling migratory connectivity) and industrial breeding programs.

  • 195.
    Kraus, Robert
    et al.
    Resource Ecology Group, Wageningen University.
    Kerstens, Hindrik
    Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen.
    van Hooft, Pim
    Resource Ecology Group, Wageningen University.
    Megens, Hendrik-Jan
    Animal Breeding and Genomics Centre, Wageningen University.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Tsvey, Arseny
    Biological Station Rybachy of the Zoological institute, Kaliningrad.
    Sartakov, Dmitry
    Ecological Watch of Siberia, Omsk.
    Soloviev, Sergej
    Department of Chemistry, Omsk State University.
    Crooijmans, Richard
    Animal Breeding and Genomics Centre, Wageningen University.
    Groenen, Martien
    Animal Breeding and Genomics Centre, Wageningen University.
    Ydenberg, Ronald
    Resource Ecology Group, Wageningen University.
    Prins, Herbert
    Resource Ecology Group, Wageningen University.
    Widespread horizontal genomic exchange does not erode species barriers among sympatric ducks2012In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 12, p. 45-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:The study of speciation and maintenance of species barriers is at the core of evolutionary biology. During speciation the genome of one population becomes separated from other populations of the same species, which may lead to genomic incompatibility with time. This separation is complete when no fertile offspring is produced from inter-population matings, which is the basis of the biological species concept. Birds, in particular ducks, are recognised as a challenging and illustrative group of higher vertebrates for speciation studies. There are many sympatric and ecologically similar duck species, among which fertile hybrids occur relatively frequently in nature, yet these species remain distinct.RESULTS:We show that the degree of shared single nucleotide polymorphisms (SNPs) between five species of dabbling ducks (genus Anas) is an order of magnitude higher than that previously reported between any pair of eukaryotic species with comparable evolutionary distances. We demonstrate that hybridisation has led to sustained exchange of genetic material between duck species on an evolutionary time scale without disintegrating species boundaries. Even though behavioural, genetic and ecological factors uphold species boundaries in ducks, we detect opposing forces allowing for viable interspecific hybrids, with long-term evolutionary implications. Based on the superspecies concept we here introduce the novel term "supra-population" to explain the persistence of SNPs identical by descent within the studied ducks despite their history as distinct species dating back millions of years.CONCLUSIONS:By reviewing evidence from speciation theory, palaeogeography and palaeontology we propose a fundamentally new model of speciation to accommodate our genetic findings in dabbling ducks. This model, we argue, may also shed light on longstanding unresolved general speciation and hybridisation patterns in higher organisms, e.g. in other bird groups with unusually high hybridisation rates. Observed parallels to horizontal gene transfer in bacteria facilitate the understanding of why ducks have been such an evolutionarily successful group of animals. There is large evolutionary potential in the ability to exchange genes among species and the resulting dramatic increase of effective population size to counter selective constraints.

  • 196.
    Latorre-Margalef, Neus
    et al.
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Gunnarsson, Gunnar
    Kristianstad University, School of Education and Environment.
    Munster, Vincent J.
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Fouchier, Ron A. M.
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Osterhaus, Albert D. M. E.
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Olsen, Björn
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Wallensten, Anders
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Fransson, Thord
    Bird Ringing Centre, Swedish Museum of Natural History, Stockholm.
    Brudin, Lars
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Waldenstrom, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Does influenza A affect body condition of wild mallard ducks, or vice versa?: a reply to Flint and Franson2009In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 276, no 1666, p. 2347-2349Article in journal (Refereed)
  • 197.
    Latorre-Margalef, Neus
    et al.
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Gunnarsson, Gunnar
    Kristianstad University, School of Education and Environment.
    Munster, Vincent J.
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Fouchier, Ron A. M.
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Osterhaus, Albert D. M. E.
    Department of Virology, Erasmus Medical Center, Rotterdam.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Olsen, Björn
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Wallensten, Anders
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Haemig, Paul D.
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Fransson, Thord
    Bird Ringing Centre, Swedish Museum of Natural History, Stockholm.
    Brudin, Lars
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Waldenström, Jonas
    Section for Zoonotic Ecology and Epidemiology, School of Pure and Applied Natural Sciences, University of Kalmar.
    Effects of influenza A virus infection on migrating mallard ducks2009In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 276, no 1659, p. 1029-1036Article in journal (Refereed)
    Abstract [en]

    The natural reservoir of influenza A virus is waterfowl, particularly dabbling ducks (genus Anas). Although it has long been assumed that waterfowl are asymptomatic carriers of the virus, a recent study found that low-pathogenic avian influenza (LPAI) infection in Bewick's swans (Cygnus columbianus bewickii) negatively affected stopover time, body mass and feeding behaviour. In the present study, we investigated whether LPAI infection incurred ecological or physiological costs to migratory mallards (Anas platyrhynchos) in terms of body mass loss and staging time, and whether such costs could influence the likelihood for long-distance dispersal of the avian influenza virus by individual ducks. During the autumn migrations of 2002-2007, we collected faecal samples (n=10918) and biometric data from mallards captured and banded at Ottenby, a major staging site in a flyway connecting breeding and wintering areas of European waterfowl. Body mass was significantly lower in infected ducks than in uninfected ducks (mean difference almost 20 g over all groups), and the amount of virus shed by infected juveniles was negatively correlated with body mass. There was no general effect of infection on staging time, except for juveniles in September, in which birds that shed fewer viruses stayed shorter than birds that shed more viruses. LPAI infection did not affect speed or distance of subsequent migration. The data from recaptured individuals showed that the maximum duration of infection was on average 8.3 days (s.e. 0.5), with a mean minimum duration of virus shedding of only 3.1 days (s.e. 0.1). Shedding time decreased during the season, suggesting that mallards acquire transient immunity for LPAI infection. In conclusion, deteriorated body mass following infection was detected, but it remains to be seen whether this has more long-term fitness effects. The short virus shedding time suggests that individual mallards are less likely to spread the virus at continental or intercontinental scales.

  • 198.
    Lundberg, Per
    et al.
    Lunds universitet.
    Kjellander, Petter
    Sveriges lantbruksuniversitet, Uppsala.
    Hörnell-Willebrand, Maria
    Sveriges lantbruksuniversitet, Uppsala.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Liberg, Olof
    Sveriges lantbruksuniversitet, Uppsala.
    Ericsson, Göran
    Sveriges lantbruksuniversitet, Umeå.
    Andrén, Henrik
    Sveriges lantbruksuniversitet, Uppsala.
    Spong, Göran
    Sveriges lantbruksuniversitet, Umeå.
    Thulin, Carl-Gustaf
    Sveriges lantbruksuniversitet, Umeå.
    Åtgärder — beskattning2010In: Vilt, människa, samhälle / [ed] Danell, Kjell, Bergström, Roger, Stockholm: Liber , 2010, p. 249-269Chapter in book (Other (popular science, discussion, etc.))
  • 199.
    Lundberg, Per
    et al.
    Lunds universitet.
    Mörner, Torsten
    Statens veterinärmedicinska anstalt, Uppsala.
    Bergström, Roger
    Skogforsk, Uppsala.
    Danell, Kjell
    Sveriges lantbruksuniversitet, Umeå.
    Elmberg, Johan
    Kristianstad University, School of Education and Environment.
    Ericsson, Göran
    Sveriges lantbruksuniversitet, Umeå.
    Viltpopulationer och deras dynamik2010In: Vilt, människa, samhälle / [ed] Danell, Kjell, Bergström, Roger, Stockholm: Liber , 2010, p. 53-79Chapter in book (Other (popular science, discussion, etc.))
  • 200.
    Miaud, Claude
    et al.
    University of Savoie, Mountain Interdisciplinary Scientific Center, Laboratory Aquatic Ecosystems and Interfaces, Le Bourget du Lac.
    Guyétant, Robert
    University of Savoie, Mountain Interdisciplinary Scientific Center, Laboratory Aquatic Ecosystems and Interfaces, Le Bourget du Lac.
    Elmberg, Johan
    Department of Animal Ecology, Swedish University of Agricultural Sciences, Umeå.
    Variations in life-history traits in the common frog Rana temporaria (Amphibia: Anura): a literature review and new data from the French Alps1999In: Journal of Zoology, ISSN 0952-8369, E-ISSN 1469-7998, Vol. 249, no 1, p. 61-73Article in journal (Refereed)
    Abstract [en]

    Life-history traits of Rana temporaria were studied in an alpine French population and in the literature. In the living frogs, mean adult body length was greater in females than in males. Sexual dimorphism in body length was 0.109 using Lovich & Gibbons (1992) formula, but tended to decrease with age. Age of adult frogs was assessed by skeletochronology, and age distribution was not significantly different between the sexes (range 4-15 years in males, 5-12 in females). Adult survival rate was about 0.80 in both sexes. Once maturity was reached, the total expected longevity was 6.1 years in males and 5.5 years in females. Age and body length were positively correlated in both sexes. The growth coefficient (K) was 0.47 in males, and 0.55 in females, mainly reflected as faster female growth between metamorphosis and maturation. Growth rate generally decreased before sexual maturity was reached. On average, females matured 1 year later than males. Newly metamorphosed froglets averaged 16.1 mm. When combined with published data from 12 European populations of R. temporaria, the following general patterns emerge. Mean adult body length is significantly greater in females than in males, and mean body length at maturity shows the same trend. Variation in mean age at maturity and in longevity are considerable among populations, but there is no consistent trend of difference between the sexes. Body length and age are correlated between males and females, i.e. populations with long and old males also have long and old females. Mean adult body length, mean body length at maturity, age at maturity, and longevity all increase with decreasing activity period. Adults exposed to a short activity period grow slower but attain a greater final length. Sexual dimorphism in body length generally increases as activity period gets shorter. Polygons describing norms of reaction for maturation in an age-body length space are similarly oriented in both sexes, but with a wider range in age for females. This is due to an older age at maturity for females in populations with a short activity season. Mean age and length at maturity are significantly correlated in females, but not in males, partly supporting the hypothesis that this species has a flexible pattern of development. Observed patterns are compared with predictions from life-history theory, paying attention to all life stages and environmental variation.

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