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  • 1.
    Ahlén, Ingemar
    et al.
    SLU.
    Angelstam, Per
    SLU.
    Bensch, Staffan
    Lunds universitet.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Enemar, Anders
    Göteborgs universitet.
    Fagerström,, Torbjörn
    SLU.
    Green, Martin
    Lunds universitet.
    Gustafsson, Lars
    Uppsala universitet.
    Gustafsson, Lena
    SLU.
    Mikael, Hake
    SLU.
    Dennis, Hasselquist,
    Lunds universitet.
    Hedenström, Anders
    Lunds universitet.
    H-Lindgren, Christina
    Umeå universitet.
    Lindberg, Peter
    Göteborgs universitet.
    Lindström, Åke
    Lunds universitet.
    Michanek, Gabriel
    Luleå tekniska universitet.
    Nilsson, Leif
    Lunds universitet.
    Nilsson, Sven G
    Lunds universitet.
    Pärt, Tomas
    SLU.
    Sundberg, Jan
    Uppsala universitet.
    Svensson, Sören
    Lunds universitet.
    Tjernberg, Martin
    SLU.
    Ulfstrand, Staffan
    Uppsala universitet.
    Brusewitz, Gunnar
    Stockholms universitet.
    Edman, Stefan
    Chalmers tekniska högskola.
    Jonsson, Lars
    Uppsala universitet.
    Landell, Nils-Erik
    Wahlstedt, Jens
    Emanuelsson, Urban
    Centrum för biologisk mångfald.
    Ingelög, Torleif
    Artdatabanken.
    Karlsson, Mikael
    Svenska naturskyddsföreningen.
    Kristoferson, Lars
    WWF.
    Lindell, Lars
    Sveriges Ornitologiska Förening.
    Nya järnvägen hotar unikt naturområde2002Ingår i: Aftonbladet, ISSN 1103-9000Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 2.
    Arzel, C.
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, M.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    A flyway perspective of foraging activity in Eurasian Green-winged Teal, Anas crecca crecca2007Ingår i: Canadian Journal of Zoology, ISSN 0008-4301, E-ISSN 1480-3283, Vol. 85, nr 1, s. 81-91Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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  • 3.
    Arzel, Celiné
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, M.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Gurd, D.B.
    Centre for Wildlife Ecology, Department of Biological Sciences, Simon Fraser University, Burnaby, BC.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Fritz, H.
    Centre d’Etudes Biologiques de Chizé, CNRS UPR 1934, Beauvoir-sur-Niort.
    Arnaud, A.
    Station Biologique La Tour du Valat, Le Sambuc, Arles.
    Pin, C.
    Station Biologique La Tour du Valat, Le Sambuc, Arles.
    Bosca, F.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Experimental functional response and inter-individual variation in foraging rate of teal (Anas crecca)2007Ingår i: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 75, nr 1, s. 66-71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 4.
    Arzel, Céline
    et al.
    Department of Biology, University of Turku.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Nummi, Petri
    Pöysä, Hannu
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Sjöberg, Kjell
    Does changing spring phenology affect short and long distance migratory waterfowl similarly?2010Ingår i: The abstract book: Symposium : The global environmental change: messages from birds. Espoo, 17-19 November, 2010, s. 43-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

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

  • 5.
    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)
  • 6.
    Arzel, Céline
    et al.
    University of Turku.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Pöysä, Hannu
    Joensuu Game and Fisheries Research.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man and Biosphere Health (MABH).
    Nummi, Petri
    University of Helsinki.
    Sjöberg, Kjell
    Swedish University of Agricultural Sciences, Umeå.
    Early springs and breeding performance in two sympatric duck species with different migration strategies2014Ingår i: Ibis, ISSN 0019-1019, E-ISSN 1474-919X, Vol. 156, nr 2, s. 288-298Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 7.
    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)
  • 8.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Time and microhabitat use in pre-breeding dabbling ducks Anas spp. in sub-arctic Norway: does the long trip make a difference?2009Ingår i: Abstracts, 2nd Pan-European Duck Symposium, 2009, s. 44-Konferensbidrag (Refereegranskat)
  • 9.
    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.

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

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

  • 11.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, M.
    CNERA Avifaune Migratrice.
    Ecology of spring-migrating Anatidae: a review2006Ingår i: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 147, nr 2, s. 167-184Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

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

  • 12.
    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)
  • 13.
    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.

  • 14.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Waterfowl migration and wetland management at the European scale2009Ingår i: Abstracts, 2nd Pan-European Duck Symposium, 2009, s. 33-Konferensbidrag (Refereegranskat)
  • 15.
    Arzel, Céline
    et al.
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Institutionen för matematik och naturvetenskap.
    Guillemain, Matthieu
    Legagneux, Pierre
    Bosca, Fabrice
    Chambouleyron, Mathieu
    Lepley, Michel
    Pin, Christophe
    Arnaud, Antoine
    Schricke, Vincent
    Average mass of seeds encountered by foraging dabbling ducks in western Europe2007Ingår i: Wildlife Biology, ISSN 0909-6396, E-ISSN 1903-220X, Vol. 13, nr 3, s. 328-336Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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  • 16.
    Arzel, Céline
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Lepley, Michel
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Bosca, Fabrice
    Legagneux, Pierre
    CEBC, CNRS UPR 1934 Villiers-en-Bois, Beauvoir sur Niort.
    Nogues, Jean-Baptiste
    Les Amis des Marais du Vigueirat, Mas Thibert, Arles.
    A flyway perspective on food resource abundance in a long-distance migrant, the Eurasian teal (Anas crecca)2009Ingår i: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 150, nr 1, s. 61-73Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 17.
    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.

  • 18.
    Arzel, Céline
    et al.
    Department of Biology, University of Turku.
    Rönkä, Mia
    Davranche, Aurélie
    Erlangen-Nürnberg University Institute of Geography.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Saari, Lennart
    Rainio, Kalle
    Lehikionen, Esa
    Are ducks able to adapt their migratory habits to environmental change?2010Ingår i: The abstract book: Symposium : The global environmental change: messages from birds. Espoo, 17-19 November, 2010, s. 25-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

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

  • 19. Arzél, Céline
    et al.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Comportement et alimentation de la Sarcelle d'hiver Anas crecca lors de la migration prénuptial2010Ingår i: Ornithos: revue d'ornithologie de terrain, ISSN 1254-2962, Vol. 17, nr 5, s. 307-315Artikel i tidskrift (Övrigt vetenskapligt)
  • 20.
    Beery, Thomas
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    From environmental connectedness to sustainable futures: topophilia and human affiliation with nature2015Ingår i: European Human Behaviour and Evolution Association Annual Conference, University of Helsinki, March 29-April 1, 2015, 2015, s. 57-58Konferensbidrag (Refereegranskat)
    Abstract [en]

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

  • 21.
    Beery, Thomas
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Jönsson, K. Ingemar
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    From environmental connectedness to sustainable futures: topophilia and human affiliation with nature2015Ingår i: Sustainability, E-ISSN 2071-1050, Vol. 7, nr 7, s. 8837-8854Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

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  • 22.
    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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  • 23.
    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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  • 24. 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))
  • 25.
    Brochet, Anne-Laure
    et al.
    CNERA Avifaune migratrice, Office National de la Chasse et de la Faune Sauvage, Arles.
    Dessborn, Lisa
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Legagneux, P.
    Département de Biologie, Université Laval, Pavillon Vachon.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Gauthier-Clerc, M.
    Centre de Recherche de la Tour du Valat, Arles.
    Fritz, H.
    Université Claude Bernard Lyon 1, CNRS UMR 5558 Biométrie et Biologie Evolutive, Université de Lyon, Villeurbanne.
    Guillemain, M.
    CNERA Avifaune migratrice, Office National de la Chasse et de la Faune Sauvage, Arles.
    Is diet segregation between dabbling ducks due to food partitioning?: a review of seasonal patterns in the Western Palearctic2012Ingår i: Journal of Zoology, ISSN 0952-8369, E-ISSN 1469-7998, Vol. 286, nr 3, s. 171-178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 26.
    Champagnon, Jocelyn
    et al.
    Office National de la Chasse et de la Faune Sauvage – CNERA Avifaune Migratrice, Le Sambuc, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Guillemain, Matthieu
    Office National de la Chasse et de la Faune Sauvage – CNERA Avifaune Migratrice, Le Sambuc, Arles.
    Gauthier-Clerc, Michel
    Centre de Recherche de la Tour du Valat, Le Sambuc, Arles.
    Lebreton, Jean-Dominique
    Centre d’Ecologie Fonctionnelle et Evolutive UMR 5175 - CNRS, Montpellier.
    Conspecifics can be aliens too: a review of effects of restocking practices in vertebrates2012Ingår i: Journal for Nature Conservation, ISSN 1617-1381, E-ISSN 1618-1093, Vol. 20, nr 4, s. 231-241Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 27.
    Champagnon, Jocelyn
    et al.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, Arles.
    Guillemain, Matthieu
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Folkesson, Karin
    Gauthier-Clerc, Michel
    Centre de Recherche de la Tour du Valat, Le Sambuc, Arles.
    Changes in Mallard Anas platyrhynchos bill morphology after 30 years of supplemental stocking2010Ingår i: Bird Study, ISSN 0006-3657, E-ISSN 1944-6705, Vol. 57, nr 3, s. 344-351Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Capsule Massive releases of captive-reared Mallard for hunting purposes have been practiced for 30 years. During this period the number of lamellae per centimetre of bill length in wild Mallard populations has decreased. Aims Every year since the 1970s, several million captive Mallard have been released in Europe. This may lead to a spread of unnatural phenotypes into the wild. Nevertheless, the consequences of such introductions have not been examined. Methods Two widespread and common migratory ducks were studied: Mallard Anas platyrhynchos and Teal A. crecca. Mallard is the only duck species for which stocking programmes occur, and Teal served as a control. In a 'before-after' design, we compared duck bill lamellar density over the last 30 years. Results Lamellar density in Mallard, but not Teal, decreased. The observed 10% decrease occurred in the first (proximate) centimetre of the bill, the most crucial in terms of food filtration. Conclusions We hypothesize that the change in bill morphology was because of the propagation of captive Mallard into the wild: captive Mallard eat mainly large items, relaxing the natural selection pressure maintaining high lamellar density for sieving small prey in wild ducks.

  • 28.
    Champagnon, Jocelyn
    et al.
    French Hunting and Wildlife Agency, Arles, France.
    Guillemain, Matthieu
    French Hunting and Wildlife Agency, Arles, France.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Folkesson, Karin
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Gauthier-Clerc, Michel
    Tour du Valat Research Center, Arles.
    Do stocking programs result in maladapted populations?: mallard bill morphology after 30 years of massive releases2011Ingår i: Abstracts: Joint meeting of the 11th North American Crane Workshop and the 34th Annual Meeting of The Waterbird Society, Grand Island, Nebraska, USA, March 13-16, 2011, 2011, s. 31-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Every year since the 1970s, several million captive Mallard have been released in Europe for hunting purposes. This may lead to a spread of unnatural phenotypes into the wild. Two widespread and common migratory ducks were studied: Mallard    Anas platyrhynchos and Teal A. crecca. Mallard is the only duck species for which large-scale stocking programs occur in the region, and Teal hence serves as a control. In a « before-after » design, we compared duck bill lamellar density over the last thirty years. Lamellar density in Mallard, but not Teal, decreased. The observed 10 % decrease occurred in the first (proximate) centimetre of the bill, the most crucial in terms of food filtration. We hypothesize the observed change in bill morphology was due to the propagation of captive Mallard into the wild: captive Mallard mainly eat large items, relaxing the natural selection pressure maintaining high lamellar density for sieving small preys in wild ducks.

  • 29.
    Champagnon, Jocelyn
    et al.
    French Hunting and Wildlife Agency, Le Sambuc, Arles.
    Guillemain, Matthieu
    French Hunting and Wildlife Agency, Le Sambuc, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Massec, Grégoire
    Marais du Vigueirat, Mas Thibert, Arles.
    Gauthier-Clerc, Michel
    Tour du Valat Research Center, Le Sambuc, Arles.
    Survival probability and morphological adaptation of captive-reared Mallard Anasplatyrhynchos after release into the wild2011Ingår i: Abstracts: Joint meeting of the Association of Field Ornithologists, the Cooper Ornithological Society, and the Wilson Ornithological Society, Kearny, Nebraska, USA, March 9-12, 2011, 2011, s. 16-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Captive-reared animals released as part of reinforcement programmes are considered less likely to survive than their wild conspecifics. One of the possible causes for this is reduced digestion efficiency. We studied adaptation of the digestive system in Mallard, a species with high adaptability to its environment. Body condition and digestive organs were compared between three groups: captive-reared Mallards remaining in a game farm, captive-reared Mallards released into the wild as juveniles and wild Mallards. We also assessed difference in diet between released birds and wild birds, and conducted a one-year survival analysis of captive-reared birds released in a hunting-free area. Released Mallards had a smaller gizzard than wild birds, but there was no difference between captive-reared and wild Mallards in the size of others organs in the gastro-intestinal tract. Body condition of captive-reared Mallards was poorer than wild ones, and this was only partially improved after release. Survival probability of captive-reared Mallards was low, compared to documented survival of wild Mallards. In particular, high mortality occurred when additional food provisioning was stopped and during harsh winter periods. We argue that in spite of a viable digestive system, pre-release conditions experienced by captivereared ducks impeded restocking success. In the context of massive releases of this species for hunting purposes (several million birds per year in Europe), low survival due to a combination of high hunting pressure and poor condition could limit the number of farmed birds surviving to breed and thus limit introgression of "captive genes" into the wild population.

  • 30.
    Champagnon, Jocelyn
    et al.
    Frankrike.
    Guillemain, Matthieu
    Frankrike.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Massez, Grégoire
    Frankrike.
    Cavallo, Francois
    Frankrike.
    Gauthier-Clerc, Michel
    Frankrike.
    Low survival after release into the wild: assessing “the burden of captivity” on Mallard physiology and behaviour2012Ingår i: European Journal of Wildlife Research, ISSN 1612-4642, E-ISSN 1439-0574, Vol. 58, nr 1, s. 255-267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Captive-reared animals used in reinforcement programs are generally less likely to survive than wild conspecifics. Digestion efficiency and naive behaviour are two likely reasons for this pattern. The Mallard is a species with high adaptability to its environment and in which massive reinforcement programs are carried out. We studied physiological and behavioural factors potentially affecting body condition and survival of captive-reared Mallards after being released. Digestive system morphology and an index of body condition were compared among three groups: captive-reared birds remaining in a farm (control), captive-reared birds released into the wild as juveniles (released) and wild-born birds (wild). We also compared behaviour and diet of released vs. wild Mallards. Finally, we conducted a 1-year survival analysis of captive-reared birds after release in a hunting-free area. Gizzard weight was lower in control Mallards, but the size of other organs did not differ between controls and wild birds. The difference in gizzard weight between released and wild birds disappeared after some time in the wild. Diet analyses suggest that released Mallards show a greater preference than wild for anthropogenic food (waste grain, bait). Despite similar time-budgets, released Mallards never attained the body condition of wild birds. As a consequence, survival probability in released Mallards was low, especially when food provisioning was stopped and during harsh winter periods. We argue that the low survival of released Mallards likely has a physiological rather than a behavioural (foraging) origin. In any case, extremely few released birds live long enough to potentially enter the breeding population, even without hunting. In the context of massive releases presently carried out for hunting purposes, our study indicates a low likelihood for genetic introgression by captive-reared birds into the wild population.

  • 31.
    Champagnon, Jocelyn
    et al.
    Frankrike.
    Guillemain, Matthieu
    Frankrike.
    Gauthier-Clerc, Michel
    Frankrike.
    Lebreton, Jean-Dominique
    Frankrike.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap.
    Consequences of massive bird releases for hunting purposes: mallard Anas platyrhynchos in the Camargue, Southern France2009Ingår i: Wildfowl, ISSN 0954-6324, E-ISSN 2052-6458, nr Special issue 2, s. 184-191Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The release of captive-reared fish and game animals into the wild is a common management practice in Europe and North America. In Europe, millions of reared birds are released each year yet the consequences of these release programmes have received little attention. This paper describes the massive introduction of Mallard Anas platyrhynchos, a native migrant species released into the wild to increase the size of hunted populations. It provides the rationale for current and forthcoming experiments aimed at determining the effects of the augmentation of Mallard stocks on wild population genotype and survival rates.

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  • 32. Clausen, P.
    et al.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Fox, A.
    Heldbjerg, H.
    Lindström, Å.
    Pöysä, Hannu
    Mallard declines in Western Europe: evidence of true population declines or just short-stopping in milder winters?2009Ingår i: Abstracts, 2nd Pan-European Duck Symposium, 2009, s. 49-Konferensbidrag (Refereegranskat)
  • 33. Czarnezki, Jason J
    et al.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Tuvendal, Magnus
    Benefits from nature are not a private thing2016Ingår i: EarthDesk, Vol. Oct 19Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 34.
    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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  • 35.
    Danell, Kjell
    et al.
    Sveriges lantbruksuniversitet, Umeå.
    Bergström, Roger
    Skogforsk, Uppsala.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Emanuelsson, Urban
    Sveriges lantbruksuniversitet, Alnarp.
    Christiernsson, Anna
    Luleå tekniska universitet.
    Viltet2010Ingår i: Vilt, människa, samhälle / [ed] Danell, Kjell, Bergström, Roger, Stockholm: Liber , 2010, s. 17-31Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 36.
    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)
  • 37.
    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)
  • 38.
    Davranche, Aurélie
    et al.
    Erlangen-Nürnberg University Institute of Geography.
    Arzel, Céline
    Department of Biology, University of Turku.
    Pöysä, Hannu
    Nummi, Petri
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Clausen, Preben
    Pellikka, Petri
    Lefebvre, Gaëtan
    Poulin, Brigitte
    Space based tools to monitor the habitats of migratory waterbirds2010Ingår i: The abstract book: Symposium : The global environmental change: messages from birds. Espoo, 17-19 November, 2010, s. 44-Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Natural fluctuations in the availability of suitable habitat coupled with anthropogenic activities (hunting, agriculture, tourism, urbanism) and anticipated modifications due to climate change confront migratory waterbirds with a formidable challenge. Among them, dabbling ducks, greatly rely on local exogenous resources to fulfil their energy requirements. Habitat suitability along their flyway is of primary importance as any change might induce dramatic effects on individual survival and breeding success. Although, the monitoring of such sensitive flooded areas that are wetlands stopover sites is usually complex, space based techniques, with an exhaustive and systematic covering of the territory and a periodical data acquisition, can explore cost-efficiently the ecological conditions for migratory species in these environments. Hence, multiseason reflectance data from radiometrically and geometrically corrected multispectral SPOT-5 scenes, combined with thorough field campaigns and land cover digitizing using data mining, can provide robust tools for habitat monitoring and help the conservation of wetlands for migrants.

  • 39.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Brochet, A. L.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Legagneux, P.
    Département de Biologie and Centre d’Études Nordiques, Pavillon Vachon Université Laval, Québec.
    Gauthier-Clerc, M.
    Centre de Recherche de la Tour du Valat, Le Sambuc, Arles,.
    Guillemain, M.
    Office National de la Chasse et de la Faune Sauvage, CNERA Avifaune Migratrice, La Tour du Valat, Le Sambuc, Arles.
    Geographical and temporal patterns in the diet of pintail Anas acuta, wigeon Anas penelope, mallard Anas platyrhynchos and teal Anas crecca in the Western Palearctic2011Ingår i: European Journal of Wildlife Research, ISSN 1612-4642, E-ISSN 1439-0574, Vol. 57, nr 6, s. 1119-1129Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dabbling ducks are important quarry species, and as a result, they are relatively well studied. Over the last century, considerable effort has been made to describe their diet and food requirements. In this review, we compile present knowledge about the diet of four widespread dabbling ducks (wigeon, pintail, mallard and teal) in the Western Palearctic. Previous diet research has a spatio-temporal bias towards autumn/winter and the western parts of Europe. The limited number of studies from the breeding season reveals an increase in invertebrates in the diet compared to other seasons, but with some differences between adults and ducklings. Adult ducks eat a larger proportion of benthic invertebrates, whereas ducklings feed relatively more on emerging invertebrates. The most important plant species (seeds) based on frequency occurrence was found to vary with a geographic gradient. Carex spp., Hordeum vulgare and Hippuris vulgaris are common in the diet of birds at northern latitudes, whereas taxa such as Oryza sativa, Potamogeton pectinatus and Scirpus spp. are common in the south. The reviewed studies are based on the contents of different parts of the digestive system and on a variety of methods to quantify food items. The variations in sampling techniques and shortage of articles from the breeding season and some geographic regions highlight the need for future studies. In the future, it is important to standardize sampling techniques to improve the possibility to compare studies and to obtain a more representative view of the diet of dabbling ducks in Europe.

  • 40.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Elmberg, Johan
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Bidrar gäss och svanar  till övergödning av våtmarker?2018Ingår i: Fakta för förvaltare: gäss och svanar: kunskapssammanställning om bete, övergödning, smittspridning och skyddsjakt / [ed] Johan Elmberg & Johan Månsson, Stockholm: Naturvårdsverket , 2018, s. 33-47Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [sv]

    • Gäss och svanar förekommer idag i större antal nära fler människor än någonsin tidigare, i Sverige och i övriga Västeuropa.

    • De ökande antalen leder ibland till problem och konflikter. På jordbruksmark kan gäss och svanar orsaka kostsamma skador på oskördade grödor. Hårt bete kan också påverka naturlig växtlighet och då bli ett naturvårdsproblem.

    • Gäss och svanar är vegetarianer och äter enbart blad, stjälkar, frön och rotdelar från växter, både på land och i vatten.

    • Bete på växande grödor kan också skapa intressekonflikter i områden där gäss samlas i stora antal, till exempel vid skyddade och restaurerade våtmarker.

    • Samtidigt bidrar gässen med många ekosystemtjänster, bland andra i form av naturupplevelser, jakt och kött. GÄSS OCH SVANAR SOM NÄRINGSTRANSPORTÖRER

    • Gäss och svanar har en relativt sett näringsfattig kost och en ganska ineffektiv matsmältning. Därför måste de äta mycket och producerar följaktligen stora  mängder avföring.

    • Dessa fåglar hittar mycket av sin föda på land, men vilar en stor del av dygnet  på våtmarker, där de också bajsar.

    • Under höst, vinter och vår gör gäss och svanar omfattande dagliga förflyttningar  mellan födoplatser och viloplatser. De blir därmed naturliga transportörer av näringsämnen till våtmarker och sjöar.ÖVERGÖDNING I VATTENDRAG

    • Under häckningstiden på sommaren är de flesta gäss och svanar glest utspridda över stora områden, samtidigt som flera arter häckar i våtmarker och sjöar som är naturligt näringsfattiga. Under dessa omständigheter är fåglarnas näringstransport från land till vattenmiljöer en naturlig process som snarast bidrar till ett rikare växt- och djurliv.

    • Våtmarker där gäss och svanar samlas i stora antal under höst, vinter och vår  är dock sällan näringsfattiga, och många av dem har redan problem med över- gödning genom näringsläckage från jordbruksmark. Övergödning kan leda till  algblomning, försämrad vattenkvalitet och andra oönskade förändringar i våtmarks- ekosystemet.

    • I områden som redan har problem med övergödning kan gäss och svanar göra att problemen ökar. Särskilt känsliga är små vattensamlingar med begränsat till- och utflöde, men också de som sommartid har kraftig avdunstning i kombination med stora antal fåglar.

    • En betydande del av den samlade näringstillförseln till våtmarker sker under den tid på året då växterna är inaktiva och alltså inte tar upp näringsämnen. Detta leder till att de senare antingen sedimenterar (och frigörs en annan årstid), eller att de transporteras nedströms och kan orsaka övergödning där.

    • Ett räkneexempel visar att 2 000 gäss som uppehåller sig i en våtmark i fyra månader kan bidra med 160 kg kväve och 40–80 kg fosfor. I vilken mån detta är problematiskt beror på hur mycket samma område påverkas av näringsläckage från jordbruk och andra mänskliga källor.

    • Kunskapssammanställningen ger exempel på åtgärder man kan vidta för att öka eller minska en våtmarks attraktivitet för gäss och svanar.

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  • 41.
    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))
  • 42.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Englund, Göran
    Department of Ecology and Environmental Science, Umeå University.
    Pike predation affects breeding success and habitat selection of ducks2011Ingår i: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 56, nr 3, s. 579-589Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    1. Fish and ducks often belong to the same local food web, and several studies indicate that there is a general negative effect of fish on breeding ducks. This pattern has so far been addressed mainly within the framework of competition for common invertebrate prey, while predation by large fish as a force behind settlement and abundance patterns in ducks remains largely unknown. This is the first study to address the effect of fish predation on breeding ducks, isolated from that of competition, and the first experiment to explore the ability of ducks to identify and avoid lakes with high risk of fish predation. 2. We used a before-after control-impact design and 11 naturally fishless lakes. Waterfowl on the lakes were surveyed during the breeding season of 2005. Large adult pike (Esox lucius) were added to two lakes in early spring 2008, and waterfowl surveys were repeated on all 11 lakes. 3. Pike introduction did not affect the number of pairs on lakes during the nesting season in any of three focal duck species (mallard Anas platyrhynchos, teal Anas crecca, and goldeneye Bucephala clangula). During the brood-rearing season, however, there was a decrease in duck days in teal and goldeneye in lakes with pike, with similar trends observed in mallard. The number of goldeneye ducklings was also significantly lower in lakes with pike. We were unable to determine whether the response was attributable to direct pike predation or to broods leaving experimental lakes, but in either case, our study demonstrates high fitness costs for ducks breeding on lakes with pike. 4. The apparent inability of nesting ducks to detect pike and the clear fitness implications may influence the annual recruitment of ducks on a larger scale as pike are both common and widespread. Vegetation complexity and food abundance are likely to be of overriding importance when breeding ducks are choosing a nesting site. As pike have a strong influence on breeding birds, relying on vegetation and cues of food abundance, while ignoring indicators of predation risk from fish, could lead to lakes with pike acting as an ecological trap.

  • 43.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för hälsa och samhälle.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Englund, Göran
    Department of Ecology and Environmental Science, Umeå University.
    The effects of pike predation on lake use and reproductive success of ducks: an experimental study in boreal lakes2009Ingår i: Abstracts, 2nd Pan-European Duck Symposium, 2009, s. 36-Konferensbidrag (Refereegranskat)
    Ladda ner (pdf)
    SUMMARY01
  • 44.
    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)
  • 45.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Nummi, Petri
    Department of Forest Ecology, University of Helsinki.
    Pöysä, Hannu
    Finnish Game and Fisheries Research Institute, Joensuu Game and Fisheries Research.
    Sjöberg, Kjell
    Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, Umeå.
    Hatching in dabbling ducks and emergence in chironomids: a case of predator-prey synchrony?2009Ingår i: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 636, nr 1, s. 319-329Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    It has been hypothesized that dabbling ducks (Anas spp.) time breeding to coincide with annual regional peaks in emerging dipterans, especially Chironomidae, which are important prey for newly hatched ducklings. However, this hypothesis has never been evaluated in a replicated lake-level study, including year effects in emergence patterns. We collected duck and invertebrate data from 12 lakes during the nesting seasons 1989-1994 in a watershed in southern Finland. The oligotrophic study lakes are typical of the boreal Holarctic, as are the three focal duck species: mallard Anas platyrhynchos L., widgeon Anas penelope L and teal Anas crecca L. Hatching of ducklings showed a clear peak in relation to ambient phenology (annual ice-out date of lakes), whereas chironomid emergence was more erratic and showed no clear peak at the lake level, although total watershed-level emergence was somewhat higher before and long after the duck hatching peak. Thus, we find no evidence that ducklings hatch in synchrony with abundance peaks of emerging chironomids. There was large within-year temporal variation in chironomid emergence among lakes, but this was not correlated with ambient temperature. The rank of individual lakes with respect to the abundance of emerging chironomids was consistent among as well as within years, a predictability that ought to make adaptive lake choice by ducks possible. On the lake level, there was a positive correlation between the total amount of emerging chironomids and brood use. We argue that emergence patterns of chironomids on typical boreal lakes are neither compressed nor predictable enough to be a major selective force on the timing of egg-laying and hatching in dabbling ducks. Despite spatial (among-lake) patterns of abundance of emerging chironomids being predictable within and among years, the observed pattern of brood use suggests that other factors, e.g. habitat structure, also affect lake choice.

  • 46.
    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)
  • 47.
    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.

  • 48.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH).
    Hessel, Rebecca
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH).
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH).
    Geese as vectors of nitrogen and phosphorus to freshwater systems2016Ingår i: Inland Waters, ISSN 2044-2041, E-ISSN 2044-205X, Vol. 6, nr 1, s. 111-122Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many goose populations have increased dramatically over the past decades, which may influence inland waters used as roost sites. We reviewed the role of geese in the influx of nitrogen and phosphorus to freshwater systems. Several methods have been used to estimate guanotrophication impacts of geese. Water and sediment analysis have been conducted in areas of high and low geese presence; however, productive wetlands tend to attract more birds, and the causality is therefore ambiguous. Faecal addition experiments have attempted to estimate the impacts of droppings on water chemistry, sediments, algal growth, or invertebrate densities. The most common method of estimating goose guanotrophication is by extrapolation, usually based on multiplication of faecal production and its nutrient content. Based on such studies and those including information about daily migration patterns, we developed an approach to improve estimates of the nutrient contribution of geese. The relative role of geese in wetland eutrophication is also affected by the influx from alternative sources. The greatest guanotrophication impacts are likely found in areas with few alternative nutrient sources and with large goose flocks. Limited inflow and outflow of a freshwater system or a scarcity of wetland roosts may also increase problems at a local scale. Although several studies have looked at the impacts of geese on, for example, water chemistry or soil sediments, the effects are often smaller than expected, in part because no study to date has assessed the ecosystem response by including impacts on all levels, including water nutrient levels, nutrient sedimentation, chlorophyll content, and zooplankton response.

  • 49.
    Dessborn, Lisa
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Rönkä, M
    Arzel, C
    Elmberg, Johan
    Högskolan Kristianstad, Sektionen för lärande och miljö, Avdelningen för Naturvetenskap. Högskolan Kristianstad, Forskningsmiljön Man & Biosphere Health (MABH).
    Sinisorsanpoikaset välttelevät synnynnäisesti erityyppisiä petoja2016Ingår i: Soumen Riista, ISSN 0355-0656, Vol. 62, s. 43-54Artikel i tidskrift (Refereegranskat)
  • 50.
    Djerf, Henric
    et al.
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap. Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH).
    Elmberg, JohanHögskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Djerf, Henric (Medarbetare/bidragsgivare)
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap. Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH).
    Elmberg, Johan (Medarbetare/bidragsgivare)
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Jönsson, K. Ingemar (Medarbetare/bidragsgivare)
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Rehnstam-Holm, Ann-Sofi (Medarbetare/bidragsgivare)
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Söderquist, Pär (Medarbetare/bidragsgivare)
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Vought, Lena B. M. (Medarbetare/bidragsgivare)
    Högskolan Kristianstad, Fakulteten för naturvetenskap, Forskningsmiljön Man & Biosphere Health (MABH). Högskolan Kristianstad, Fakulteten för naturvetenskap, Avdelningen för miljö- och biovetenskap.
    Bioblitz i Arkelstorp 16-17 augusti 20192020Samlingsverk (redaktörskap) (Övrigt vetenskapligt)
    Abstract [sv]

    Arkelstorpsviken är den nordvästra delen av Oppmannasjön, som ären av Skånes största sjöar. Idén att genomföra en så kallad Bioblitzvid Arkelstorpsviken föddes under ett styrelsemöte i projektet "En viki Sjöriket Skåne" som är ett samarbete mellan Oppmanna Vånga Bygderåd och Högskolan Kristianstad. Projektets främsta syfte är att hitta en lösning på den kraftiga övergödningen i Arkelstorpsviken. Detta är ett ”Leader”-finansierat projekt, vilket innebär att stommen i projektetär lokal förankring. Det fanns röster i byn som kände att man gav området onödigt dåligt rykte genom att ständigt lyfta fram problemen med vattenstatusen i sjön. Under ett styrelsemöte 30 sep 2018 föddes iden att genom en Bioblitz lyfta fram de positiva värdena i och kring sjön. Den naturliga samarbetspartnern för detta projekt var forskningsmiljön MABH (Man & Biosphere Health) vid Högskolan Kristianstad,vars medlemmar tillsammans besitter en mycket bred biologisk kunskap.Med MABH i ryggen var alltså kompetensen säkrad för att genomföra en Bioblitz. Inbjudningar skickades ut till lokala naturorganisationerför att hitta ännu fler experter som kunde hjälpa till med särskilda artgrupper. Samtidigt jobbade man aktivt lokalt med att försöka engagera intresserad allmänhet. Inbjudningar och direktreklam skickades ut till samtliga hushåll med postadress Arkelstorp. I ett försök att synas genom mediebruset anordnades en tävling, som gick ut på att gissa antalet arter (taxa) som hittades under Bioblitzen. Två lokala företag ställde upp och första priset för den vuxna individ som gissade närmstvar en 3-rätters måltid på Bäckaskogs Slott. De yngre tävlande kunde vinna en kanotutflykt med familjen på Ivögården.

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