| 1. |
- Alanärä, Anders, et al.
(författare)
-
Utsättning av djur för jakt och fiske
- 2021
-
Bok (populärvet., debatt m.m.)abstract
- SLUs vetenskapliga råd för djurskydd har fått i uppdrag av Jordbruksverket att sammanställa aktuell forskning kring utsättning av djur för jakt och fiske samt att belysa eventuella kunskapsluckor på området. Uppdraget omfattar gräsand, rapphöna, fasan och laxfiskar. Bruket att föda upp fåglar och fiskar för utsättning i syfte att gynna jakt och fiske ifrågasätts inte sällan av etiska skäl, men den diskussionen ligger utanför fokus för denna rapport. Utsättning av fågel och fisk är en antropogen verksamhet som, till skillnad från många andra typer av mänsklig påverkan, syftar till att gynna arterna i fråga. Det kan handla om naturvårdsinsatser, att återinföra försvunna arter eller att på andra sätt berika ekosystemet, inte sällan med ökade möjligheter till jakt eller fiske som slutändamål. Ofta förbereds och åtföljs utsättningar av habitatförbättrande åtgärder som inte endast gynnar de utsatta individerna och deras artfränder, utan även har positiva konsekvenser för biologisk mångfald och ekosystemet i stort. I utarbetandet av regelverket knutet till utsättning av fågel och fisk är det viktigt att även beakta de positiva föresatserna och de konsekvenser som verksamheten kan medföra. Annars riskerar man att engagemang och incitament förloras, till men för biologisk mångfald och en rik och levande landsbygd.
|
|
| 2. |
- Bengtsson, Daniel, et al.
(författare)
-
Movements, Home-Range Size and Habitat Selection of Mallards during Autumn Migration
- 2014
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:6
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
| 3. |
-
Bioblitz i Arkelstorp 16-17 augusti 2019
- 2020
-
Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- 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.
|
|
| 4. |
- Champagnon, Jocelyn, et al.
(författare)
-
Assessing the genetic impact of massive restocking on wild mallard
- 2013
-
Ingår i: Animal Conservation. - : Wiley: 12 months. - 1367-9430 .- 1469-1795. ; 16:3, s. 295-305
-
Tidskriftsartikel (refereegranskat)abstract
- Captive-bred mallards Anas platyrhynchos have been released for hunting purposes at a very large scale in Europe since the mid-1970s. In spite of a potential genetic impact, the actual contribution of restocked mallards to the genome of the target population has received little attention. The genetic structure of modern wild mallards in the Camargue, Southern France, was assessed from two samples: one originating from shot birds in hunting bags and one from presumed wild ducks captured alive in a hunting-free reserve. Reference samples originated from five mallard farms, as well as from museum samples collected before the mid-1970s (i.e. before massive mallard releases started). Our results revealed that the genetic signature of wild wintering mallards has not changed significantly because museum and presumed wild samples from the Camargue hunting-free nature reserve were genetically similar, and clearly differentiated from the farm mallards. This suggests that mallard releases in the Camargue or elsewhere in France, although massive, have not actually translated into complete admixture of wild and captive genomes, most likely due to low survival of released birds once in the wild. Nevertheless, although genetic introgression of the wild population by captive-bred was contained, we found significant rates of hybridization between wild and captive-bred mallards in modern samples. This result suggests that long-term releases of captive-bred mallards, if carried on at such large scale, could compromise irreversibly the genetic structure and composition of European mallards. This work contributes to fill in the gap on the monitoring of the genetic consequences of large-scale game releases for exploitation.
|
|
| 5. |
- Champagnon, Jocelyn, et al.
(författare)
-
Assessing the genetic impact of massive restocking on wild mallard
- 2013
-
Ingår i: Animal Conservation. - : Wiley-Blackwell. - 1367-9430 .- 1469-1795. ; 16:3, s. 295-305
-
Tidskriftsartikel (refereegranskat)abstract
- Captive-bred mallards Anas platyrhynchos have been released for hunting purposes at a very large scale in Europe since the mid-1970s. In spite of a potential genetic impact, the actual contribution of restocked mallards to the genome of the target population has received little attention. The genetic structure of modern wild mallards in the Camargue, Southern France, was assessed from two samples: one originating from shot birds in hunting bags and one from presumed wild ducks captured alive in a hunting-free reserve. Reference samples originated from five mallard farms, as well as from museum samples collected before the mid-1970s (i.e. before massive mallard releases started). Our results revealed that the genetic signature of wild wintering mallards has not changed significantly because museum and presumed wild samples from the Camargue hunting-free nature reserve were genetically similar, and clearly differentiated from the farm mallards. This suggests that mallard releases in the Camargue or elsewhere inFrance, although massive, have not actually translated into complete admixture of wild and captive genomes, most likely due to low survival of released birds once in the wild. Nevertheless, although genetic introgression of the wild population by captive-bred was contained, we found significant rates of hybridization between wild and captive-bred mallards in modern samples. This result suggests that long-term releases of captive-bred mallards, if carried on at such large scale, could compromise irreversibly the genetic structure and composition of European mallards. This work contributes to fill in the gap on the monitoring of the genetic consequences of large-scale game releases for exploitation.
|
|
| 6. |
- Champagnon, Jocelyn, et al.
(författare)
-
Silent domestication of wildlife in the Anthropocene : The mallard as a case study
- 2023
-
Ingår i: Biological Conservation. - : Elsevier BV. - 0006-3207. ; 288
-
Tidskriftsartikel (refereegranskat)abstract
- In the Anthropocene, human activities have been a dominant force affecting wildlife, natural habitats, and climate worldwide. Over time, increasing incidences of wildlife-human interactions may have positive outcomes for some generalist species, but studies continue to uncover that most predictably these generalist wild species also suffer from such interactions. In particular, the line between domestic and wild continues to blur as gene flow between these groups intensifies in the Anthropocene. We explore the meaning of wildness, focusing on the mallard, currently the most abundant duck species in the world. Mallard has been connected to humans for tens of thousands of years. Considered an exemplary generalist species with the capacity to adapt to rapidly changing environments, evidence gathered from a variety of disciplines suggests that some management efforts over the last centuries have resulted in the deterioration of the mallard's prolific nature, and that the apparent success in terms of current population size and wide distribution could mask a genetic collapse. Highlighting warning signs from the mallard system, in this Perspectives paper we discuss how active management of habitats and populations runs the risk of compromising species' wildness, and we suggest precautionary and counter-measures in the context of species management and conservation.
|
|
| 7. |
- Dalby, Lars, et al.
(författare)
-
The status of the Nordic populations of the Mallard (Anas platyrhynchos) in a changing world
- 2013
-
Ingår i: Ornis Fennica. - : Finnish Omithological Soc. - 0030-5685. ; 90:1, s. 2-15
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
| 8. |
- Dalby, Lars, et al.
(författare)
-
The status of the Nordic populations of the Mallard (Anas platyrhynchos) in a changing world
- 2013
-
Ingår i: Ornis Fennica. - : University of Helsinki. - 0030-5685. ; 90:1, s. 2-15
-
Tidskriftsartikel (refereegranskat)abstract
- Dabbling ducks (Anas spp.) are important migratory 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 the Mallard, 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 productivity measures 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.
|
|
| 9. |
|
|
| 10. |
- Elmberg, Johan, et al.
(författare)
-
Farmed European mallards are genetically different and cause introgression in the wild population following releases
- 2016
-
Konferensbidrag (refereegranskat)abstract
- The practice of restocking already viable populations to increase harvest potential has since long been common in forestry, fisheries and wildlife management. The potential risks of restocking native species have long been overshadowed by the related issue of invasive alien species. However, during the last decade releases of native species with potentially non-native genome have received more attention. A suitable model to study genetic effects of large-scale releases of native species is the Mallard Anas platyrhynchos, being the most widespread duck in the world, largely migratory, and an important quarry species. More than 3 million unfledged hatchlings are released each year around Europe to increase local harvest. The aims of this study were to determine if wild and released farmed Mallards differ genetically, if there are signs of previous or ongoing introgression between wild and farmed birds, and if the genetic structure of the wild Mallard population has changed since large-scale releases started in Europe in the 1970s. Using 360 Single Nucleotide Polymorphisms (SNPs) we found that the genetic structure differed among historical wild, present-day wild, and farmed Mallards in Europe. We also found signs of introgression in the wild Mallard population, that is, individuals with a genetic background of farmed stock are part of the present free-living population. Although only a small proportion of the released Mallards appears to survive to merge with the free-living breeding population, their numbers are still so large that the genetic impact may have significance for the wild population in terms of individual survival and longterm fitness.
|
|
| 11. |
- Elmberg, Johan, et al.
(författare)
-
Farmed European mallards are genetically different and cause introgression in the wild population following releases
- 2016
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The practice of restocking already viable populations to increase harvest potential has since long been common in forestry, fisheries and wildlife management. The potential risks of restocking native species have long been overshadowed by the related issue of invasive alien species. However, during the last decade releases of native species with potentially non-native genome have received more attention. A suitable model to study genetic effects of large-scale releases of native species is the Mallard Anas platyrhynchos, being the most widespread duck in the world, largely migratory, and an important quarry species. More than 3 million unfledged hatchlings are released each year around Europe to increase local harvest. The aims of this study were to determine if wild and released farmed Mallards differ genetically, if there are signs of previous or ongoing introgression between wild and farmed birds, and if the genetic structure of the wild Mallard population has changed since large-scale releases started in Europe in the 1970s. Using 360 Single Nucleotide Polymorphisms (SNPs) we found that the genetic structure differed among historical wild, present-day wild, and farmed Mallards in Europe. We also found signs of introgression in the wild Mallard population, that is, individuals with a genetic background of farmed stock are part of the present free-living population. Although only a small proportion of the released Mallards appears to survive to merge with the free-living breeding population, their numbers are still so large that the genetic impact may have significance for the wild population in terms of individual survival and longterm fitness.
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
- Elmberg, Johan, 1960-, et al.
(författare)
-
Hur utsatta är utsatta änder?
- 2012
-
Ingår i: Vår fågelvärld. - 0042-2649. ; 71:2, s. 40-42
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Utsättningar av djur och växter har förekommit mycket länge. Slottens svandammar har kommit till av detta skäl, godsen har satt ut jaktbart vilt. Jordbruk och skogsbruk bygger på idén att plantera ut för att sedan skörda, och även naturvården ägnar sig åt ”stödutplanteringar”. Ingen fågelart sätts ut i så stora antal som gräsanden. Men vad är det för änder det handlar om? Vilka blir effekterna?
|
|
| 15. |
- Elmberg, Johan, et al.
(författare)
-
Hur utsatta är utsatta änder?
- 2012
-
Ingår i: Vår fågelvärld. - 0042-2649. ; 71:2, s. 40-42
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Utsättningar av djur och växter har förekommit mycket länge. Slottens svandammar har kommit till av detta skäl, godsen har satt ut jaktbart vilt. Jordbruk och skogsbruk bygger på idén att plantera ut för att sedan skörda, och även naturvården ägnar sig åt ”stödutplanteringar”. Ingen fågelart sätts ut i så stora antal som gräsanden. Men vad är det för änder det handlar om? Vilka blir effekterna?
|
|
| 16. |
- Elmberg, Johan, 1960-, et al.
(författare)
-
Utsatta änder inte som vilda
- 2018
-
Ingår i: Svensk Jakt. ; :10, s. 51-51
-
Tidskriftsartikel (populärvet., debatt m.m.)
|
|
| 17. |
- Elmberg, Johan, et al.
(författare)
-
Utsatta änder inte som vilda
- 2018
-
Ingår i: Svensk jakt. - 0039-6583. ; :10, s. 51-51
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 18. |
- Elmberg, Johan, 1960-, et al.
(författare)
-
Vad händer med utsatta änder?
- 2012
-
Ingår i: Svensk Jakt. - 0039-6583. ; 150:8, s. 88-89
-
Tidskriftsartikel (populärvet., debatt m.m.)
|
|
| 19. |
- Elmberg, Johan, et al.
(författare)
-
Vad händer med utsatta änder?
- 2012
-
Ingår i: Svensk jakt. - 0039-6583. ; 150:8, s. 88-89
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 20. |
|
|
| 21. |
|
|
| 22. |
- Guillemain, M, et al.
(författare)
-
Mallard (Anas platyrhynchos Linnaeus, 1758)
- 2020
-
Ingår i: Invasive birds. - Wallingford : CABI International. - 9781789242065 ; , s. 194-199
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
|
|
| 23. |
|
|
| 24. |
- Gunnarsson, Gunnar, et al.
(författare)
-
The hub of the wheel or hitchhikers? : The potential influence of large avian herbivores on other trophic levels in wetland ecosystems
- 2024
-
Ingår i: Hydrobiologia. - : Springer. - 0018-8158 .- 1573-5117. ; 851, s. 107-127
-
Tidskriftsartikel (refereegranskat)abstract
- Goose and swan populations have increased concurrently with environmental degradation of wetlands, such as eutrophication, vegetation losses, and decrease in biodiversity. An important question is whether geese and swans contribute to such changes or if they instead benefit from them. We collected data from 37 wetlands in southern Sweden April - July 2021 to study relationships between geese, swans and other waterbird guilds, macrophytes, invertebrates, as well as physical and water chemistry variables. Neither goose nor swan abundance was negatively correlated with other trophic levels (abundance, richness, or cover). On the contrary, goose or swan abundances were positively related to abundances of surface and benthic feeding waterbirds, cover of specific macrophytes, and to invertebrate richness and abundance. Moreover, invertebrates (number of taxa or abundance) were positively associated with abundance of several waterbird guilds and total phosphorous with surface feeders, whereas water colour was positively (surface feeders) or negatively (benthic feeders) related. We conclude that waterbirds are more abundant in productive wetlands and that geese and swans do not show clear deleterious effects on other trophic levels included in this study. However, patterns may be masked at the species level, which should be addressed in further studies, complemented with experimental studies of grazing impact.
|
|
| 25. |
|
|
| 26. |
|
|
| 27. |
|
|
| 28. |
- Kraus, R.H.S., et al.
(författare)
-
Freigelassenes Federwild führt zu kontinent-weiter genetischer Introgression : die sich ändernde genetische Landschaft der Stockente Anas platyrhynchos in Europa
- 2015
-
Konferensbidrag (refereegranskat)abstract
- 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.
|
|
| 29. |
|
|
| 30. |
|
|
| 31. |
|
|
| 32. |
|
|
| 33. |
- Lavretsky, Philip, et al.
(författare)
-
The meaning of wild : Genetic and adaptive consequences from large-scale releases of domestic mallards
- 2023
-
Ingår i: Communications Biology. - : Springer Nature. - 2399-3642. ; 6:1
-
Tidskriftsartikel (refereegranskat)abstract
- The translocation of individuals around the world is leading to rising incidences of anthropogenic hybridization, particularly between domestic and wild congeners. We apply a landscape genomics approach for thousands of mallard (Anas platyrhynchos) samples across continental and island populations to determine the result of over a century of supplementation practices. We establish that a single domestic game-farm mallard breed is the source for contemporary release programs in Eurasia and North America, as well as for established feral populations in New Zealand and Hawaii. In particular, we identify central Europe and eastern North America as epicenters of ongoing anthropogenic hybridization, and conclude that the release of game-farm mallards continues to affect the genetic integrity of wild mallards. Conversely, self-sustaining feral populations in New Zealand and Hawaii not only show strong differentiation from their original stock, but also signatures of local adaptation occurring in less than a half-century since game-farm mallard releases have ceased. We conclude that 'wild' is not singular, and that even feral populations are capable of responding to natural processes. Although considered paradoxical to biological conservation, understanding the capacity for wildness among feral and feral admixed populations in human landscapes is critical as such interactions increase in the Anthropocene.
|
|
| 34. |
|
|
| 35. |
|
|
| 36. |
- Pöysä, Hannu, et al.
(författare)
-
Harvest mortality in North American mallards : a reply to Sedinger and Herzog
- 2013
-
Ingår i: Journal of Wildlife Management. - : Wiley-Blackwell. - 0022-541X .- 1937-2817. ; 77:4, s. 653-654
-
Tidskriftsartikel (refereegranskat)abstract
- Sedinger and Herzog (2012) evaluated the evidence for the impact harvest mortality may have on North American duck populations. While doing that, they questioned our review (Pöysä et al. 2004) and conclusion that harvest mortality in North American mallards (Anas platyrhynchos) may have shifted from compensatory to additive over the period from the 1960s to the 1980s. In this reply, we correct Sedinger and Herzog's misrepresentations of our 2004 paper and argue that our interpretations of the results published at that time have not been invalidated.
|
|
| 37. |
- Söderquist, Pär, et al.
(författare)
-
Admixture between released and wild game birds: a changing genetic landscape in European mallards (Anas platyrhynchos)
- 2017
-
Ingår i: European Biophysics Journal. - : Springer Verlag (Germany). - 0175-7571 .- 1432-1017. ; 63
-
Tidskriftsartikel (refereegranskat)abstract
- Disruption of naturally evolved spatial patterns of genetic variation and local adaptations is a growing concern in wildlife management and conservation. During the last decade, releases of native taxa with potentially non-native genotypes have received increased attention. This has mostly concerned conservation programs, but releases are also widely carried out to boost harvest opportunities. The mallard, Anas platyrhynchos, is one of few terrestrial migratory vertebrates subjected to large-scale releases for hunting purposes. It is the most numerous and widespread duck in the world, yet each year more than three million farmed mallard ducklings are released into the wild in the European Union alone to increase the harvestable population. This study aimed to determine the genetic effects of such large-scale releases of a native species, specifically if wild and released farmed mallards differ genetically among subpopulations in Europe, if there are signs of admixture between the two groups, if the genetic structure of the wild mallard population has changed since large-scale releases began in the 1970s, and if the current data matches global patterns across the Northern hemisphere. We used Bayesian clustering (Structure software) and Discriminant Analysis of Principal Components (DAPC) to analyze the genetic structure of historical and present-day wild (n = 171 and n = 209, respectively) as well as farmed (n = 211) mallards from six European countries as inferred by 360 single-nucleotide polymorphisms (SNPs). Both methods showed a clear genetic differentiation between wild and farmed mallards. Admixed individuals were found in the present-day wild population, implicating introgression of farmed genotypes into wild mallards despite low survival among released farmed mallards. Such cryptic introgression would alter the genetic composition of wild populations and may have unknown long-term consequences for conservation.
|
|
| 38. |
- Söderquist, Pär, et al.
(författare)
-
Admixture between released and wild game birds: a changing genetic landscape in European mallards (Anas platyrhynchos)
- 2017
-
Ingår i: European Biophysics Journal. - : Springer Verlag. - 0175-7571 .- 1432-1017. ; 63:6
-
Tidskriftsartikel (refereegranskat)abstract
- Disruption of naturally evolved spatial patterns of genetic variation and local adaptations is a growing concern in wildlife management and conservation. During the last decade, releases of native taxa with potentially non-native genotypes have received increased attention. This has mostly concerned conservation programs, but releases are also widely carried out to boost harvest opportunities. The mallard, Anas platyrhynchos, is one of few terrestrial migratory vertebrates subjected to large-scale releases for hunting purposes. It is the most numerous and widespread duck in the world, yet each year more than three million farmed mallard ducklings are released into the wild in the European Union alone to increase the harvestable population. This study aimed to determine the genetic effects of such large-scale releases of a native species, specifically if wild and released farmed mallards differ genetically among subpopulations in Europe, if there are signs of admixture between the two groups, if the genetic structure of the wild mallard population has changed since large-scale releases began in the 1970s, and if the current data matches global patterns across the Northern hemisphere. We used Bayesian clustering (Structure software) and Discriminant Analysis of Principal Components (DAPC) to analyze the genetic structure of historical and present-day wild (n = 171 and n = 209, respectively) as well as farmed (n = 211) mallards from six European countries as inferred by 360 single-nucleotide polymorphisms (SNPs). Both methods showed a clear genetic differentiation between wild and farmed mallards. Admixed individuals were found in the present-day wild population, implicating introgression of farmed genotypes into wild mallards despite low survival among released farmed mallards. Such cryptic introgression would alter the genetic composition of wild populations and may have unknown long-term consequences for conservation.
|
|
| 39. |
|
|
| 40. |
- Söderquist, Pär, et al.
(författare)
-
Effects of released farmed mallards on species richness of breeding waterbirds and amphibians in natural, restored and constructed wetlands
- 2021
-
Ingår i: Wildlife Biology. - 0909-6396 .- 1903-220X. ; 2021, s. 1-9
-
Tidskriftsartikel (refereegranskat)abstract
- Common practices in current game management are wetland restoration and creation, as well as releases of quarry species. We studied the impact of releases of mallard ducklings on species richness of wild waterbirds and amphibians on three types of wetlands: natural, constructed and restored. Data on species richness, macrophyte cover and water characteristics (total phosphorous and pH) were collected at 32 sites in an agricultural landscape in southern Sweden. In total, 14 species of waterbirds were recorded, ranging from zero to seven per wetland and survey. Amphibians were present in 24 of the 32 wetlands; in total five species were found, ranging from zero to three per wetland. By using generalized linear modelling we found that wetland type best predicted waterbird species richness. Constructed wetlands had significantly more waterbird species, regardless of whether they were used for mallard releases or not. There were breeding amphibians in 62% of natural, 100% of restored and 77% of constructed wetlands. Breeding amphibians were present in 84% of wetlands without, and in 62% of wetlands with releases. However, included variables did not explain amphibian species richness in the wetlands. Releasing large numbers of mallards on a wetland and providing food ad libitum is likely to affect water quality, nutrient availability and predation pressure. Indeed, phosphorous levels were significantly higher in release wetlands, but no differences were found between wetland types.This means that mallard releases may increase nutrient loads in environments that are already eutrophied. However, in our study system releases did not influence species richness of waterbirds and amphibians locally. Constructing wetlands for mallard releases can thus have positive local effects on species richness.
|
|
| 41. |
- Söderquist, Pär, et al.
(författare)
-
Effects of released farmed mallards on species richness of breeding waterbirds and amphibians in natural, restored and constructed wetlands
- 2021
-
Ingår i: Wildlife Biology. - : Nordic Council for Wildlife Research. - 0909-6396. ; 2021:3, s. 1-9
-
Tidskriftsartikel (refereegranskat)abstract
- Common practices in current game management are wetland restoration and creation, as well as releases of quarry species. We studied the impact of releases of mallard ducklings on species richness of wild waterbirds and amphibians on three types of wetlands: natural, constructed and restored. Data on species richness, macrophyte cover and water characteristics (total phosphorous and pH) were collected at 32 sites in an agricultural landscape in southern Sweden. In total, 14 species of waterbirds were recorded, ranging from zero to seven per wetland and survey. Amphibians were present in 24 of the 32 wetlands; in total five species were found, ranging from zero to three per wetland. By using generalized linear modelling we found that wetland type best predicted waterbird species richness. Constructed wetlands had significantly more waterbird species, regardless of whether they were used for mallard releases or not. There were breeding amphibians in 62% of natural, 100% of restored and 77% of constructed wetlands. Breeding amphibians were present in 84% of wetlands without, and in 62% of wetlands with releases. However, included variables did not explain amphibian species richness in the wetlands. Releasing large numbers of mallards on a wetland and providing food ad libitum is likely to affect water quality, nutrient availability and predation pressure. Indeed, phosphorous levels were significantly higher in release wetlands, but no differences were found between wetland types.This means that mallard releases may increase nutrient loads in environments that are already eutrophied. However, in our study system releases did not influence species richness of waterbirds and amphibians locally. Constructing wetlands for mallard releases can thus have positive local effects on species richness.
|
|
| 42. |
- Söderquist, Pär, et al.
(författare)
-
Effekter av utsättningar av farmade änder ämnade för jakt
- 2018
-
Ingår i: Man and Biosphere Health –. - Kristianstad : Högskolan Kristianstad. - 9789187973352 ; , s. 41-47
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- I över 40 år har det i Sverige pågått ett storskaligt, ekologiskt experiment där hundratusentals gräsänder årligen har fötts upp i fångenskap och satts ut i våtmarker för att öka på den jaktbara populationen. Genom uppfödning i fångenskap riskerar man att de farmade gräsänderna blir annorlunda gentemot de vilda. För att studera effekterna på den vilda populationen av dessa utsättningar startades 2010 ett doktorandprojekt finansierat av Naturvårdsverket. Projektet kom fram till att farmade änder skiljer sig i beteende och utseende mot de vilda. Det går även att genetiskt skilja på farmade och vilda gräsänder. Ett nytt projekt startades 2017 för att vidare studera effekter av utsättningar, nu även på miljön och den biologiska mångfalden där änderna sätts ut. Projekten om effekter av utsättningar av farmade änder involverar forskare från olika lärosäten i Sverige, men också från flera olika europeiska länder. Ett nära samarbete med olika lokala privata aktörer som uppfödare, markägare, jägare och viltmästare samt större organisationer somViltmästareförbundet och Svenska Jägareförbundet är avgörande för projektens framgång. Att kommuniceraresultaten på så väl vetenskapliga konferenser som för icke akademiker involverade i projekten samt i undervisning på Högskolan Kristianstad och på gymnasieskolor har hela tiden varit en målsättning. Projekten har också en tydlig plats i forskningsmiljön MABH vars kompetenser inom t.ex. vattenvård, sjukdomsspridning och landskapsutnyttjande kanknytas till projekten.
|
|
| 43. |
- Söderquist, Pär, et al.
(författare)
-
Effekter av utsättningar av farmade änder ämnade för jakt
- 2018
-
Ingår i: Man and Biosphere Health –. - Kristianstad : Högskolan Kristianstad. ; , s. 41-47
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- I över 40 år har det i Sverige pågått ett storskaligt, ekologiskt experiment där hundratusentals gräsänder årligen har fötts upp i fångenskap och satts ut i våtmarker för att öka på den jaktbara populationen. Genom uppfödning i fångenskap riskerar man att de farmade gräsänderna blir annorlunda gentemot de vilda. För att studera effekterna på den vilda populationen av dessa utsättningar startades 2010 ett doktorandprojekt finansierat av Naturvårdsverket. Projektet kom fram till att farmade änder skiljer sig i beteende och utseende mot de vilda. Det går även att genetiskt skilja på farmade och vilda gräsänder. Ett nytt projekt startades 2017 för att vidare studera effekter av utsättningar, nu även på miljön och den biologiska mångfalden där änderna sätts ut. Projekten om effekter av utsättningar av farmade änder involverar forskare från olika lärosäten i Sverige, men också från flera olika europeiska länder. Ett nära samarbete med olika lokala privata aktörer som uppfödare, markägare, jägare och viltmästare samt större organisationer somViltmästareförbundet och Svenska Jägareförbundet är avgörande för projektens framgång. Att kommuniceraresultaten på så väl vetenskapliga konferenser som för icke akademiker involverade i projekten samt i undervisning på Högskolan Kristianstad och på gymnasieskolor har hela tiden varit en målsättning. Projekten har också en tydlig plats i forskningsmiljön MABH vars kompetenser inom t.ex. vattenvård, sjukdomsspridning och landskapsutnyttjande kanknytas till projekten.
|
|
| 44. |
- Söderquist, Pär, et al.
(författare)
-
Evaluation of Nutritional Quality and Sensory Parameters of Meat from Mallard and Four Species of Wild Goose
- 2022
-
Ingår i: Foods. - : MDPI Multidisciplinary Digital Publishing Institute. - 2304-8158. ; 11:16, s. 1-13
-
Tidskriftsartikel (refereegranskat)abstract
- Future challenges concerning protein supply for food and feed include the management of all currently available resources. In Sweden, wildfowl are hunted for several reasons, one of which is to protect growing crops. In this study, meat from wild geese and mallard was evaluated with respect to its quality and sensory parameters. The most pronounced sensory differences were between meat from the barnacle goose and the Canada goose and between meat from mallards that were farmed and born wild. This study also provides measurements of values for the nutritional and heavy metal contents of the meat from these wildfowl species in order to elucidate their possible use as modern foods.
|
|
| 45. |
|
|
| 46. |
|
|
| 47. |
- Söderquist, Pär
(författare)
-
Large-scale releases of native species : the mallard as a predictive model system
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human alteration of natural systems, and its consequences are of great concern and the impact on global ecosystems is one of the biggest threats that biodiversity stands before. Translocations of invasive species, as well as intraspecific contingents with non-native genotypes, whether they are deliberate or unintentional, are one such alteration and its consequences are continuously being assessed. The mallard (Anas platyrhynchos) is the most numerous and widespread duck in the world and a flagship in wetland conservation. It is also an important game species which is heavily restocked for hunting purposes, especially in Europe where over three million ducklings are released every year. Because of its hunted status, its abundance, and the number of released individuals, it can serve as a model species to study effects of releases, both for conservation and restocking for hunting, on wild populations. In this thesis the status of the mallard was assessed in the Nordic countries and the effects of releases on the wild populations were studied by mining historical ringing data, comparing morphology of present-day wild, farmed, and historical mallards, and analyzing phylogeography of wild and farmed mallards in Europe. The status of the mallard population in the Nordic countries are generally good, however, a joint effort of European countries is needed to monitor and manage the population. A significant difference between wild and farmed mallards concerning longevity, migration, bill morphology and genetic structure was also found, together with signs of cryptic introgression of farmed genotypes in the wild population with potential fitness reduction as a result. The effect is however limited by that only a fraction of released farmed mallards reach the breeding season due to low survival. A natural captive environment is crucial to keep individuals wild-like with high survival rates after release. However, with an introgression of potentially maladapted farmed genotypes leading to a reduction in fitness, a low survival of released mallards would favor the wild population. A legislative change regarding obligation to report numbers, provenance, and release sites of farmed mallard should be considered, together with practical solutions of ringing and genetic monitoring of released mallards.
|
|
| 48. |
- Söderquist, Pär
(författare)
-
Large-scale releases of native species: the mallard as a predictive model system
- 2015
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human alteration of natural systems, and its consequences are of great concern and the impact on global ecosystems is one of the biggest threats that biodiversity stands before. Translocations of invasive species, as well as intraspecific contingents with non-native genotypes, whether they are deliberate or unintentional, are one such alteration and its consequences are continuously being assessed. The mallard (Anas platyrhynchos) is the most numerous and widespread duck in the world and a flagship in wetland conservation. It is also an important game species which is heavily restocked for hunting purposes, especially in Europe where over three million ducklings are released every year. Because of its hunted status, its abundance, and the number of released individuals, it can serve as a model species to study effects of releases, both for conservation and restocking for hunting, on wild populations. In this thesis the status of the mallard was assessed in the Nordic countries and the effects of releases on the wild populations were studied by mining historical ringing data, comparing morphology of present-day wild, farmed, and historical mallards, and analyzing phylogeography of wild and farmed mallards in Europe. The status of the mallard population in the Nordic countries are generally good, however, a joint effort of European countries is needed to monitor and manage the population. A significant difference between wild and farmed mallards concerning longevity, migration, bill morphology and genetic structure was also found, together with signs of cryptic introgression of farmed genotypes in the wild population with potential fitness reduction as a result. The effect is however limited by that only a fraction of released farmed mallards reach the breeding season due to low survival. A natural captive environment is crucial to keep individuals wild-like with high survival rates after release. However, with an introgression of potentially maladapted farmed genotypes leading to a reduction in fitness, a low survival of released mallards would favor the wild population. A legislative change regarding obligation to report numbers, provenance, and release sites of farmed mallard should be considered, together with practical solutions of ringing and genetic monitoring of released mallards.
|
|
| 49. |
- Söderquist, Pär, et al.
(författare)
-
Local movements of farmed-released versus wild mallards Anas platyrhynchos in fall
- 2024
-
Ingår i: Wildlife Biology. - : Nordic Council for Wildlife Research. - 0909-6396.
-
Tidskriftsartikel (refereegranskat)abstract
- Releasing farmed mallards into the wild is a common practice in wildlife management worldwide, involving millions of birds annually, and is mainly carried out to increase hunting opportunities. Ringing and previous research show that released mallards have low survival also outside the hunting season, and that survivors may compromise migration habits, morphology, and adaptations of the wild population. Detailed local movements of released mallards have not been studied before, despite the importance of spatiotemporal patterns for understanding the impact of releases and their utility for hunting. We studied local movements in August–October of 11 wild and 44 released mallards caught in the same wetland in southern Sweden and provided with GPS tags. Wild mallards moved longer distances than farmed, over the whole diel cycle, as well as during three out of four separate periods of the day (dawn, day, and dusk). Mallards of both origins moved the longest distances during dusk and dawn, and the shortest during the night. Males and females did not differ significantly in distance moved, regardless of origin (wild versus farmed). Our study demonstrates large differences in spatiotemporal movement patterns between wild and farmed mallards. The typical day of wild mallards included movements between wetlands in the landscape, likely to foraging sites known from previous experience. However, wild mallards frequently returned to the study wetland, probably attracted by supplementary bait. On the other hand, farmed mallards seldom left the study wetland, despite the possibility of accompanying wild birds to other sites. The sedentary behavior of farmed mallards and the fact that wild birds come to join them are both beneficial for hunting purposes. Limited movements of farmed mallards, together with their low survival, could also be positive as they limit hybridization between wild and farmed mallards, as well as dispersal of nutrients.
|
|
| 50. |
- Söderquist, Pär, et al.
(författare)
-
Longevity and migration distance differ between wild and hand-reared mallards Anas platyrhynchos in Northern Europe
- 2013
-
Ingår i: European Journal of Wildlife Research. - : Springer Verlag (Germany). - 1612-4642 .- 1439-0574. ; 59:2, s. 150-166
-
Tidskriftsartikel (refereegranskat)abstract
- The mallard Anas platyrhynchos is the world’s most widespread and numerous dabbling duck. It is also farmed and released to the wild by the millions each year, but the effects of this on wild populations remain little studied. By using historical national ringing–recovery data from Sweden and Finland, we here address three predictions based on previous studies: (1) longevity is higher in wild than in hand-reared mallards, (2) wild mallards migrate longer than hand-reared, and (3) migration distance in wild ducks surviving long enough to start fall migration has decreased over the last 50 years. Indeed, wild mallards lived longer than hand-reared (19 versus 9 months in Swedish birds and 13 versus 4 months in Finnish birds). Compared to wild mallards, a smaller proportion of hand-reared birds survived long enough to have the chance to enter the wild breeding population; less than 25 % of the Swedish birds and less than 10 % of the Finnish birds lived a year or longer. Wild birds migrated farther than hand-reared (mean distance in Swedish birds, 676 versus 523 km; in Finnish birds, 1,213 versus 157 km), a pattern caused by both shorter life span and lower migration speed in hand-reared birds. Mean migration distance in wild Swedish mallards was 787 km in 1947–1972 but 591 km in 1977–1993. This difference was not statistically significant, though, possibly due to the limited sample size and lack of data from the last two decades. In general, our study provides a conservative test of the predictions addressed, calling for more research about the consequences of restocking duck populations.
|
|
