| 1. |
- Edenius, Lars, et al.
(författare)
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Referensområden som verktyg för viltförvaltningsunderlag
- 2019
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Ingår i: Fakta. Skog. - 1400-7789.
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Annan publikation (populärvet., debatt m.m.)abstract
- Referensområden är områden där vi följer populationer av älg och andra viltarter, samt förändringar i landskapet, mer intensivt.Referensområden är viktiga för att utveckla övervakningsmetoder och skaffa sig bra kunskap om hur systemet fungerar, för utbildning, samt som demonstrationsområden.Referensområden förväntas bli en viktig komponent i den nya ekosystembaserade viltförvaltningen.Slaktvikter, reproduktionsdata, åldersstruktur, älgtäthet, fodermängder, betestryck och skogsskador är exempel på data som är relevanta att samla in i referensområden för den nya älgförvaltningens behov.SLU har flera områden och försöksparker som kan utvecklas till nationella referensområden.Fördjupad övervakning inom referensområden är ett viktigt komplement till förvaltningsinventeringar inom miljöanalys och viltövervakning.
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| 2. |
- Hofmeester, Tim, et al.
(författare)
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Övervakning av vissa mindre däggdjur : Metoder och pågående övervakning
- 2023
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Det är grundläggande för all viltförvaltning att veta hur många individer det finns av olika arter, och hur antalen förändras över tid. Sådan information samlas in genom olika former av inventeringsmetoder inom ramen för viltövervakningen. Naturvårdsverket har givit Sveriges lantbruksuniversitet (SLU) i uppdrag att ta fram en kunskapsöversikt över befintliga övervakningsmetoder och -system för de mindre däggdjursarter som jagas under allmän jakttid, samt de främmande arterna mink och vildkanin. Därutöver omfattar uppdraget även smågnagare, i och med deras betydelse för viktiga processer i ekosystemen. Rapporten utgör en del i ett pågående arbete att utreda möjligheterna för en integrerad viltövervakning i framtiden. Med undantag för smågnagare saknas riktade övervakningsprogram för arterna som tas upp i rapporten. Därmed baseras dagens kunskap främst på data från Artportalen samt avskjutningsstatistik, i bägge fallen insamlade genom frivilliga insatser med begränsade möjligheter till kvalitetssäkring. Andra data än antal individer som observerats, fångats eller fällts saknas i huvudsak. Genom att data från olika förvaltningsprojekt på lokal och regional skala också läggs in i Artportalen kan befintliga data både från allmänheten och den offentliga förvaltningen samlas och analyseras på ett enhetligt sätt. Så sker redan till viss del, men det finns möjligheter att utöka samordningen av insamlade data. Nya metoder erbjuder helt nya möjligheter att samla in kvalitetssäkrade data både för förekomst och för olika beteenden, dels genom kontrollerade övervakningsprogram dels genom bilder från allmänheten. Utvecklingen av viltkameror som tar bilder automatiskt när djur visar sig är på väg att revolutionera viltövervakningen. Det gäller särskilt djur som är nattaktiva eller svåra att följa av andra skäl. På motsvarande vis innebär möjligheten att ta bilder genom tubkikare att observationer kan kvalitetssäkras. Även utvecklingen av miljö-DNA som övervakningsmetod erbjuder nya möjligheter i framtiden. Parallellt med den tekniska utvecklingen tas allt mer komplexa statistiska metoder fram, som kan kombinera datakällor för att öka både precision och noggrannhet av populationsskattningar. Ny teknik och nya analysmetoder erbjuder en stor potential till förbättrad viltövervakning på kostnadseffektiva sätt. Dessa metoder behöver dock fortfarande kvalitetssäkras genom att jämföras med mer traditionella metoder, samt kalibreras för att möjliggöra att bygga vidare på befintliga tidsserier. Sammantaget är det tydligt att det idag saknas helhetsgrepp för övervakningen av mindre däggdjur. Samtidigt erbjuder ny teknik och nya metoder helt nya möjligheter att övervaka arter med olika ekologi kostnadseffektivt. Därmed möjliggörs en integrerad viltövervakning på ett helt nytt sätt.
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| 3. |
- Neumann, Wiebke, et al.
(författare)
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GPS-märkt klövvilt i Nordmalings studieområde 2017-2021 – Fördelning, rörelse, livsmiljö och överlevnad
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I Sverige är Nordmaling ett av få områden på så nordlig breddgrad där flera olika klövviltarter (d v s älg, rådjur, kronhjort och dovhjort, såväl som ren och mufflon) förekommer i större omfattning. Därmed utgör Nordmaling ett utmärkt referensområde att studera hur olika klövviltarter påverkar varandra och den omgivande miljön (studier om ekosystempåverkan) under nordiska förhållanden. Under perioden mars 2017 till mars 2021 märktes 27 vuxna älgkor, 23 rådjur (13 getter, 10 bockar) och 8 kronhindar med GPS-halsband. Totalt föddes 113 kalvar av 27 kor under studieperioden. Sommaröverlevnad av GPS-kornas årskalvar låg i genomsnitt på 88 % och efter jakten var 45% av de födda kalvarna vid liv. Antal kalvar som sköts under jakten skiftade mycket mellan åren och överlevnad under jakten låg i medel på 52%. Alla arter visade en dygnsrytm i sitt aktivitetsmönster med två aktivitetstoppar – en under tidig morgon och en senare på eftermiddag/kvälle. För älgkorna kunde vi se både vandringsälgar och stationära älgar. Rådjuren och kronhindarna visade inget tydligt vandringsbeteende som älgkorna – förutom ett rådjur. Livsmiljöanvändning under vinter varierade något mellan arterna där älgarna visade minst variation för olika livsmiljöer jämfört med tallskog och i relation till rådjur och kronhindar. Likaså under sommaren använde älgkorna ingen livsmiljö mer eller mindre än tallskog, medan rådjuren och kronhindarna visade en tydlig selektion för andra livsmiljöer än tallskog under vår/sommarperioden. Studier i Nordmalings området har ökat vår förståelse om hur älg, rådjur och kronhindar nyttjar ett borealt landskap på nordliga breddgrader. En viktig orsak till att försökspopulationen i Nordmaling fungerar så bra är det nära samarbetet med alla intresserade. Intresset är mycket stort, många olika användare är inne på hemsidan www.slu.se/alg-forskning.
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| 9. |
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| 10. |
- Andersson, Leif, et al.
(författare)
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”Supergen” bakom olika strategier
- 2016
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Ingår i: Vår Fågelvärld. - 0042-2649. ; , s. 22-27
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 11. |
- Bergqvist, Göran, et al.
(författare)
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Klövviltsobs i tre pilotlän
- 2016
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Ingår i: Svensk jakt. - 0039-6583. ; , s. 54-54
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 12. |
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| 13. |
- Díez-del-Molino, David, et al.
(författare)
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Population genomics reveals lack of greater white-fronted introgression into the Swedish lesser white-fronted goose
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Interspecific introgression is considered a potential threat to endangered taxa. One example where this has had a major impact on conservation policy is the lesser white-fronted goose (LWfG). After a dramatic decline in Sweden, captive breeding birds were released between 1981–1999 with the aim to reinforce the population. However, the detection of greater white-fronted goose (GWfG) mitochondrial DNA in the LWfG breeding stock led to the release program being dismantled, even though the presence of GWfG introgression in the actual wild Swedish LWfG population was never documented. To examine this, we sequenced the complete genomes of 21 LWfG birds from the Swedish, Russian and Norwegian populations, and compared these with genomes from other goose species, including the GWfG. We found no evidence of interspecific introgression into the wild Swedish LWfG population in either nuclear genomic or mitochondrial data. Moreover, Swedish LWfG birds are genetically distinct from the Russian and Norwegian populations and display comparatively low genomic diversity and high levels of inbreeding. Our findings highlight the utility of genomic approaches in providing scientific evidence that can help improve conservation management as well as policies for breeding and reinforcement programmes.
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| 14. |
- Fabri, Nannet, et al.
(författare)
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Wild ungulate species differ in their contribution to the transmission of Ixodes ricinus-borne pathogens
- 2021
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Ingår i: Parasites and Vectors. - : Springer Science and Business Media LLC. - 1756-3305. ; 14
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Tidskriftsartikel (refereegranskat)abstract
- Background Several ungulate species are feeding and propagation hosts for the tick Ixodes ricinus as well as hosts to a wide range of zoonotic pathogens. Here, we focus on Anaplasma phagocytophilum and Borrelia burgdorferi (s.l.), two important pathogens for which ungulates are amplifying and dilution hosts, respectively. Ungulate management is one of the main tools to mitigate human health risks associated with these tick-borne pathogens. Across Europe, different species of ungulates are expanding their ranges and increasing in numbers. It is currently unclear if and how the relative contribution to the life-cycle of I. ricinus and the transmission cycles of tick-borne pathogens differ among these species. In this study, we aimed to identify these relative contributions for five European ungulate species. Methods We quantified the tick load and collected ticks and spleen samples from hunted fallow deer (Dama dama, n = 131), moose (Alces alces, n = 15), red deer (Cervus elaphus, n = 61), roe deer (Capreolus capreolus, n = 30) and wild boar (Sus scrofa, n = 87) in south-central Sweden. We investigated the presence of tick-borne pathogens in ticks and spleen samples using real-time PCR. We determined if ungulate species differed in tick load (prevalence and intensity) and in infection prevalence in their tissue as well as in the ticks feeding on them. Results Wild boar hosted fewer adult female ticks than any of the deer species, indicating that deer are more important as propagation hosts. Among the deer species, moose had the lowest number of female ticks, while there was no difference among the other deer species. Given the low number of infected nymphs, the relative contribution of all ungulate species to the transmission of B. burgdorferi (s.l.) was low. Fallow deer, red deer and roe deer contributed more to the transmission of A. phagocytophilum than wild boar. Conclusions The ungulate species clearly differed in their role as a propagation host and in the transmission of B. burgdorferi and A. phagocytophilum. This study provides crucial information for ungulate management as a tool to mitigate zoonotic disease risk and argues for adapting management approaches to the local ungulate species composition and the pathogen(s) of concern. Graphic abstract
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| 15. |
- Felton, Annika, et al.
(författare)
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Forage availability, supplementary feed and ungulate density : Associations with ungulate damage in pine production forests
- 2022
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Ingår i: Forest Ecology and Management. - : Elsevier. - 0378-1127 .- 1872-7042. ; 513
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Tidskriftsartikel (refereegranskat)abstract
- Populations of large herbivores, including members of the deer family Cervidae, are expanding across and within many regions of the northern hemisphere. Because their browsing on trees can result in economic losses to forestry and strongly affect ecosystems, it is becoming increasingly important to understand how best to mitigate resultant damage. Previous research has highlighted the importance of regulating deer density and the availability of alternative forage to reduce browsing damage levels in conifer production stands. However, often only one or two proxies of forage availability have been used instead of applying a broad foodscape approach and more knowledge is needed to understand which types of alternative forage best mitigate damage. We conducted field inventories of damage that occurred during the previous fall/winter in 112 production stands in southern Sweden, while also measuring forage availability and cervid faecal pellets in the surrounding landscape (16 ha). Local landowners provided data on supplementary feeding. We found that variation in cervid (Alces alces, Capreolus capreolus, Cervus elaphus and Dama dama) browsing damage to top shoots or stems of young Scots pine trees (Pinus sylvestris, hereon pine), was better explained by the availability of alternative natural forage (using several indices and species of trees and shrubs) than by supplementary feeding. The proportion of damaged pine trees was higher in stands with a lower density of pine stems; in landscapes with a lower density of key broadleaf tree species (genera Sorbus, Salix, Populus and Quercus); and in landscapes with more open land (agricultural fields and paddocks). Damage was also higher in stands where relatively large amounts of moose faeces was found, while not related to the amount of faeces from other cervid species. The amount of supplementary feed (silage or other types such as root vegetables) did not explain variation in pine damage, but the result was possibly affected by relatively few study areas supplying sufficient data on supplementary feeding. The results from our inventory illustrate the efficacy of using naturally growing forage to mitigate browsing damage to young pine trees in managed landscapes. Creation of such forage is also recommended over supplementary feeding because of co-benefits to forest biodiversity and ecosystem services.
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| 16. |
- Felton, Annika, et al.
(författare)
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Varied diets, including broadleaved forage, are important for a large herbivore species inhabiting highly modified landscapes
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Diet quality is an important determinant of animal survival and reproduction, and can be described as the combination of different food items ingested, and their nutritional composition. For large herbivores, human landscape modifications to vegetation can limit such diet-mixing opportunities. Here we use southern Sweden's modified landscapes to assess winter diet mixtures (as an indicator of quality) and food availability as drivers of body mass (BM) variation in wild moose (Alces alces). We identify plant species found in the rumen of 323 moose harvested in Oct-Feb, and link variation in average calf BM among populations to diets and food availability. Our results show that variation in calf BM correlates with variation in diet composition, diversity, and food availability. A varied diet relatively rich in broadleaves was associated with higher calf BM than a less variable diet dominated by conifers. A diet high in shrubs and sugar/starch rich agricultural crops was associated with intermediate BM. The proportion of young production forest (0-15yrs) in the landscape, an indicator of food availability, significantly accounted for variation in calf BM. Our findings emphasize the importance of not only diet composition and forage quantity, but also variability in the diets of large free-ranging herbivores.
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| 17. |
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| 18. |
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| 19. |
- Helldin, Jan Olof, et al.
(författare)
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The impacts of wind power on terrestrial mammals : A synthesis
- 2012
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- We compiled available knowledge and experience of the impact of wind power on terrestrial mammals, both wild and domestic. The literature in the field is very limited, so we also tried to draw lessons from related fields, such as disturbance from noise, construction work, traffic, hunting and outdoor activities, and the effects of habitat change.Although the knowledge is generally sparse, the summary shows that it is possible that terrestrial mammals, especially large carnivores and ungulates including domestic reindeer, are affected by wind power development in various ways.For the larger game species as well as domestic reindeer, the influence from wind power should primarily be due to the network of access roads to the turbines. The main factor is probably the increased access for recreation, hunting and leisure traffic. It is well known that interference from such human activities can impact moose, wild deer, domestic reindeer and large carnivores, and in effect cause a habitat loss.New wind power farms are expected to be situated in more remote, upland, currently roadless areas, at least in the forested landscape. Such areas may serve as refugia for e.g. large predators or as important grazing areas for ungulates. Accordingly, wind power and associated infrastructure in these areas may have an impact on the population level of these species.By contrast, the habitat changes caused by access roads are not necessarily a problem for the larger mammal species. Open land, new edge zones and roadsides could rather benefit many wildlife species. Open land and edges create new browsing areas; roads can facilitate animal movement in the landscape or help animals escaping parasitic insects.The effects of power lines on reindeer tend to differ depending on the geographic scale studied; on a regional scale, an avoidance of large areas around power lines may be observed, while no effects have been shown for reindeer studied near power lines.A few studies available on wild deer, reindeer and large carnivores during construction work suggest that these animals may temporarily avoid wind farms during this period. However, the data is not conclusive.Noise emissions from wind turbines can theoretically disturb animal communication, and also visual stimuli (including reflections, shadows and lighting) may annoy or stress both wildlife and livestock. However, the few studies available suggest the lack of such effects, or a swift habituation to the disturbance, and therefore a limited impact.Animals may also get accustomed to the other disturbances from wind power. For example, both domestic and wild reindeer appear to remain in areas despite human presence, at least when no alternative areas are available. The ability to habituate varies with species, sex, age, individual, time of year, type of disturbance, and how frequent and predictable disturbances are, so overall, habituation cannot be presupposed.There may be differences in the response to disturbance, depending on landscape and current land use. In already disturbed areas, such as most agricultural landscapes, wind power may not affect the occurring species to the same extent as it would in more sparsely populated forest and mountain areas.The effects may also depand on the size of the wind farm. At the construction of large wind farms, even small and localised effects may sum up to significant impact, with consequences at the population level.Our summary highlights the large knowledge gaps in the field and indicates the need for research as well as for efficient environmental monitoring. Of particular need is to study the effects of noise and visual impacts from the turbines. Also studies are needed on the localisation of new wind power in relation to areas of particular value for ungulates and large predators. It is important that the potential cumulative impacts of wind power are considered, as these may lead to consequences at the population level and thus be most relevant from a conservation perspective.To address the large knowledge gaps, it is crucial that monitoring programs for new wind power are set up to create new, generalisable knowledge. We describe some principles that should be followed to achieve this. It is also important that monitoring programs are coordinated nationally and that the data are analysed on a comprehensive level.
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| 20. |
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| 21. |
- Hill, Jason, et al.
(författare)
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Low Mutation Load in a Supergene Underpinning Alternative Male Mating Strategies in Ruff (Calidris pugnax)
- 2023
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Ingår i: Molecular biology and evolution. - : Oxford University Press. - 0737-4038 .- 1537-1719. ; 40:12
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Tidskriftsartikel (refereegranskat)abstract
- A paradox in evolutionary biology is how supergenes can maintain high fitness despite reduced effective population size, the suppression of recombination, and the expected accumulation of mutational load. The ruff supergene involves 2 rare inversion haplotypes (satellite and faeder). These are recessive lethals but with dominant effects on male mating strategies, plumage, and body size. Sequence divergence to the wild-type (independent) haplotype indicates that the inversion could be as old as 4 million years. Here, we have constructed a highly contiguous genome assembly of the inversion region for both the independent and satellite haplotypes. Based on the new data, we estimate that the recombination event(s) creating the satellite haplotype occurred only about 70,000 yr ago. Contrary to expectations for supergenes, we find no substantial expansion of repeats and only a modest mutation load on the satellite and faeder haplotypes despite high sequence divergence to the non-inverted haplotype (1.46%). The essential centromere protein N (CENPN) gene is disrupted by the inversion and is as well conserved on the inversion haplotypes as on the noninversion haplotype. These results suggest that the inversion may be much younger than previously thought. The low mutation load, despite recessive lethality, may be explained by the introgression of the inversion from a now extinct lineage.
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| 22. |
- Holmes, Sheila, et al.
(författare)
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Declining recruitment and mass of Swedish moose calves linked to hot, dry springs and snowy winters
- 2021
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Ingår i: Global Ecology and Conservation. - : Elsevier BV. - 2351-9894. ; 27
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Tidskriftsartikel (refereegranskat)abstract
- As global temperatures continue to rise, increases in the frequency and intensity of climatic extremes will likely outpace average temperature increases, and may have outsized impacts on biological populations. Moose (Alces alces) are adapted to cold weather and populations are declining at the southern edge of the species' range. Moose therefore make a suitable case study to examine the relationship between population performance and both climatic averages and the frequency of rare, intense climatic events. More than twenty years of slaughter weights and moose observations collected by hunting teams across all of Sweden show that early calf recruitment has declined throughout Sweden and calf mass has also declined, particularly in central and southern Sweden. Spring weather affected mean calf mass, which declined with higher average temperatures, more frequent very hot days (days in the 95th percentile for maximum temperature) and less precipitation during this season, though in the case of hot days only when high temperatures coincided with low rainfall. This supports previous observations of moose sensitivity to both direct heat stress and the negative impacts of hot, dry spring weather on forage quality. Recruitment was similarly impacted, and the interaction between the previous year's temperature and precipitation supports a lagged effect of weather on recruitment, via female condition. Finally, cold winter temperatures and deeper snow were associated with reduced calf mass during the following autumn, while deeper snow was additionally linked to fewer calves per female. Our results suggest that similar patterns may exist for averages and the frequency of extreme values, but it is important to examine both in order to improve biological relevance. The significant and ongoing declines in calf mass in southern populations and calf recruitment throughout Sweden should serve as an early warning that Eurasian moose may suffer from climate change in similar ways to North American moose. We discuss conservation management strategies, both in terms of harvest as well as landscape management, that may help mitigate the observed patterns. (C) 2021 The Author(s). Published by Elsevier B.V.
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| 23. |
- Holmes, Sheila, et al.
(författare)
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Increased summer temperature is associated with reduced calf mass of a circumpolar large mammal through direct thermoregulatory and indirect, food quality, pathways
- 2023
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Ingår i: Oecologia. - 0029-8549 .- 1432-1939.
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Tidskriftsartikel (refereegranskat)abstract
- Climate change represents a growing ecological challenge. The (sub) arctic and boreal regions of the world experience the most rapid warming, presenting an excellent model system for studying how climate change afects mammals. Moose (Alces alces) are a particularly relevant model species with their circumpolar range. Population declines across the southern edge of this range are linked to rising temperatures. Using a long-term dataset (1988–1997, 2017–2019), we examine the relative strength of direct (thermoregulatory costs) and indirect (food quality) pathways linking temperature, precipitation, and the quality of two important food items (birch and freweed) to variation in moose calf mass in northern Sweden. The direct efects of temperature consistently showed stronger relationships to moose calf mass than did the indirect efects. The proportion of growing season days where the temperature exceeded a 20 °C threshold showed stronger direct negative relationships to moose calf mass than did mean temperature values. Finally, while annual forb (freweed) quality was more strongly infuenced by temperature and precipitation than were perennial (birch) leaves, this did not translate into a stronger relationship to moose calf weight. The only indirect path with supporting evidence suggested that mean growing season temperatures were positively associated with neutral detergent fber, which was, in turn, negatively associated with calf mass. While indirect impacts of climate change deserve further investigation, it is important to recognize the large direct impacts of temperature on cold-adapted species.
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| 24. |
- Johansson, Björn, et al.
(författare)
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Cost of pheromone production in a lekking Drosophila
- 2005
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Ingår i: Animal Behaviour. - : Elsevier BV. - 0003-3472 .- 1095-8282. ; 69:4, s. 851-858
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Tidskriftsartikel (refereegranskat)abstract
- ‘Sex pheromones’ are most commonly seen as mate attraction signals. However, there is growing evidence that chemical signals may also advertise mate quality. Theory predicts that for mate quality signals to be reliable they should be costly, a mechanism that is likely to drive condition-dependent expression of the signal in question. We investigated the relation between pheromone production and life span in Drosophila grimshawi, a lekking fruit fly where males deposit pheromones on the lekking arena. We manipulated pheromone production by subjecting males to another male, a female or no companion twice a week for the duration of their adult lives. We found that long-lived males deposited pheromones for a greater proportion of their lives across treatments. Males that met other males, rather than females or no flies, also deposited pheromones for a greater proportion of their lives. However, this greater investment seemed to be costly since these males also had shorter life spans, presumably as a result of increased pheromone production. Thus, our results support the notion that pheromone production may act as an honest signal of quality. Furthermore, we show that the pheromone has multiple functions and that male D. grimshawi appear to adjust their investment in pheromone production in relation to their social environment.
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| 25. |
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| 26. |
- Johansson, Björn G., 1968-
(författare)
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Chemical Communication and Mate Choice : Investigations into the Meaning of a Fruit Fly Pheromone
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Chemical signals are the most widely used form of sexual communication throughout the living world. However, there is in general little knowledge about what these signals actually communicate. The role of chemical signals, i.e. pheromones, in sexual behaviour has traditionally been seen as restricted to mate attraction and species recognition. This thesis reviews the evidence for pheromones as indicators of mate quality, and then investigates three important factors for mate quality signals – individual variation, heritability and cost – by using the male pheromone of the lekking fruit fly Drosophila grimshawi as a model.The experiments presented indicate that the pheromone of D. grimshawi has multiple functions, and that these functions vary with social context. Thus, with regard to females, the pheromone seems to act mainly as a species/mate recognition signal, since females show little preference for the amount of pheromone deposited by a male. Moreover, males invest less in pheromone production when subjected to females as compared to when subjected to rival males. However, the pheromone seems to be costly in production since males that invest much in pheromone deposition has a shorter lifespan. This suggests a function for the pheromone in male-male interactions. Males can distinguish their own pheromone depositions from those of a strange male, and also discriminate between pheromone depositions from one and two strange males. This might give them the ability to assess the size of a lek and the competitive capacities of rivals, information that should be useful when optimizing sexual behaviour.In conclusion, the pheromone seems to act as an honest mate/competitor quality signal in some social contexts, and as a non-costly species/mate recognition signal in other. In addition, I show for the first time that a chemical signal has differential fitness costs, and that an insect is able to distinguish between individual odour signatures.
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| 27. |
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| 28. |
- Lamichhaney, Sangeet, 1984-, et al.
(författare)
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Structural genomic changes underlie alternative reproductive strategies in the ruff (Philomachus pugnax)
- 2016
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Ingår i: Nature Genetics. - : Springer Nature. - 1061-4036 .- 1546-1718. ; 48:1, s. 84-88
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Tidskriftsartikel (refereegranskat)abstract
- The ruff is a Palearctic wader with a spectacular lekking behavior where highly ornamented males compete for females1,2,3,4. This bird has one of the most remarkable mating systems in the animal kingdom, comprising three different male morphs (independents, satellites and faeders) that differ in behavior, plumage color and body size. Remarkably, the satellite and faeder morphs are controlled by dominant alleles5,6. Here we have used whole-genome sequencing and resolved the enigma of how such complex phenotypic differences can have a simple genetic basis. The Satellite and Faeder alleles are both associated with a 4.5-Mb inversion that occurred about 3.8 million years ago. We propose an evolutionary scenario where the Satellite chromosome arose by a rare recombination event about 500,000 years ago. The ruff mating system is the result of an evolutionary process in which multiple genetic changes contributing to phenotypic differences between morphs have accumulated within the inverted region.
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| 29. |
- Neumann, Wiebke, et al.
(författare)
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Hunting as land use: Understanding the spatial associations among hunting, agriculture, and forestry
- 2022
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Ingår i: Ecology and Society. - 1708-3087. ; 27
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Tidskriftsartikel (refereegranskat)abstract
- Hunting is a widespread but often overlooked land-use activity, providing major benefits to society. Hunting takes place in most landscapes, yet it remains unclear which types of landscapes foster or dampen hunting-related services, and how hunting relates to other land uses. A better understanding of these relationships is key for sustainable land-use planning that integrates wildlife management. This is particularly urgent for Europe, where wildlife populations are increasing. Focusing on Sweden, we explored the spatial associations among hunting, agriculture, and forestry to identify archetypical combinations of these land uses. Specifically, we combined indicators on the extent and intensity of agriculture and forestry, with data on hunting bags for 63 game species using self-organizing maps, a non-parametric clustering approach. We identified 15 typical bundles of co-occurring land uses at the municipality level across Sweden. The harvest of forest grouse, bears, and moose co-occurred with forestry in northern Sweden, whereas the harvest of small game, different deer species, and wild boar co-occurred with agriculture across southern Sweden, reflecting species’ biology, environmental factors, and management. Our findings also highlight the strength of associations among hunting and other land uses. Importantly, we identified large areas in central Sweden where harvest of game was below average, possibly indicating that intensity of hunting is out of balance with that of agriculture or forestry, potentially fostering conflict between wildlife and land use. Collectively, our results suggest that (1) hunting should be considered a major land use that, in Sweden, is more widespread than agriculture and forestry; (2) land-use planning must therefore integrate wildlife management; and (3) such an integration should occur in a regionalized manner that considers social-ecological context. Our approach identifies a first spatial template within which such context-specific land-use planning, aiming at aligning wildlife and diverse land uses, can take place.
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| 30. |
- Neumann, Wiebke, et al.
(författare)
-
Strength of correlation between wildlife collision data and hunting bags varies among ungulate species and with management scale
- 2020
-
Ingår i: European Journal of Wildlife Research. - : Springer Science and Business Media LLC. - 1612-4642 .- 1439-0574. ; 66
-
Tidskriftsartikel (refereegranskat)abstract
- Most European ungulate species are increasing in numbers and expanding their range. For the management and monitoring of these species, 64% of European countries rely on indirect proxies of abundance (e.g., hunting bag statistics). With increasing ungulate numbers, data on ungulate-vehicle collisions (UVC) may provide an important and inexpensive, complementary data source. Currently, it is unclear how bag statistics compare with UVC. A direct comparison of these two indices is important because both are used in ungulate management. We evaluated the relationship between UVC and ungulate hunting bags across bioclimatic, regional, and local scales, using five time lags (t(-3)to t(+1)) for the five most common wild ungulate species in Sweden. For all species, hunting bags and UVC correlated positively, but correlation strength and time lags varied across scales and among species. The two indices correlated most strongly at the local management scale. Correlation between both indices was strong for the smaller deer species and wild boar, in particular, but much weaker for moose where we found the best fit using a 2-year time lag. For the other species, indices from the same year correlated best. We argue that the reason for moose data behaving differently is that, in Sweden, moose are formally managed using a 3-year time plan, while the other species are not. Accordingly, moose hunting bags are influenced more strongly by density-independent processes than bags of the other species. Consequently, the mismatch between the two indices may generate conflicting conclusions for management depending on the method applied.
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| 31. |
- Pfeffer, Sabine, et al.
(författare)
-
Pictures or pellets? Comparing camera trapping and dung counts as methods for estimating population densities of ungulates
- 2018
-
Ingår i: Remote sensing in ecology and conservation. - : Wiley. - 2056-3485. ; 4, s. 173-183
-
Tidskriftsartikel (refereegranskat)abstract
- Across the northern hemisphere, land use changes and, possibly, warmer win- ters are leading to more abundant and diverse ungulate communities causing increased socioeconomic and ecological consequences. Reliable population esti- mates are crucial for sustainable management, but it is currently unclear which monitoring method is most suitable to track changes in multi-species assem- blages. We compared dung counts and camera trapping as two non-invasive census methods to estimate population densities of moose Alces alces and roe deer Capreolus capreolus in Northern Sweden. For camera trapping, we tested the random encounter model (REM) which can estimate densities without the need to recognize individual animals. We evaluated different simplification options of the REM in terms of estimates of detection distance and angle (raw data vs. modelled) and of daily movement rate (camera trap based vs. telemetry based). In comparison to density estimates from camera traps, we found that, dung counts appeared to underestimate population density for roe deer, but not for moose. Estimates of detection distance and angle from modelled versus raw camera data resulted in nearly identical outcomes. The telemetry-derived daily movement rate for moose and roe deer resulted in much higher density estimates than the camera trap-derived estimates. We suggest that camera trap- ping may be a robust complement to dung counts when monitoring ungulate communities, particularly when similarities between dung pellets from sympatric deer species make unambiguous assignment difficult. Moreover, we show that a simplified use of the REM method holds great potential for large-scale citizen science-based programmes (e.g. involving hunters) that can track the rapidly changing European wildlife landscape. We suggest to include camera trapping in management programmes, where the analysis can be verified via web-based applications.
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| 32. |
- Pfeffer, Sabine, et al.
(författare)
-
Predictors of browsing damage on commercial forests – A study linking nationwide management data
- 2021
-
Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 479
-
Tidskriftsartikel (refereegranskat)abstract
- Population sizes and species distributions of wild ungulates in Europe have increased during the past decades, and continue to do so. As a result, browsing pressure in forests is increasing and concerns about the effects of increasingly common multi-species deer communities on forestry are rising. However, we currently lack an understanding of how the composition of deer communities affects browsing damage, particularly with respect to the role of species with different dietary requirements. Further, the relative importance of predictors of browsing damage in systems with multiple browsers remains elusive. Here, we used data from Swedish management, which is monitoring ungulates and their damage to forests, to test how deer densities, forage availability, and winter severity predict browsing damage on commercially important Scots pine (Pinus sylvestris) at national and regional scales. Moose (Alces alces) is the main browser of Scots pine, but competes with other deer over more preferred forage. During winter, a higher index of moose density was associated with higher browsing damage in northern Sweden, where there is low competition from other deer. In southern Sweden, competition from other deer is higher and a higher density index of roe deer (Capreolus capreolus) was associated with higher winter damage. However, there was no relationship between moose density and damage. We suggest that moose are forced to browse more pine due to interspecific competition over alternative forage resources in the south, yielding stronger relationships between densities of competing deer species and damage than between moose density and damage. Pine density, a proxy for forage availability, was an equally or more important determinant for browsing damage as deer density indices in most regions. Increasing pine density was associated with reduced browsing damage caused in winter in all regions and reduced damage caused in summer in central Sweden. Increased winter severity, as an index of snow depth, predicted increased winter damage in the northern region only. To reduce winter damage, our results suggest that management should consider deer densities and forage availability simultaneously, while adopting a multi-species approach. Results varied among regions, with densities of other deer being more relevant in the south and winter severity more relevant in the north. Management data did not predict summer damage well. Since national models did not capture regional variations, we conclude that management decisions and actions need to be tailored to the regional or local scale.
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| 33. |
- Pfeffer, Sabine, et al.
(författare)
-
Summer and winter browsing affect conifer growth differently: An experimental study in a multi-species ungulate community
- 2021
-
Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 494
-
Tidskriftsartikel (refereegranskat)abstract
- Ungulate browsing has been studied for several decades in the northern hemisphere. However, studies have mainly focused on just one or two ungulate species, while rarely contrasting the relative effects of summer and winter browsing. This limits our understanding of the dynamics and effects of browsing in landscapes where ungulate species diversity is increasing. We conducted a seasonal exclosure experiment on former clear-cuts in a multi-species ungulate system in Sweden, to investigate the relative impacts of summer and winter browsing on the conifers Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) at the tree species level. We tested for differences in individual conifer growth and demographic responses between Summer browsing, Winter browsing, No browsing, and Control treatment plots over a 4.5 year experimental period. We defined the demographic response as the distribution of conifers among different height classes. Individual growth rates and demographic responses of both conifer species were similar in the plots with No browsing (year-round exclosures) as in the Control plots with year-round browsing. Plots subject to Summer and Winter browsing differed in terms of their demographic response relative to plots with No browsing and Control plots; more stems reached taller height classes in the Summer and Winter browsing plots with slight differences between the conifer species. We discuss the different responses of Scots pine and Norway spruce considering their differences in palatability and their ability to tolerate plant-plant competition in a multi-species ungulate system, in light of potential associational effects. If fencing is intended to be used as a management practice to mitigate the impacts of deer browsing on conifer growth, our results suggest that a total exclusion of deer does not necessarily enhance conifer growth during the first years of regeneration.
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| 34. |
- Ramirez, J. Ignacio, et al.
(författare)
-
Applied ecology of fear : a meta-analysis on the potential of facilitating human-wildlife coexistence through nonlethal tools
- 2024
-
Ingår i: Ecological Solutions and Evidence. - : John Wiley & Sons. - 2688-8319. ; 5:2
-
Tidskriftsartikel (refereegranskat)abstract
- 1. The term “applied ecology of fear” was recently introduced to describe the growing research field that applies the theory of the ecology of fear to manage wildlife behaviour. The management goal is to drive targeted species spatially and temporally away from areas of human interest by inducing cues from real or simulated predators to reduce human-wildlife conflict.2. We aimed to quantify, through a meta-analysis, if prey anti-predator response would vary among field trials versus pen-based studies, predator cue types, predator hunting style and prey feeding type, and be stronger in response to larger predators relative to the prey's size. We also explored what studies found in terms of wildlife habituation to cues.3. We used species belonging to the Cervidae family as a case study since deer are among the group of species with the highest degree of human-wildlife conflict. We retrieved 114 studies from online databases and collected information from 39 of those studies that fitted our research scope.4. We found that acoustic cues more frequently led to an anti-predator response in deer than olfactory or visual cues. Neither predator hunting strategy nor deer feeding strategy or type of study (free-ranging or pen-based animals) influenced the extent to which deer responded to cues. Deer more frequently responded to cues that belonged to a larger predator relative to their size. Habituation was reported in less than one-third of the studies, with a study period ranging from 1 to 90 days, and occurred as soon as 7 days after the start of the study on average.5. Our meta-analysis suggested that acoustic cues hold most potential as a tool to manage deer behaviour. These findings support the development of applied ecology of fear tools that introduce predator cues to reduce human-wildlife conflicts. Major knowledge gaps remain that limit the effective use of such tools in wildlife management and future research should focus on improving our understanding of habituation to cues, on comparing the effectiveness of different types of cues, on simultaneously using a combination of cue types, and on testing cues at spatial–temporal scales of actual land-uses.
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| 35. |
- Roberge, Jean-Michel, et al.
(författare)
-
Socio-ecological implications of modifying rotation lengths in forestry
- 2016
-
Ingår i: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 45, s. 109-123
-
Tidskriftsartikel (refereegranskat)abstract
- The rotation length is a key component of even-aged forest management systems. Using Fennoscandian forestry as a case, we review the socioecological implications of modifying rotation lengths relative to current practice by evaluating effects on a range of ecosystem services and on biodiversity conservation. The effects of shortening rotations on provisioning services are expected to be mostly negative to neutral (e.g. production of wood, bilberries, reindeer forage), while those of extending rotations would be more varied. Shortening rotations may help limit damage by some of today's major damaging agents (e.g. root rot, cambium-feeding insects), but may also increase other damage types (e.g. regeneration pests) and impede climate mitigation. Supporting (water, soil nutrients) and cultural (aesthetics, cultural heritage) ecosystem services would generally be affected negatively by shortened rotations and positively by extended rotations, as would most biodiversity indicators. Several effect modifiers, such as changes to thinning regimes, could alter these patterns.
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| 36. |
- Spitzer, Robert, et al.
(författare)
-
Doubting dung: eDNA reveals high rates of misidentification in diverse European ungulate communities
- 2019
-
Ingår i: European Journal of Wildlife Research. - : Springer Science and Business Media LLC. - 1612-4642 .- 1439-0574. ; 65
-
Tidskriftsartikel (refereegranskat)abstract
- Pellet counts are widely used to monitor ungulates but rely on the assumption that pellets of different species are correctly identified in the field. Recent studies question this assumption using DNA barcoding techniques to check field identification rates. For Europe, which is undergoing a rapid shift towards more diverse ungulate assemblages, such an assessment is still missing. Using DNA barcoding on 3889 fecal samples from nine ungulate species in four European countries, we found average field misidentification rates varied from 0.6% for horse (Equus ferus) to 41.1% for roe deer (Capreolus capreolus). Most identification errors occurred between similar-sized species from the same taxonomic family. For a subset of samples from Sweden, we looked at the effect of dung morphometry, observer experience, and season on species identification success. Dung morphometry clearly distinguished moose (Alces alces) but not red (Cervus elaphus), roe, and fallow deer (Dama dama). Experienced observers performed better than novices for red and fallow deer although still making significant identification errors (26% and 17% incorrectly identified). Identification success was higher during spring and winter. We question pellet counts as an accurate monitoring tool where similar-sized species coexist and monitoring relates to the whole community. For this increasingly common situation across Europe, DNA testing or camera traps may be a better alternative. Pellet counts remain useful where only few species with clearly different dung morphology coexist (e.g., moose and roe deer) or when focused on species with distinctive dung morphology (e.g., moose).
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| 37. |
- Spitzer, Robert, et al.
(författare)
-
Fifty years of European ungulate dietary studies: a synthesis
- 2020
-
Ingår i: Oikos. - : Wiley. - 0030-1299 .- 1600-0706. ; 129, s. 1668-1680
-
Tidskriftsartikel (refereegranskat)abstract
- Over recent decades, ungulate populations across Europe have undergone a rapid recovery. While this constitutes a conservation success, there is increasing concern about their impacts on shared resources with humans. Understanding ungulate food choices is crucial for predicting such impacts. Numerous studies have focused on single species or communities at narrow spatial scales. Here, we used 265 published diets from 87 European studies to investigate patterns of resource use by four common deer species (mooseAlces alces, red deerCervus elaphus, roe deerCapreolus capreolusand fallow deerDama dama), and wild boarSus scrofaat the continental scale. On average, deer diets separated mostly along a gradient from grass to browse. Fallow deer diets contained the most and moose diets the least amount of grass, but we also found large intraspecific variation among all deer species. Diets of roe deer, a presumed browser, frequently contained >= 25% grass. Wild boar diet contained grass in amounts similar to red deer but otherwise differed strongly from deer diets. All five ungulate species shifted to eating higher proportions of woody browse during winter. Habitat influenced variation in intraspecific diets, but the proportions of key forage types related to feeding type (i.e. grass for intermediate feeders red and fallow deer, and shrubs for the browsers moose and roe deer) remained fairly consisted across habitat types. In northern and central Europe, diet similarity between roe deer and red deer was highest during winter and spring and lowest during summer and autumn but remained constant across the seasons in southern Europe. We foresee that, as interspecific interactions driven by land-use and climatic changes increase across Europe, further monitoring and testing will be needed to understand the dynamics of dietary niche partitioning among ungulates.
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| 38. |
- Spitzer, Robert, et al.
(författare)
-
Macro-nutritional balancing in a circumpolar boreal ruminant under winter conditions
- 2023
-
Ingår i: Functional Ecology. - : Wiley. - 0269-8463 .- 1365-2435. ; 37, s. 1256-1268
-
Tidskriftsartikel (refereegranskat)abstract
- 1. Differences in botanical diet compositions among a large number of moose faecal samples collected during winter correlated with the nutritional differences identified in the same samples (Mantel r = 0.89, p = 0.001), but the nutritional differences were significantly smaller (p < 0.001).2. Nutritional geometry revealed that moose mixed Scots pine Pinus sylvestris and Vaccinium spp. as nutritionally complementary foods to reach a nutritional target resembling Salix spp. twigs, and selected for Salix spp. browse (Jacob's D > 0).3. Available protein (AP) and total non-structural carbohydrates (TNC) were significantly correlated in observed diets but not in hypothetical diets based on food availability.4. The level of Acetoacetate in moose serum (i.e. "starvation') was weakly negatively associated with digestibility of diets (p = 0.08) and unrelated to increasing AP:TNC and AP:NDF ratios in diets (p > 0.1).5. Our study is the first to demonstrate complementary feeding in free-ranging moose to attain a nutritional target that has previously been suggested in a feeding trial with captive moose. Our results add support to the hypothesis of nutritional balancing as a driver in the nutritional strategy of moose with implications for both the management of moose and food resources.
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| 39. |
- Spitzer, Robert, et al.
(författare)
-
Small shrubs with large importance? Smaller deer may increase the moose-forestry conflict through feeding competition over Vaccinium shrubs in the field layer
- 2021
-
Ingår i: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 480
-
Tidskriftsartikel (refereegranskat)abstract
- The moose (Alces alces) is a dominant large mammalian herbivore in the world's boreal zones. Moose exert significant browsing impacts on forest vegetation and are therefore often at the centre of wildlife-forestry conflicts. Consequently, understanding the drivers of their foraging behaviour is crucial for mitigating such conflicts. Management of moose in large parts of its range currently largely ignores the fact that moose foraging is influenced by increasing populations of sympatric deer species. In such multispecies systems, resource partitioning may be driven by foraging height and bite size. Feeding competition with smaller species might replace larger species from the field layer and drive them towards higher foraging strata offering larger bites. This bite size hypothesis has been well documented for African ungulate communities. Based on a large diet DNA metabarcoding dataset we suggest that feeding competition from three smaller deer species (red deer Cervus elaphus, fallow deer Dama dama, and roe deer Capreolus capreolus) over Vaccinium shrubs in the forest field layer might drive moose towards increasing consumption of Scots pine (Pinus sylvestris) in Sweden. We found that in areas of high deer density, moose diets consistently contained less Vaccinium and higher proportions of pine over three spring periods. Utilization of these food items by the smaller deer species was either unaffected by deer density or, for Vaccinium showed the opposite pattern to moose, i.e., increases of proportions in the diet of roe and red deer with increasing deer density. Availability of pine and Vaccinium, measured as proportion of available bites, did not explain the observed patterns. Our results suggest that managing key food items like Vaccinium and the populations of smaller deer may play an important role in controlling browsing impacts of moose on pine.
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| 40. |
- Thuman, Katherine
(författare)
-
Female Reproductive Strategies in the Ruff (Philomachus pugnax)
- 2003
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Traditionally, females have been considered to be strictly monogamous. Today, we know that females in the majority of species actively seek out and mate with several males. Trying to understand female preferences, including what benefits mate choice entails, has been the focus of intense research during the last decades. Females can gain both direct (e.g. access to better territories or paternal care) and indirect (i.e. genetic) benefits. The aim of this thesis is to further our understanding of the female reproductive strategies in the ruff, Philomachus pugnax (Aves, Scolopacidae). The ruff is a lekking wader, where males gather on leks to display to females that come there to mate. Males do not provide any paternal care to the offspring. Lekking systems are ideal for studying indirect benefits of female choice, as females do not gain any direct benefits from males.Females mated with several males and 50% of the broods were fathered by at least two males. The level of genetic similarity between two parents has previously been shown to be an important source of variation in offspring fitness. Males that were less closely related to the female fathered more offspring in broods with multiple paternity, such that females that mated multiply gained in terms of receiving more outbred offspring. There did not, however, appear to be an overall female preference for less closely related males. There are two genetically determined male reproductive strategies in the ruff, that differ in behaviour and morphology. There was no evidence for females taking male strategy into account when choosing a partner.Female post-fertilisation strategies may also influence fitness, e.g. through differential investment in eggs, gender of the offspring and choice of breeding habitat. Females allocated sex in a non-random manner dependent upon body condition, such that females in good condition had more daughters.Females were found to nest in higher than average vegetation and in areas with higher than average abundance of insects, factors likely to influence predation rates on both eggs and young, as well as foraging opportunities for the precocial young. Further, females were faithful to their previous breeding site and usually nested within meters of their previous nest. Hatching success did not, however, affect a female’s decision to return or not.
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| 41. |
- Wallgren, Märtha, et al.
(författare)
-
Airborne laser scanning reveals uniform responses of forest structure to moose (Alces alces) across the boreal forest biome
- 2023
-
Ingår i: Journal of Ecology. - : Wiley. - 0022-0477 .- 1365-2745.
-
Tidskriftsartikel (refereegranskat)abstract
- The moose Alces alces is the largest herbivore in the boreal forest biome, where it can have dramatic impacts on ecosystem structure and dynamics. Despite the importance of the boreal forest biome in global carbon cycling, the impacts of moose have only been studied in disparate regional exclosure experiments, leading to calls for common analyses across a biome-wide network of moose exclosures.In this study, we use airborne laser scanning (ALS) to analyse forest canopy responses to moose across 100 paired exclosure-control experimental plots distributed across the boreal biome, including sites in the United States (Isle Royale), Canada (Quebec, Newfoundland), Norway, Sweden and Finland.We test the hypotheses that canopy height, vertical complexity and above-ground biomass (AGB) are all reduced by moose and that the impacts vary with moose density, productivity, temperature and pulse disturbances such as logging and insect outbreaks.We find a surprising convergence in forest canopy response to moose. Moose had negative impacts on canopy height, complexity and AGB as expected. The responses of canopy complexity and AGB were consistent across regions and did not vary along environmental gradients. The difference in canopy height between exclosures and open plots was on average 6 cm per year since the start of exclosure treatment (+/- 2.1 SD). This rate increased with temperature, but only when moose density was high.The difference in AGB between moose exclosures and open plots was 0.306 Mg ha(-1) year(-1) (+/- 0.079). In browsed plots, stand AGB was 32% of that in the exclosures, a difference of 2.09 Mg ha(-1). The uniform response allows scaling of the estimate to a biome-wide impact of moose of the loss of 448 (+/- 115) Tg per year, or 224 Tg of carbon.Synthesis: Analysis of ALS data from distributed exclosure experiments identified a largely uniform response of forest canopies to moose across regions, facilitating scaling of moose impacts across the whole biome. This is an important step towards incorporating the effect of the largest boreal herbivore on the carbon cycling of one of the world's largest terrestrial biomes.
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| 42. |
- Widemo, Fredrik
(författare)
-
A review of circumpolar moose populations with emphasis on Eurasian moose distributions and densities
- 2020
-
Ingår i: Alces : A Journal Devoted to the Biology and Management of Moose. - 0835-5851. ; 56, s. 63-78
-
Forskningsöversikt (refereegranskat)abstract
- Moose (Alces alces) may be among one of the most susceptible big game species to climate change. Development of long-term circumpolar databases of this species’ densities and distributions, combined with biological, ecological, and management-related metrics, can help guide research and future international management strategies. We emulated methodology previously used to summarize North American moose population and harvest densities for Eurasian countries with free-ranging moose populations. From these data, we created a GIS layer that summarized the circumpolar distribution and density of moose. The following summary analysis of these data indicates that moose have both expanded and contracted along their southern range boundary in recent decades – with losses along the southern range in eastern Asia, particularly China, Mongolia, and Kazakhstan. In contrast, we documented distributional gains along the western and southwestern range in Europe (Poland, Germany, Czech Republic, Slovakia). In total, 21 countries have free-ranging moose populations; 8 with sustainable populations and hunting seasons, 5 with sustainable populations but no hunting season, and 8 with vagrant individuals occasionally sighted. A region of high-density moose populations spans from the Scandinavian and Baltic countries into the Russian oblasts of Perm and Sverdlovsk. Distributions ca. 2010 indicated that moose occupied an area of about 16,712,600 km2 in Eurasia. Primary range (management units with ≥0.11 moose per km2) composed only 18% of the occupied range while supporting more than 66% of the estimated 1.2 million moose in Eurasia. Additionally, 47% (149,860) of the moose harvested were taken on 10% (1,722,660 km2) of the range. The 2010 circumpolar moose population was estimated to be more than 2.2 million and occupied a range of 26,205,000 km2. Time-series analyses can offer a simple and cost-effective approach to monitor the status of moose populations across large geographical regions and might be particularly insightful given the current and predicted future influences of climate change on moose. Other analyses might address population dynamics, habitat, environmental constraints, and harvest management, among other issues. We encourage jurisdictions to cooperate strategically in implementing and coordinating GIS analyses to monitor, assess, and manage moose populations around the world. We believe these maps can serve as a useful tool for educating the public and policy makers about the importance of habitat and land use practices with respect to maintaining sustainable populations of moose and other species that are dependent upon boreal, temperate broadleaf, and mixed forests.
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| 43. |
- Widemo, Fredrik
(författare)
-
Detection of lead nanoparticles in game meat by single particle ICP-MS following use of lead-containing bullets
- 2017
-
Ingår i: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 409, s. 1877-1885
-
Tidskriftsartikel (refereegranskat)abstract
- This study investigated whether game meat may contain nanoparticles of lead from ammunition. Lead nanoparticles in the range 40 to 750 nm were detected by ICP-MS in single particle mode in game shot with lead-containing bullets. The median diameter of the detected nanoparticles was around 60 nm. The particle mass concentration ranged from 290 to 340 ng/g meat and the particle number concentrations from 27 to 50 million particles/g meat. The size limit of detection strongly depended on the level of dissolved lead and was in the range of 40 to 80 nm. In game meat sampled more than 10 cm away from the wound channel, no lead particles with a diameter larger than 40 nm were detected. In addition to dissolved lead in meat that originated from particulates, the presence of lead nano particles in game meat represents a hitherto unattended source of lead with a largely unknown toxicological impact to humans.
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| 44. |
|
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| 45. |
- Widemo, Fredrik
(författare)
-
Genetic variation in nuclear and mitochondrial markers supports a large sex difference in lifetime reproductive skew in a lekking species
- 2014
-
Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 4, s. 3626-3632
-
Tidskriftsartikel (refereegranskat)abstract
- Sex differences in skews of vertebrate lifetime reproductive success are difficult to measure directly. Evolutionary histories of differential skew should be detectable in the genome. For example, male-biased skew should reduce variation in the biparentally inherited genome relative to the maternally inherited genome. We tested this approach in lek-breeding ruff (Class Aves, Philomachus pugnax) by comparing genetic variation of nuclear microsatellites ((n); biparental) versus mitochondrial D-loop sequences ((m); maternal), and conversion to comparable nuclear (N-e) and female (N-ef) effective population size using published ranges of mutation rates for each marker (). We provide a Bayesian method to calculate N-e ((n)=4N(en)) and N-ef ((m)=2N(efm)) using 95% credible intervals (CI) of (n) and (m) as informative priors, and accounting for uncertainty in . In 96 male ruffs from one population, N-e was 97% (79-100%) lower than expected under random mating in an ideal population, where N-e:N-ef=2. This substantially lower autosomal variation represents the first genomic support of strong male reproductive skew in a lekking species.
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| 46. |
- Widemo, Fredrik, et al.
(författare)
-
Jägare jagar - som lodjur
- 2010
-
Ingår i: Upsala nya tidning. - 1104-0173. ; , s. 5-5
-
Tidskriftsartikel (populärvet., debatt m.m.)
|
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| 47. |
- Widemo, Fredrik
(författare)
-
Kronobs och klövviltsobs
- 2017
-
Ingår i: Svensk jakt. - 0039-6583. ; 155, s. 64-65
-
Tidskriftsartikel (populärvet., debatt m.m.)
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| 48. |
|
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| 49. |
- Widemo, Fredrik
(författare)
-
Mera tall minskar älgskadorna
- 2016
-
Ingår i: Svensk jakt. - 0039-6583. ; , s. 44-45
-
Tidskriftsartikel (populärvet., debatt m.m.)
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| 50. |
- Widemo, Fredrik, et al.
(författare)
-
Reproduktionsperioder och andra störningskänsliga perioderhos vissa mindre däggdjur
- 2023
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Jakt är ett av de viktigaste verktygen inom viltförvaltningen för att reglera viltstammarna, samt deras ekosystemtjänster respektive -otjänster. Jakttiderna bestäms dels utifrån behov, dels utifrån etiska hänsyn. Dessa bestäms i sin tur i stor utsträckning utifrån arternas biologi, exempelvis för att minska risken att lakterande honor skjuts från sina ungar, att jakt stör parbildningen eller att föräldradjur skjuts innan ungarna är självständiga. Här är det nödvändigt med god kunskap om viltets reproduktionstider i arbetet med att finna goda avvägningar. Vid den förra jakttidsberedningen konstaterades att jakttiderna möjligen överlappar med reproduktionstiderna för flera arter, samtidigt som potentiella kunskapsluckor identifierades. Den föreliggande rapporten syftar dels till att sammanfatta befintlig kunskap, dels till att slå fast vilka ytterligare kunskapsbehov som finns för arterna rödräv (Vulpes vulpes), grävling (Meles meles), skogsmård (Martes martes), iller (Mustela putorius), skogshare (Lepus timidus), fälthare (Lepus europaeus) och bäver (Castor fiber) inför kommande jakttidsberedningar. Författarna identifierar kunskapsluckor när det gäller reproduktionstider för samtliga arter som tas upp i rapporten. Varken jakt eller hundträning bedöms dock påverka sannolikheten att individer parar sig i “rätt tid” för någon art, medan det däremot kan finnas effekter under uppfödningsfasen. För hararna och för bäver konstateras att jakt bedrivs medan de första kullarna föds, vilket innebär en risk att lakterande honor skjuts från sina ungar. Även om de första kullarna har liten betydelse för populationstillväxten hos hararna så innebär detta självfallet ett etiskt problem om ungarna svälter ihjäl till följd av jakt. För alla tre arterna vore det önskvärt med mer och aktuell kunskap om när födslarna sker; för bävern som föder inne i hyddan kommer det dock vara mycket krävande att samla in relevanta data. Osäkerheten är större när det gäller vid vilken tidpunkt individer blir självständiga än för tidpunkten för födseln. Generellt kommer det vara extremt ut-manande att visa att det sannolikt inte finns några direkta, negativa effekter av om en förälder försvinner. Det finns en samvariation mellan latitud och reproduktionsperiod som starkt antyder att klimatet påverkat tidsmässiga anpassningar av reproduktionen på regional nivå. Det finns inga undersökningar som visar på en förändrad reproduktionstid för någon av arterna, men samtidigt saknas relevanta data för jämförelser över tid i princip genomgående. Det finns goda skäl att anta att reproduktions-tiderna kommer att förändras till följd av klimatförändringarna, men att det kommer ske i långsammare takt.
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