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The prevalence of livestock grazing in wildlife area s is increasing. This transformation of ecosys- tems into agroecosystems is concerning because the intr oduction of new species may cause niche displacement of the functionally related native species. We used a la rge-scale fence scheme and f ecal analyses to study the in fl uence of free-ranging livestock on moose diet on thr ee boreal forest ranges. We found low interspeci fi cdiet overlap between moose and livestock (mean Pianka ’ s O across ranges = 0.21, SD = 0.104), and the diet overlap with livestock did not differ between moose in areas with livestock and in adjacent control areas without live- stock. Still, moose sympatric with livestock had less fe cal nitrogen (a proxy for diet quality) than moose in the control areas. Our fi ndings suggest that interspeci fi c interactions other than direct food competition contributed to reduce the moose ’ foraging opportunities, such as altered forag e abundance and composition, or behavioral avoidance of livestock. We caution that displacement in the foodscape (i.e., spati otemporal use of food) can occur through pathways not evident in niche indices based on composition of plant species in the diet.

Sammendrag

NIBIO har på oppdrag av Gjøvik kommune og Gjøvik bestandsplanområde utført taksering av elgbeite i de skogkledde delene av kommunen i juni 2007, 2012 og 2018, for å kunne si noe om utvikling i beitetilbud og beitepress. Årets takst viser en markant økning av nylig hogst. Høydeklasse 0 (hogd siste året) utgjorde 5x mer av det takserte arealet enn typisk for våre elgbeitetakster på Østlandet. H.kl. 0 og 3, som begge har tilnærmet null elgbeite i Gjøvik, utgjorde nå til sammen 38% av arealet mot tidligere 15%. Dette gjenspeiles i redusert tilbud av beiteplanter, særlig av rognetrær (halvert tetthet). Noe av nedgangen forklares også med at vi utvidet årets takstlinjer til å bedre dekke et tverrsnitt av skogen (tidligere takster har vært noe konsentrert til de mest produktive arealene). I tillegg var forsommeren 2018 rekordtørr, og den foregående vinteren særlig snørik. Som ventet viser derfor årets takst et langt høyere beitepress enn tidligere, og betydelig over plantenes sannsynlige tålegrense for samtlige beitearter i busksjiktet. Det er derfor grunn til å advare om at elgbestanden var stor i forhold til beitenes nåværende bæreevne. Et for høyt beitepress på beiteplantene, selv over få år, kan føre til redusert beiteproduksjon som vedvarer til tross for en forventet snarlig økning i tilgang til h.kl 2. Vi har grovt beregnet beitenes nåværende bæreevne til maks 0.7 til 1.1 elg/km2 (vinterbestand), og bestanden er nå omlag 1.0 elg/km2 gitt null netto inn- og utvandring.

Sammendrag

NIBIO har på oppdrag av Vestre Toten kommune utført taksering av elgbeite i de skogkledde delene av kommunen i juni 2018, for å kunne si noe om beitetilbud og beitepress (grunntakst). Vi fant at Vestre Toten har like mye bjørk, rogn og Salix, men betydelig mindre furu og annet lauv enn øvrige områder vi har taksert på Østlandet. Vi fant et svært høyt beitepress på både rogn og Salix. Det var betydelig over plantenes sannsynlige tålegrense. Vi fant også et uvanlig høyt beitepress på bjørk, noe som kan ha vært forsterket av at forsommeren 2018 var rekordtørr og den foregående vinteren var særlig snørik (på hele Østlandet, ikke bare på Toten). Elgbestanden er for høy hvis målet er å opprettholde beiteproduksjon på både ROS og bjørk. Den synes derimot ikke for høy i forhold til det totale beitets nåværende bæreevne, forutsatt at det høye beitepresset vi nå observerte på bjørk er forbigående. Vi har grovt beregnet beitenes nåværende bæreevne til å være maks 1.0 til 1.7 elg/km2 (vinterbestand), mens bestanden nå er omlag 1.3 elg/km2 gitt null netto inn- og utvandring.

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The research literature on food selection by large herbivores is extensive. Still, we are generally lacking in our knowledge of the influence of potentially interacting chemical contents of the food. We made a qualitative review of a systematic literature search of studies that empirically link chemical contents of food to the food selection by northern cervids (genera Alces, Capreolus, Cervus, Dama, Odocoileus, Rangifer). We found that although the majority of the 98 relevant studies measuring any given food constituent (energy, protein, fiber, minerals, plant secondary metabolites) provided support for it acting as a driver of food selection (in either a negative or positive way), there was little support for the traditional hypotheses of maximization or limitation of any single constituent. Rather, because of the animals’ need to acquire an appropriate intake of several constituents at the same time, our review highlights how new empirical stud- ies need to focus on several food constituents in synchrony: (1) Study designs should capture sufficient variation in the content of food constituents in order to tease apart their many co-variations; and (2) insights about nutritional drivers may be lost if one uses only composite currencies such as crude energy, crude fiber, ash, or tannins, which may mask contrasting selection patterns of the lumped constituents. Season had an apparent influence on the selection of some food constituents, particularly various fiber frac- tions. In contrast, our review revealed a lack of evidence that cervids more strongly select for protein in summer than they do in winter. Our overall conclusion of the review is that interacting chemical contents of food make the nutritional value of a given food type into a varying entity. To better elucidate this varia- tion, we need new technologies that non-invasively capture nutrient intake of free-ranging animals, across seasons.

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The composition of plant secondary metabolites (PSMs) extensively impacts ecosystem functioning. It is vital that we understand temporal patterns in the plants’ allocation of resources to PSMs, particularly those influenced by human activity. Existing data are insufficient in the long-term perspective of perennial plants (age or ontogeny). We analysed phenolic concentrations in foliage from birch (Betula pubescens Ehr.) considered to be undamaged and growing on 5, 10 and 15 years old clear-cuts in two boreal forest landscapes in Norway, sampled at the peak of the growing season. In sum, low molecular weight phenolic concentrations decreased with age. Apart from one apigenin glycoside, the low molecular weight phenolics co-varied similarly at all ages, suggesting a lack of temporal compound-specific prioritisation of this group. In contrast, the concentration of MeOH-soluble condensed tannins increased with age. The compositional shift fits well with several hypotheses that may provide proximate explanations for age patterns in PSM allocations, including both resource constraints and external pressures. Regardless of these explanations, our study adds an important perennial perspective (plant age) to temporal PSM patterns already well-known in boreal plant phenology (foliage age).

Sammendrag

Plant defence against environmental stressors often changes dramatically as plant develop. The composition of secondary compounds (PSM) in the vegetation of a landscape has extensive influence on ecosystem functioning. It is therefore crucial that we understand how various temporal factors affect plant content of PSMs, particularly those indirectly induced and controlled by human activity. One illustrative PSM group of major ecological interest is phenolics, which serve needs as diverse as herbivory defence, pathogen resistance, allelopathy or symbioses signalling, frost and drought hardiness, and photodamage protection. I will present results from our ongoing studies of defensive chemistry of European beech (Fagus sylvatica) and birch (Betula spp) across seasons and ages, and discuss the results in relation to ecological theories and functionality of plant chemical defence.

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Despite decades of intense research, it remains largely unsolved which nutritional factors underpin food selection by large herbivores in the wild. We measured nutritional composition of birch foliage (Betula pubescens) available to, and used by, moose (Alces alces) in natural settings in two neighboring regions with contrasting animal body mass. This readily available food source is a staple food item in the diet of moose in the high-fitness region, but apparently underutilized by moose in the low-fitness region. Available birch foliage in the two regions had similar concentrations of macronutrients (crude protein [CP], fiber fractions, and water-soluble carbohydrates [WSC]), although a notably lower variation of WSC in the low-fitness region. For minerals, there were several area differences: available birch foliage in the low-fitness region had less Mg (depending on year) and P, but more Ca, Zn, Cu, and Mn. It also had higher concentrations of some plant secondary metabolites: chlorogenic acids, quercetins, and especially MeOH-soluble condensed tannins. Despite the area differences in available foliage, we found the same nutritional composition of birch foliage used in the two regions. Compared to available birch foliage, moose consistently used birch foliage with more CP, more structural fiber (mainly hemicellulose), less WSC, higher concentrations of several minerals (Ca, Zn, K, Mn, Cu), and lower concentrations of some secondary metabolites (most importantly, MeOH-soluble condensed tannins). Our study conceptually supports the nutrient-balancing hypothesis for a large herbivore: within a given temporal frame, moose select for plant material that matches a specific nutritional composition. As our data illustrate, different moose populations may select for the same composition even when the nutritional composition available in a given food source varies between their living areas. Such fastidiousness limits the proportion of available food that is acceptable to the animal and has bearings on our understanding and application of the concept of carrying capacity.

Sammendrag

Natural and rural land provides resources for the majority of ecosystem services we need. Typical provisioning services from these resources are timber logging, collection of berries, mushrooms and hunting. Typical regulating services are carbon storage, regulation of flooding and temperature, and typical cultural services are education, science and nature based tourism. The use of one ecosystem service always affects the other services. How can we evaluate how the various use of services affect each other? In our research group, we work innovatively with multi-criteria analyses to find ways of trading-off contradicting interests in ecosystem services. The red tread is to consider «all» sides of multiuse and thereby reduce conflicts between stakeholders. To achieve this, it is necessary to combine conventional valuation methods (market-oriented recourse-economy) and new socioecological approaches.

Sammendrag

EDU-ARCTIC er et nytt og nettbasert undervisningsopplegg for å lære ungdom 13-19 år om naturfag og forskning. Mer enn 300 nettbaserte foredrag formidles direktesendt, og både lærer og elev kan stille forskeren spørsmål og få svar underveis.

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Co-existing species at the same trophic level often segregate with respect to diet, habitat use, or spatial distribution, reducing their direct competition for resources. However, temporal patterns in species-specific habitat use, for instance due to climatic variation, may affect the strength of interspecific interactions, and generate temporal variation in niche partitioning. We assessed temporal variation in habitat overlap between a wild ungulate, moose Alces alces, and two freeranging domestic ungulates, sheep Ovis aries and cattle Bos taurus, on a boreal forest range in southern Norway. We also calculated the distance between species’ realised niches, as well as the width of their realised niches to evaluate the extent of temporal niche partitioning under different diurnal weather conditions. Analyses of each habitat variable suggested complex relationships between species-specific habitat use, photoperiod, and weather, related to species-specific behaviour and activity patterns. We found shorter overall niche distance between moose and sheep, compared to moose and cattle, and shorter niche distances during day and night than during the twilight hours. The niche distance between moose and sheep was positively related to temperature during night, but negatively during day. Moreover, niche distance between moose and both sheep and cattle was negatively related to precipitation at daytime. Moose niche width was narrower in periods with short niche distance to sheep, while we did not find such pattern towards cattle. A lack of similar moose response to cattle could be attributed to lower niche overlap between moose and cattle. Our results suggest that temporal niche partitioning between moose and livestock breaks down under the weather conditions that are predicted to become more common as climate change, potentially increasing wildlife-livestock interactions in the future.

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We are increasingly confronted with severe social and economic impacts of environmental degradation all over the world. From a valuation perspective, environmental problems and conflicts originate from trade-offs between values. The urgency and importance to integrate nature's diverse values in decisions and actions stand out more than ever. Valuation, in its broad sense of ‘assigning importance’, is inherently part of most decisions on natural resource and land use. Scholars from different traditions -while moving from heuristic interdisciplinary debate to applied transdisciplinary science- now acknowledge the need for combining multiple disciplines and methods to represent the diverse set of values of nature. This growing group of scientists and practitioners share the ambition to explore how combinations of ecological, socio-cultural and economic valuation tools can support real-life resource and land use decision-making. The current sustainability challenges and the ineffectiveness of single-value approaches to offer relief demonstrate that continuing along a single path is no option. We advocate for the adherence of a plural valuation culture and its establishment as a common practice, by contesting and complementing ineffective and discriminatory single-value approaches. In policy and decision contexts with a willingness to improve sustainability, integrated valuation approaches can be blended in existing processes, whereas in contexts of power asymmetries or environmental conflicts, integrated valuation can promote the inclusion of diverse values through action research and support the struggle for social and environmental justice. The special issue and this editorial synthesis paper bring together lessons from pioneer case studies and research papers, synthesizing main challenges and setting out priorities for the years to come for the field of integrated valuation.

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People provide wild ungulates with large quantities of supplementary feed to improve their health and survival and reduce forest damage. Whereas supplementary feeding can positively affect the winter survival of ungulates and short-term hunting success, some of the feeds provided may actually reduce ungulate health and increase forest damage. Here, we highlight how recent advances in ungulate nutritional ecology can help explain why supplementary feeding can lead to undesirable outcomes. Using Europe’s largest cervid, the moose (Alces alces), as a model species, and Sweden, as the socio-ecological context, we explain the concept of nutritional balancing and its relevance to supplementary feeding. Nutritional balancing refers to how animals alter their food intake to achieve a specific nutritional target balance in their diet, by selecting balanced food items or by combining items with nutritional compositions that are complimentary. As the most common supplementary feeds used contain higher concentrations of non-structural carbohydrates than the ungulates’ normal winter diet, the consumption of such feeds may cause animals to increase their intake of woody browse, and thereby exacerbate forest damage. We also explain how animal health may be negatively affected by large intakes of such feed if complementary browse items are not available. We therefore suggest that the use of inappropriate feed is an additional means by which supplementary feeding may result in negative outcomes for hunters, forest owners, and wild animals.

Sammendrag

Finding new ways to simultaneously account for monetary and non-monetary goals in ecosystem services is needed in order to establish a new modelling framework for the facilitation of trade-offs between competing stakeholder interests. The socioecological sustainability of an ecosystem service is dependent on the consent of the people in the area of the ESS. An important reason is that a given ecosystem service may have highly different value in different stakeholder cultures. In this aspect is also the understanding of disservices and hidden services. The kind and level of conflict tend to differ with location and the operational level of decision-making. It is crucial work to identify all linked subservices and organise them into a common framework for evaluation. In our research group (MULTIESS) we try to develop multi-criteria tools to assess the implications of prioritizing different interests on ecological, sociological and economic output. Similarly, changes in the human population and environment will interact and influence on the services and their values, demanding such parameters to be evaluated for the whole range of potential scenarios. We maintain that in order to make multi-criteria analyses (MCA) successful, service outputs and externalities must and can be measured in familiar terms (e.g. money, biomass) without the use of direct or stated pricing of non-commodities such as welfare, recreation or biodiversity.

Sammendrag

NIBIO har på oppdrag av Ringsaker kommune utført taksering av elgbeite i de skogkledde delene av kommunen i juni/juli 2016. Dette er en oppfølging av tilsvarende takst utført i 2015, med formål å kunne si noe om beiteproduksjon og beitepress på de enkelte jaktvald. NIBIO understreker at slike tall må brukes med forsiktighet på valdnivå, både fordi antall takstflater er få per vald og fordi det er ukjent i hvor stor grad elgens områdebruk følger valdgrenser. Tilbudet av buskbeite (lauv og furu) er lavt i alle vald sammenliknet med Østlandet for øvrig (listet fra størst til minst skuddproduksjon: Veldre, Furnes, Brøttum, RJFO, Nes), mens dekningen av beiteplanter i feltsjiktet følger Østlandet. Beitepresset (andel vinterbeita skudd) er også høyt i alle vald (listet fra størst til minst beitepress: RJFO, Veldre, Nes, Brøttum, Furnes), og trolig over de fleste planteartenes tålegrense.

Sammendrag

NIBIO har på oppdrag av Ringsaker kommune utført taksering av elgbeite i de skogkledde delene av kommunen i juni/juli 2015. Beiteproduksjonen er svært lav. Dette gjelder spesielt for vinterbeite i hele det takserte området, og for sommerbeite innenfor fellesbeitet for husdyr. I lys av at beitetrykket (andel vinterbeitet skudd) trolig er over plantenes tålegrense, anbefaler vi at tetthet av både elg og husdyr vurderes nøye, også mtp. eventuelle endringer i kondisjon på elgbestanden.

Sammendrag

Bioforsk takserte elgbeitene i Salsbruket juli 2013. Salsbruket utgjør i overkant av 500 000 sammenhengende daa med utmark i kystskogregionen av Trøndelag. Som elgbeite er området preget av lav skoggrense (200-300 moh), maritimt klima (årsnedbør 2500 mm) og harde bergarter som gir låg skogbonitet (innslag av kalk i lavere områder, hvor det er mer produktiv skog). Bjørk er den viktigste beiteplanten for elg i busksjiktet i Salsbruket (40% av tilgjengelig trær og 50% av tilgjengelig årsskudd), dernest furu og einer. Området er fattig på høyt selekterte arter som rogn og selje. Heller ikke feltsjiktet innehar mange arter med stor beiteverdi. Viktigste beiteplante i feltsjiktet er blåbærlyng, og dekningen av denne er høyere i Salsbruket (35% av arealet) enn i andre takserte områder (snitt 20%). Taksten viser et meget høyt beitetrykk, og jaktstatistikken viser en elgbestand i dårlig kondisjon. Vi anbefaler at bestanden tas ned inntil hogstaktiviteten eventuelt økes igjen. En skal være oppmerksom på at selv foryngelsesflater i Salsbruket ikke produserer mye beite for elg i nasjonal målestokk, og at hogst kraftig reduserer tilbudet av blåbærlyng.

Sammendrag

Denne rapporten sammenstiller to elgbeitetakster utført i Gjøvik i hhv. 2007 og 2012. I perioden har det vært noe mer hogst, og dermed en økning i lauvtilgang og en reduksjon av tilgang til høge urter. Ut fra stående hogstklassefordeling forventer vi at beitearealet vil være rimelig stabilt de neste 10 år. Rogn er fremdeles det viktigste innslaget i dietten til stedstro elg både sommer og vinter. Rogn tåler beiting dårlig og Gjøvikbeitene er derfor ekstra sårbare. Beitepresset på rogn ble i 2007 vurdert som høyt (70% av trærne og 67% av skudd beita). Beitepresset på rogn er redusert i perioden (ned til 49% av skudd beita), men det skyldes hovedsakelig at elgen har fått flere rogn å beite på, ikke at det er færre elg i skogen. Det har samtidig vært en svak økning i beiting på bjørk. Den intensiverte avskytningen som er i gang er fornuftig gitt det høye beitepresset, og den følger forskernes anbefaling om forebyggende forvaltning av elgstammene (unngå nedgang i kondisjon). Hvor langt ned elgstammen skal tas bør vurderes fortløpende bl.a. ut i fra endring i andel beita årsskudd (først og fremst på rogn). Vi anbefaler at årets beitetakst følges opp av en ny takst om 5 år.

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Beitetilbud, dyretetthet og skader på granforyngelse ble taksert på 56 hogstflater innenfor og utenfor sperregjerdet for husdyrbeiting i Ringsakerallmenningene i september 2012. Vi fant 1/3 så mye lauv innenfor som utenfor gjerdet, og lauvet innenfor var hardere beitet. Det er derfor minimalt med vinternæring for elg innenfor gjerdet. I feltvegetasjonen dominerer gras både innenfor og utenfor. Det tas i dag ut like mange fórenheter av storfe som av sau. Dyretettheten tilsier at det samlede beitetrykket ligger noe høyere enn den beitemessige bærevnen, først og fremst pga. antall storfe. Andel skadde granplanter var betydelig høyere innenfor (56%) enn utenfor (37%) gjerdet. Skadeandelen øker med tetthet av storfe på flata (men ikke med tetthet av sau). På de mest utsatte flatene var fire av fem planter skadd. Dagens tetthet av storfe vanskeliggjør derfor foryngelse av skogen. Et litteratursøk viser at tråkkskader i ung vekstfase sjelden gir råte som på sikt skader trærne (trærne dør enten innen kort tid eller skaden heles), men dette er studier fra 50- tallet. Forholdene (eks. klima, praksis i skogbruket) har endret seg siden da, og nye studier bør utføres.