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Global environmental changes are causing Lyme disease to emerge in Europe. The life cycle of Ixodes ricinus, the tick vector of Lyme disease, involves an ontogenetic niche shift, from the larval and nymphal stages utilizing a wide range of hosts, picking up the pathogens causing Lyme disease from small vertebrates, to the adult stage depending on larger (non-transmission) hosts, typically deer. Because of this complexity the role of different host species for emergence of Lyme disease remains controversial. Here, by analysing long-term data on incidence in humans over a broad geographical scale in Norway, we show that both high spatial and temporal deer population density increase Lyme disease incidence. However, the trajectories of deer population sizes play an overall limited role for the recent emergence of the disease. Our study suggests that managing deer populations will have some effect on disease incidence, but that Lyme disease may nevertheless increase as multiple drivers are involved.

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Denne rapporten oppsummerer resultatene fra analyser av elgens forflytnings- og trekkmønster og leveområder for 12 GPS merka elger i Stabbursdalen nasjonalpark i Porsanger kommune i 2018. Ut fra GPS-elgenes posisjoner ble det analysert forflytningsmønster, trekkdistanser, trekkruter og tidspunkt for vår- og høsttrekket, leveområdestørrelse i løpet av året og i jakttida og bruken av ulike habitatkategorier i løpet av året. I tillegg ble elgens forflytningsmønstre i forhold til inndelingen i bestandsplanområder og jaktfelt i regionen analysert. Totalt sett gir studien viktig innsikt i elgens arealbruk og kan bidra til bedre forvaltning og bevaring av elgbestanden og å sikre furuskogen i Stabbursdalen.

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Denne rapporten presenterer analyser av påkjørsler av hjort i kommunene Fjord, Stranda og Sykkylven kommuner i Møre og Romsdal. Arbeidet ble initiert i forbindelse med Sunnhjort prosjektet (2014-2019), hvor målet har vært å utvikle kunnskap om hjortens arealbruk som grunnlag for hjorteforvaltningen i regionen. I rapporten presenteres det analyser av påkjørselspunkter og hvilke faktorer som påvirker risiko for slike hendelser. I tillegg er det presentert risikokart for påkjørsler av hjort i studieområdet. Analysene er ment som et grunnlag for eventuelle tiltak langs aktuelle veistrekninger i kommunene.

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COVID-19 lockdowns in early 2020 reduced human mobility, providing an opportunity to disentangle its effectson animals from those of landscape modifications. Using GPS data, we compared movements and roadavoidance of 2300 terrestrial mammals (43 species) during the lockdowns to the same period in 2019.Individual responses were variable with no change in average movements or road avoidance behavior, likely dueto variable lockdown conditions. However, under strict lockdowns 10-day 95th percentile displacementsincreased by 73%, suggesting increased landscape permeability. Animals’1-hour 95th percentiledisplacements declined by 12% and animals were 36% closer to roads in areas of high human footprint,indicating reduced avoidance during lockdowns. Overall, lockdowns rapidly altered some spatial behaviors,highlighting variable but substantial impacts of human mobility on wildlife worldwide.

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Coprophagy, the eating of feces, has been documented in a wide range of species but appears to be rare or difficult to detect in deer (Cervidae). Here, we report the first observation of coprophagy in moose Alces alces, which was recorded using camera collars on free-ranging moose in Norway. The footage shows an instance of allocoprophagy by an adult female moose in spring (May). We summarize the current knowledge about coprophagy in deer and briefly discuss potential drivers and possible implications for disease transmission. Further research is needed to determine whether coprophagy occurs frequently in moose and whether this behavior is positive (e.g., increased intake of nutrients) or negative (increased infection by parasites or pathogens). Alces alces, camera collar, chronic wasting disease, coprophagy, foraging, moose

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Supplemental feeding of cervids during winter is a widespread management practice, but feeding may increase the risk of disease transmission. Therefore, legal regulations to limit supplemental feeding are often implemented when dealing with severe infectious diseases, such as chronic wasting disease (CWD) in cervids. However, it is currently unclear whether these regulations result in decreased spatial clustering and aggregation as intended. Supplemental feeding is expected to restrict the movement of cervids. Therefore, a ban on feeding may also result in wider space use and a risk of geographic spread of disease. The space use of 63 GPS-marked red deer (Cervus elaphus) was investigated before (n = 34) and after (n = 29) the implementation of a legal regulation aimed at limiting the supplemental feeding of cervids during winter in a CWD-affected region of Nordfjella, Norway. Snow depth was the main determinant of the space use for red deer. A moderate reduction in the number of GPS positions in spatial clusters was evident during periods of deep snow once the ban was in place. Sizes of core areas (Kernel 50%), home ranges (Kernel 95%), and dispersion (MCP 100%, number of 1 km2 pixels visited per deer) declined from January to March and with increasing snow depth. Dispersion (number of 1 km2 pixels visited per deer) did not depend on snow depth after the ban, and red deer used larger areas when snow depth was high after the ban compared to before. The ban on supplementary feeding had no effect on size of core areas or home ranges. Several potential factors can explain the overall weak effect of the ban on space use, including the use of agricultural fields by red deer, other anthropogenic feeding, and landscape topography. This study highlights that snow depth is the main factor determining space use during winter, and it remains to be determined whether the moderate reduction in spatial clustering during deep snow after the ban was sufficient to lower the risk of disease transmission.

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The management of infectious wildlife diseases often involves tackling pathogens that infect multiple host species. Chronic wasting disease (CWD) is aprion disease that can infect most cervid species. CWD was detected in reindeer (Rangifer tarandus) in Norway in 2016. Sympatric populations of red deer(Cervus elaphus) and moose (Alces alces) are at immediate risk. However, the estimation of spillover risk across species and implementation of multispecies management policies are rarely addressed for wildlife. Here, we estimated the broad risk of CWD spillover from reindeer to red deer and moose by quantifying the probability of co-occurrence based on both (1) population density and(2) habitat niche overlap from GPS data of all three species in Nordfjella,Norway. We describe the practical challenges faced when aiming to reduce the risk of spillover through a marked reduction in the population densities of moose and red deer using recreational hunters. This involves setting the popu-lation and harvest aims with uncertain information and how to achieve them.The niche overlap between reindeer and both moose and red deer was low overall but occurred seasonally. Migratory red deer had a moderate niche over-lap with the CWD-infected reindeer population during the calving period, whereas moose had a moderate niche overlap during both calving and winter. Incorporating both habitat overlap and the population densities of the respective species into the quantification of co-occurrence allowed for more spatially targeted risk maps. An initial aim of a 50% reduction in abundance for the Nordfjella region was set, but only a moderate population decrease of less than 20% from 2016 to 2021 was achieved. Proactive management in the form of marked population reduction is invasive and unpopular when involving species of high societal value, and targeting efforts to zones with a high risk ofspillover to limit adverse impacts and achieve wider societal acceptance is important. disease management, host range, moose, multihost pathogens, niche overlap, Norway,population estimation, red deer, reindeer

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Population densities of several cervid species have increased in recent decades in North America and Europe, and cervids frequently eat and damage agricultural crops. Competition and depletion of natural food resources are the main mechanisms for the density-dependent decline in vital rates of large herbivores. The extent to which access to agricultural crops can buffer density effects in cervid populations, however, is unknown. Agricultural grasslands cover more than a third of the European agricultural area, and red deer (Cervus elaphus) use these grasslands in many European countries. Over the past few decades, such grasslands have been subject to management intensification (with renewal and fertilization) in some areas and abandonment (no longer being harvested) in other areas. We used generalized linear mixed-effects models to examine the development of body masses of red deer in Norway during a period of population density increase in 16 local management units with different availability of cultivated grasslands (0.87–6.44%) in a region with active management of grasslands (Tingvoll, n = 5,780, 2000–2019) and a region with ongoing abandonment (Hitra, n = 10,598, 2007–2020). There was a consistent decline in the body mass of red deer linked to increased population density in both regions. A higher proportion of agricultural grassland was linked to higher body mass and lower density effects in both sexes and across all age classes. There is a link between body mass, survival, and reproduction. Therefore, the buffering of density effects of access to agricultural crops will fuel cervid population growth and lead to less natural regulation of abundance, making it more difficult to control dense cervid populations by harvesting.

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I denne rapporten viser vi at jegerrapporterte data gir mulighet for robust bestandsestimering av hjort basert på modellgenererte populasjonsforløp og derved mulighet for framskriving av bestandsutvikling som funksjon av jaktuttak. Tidsseriedataene, populasjonsmodellen og metoden for sammenstilling definerer til sammen en estimeringsmodell. Med utgangspunkt i data fra kommunene Averøy, Tingvoll, Surnadal og Sunndal i Møre og Romsdal viser vi hvordan en slik estimeringsmodell kan brukes til å få robuste anslag for størrelse og sammensetning av hjortebestandene på lokalt nivå.

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Hjortebeiting på skog og grasareal fører til store ­økonomiske tap for skogeigarar og bønder. Ei meir ­berekraftig forvalting av hjortebestanden er naudsynt, ­syner ny gransking.

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Many wild animals perceive humans as predators, and human disturbance,especially in the form of hunting, triggers antipredatory behavior among prey.Yet, knowledge of how game species react to different types of human distur-bance and adapt to repeated disturbances is limited. We investigated howdisturbance in the form of a solitary human approacher (stalker) impactedbehavior (flight response and short-term habitat use) of 28 GPS-collared reddeer (Cervus elaphus) in two populations with contrasting population densitiesin Norway. We studied how the behavioral response differed: (1) with season(pre-hunting vs. hunting); (2) by consecutive approaches within a day;(3) among replicated experiments within the same season; and (4) betweentwo regions with contrasting densities of red deer. The average flight initiationdistance (FID) increased by 15% during the hunting season, and consecutiveapproaches within the same day caused the red deer to move 49% longerdistances. Flight initiation distance was longer in the high-density population,while escape distance was longer in the low-density population. Red deermoved out of their weekly home range after 52% approaches, and after theonset of hunting season, time spent outside the home range increased by 89%.Red deer preferred denser resting sites after the disturbance and animal siteshad shorter sighting distance and higher canopy cover than control plots.Tree density and canopy cover at animal sites increased at the onset of huntingseason, from first to second approach within day, and after replicated experi-ments within season. Our results suggest that red deer preferred dense restingsites, especially in the hunting season. However, these animal sites had thesame amount of the favorable forage plant bilberry (Vaccinium myrtillus), indi-cating no clear food–cover trade-off in selection of habitat. Our study showedthat onset of hunting initiates stronger fear responses in red deer, which mayin turn affect red deer distribution and harvesting efficiency

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Migration of ungulates (hooved mammals) is a fundamental ecological process that promotes abundant herds, whose effects cascade up and down terrestrial food webs. Migratory ungulates provide the prey base that maintains large carnivore and scavenger populations and underpins terrestrial biodiversity (fig. S1). When ungulates move in large aggregations, their hooves, feces, and urine create conditions that facilitate distinct biotic communities. The migrations of ungulates have sustained humans for thousands of years, forming tight cultural links among Indigenous people and local communities. Yet ungulate migrations are disappearing at an alarming rate (1). Efforts by wildlife managers and conservationists are thwarted by a singular challenge: Most ungulate migrations have never been mapped in sufficient detail to guide effective conservation. Without a strategic and collaborative effort, many of the world’s great migrations will continue to be truncated, severed, or lost in the coming decades. Fortunately, a combination of animal tracking datasets, historical records, and local and Indigenous knowledge can form the basis for a global atlas of migrations, designed to support conservation action and policy at local, national, and international levels.

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Simple Summary Chronic Wasting Disease is a deadly infectious disease affecting cervids that was discovered in Norway in 2016. CWD can transmit through environmental reservoirs and aggregation and spatial clustering of animals may affect transmission. Deer usually forage on scattered forage, but anthropogenic food sources are often concentrated in space, leading to spatial aggregation. We determined what caused red deer to revisit the same locations in the environment, and the extent to which this was caused by anthropogenic food sources. We document that the most visited sites were indeed anthropogenic, which opens potential avenues to disease mitigation. Abstract Herbivores like cervids usually graze on widely scattered forage, but anthropogenic food sources may cause spatial revisitation and aggregation, posing a risk for transmission of infectious diseases. In 2016, chronic wasting disease (CWD) was first detected in Norway. A legal regulation to ban supplemental feeding of cervids and to fence stored hay bales was implemented to lower aggregation of cervids. Knowledge of further patterns and causes of spatial revisitation can inform disease management. We used a recently developed revisitation analysis on GPS-positions from 13 red deer (Cervus elaphus) to identify the pattern of spatial clustering, and we visited 185 spatial clusters during winter to identify the causes of clustering. Anthropogenic food sources were found in 11.9% of spatial clusters, which represented 31.0% of the clusters in agricultural fields. Dumping of silage and hay bales were the main anthropogenic food sources (apart from agricultural fields), and unfenced hay bales were available despite the regulation. The probability of the clusters being in agricultural fields was high during winter. It may be necessary to find other ways of disposing of silage and enforcing the requirement of fencing around hay bales to ensure compliance, in particular during winters with deep snow.

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kunnskap om hjortens arealbruk på indre Sunnmøre til grunnlag for hjorteforvaltningen i regionen. Rapporten tar også for seg påkjørsler av hjort i studieområdet og det er gjennomført analyser av risiko for påkjørsler. Rapporten oppsummerer resultatene fra prosjektet og diskuterer disse i lys av hjorteforvaltningen.

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Hjortebestanden har økt i størrelse de siste 40 årene, og hjorten har stadig inntatt nye områder i Sør-Norge. Siden år 2000 er fellingen av hjort om lag fem-doblet i Telemark, mens den i Agder er tidoblet. Bestandstettheten er foreløpig på langt nær slik som på Vestlandet, men hjorten er likevel et betydelig innslag i faunaen i de tre fylkene. I ei tid hvor hjorten blir et stadig viktigere jaktobjekt i mange kommuner i Agder og Telemark, vil en samkjørt forvaltning over større areal være en stor fordel. Gjennom Sørhjort-prosjektet har en økt kunnskaps-grunnlaget for å kunne jobbe mot en bedre forvaltning av hjortebestanden.

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Individual age is an important element in models of population demographics, but the limitations of the methods used for age determination are not always clear. We used known-age data from moose (Alces alces), red deer (Cervus elaphus), semi-domestic reindeer (Rangifer tarandus tarandus) and Svalbard reindeer (Rangifer tarandus platyrhynchus) to evaluate the accuracy and repeatability of age estimated by cementum annuli analysis of longitudinally sectioned permanent incisors. Four observers with varying experience performed blind duplicate age estimation of 37 specimens from each cervid. The relationship between known age and estimated age was linear, except for Svalbard reindeer where a quadratic model gave a slightly better fit. After correcting for observer ID and animal ID, there was a slightly declining probability to assess the correct age with increasing age for moose, red deer and Svalbard reindeer. Across cervids and observers, estimated age equalled known age in 69% of all readings, while 95% age ± 1 year. Predicted probability of correct age assessment for experienced observers was 93% for red deer, 89% for Svalbard reindeer, 84% for moose and 73% for semi-domestic reindeer. Regardless of observer experience and cervid, there was a high agreement between repeated assessments of a given animal’s tooth sections. The accuracy varied between cervids but was generally higher for observers with former ageing experience with a given cervid. We conclude that the accuracy of estimated age using longitudinally sectioned incisors is generally high, and even more so if performed by observers with former ageing experience of a given species. To ensure consistency over time, a reference material from known-age individuals for each species analysed should be available for calibration and training of observers. Age determination . Cementumannuli analysis (CAA) . Moose . Red deer . Reindeer . Incremental layer

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Nematodes of the genera Elaphostrongylus and Dictyocaulus are associated with disease in semi-domesticated tundra reindeer and farmed red deer whereas less knowledge exists in the wild. Their first stage larvae (L1) develop to the infective third stage (L3) in the environment; Elaphostrongylus spp. within intermediate gastropod hosts and Dictyocaulus spp. as free-living larvae. Larval development of Elaphostrongylus is highly temperature dependent with a developmental minimum of 9–10 °C. Larval development of Dictyocaulus spp. may occur at low temperatures (5 °C) but the larvae are sensitive to desiccation. We examined the prevalence and intensity of Elaphostrongylus spp. and Dictyocaulus spp. infections in six wild reindeer and two wild red deer populations in relation to altitude, temperature and rainfall in their respective main summer pasture area over the 5 summers prior to sampling. The parasitological examination was based upon morphological identification of L1 in the faeces of hunted animals. Altitude was calculated from animal position data and temperature and precipitation by means of a nationwide gridded data set. Temperature decreased with increasing altitude, from 13.3 °C for the lowest located red deer population (300 m) to 6.1 °C for the highest located reindeer population (1400 m). No significant relationship between altitude and rainfall was identified. Elaphostrongylus spp. infection decreased in prevalence with increasing altitude, being identified in 89% of investigated samples from the lowest located population and in 3% of samples from the highest. The prevalence of Dictyocaulus spp. infection varied between 28 and 80% and no relationship with altitude was found. The intensity of Elaphostrongylus spp. infection was low in reindeer and moderate in red deer whereas the intensity of Dictyocaulus spp. infection was moderate in both species. Our results indicated that the climatic conditions in all areas studied were suitable for Dictyocaulus spp., whereas summer temperature was a restrictive factor for Elaphostrongylus sp. in reindeer.

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Reindeer-train-collisions (RTC) are a challenge for Norwegian society and the northern Norwegian train company Bane NOR with regard to animal welfare, wildlife ecology, animal husbandry, reindeer herding and the working environment for train drivers and employees of Bane NOR. On behalf of Bane NOR the Norwegian Institute of Bioeconomy Research (NIBIO) investigated putative technological solutions to improve RTCs. The study is a result of literature research, interviews with Bane NOR employees, reindeer herders, researchers, companies and road administration project leaders and an analysis of Bane NOR´s own database of animal-train-collisions. The RTC records of the last 11 years (jan 2008 – dec 2018) revealed that prioritizing preventive measures against collisions with female reindeer along the Saltfjellet region during winter, especially during the Arctic night, are most promising. This also happens to be the most damaging time of the year for reindeer herders as they struggle to find damaged animals in the dark. Expensive and timeconsuming search efforts are a major concern with regard to animal welfare. Additionally, damaged animals are often – if at all – found long after the accident and can not be brought into Connection with a specific RTC, i.e. the herders can not claim monetary compensation…….

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With climate change, the effect of global warming on snow cover is expected to cause range expansion and enhance habitat suitability for species at their northern distribution limits. However, how this depends on landscape topography and sex in size-dimorphic species remains uncertain, and is further complicated for migratory animals following climate-driven seasonal resource fluctuations across vast landscapes. Using 11 years of data from a partially migratory ungulate at their northern distribution ranges, the red deer (Cervus elaphus), we predicted sex-specific summer and winter habitat suitability in diverse landscapes under medium and severe global warming. We found large increases in future winter habitat suitability, resulting in expansion of winter ranges as currently unsuitable habitat became suitable. Even moderate warming decreased snow cover substantially, with no suitability difference between warming scenarios. Winter ranges will hence not expand linearly with warming, even for species at their northern distribution limits. Although less pronounced than in winter, summer ranges also expanded and more so under severe warming. Summer habitat suitability was positively correlated with landscape topography and ranges expanded more for females than males. Our study highlights the complexity of predicting future habitat suitability for conservation and management of size-dimorphic, migratory species under global warming.

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Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-Depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.

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Ongoing global warming is now affecting migratory cycles in a large variety of taxa in seasonally variable environments. Disruption of migratory systems can cause population decline and affect ecosystem function across the globe. It is therefore urgent to understand the drivers of migration and how the different fitness limitations of the sexes affect migration, but studies seldom considered the full annual cycle. We analysed the annual migration cycle of 237 red deer (Cervus elaphus) in Norway and investigate how different seasonal limitations affected the variation in a suite of migration characteristics. We found fundamental differences in migration phenology between seasons, and migratory traits were much more variable in males. Spring migratory movements were characterized by longer distance roamed, lower speed, lasted longer, more frequent use of stopovers, timing was more synchronized and coincided with onset of plant growth, and with higher daily activity levels. Timing of autumn migration was more variable and not closely related to cease of plant growth. Our study emphasizes the benefits of studying the full annual cycle to gain further insight into the migration process, and how understanding the limitations of the full annual migration process of both sexes is critical for conservation purposes.

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Denne rapporten oppsummerer Sørhjort – merke- og utviklingsprosjekt for hjort i Agder og Telemark (2015-2019). Prosjektets mål har vært å utvikle kunnskap om hjortens arealbruk på Sørlandet og i Telemark til grunnlag for hjorteforvaltningen i regionen. Rapporten presenterer resultatene fra prosjektet.

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Partial migration is common in a large variety of taxa in seasonally variable environments. Understanding the mechanisms underlying migration is important, as migration affects individual fi tness. Migratory herbivores bene fi t from delayed forage maturation and hence higher food quality during migra- tion and at their summer range, termed the forage maturation hypothesis (FMH). The link between diet quality and rumination time allows migrants eating a higher quality diet to spend less time on rumination, and they can thus allocate more time to additional feeding. However, such an argument implicitly assumes that deer are energy maximizers, while studies have reported also time minimization strategies under risk of predation. Male and female distributions are limited by different factors linked to both body size differ- ences and reproductive strategies, but there is no study investigating differences in activity pattern accord- ing to the individual migratory patterns for male and female deer. We here unify the FMH with the hypotheses predicting sex-speci fi c time allocation strategies. To test predictions of sex-speci fi c activity of resident and migratory red deer ( Cervus elaphus ), we analyzed activity data of 286 individuals that were fi tted with GPS collars from a population in western Norway. While migrants were more active during the migration itself, we found no differences in activity pattern between migrant and resident deer during the main growth season, neither in terms of proportion of daily time active nor in terms of daily mean movement speed, thus rejecting that deer were energy maximizers. Overall, we found that females were more active during the main growth season even after controlling for body size differences. These patterns are consistent with patterns predicted from sexual segregation theory linked to the reproductive strategy hypothesis. Our study highlights how the understanding of migration can be advanced by considering it in the context of different reproductive strategies of males and females.

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1. Population-level management is difficult to achieve if wildlife routinely crosses administrative boundaries, as is particularly frequent for migratory populations. However, the degree of mismatch between management units and scales at which ecological processes operate has rarely been quantified. Such insight is vital for delimiting functional population units of partially migratory species common in northern forest ecosystems. 2. We combined an extensive dataset of 412 GPS-marked red deer (Cervus elaphus) across Norway with information on the size and borders of two administrative levels, the governmental level (municipality) and landowner level (local management units, LMUs), to determine the timing and scale of mismatch between animal space use and management units. We analysed how landscape characteristics affected the use of management units and the timing and likelihood of crossing borders between them, in an effort to delineate more appropriate units in various landscapes. 3. Median municipality size could potentially cover 70% of female and 62% of male annual ranges, while only 12% and 4% of LMUs were expansive enough to accommodate migratory routes in females and males, respectively. Red deer migrate along elevational gradients and are more likely to find both suitable lowland winter habitat and higher summer habitat within management units with variable topography. Consistent with this, the likelihood of border crossing decreased with increasing diversity of elevations. 4. Synthesis and applications. We demonstrate a considerable mismatch between animal space use and management units. Far-ranging movements and frequent administrative border crossings during autumn migration coincides with the period of active management (hunting season). Our study also highlights that, due to extensive movements of males, coordination of management aims may provide a more realistic avenue than increasing sizes of local management units. A more general insight is that the degree of mismatch between range use and management units depends on the season and landscape type. This needs to be accounted for when delimitating functional population units of migratory populations.

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Large herbivores gain nutritional benefits from following the sequential flush of newly emergent, high- quality forage along environmental gradients in the landscape, termed green wave surfing. Which landscape characteristics underlie the environmental gradi-ent causing the green wave and to what extent landscape characteristics alone explain individual variation in nutritional benefits remain unresolved questions. Here, we com-bine GPS data from 346 red deer (Cervus elaphus) from four partially migratory popula-tions in Norway with the satellite- derived normalized difference vegetation index (NDVI), an index of plant phenology. We quantify whether migratory deer had access to higher quality forage than resident deer, how landscape characteristics within sum-mer home ranges affected nutritional benefits, and whether differences in landscape characteristics could explain differences in nutritional gain between migratory and resident deer. We found that migratory red deer gained access to higher quality forage than resident deer but that this difference persisted even after controlling for land-scape characteristics within the summer home ranges. There was a positive effect of elevation on access to high- quality forage, but only for migratory deer. We discuss how the landscape an ungulate inhabits may determine its responses to plant phenol-ogy and also highlight how individual behavior may influence nutritional gain beyond the effect of landscape.

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Global environmental changes are causing Lyme disease to emerge in Europe. The life cycle of Ixodes ricinus, the tick vector of Lyme disease, involves an ontogenetic niche shift, from the larval and nymphal stages utilizing a wide range of hosts, picking up the pathogens causing Lyme disease from small vertebrates, to the adult stage depending on larger (non-transmission) hosts, typically deer. Because of this complexity the role of different host species for emergence of Lyme disease remains controversial. Here, by analysing long-term data on incidence in humans over a broad geographical scale in Norway, we show that both high spatial and temporal deer population density increase Lyme disease incidence. However, the trajectories of deer population sizes play an overall limited role for the recent emergence of the disease. Our study suggests that managing deer populations will have some effect on disease incidence, but that Lyme disease may nevertheless increase as multiple drivers are involved.

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Background: Many wingless ectoparasites have a limited capacity for active movement and are therefore primarily dependent on hitchhiking on their hosts for transportation. The distribution of the tick Ixodes ricinus is expected to depend mainly on transportation by hosts and tick subsequent survival in areas where they drop off. In Europe, the most important hosts of adult female I. ricinus are cervids. The extensive space use of large hosts provides a much larger dispersal potential for I. ricinus than that of smaller mammalian hosts. We aim to determine the contribution of red deer (Cervus elaphus) space use on the spatial distribution of I. ricinus, after accounting for landscape factors. Methods: We analysed the spatial distribution of I. ricinus with generalised mixed effects models (GLMMs) based on data from extensive field surveys of questing density in two coastal regions in Norway, from which home range data from 73 red deer with GPS collars were available. Red deer home ranges were derived using the kernel method to identify areas most frequently used by deer. We first fitted a baseline model with tick questing densities relative to landscape features that are likely to affect local climate conditions and hence, survival. We then added deer space use variables to the baseline model with only landscape variables to test whether areas more frequently used by red deer had higher questing tick densities. Results: Questing I. ricinus density was predicted by several landscape features, such as elevation, distance to the fjord and topographic slope. In addition, we found that areas more heavily used within the red deer home ranges, correlated with higher questing tick densities. Increased effects of deer space use were additive to the landscape model, suggesting that correlations were more than just shared landscape preferences between deer and ticks. Conclusions: Our results imply that the distribution of I. ricinus is controlled by a complex set of factors that include both local conditions related to landscape properties that affect survival and how the large host population redistributes ticks. In particular, we have provided evidence that the local distribution of large hosts, with their extensive space use, redistributes ticks at the local scale.

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De tørre og varme værforholdene med mye vind langs kysten på Vestlandet og i Trøndelag vinteren 2014 førte til en kraftig uttørking av en del plantearter, og det ble observert store områder med inntørka og død vegetasjon. Uttørkingen omfattet spesielt arter med vintergrønne blader (tyttebær), samt løvfellende planter der den overjordiske stengelen er levende (blåbær, og røsslyng). Slike fenomen omtales gjerne som klimastress og viser at planter i nordlige områder kan være sårbare for ekstreme værhendelser, spesielt høye temperaturer vinterstid. Blåbær er ei viktig plante for mange arter, fra store beitedyr til små insekter, og er en basisplante i mange næringskjeder. Endringer i blåbærlyngens biomassse kan derfor ha konsekvenser for mange andre arter...

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Understanding the responses of ecological communities to perturbation is a key challenge within contemporary ecology research. In this study we seek to separate specifi c community responses from general community responses of plant communities to exclusion of large cervid herbivores. Cervid herbivory and forestry are the main drivers of vegetation structure and diversity in boreal forests. While many studies focus on the impact of cervids on trees, a high proportion of the biodiversity and ecosystem services in boreal forests is found in the fi eld layer. However, experimental approaches investigating the infl uence of herbivory on understory vegetation are highly localised. In this study we use a regionalscale design with 51 sites in four boreal forest regions of Norway, to investigate the infl uence of cervid herbivory on the physical and ecological structure of fi eld layer vegetation. Our study sites cover a range of forest types diff ering in productivity, management and dominant cervid species, allowing us to identify generic responses and those that are specifi c to particular conditions. We found that the height of the fi eld layer and the abundances of individual species were most susceptible to change following short-term cervid exclusion across diff erent forest types and cervid species. Total vegetation density and vascular plant diversity did not respond to cervid exclusion on the same time scale. We also found that the fi eld-layer vegetation in clear-cut forests used by moose was more susceptible to change following cervid exclusion than mature forests used by red deer, but no strong evidence that the response of vegetation to herbivore exclusion varied with productivity. Our study suggests that the parameters that respond to cervid exclusion are consistent across forest types, but that the responsiveness of diff erent forest types is idiosyncratic and hard to predict.

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Browsing by cervids plays a key role in structuring forest ecosystems and dynamics. Many boreal forest systems are managed for timber resources, and at the same time the wild cervid populations are also harvested. Thus, the determination of sustainable densities of cervids for the purpose of forest and game management is challenging. In this study we report on a red deer (Cervus elaphus) exclosure experiment in the mature forests of Western Norway. Ten pairs of exclosures and browsed plots were initiated in 2008. The rate of browsing and height growth of marked individuals was recorded annually, and the total densities of all tree species assessed over the following 4 y. We found that height growth of rowan (Sorbus aucuparia) saplings (1 m tall), the most numerous tree species at the site, was prevented when 20% of the shoots were browsed. Outside of the exclosures, net height growth of rowan saplings tended to be positive when trees were below 40 cm in height, but growth was constrained in rowan saplings over this height. The density of rowan also increased in both treatments, showing that recruitment was occurring, but the increase was greater where browsed than in the exclosure. The increase in density of rowan, combined with the curtailment of height growth in the presence of red deer, serves to create a carpet of short stature rowan saplings. This has parallels with the browsing lawn concept, but it seems to occur in interaction with snow depth; individuals protruding above the snow layer are likely to be browsed during the winter, whilst smaller individuals are protected during this season, when browsing is at its peak. Keywords: browsing lawns, Cervidae, Cervus elaphus, herbivory, snow depth, sustainable management. Résumé : Le broutement par les cervidés joue un rôle clé dans la composition, la structure et la dynamique des écosystèmes forestiers. De nombreux systèmes forestiers boréaux sont gérés à la fois pour la production de ressources ligneuses et la chasse sportive des cervidés. Un enjeu majeur réside dans la détermination d’une densité de cervidés permettant une exploitation durable de ces ressources. Dans cette étude, nous rapportons une expérience d’exclusion du cerf élaphe (Cervus elaphus) dans les forêts matures de l’ouest de la Norvège basée sur 10 paires d’exclos et de parcelles accessibles au broutement établies en 2008. Nous avons mesuré annuellement durant 4 ans le taux de broutement et de croissance verticale de semis et de gaulis marqués et estimé les densités totales de toutes les espèces d'arbres. Hors des exclos, la croissance des gaules (1 m de haut) de sorbier des oiseleurs (Sorbus aucuparia), l’espèce ligneuse la plus abondante sur le site, était compromise lorsque 20 % des pousses étaient broutées. Nous avons observé une tendance positive dans la croissance des gaules de moins de 40 cm alors qu’elle était compromise au-delà de ce seuil. La densité de sorbiers a également augmenté à l’intérieur et à l’extérieur des exclos révélant un recrutement positif, toutefois l'augmentation de la densité était plus marquée dans les parcelles soumises au broutement. L'augmentation de la densité de sorbiers, combinée à la réduction de la croissance en hauteur, en présence du cerf élaphe génère une strate dense de sorbiers de petite stature. Cette situation présente des similitudes avec le concept de haie de pâturage (browsing lawn), mais pourrait être liée à l’épaisseur de neige au sol. En effet, les arbustes qui dépassent la couche nivale sont plus susceptibles d’être broutés que les plus petits qui sont protégés en hiver lorsque la consommation d’espèces ligneuses est maximale. Mots-clés : cervidés, Cervus elaphus, épaisseur de neige, exploitation durable, haie de pâturage, herbivorie

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This paper presents a bioeconomic analysis of a red deer population within a Norwegian institutional context. This population is managed by a well-defined manager, typically consisting of many landowners operating in a cooperative manner, with the goal of maximizing the present-value hunting related income while taking browsing and grazing damages into account. The red deer population is structured in five categories of animals (calves, female and male yearlings, adult females and adult males). It is shown that differences in the per-animal meat values and survival rates (‘biological discounted’ values) are instrumental in determining the optimal harvest composition. Fertility plays no direct role. It is argued that this is a general result working in stage-structured models with harvest values. In the numerical illustration it is shown that the optimal harvest pattern stays quite stable under various parameter changes. It is revealed which parameters and harvest restrictions that is most important. We also show that the current harvest pattern involves too much yearling harvest compared with the economically efficient level.

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Undersøkelsen ble gjennomført ved bruk av spørreskjema. Målgruppen var aktive hjorteviltje-gere med varierende erfaringsgrunnlag og geografisk tilhørighet. Totalt 967 utvalgte hjortejege-re fra Hordaland ble trukket ut og vi fikk svar 577 svar (59,7 %). En ikke-respons sjekk viste at representativiteten til utvalget var meget god i forhold til de som hadde svart og de som ikke hadde svart. Generelt var kvinner som jaktet hjort yngre enn menn, med en gjennomsnittsalder på henholdsvis 39,7 år for kvinner og 47,5 år for menn. Bare 21 % hadde under 5 års erfaring med hjortejakt. Av de som jaktet hjort i 2010, var det hele 33 % som oppga å ha jaktet mer enn 21 dager, mens 11 % jakter inntil 5 dager. Jegerne i Hordaland jakter vanligvis sammen med venner (42 %) og familie (26 %). Gjennomsnittlig størrelse på jaktlaget var 6 personer, men vanligvis deltar mellom 4- 5 personer. Jegerne svarer at de ikke er overbeviste om at tilgangen og tilrettelegging for jakt er bedret, men de var mer enige om påstanden om at fokuset på å tjene penger på jaktsalg har økt. Det var mest vanlig å få tilgang til et jaktområde fordi man er grunneier selv (56 %), eller at man har fast tilgang til jaktområde (42 %). Om lag 1/3 av jegerne oppga å ha felt hjort. Vi fant et gjennomsnittsforbruk knyttet til hjortejakta i 2010 på henholdsvis 6195 NOK (± S.E. 804) for grunneiere og 8258 NOK (± S.E. 1157) for andre jegere. Gjennomsnittlig kostnad per felte hjort var 3367 NOK (± S.E. 271) alle typer dyr sett under ett. 62 % av jegerne svarte at de betalte for jakten, mens resten svarte at de ikke betalte noe for jakttilgangen. Den vanligste måten å beta-le for hjortejakta i Hordaland er stykkpris per løyve, uavhengig av type dyr. Om lag hver fjerde jeger betaler stykkpris som varierer ut i fra type dyr, eller betaler for jakta på andre måter. Vi fant at nesten halvparten av jegerne var villige til, eller ønsker, en variabel pris etter hvilken tid på jaktsesongen man er inne i. Omtrent hver femte jeger mener at intervallet mellom 21-40 kg er passe mengde kjøtt til egen bruk i husholdningen, mens litt over hver fjerde jeger mener at mer enn 50 kilo med hjortekjøtt er passe mengde kjøtt til eget bruk. Jegerne var mest enige i påstanden om at det er mye hjort i terrenget i deler av jaktsesongen, deretter skårer påstandene at «å reise bort sammen med familie/venner for å jakte hjort er en del av selve jaktopplevelsen». Samtidig får påstanden «Jeg jakter på egen eiendom og bor hjemme når jeg jakter hjort» en relativt høy skår. Det vil si, som allerede påvist, at mange av respondentene er grunneiere og jakter på egen eiendom. Jegerne er minst enige i påstandene om at de har problemer med å skaffe seg hjortejakt der de ønsker å jakte. De synes heller ikke at det er langt å reise til områder med god hjortejakt. NØKKELORD : hjortevilt, hjort (Cervus elaphus), spørreundersøkelse, jegere, jakt, large ungulates, red deer (Cervus elaphus), questionnaire, hunters, hunting

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Hovudmålsetjinga med prosjektet ”Kostar hjorten meir enn han smakar?” er å utvikle metodar for å berekne inntekter og utgifter som hjorten representerer for den enkelte grunneigar, og samla innafor eit avgrensa område (storvald). Som referansevald for berekningar av nytte- og kostnadsverdi har ein nytta Eikås storvald i Jølster kommune. I valdet vart skadeomfanget etter beiting av hjort berekna på all innmark og all granskog i hogstklasse III og IV, samt furu i hkl II. Verdien på ein foreining grovfôr vart relatert til prisen på kraftfôr med eit fråtrekk for sparte haustekostnadar, og fastsett til 2,28 kr. Når ein la denne prisen til grunn vart avlingstapet berekna til 109 kr pr daa i snitt for all innmark i valdet. I desse berekningane har ein teke omsyn til kostnadar knytt til auka behov for engfornying og ein har teke omsyn til at beiting i attleggsåret gir eit avlingstap som vert akkumulert i dei etterfølgjande engåra. Resultatet for skog synte at dei årlege kostnadane på gran i hkl III og IV i snitt var kr 26,60 pr daa og på furu kr 2,80 pr daa, når ein legg til grunn veksetida fram til kulminasjon og hogst. Desse resultata er først og framt gyldige for Eikåsvaldet med dei tilhøva ein finn der i høve til bestandstettleik av hjort, arealfordeling og korleis jord- og skogbruk vert praktisert ved dyrking av eng og skjøtsel av skog, mellom anna så er truleg resultatet frå furu noko lågt på grunn av underoptimalt tretal i dei takserte bestanda. Det samla skadeomfanget i valdet vart samanstilt med inntektene generert gjennom jakt og utleige av jaktløyve. Dette ga eit knapt overskot for valdet på 33 839 kr pr år.

Sammendrag

Målet med rapporten er å kunne:Beskrivelse av utvikling av bestanden og estimere en sannsynlig bestand før jakt 2009 i Jølster kommune.Beskrive ulike scenarioer om hvordan bestanden vil endre seg ved ulike avskytingsmønster framover i tid.Gi noen anbefalinger for forvaltningen av hjort i Jølster.Rapporten viser sammenstillinger over ulike typer materiale fra Jølster kommune. For modellering av bestand, og som grunnlag for utarbeiding av scenarioer, har vi brukt en deterministisk bestandsmodell og definert et utgangspunkt for antall dyr i bestanden fordelt på ulike aldersklasser og kjønn. Både sett hjort registreringene og avskytningstalla tyder på en vesentlig økning i hjortebestanden i løpet av de senere åra. I løpet av åra fra 1990 til 2002 økte avskytningen i snitt med 12,4 % årlig, noe som indikerer en høy bestandsvekst. Avskytningen har også økt mye de siste par åra (12,8 % i 2008 og 10,3 % i 2007) etter noen år med relativt jevnt uttak (2002-2006), og gjennomsnittlig årlig økning i uttaket er i perioden 2002-2008 på 3,9 %, noe som er "mer" normalt. Sett hjort registreringene tyder på sammensetningen i bestanden er rimelig stabil. Hvis man sammenholder denne utviklingen (stabil andel bukker) med at den faktiske avskytningen som har en overvekt av hanndyr i uttaket, så tyder dette også på en økning i bestandsstørrelsen (eller en relativ høy positiv innvandring av bukk til deler eller hele kommunen). Sett hjort talla tyder på en noe variasjon i rekruttering til bestanden mellom åra, men trenden er stabil selv om gjennomsnittsvekta er nedadgående for de yngre kollene. Både avskytningsmønsteret og alderssammensetninga blant felte dyr kan tyde på en noe lav snittalder i stående bestand, på grunn av lav felling av unge dyr (les kalver) relativt sett over tid. Ut i fra de modellforutsetningene beskrevet ovenfor og gitt en bestandsøkning på 3-7 % årlig i løpet av de siste 6 åra, har vi beregna at Jølster kommune har en sannsynlig bestandsstørrelse (jaktbestand) 2800 ± 200 dyr før jakt i 2009. Denne bestandsstørrelsen vil kunne være grunnlag for et årlig uttak av 473-756 ± 70 dyr i åra framover avhengig av mål og strategier som blir lagt. Rapporten inneholder i tillegg noen anbefalinger for Jølster kommune sin hjorteforvaltning for åra som kjem.

Sammendrag

Det foregår en historisk stor satsning for å øke kunnskapen om hjorten og hjortens areabruk i Norge. For tida er det flere regionale prosjekter som undersøker hjortens arealbruk med bruk av GPS halsbånd. Det foregår også et forskningsprosjekt som samler og setter de regionale prosjektdataene inn i en større sammenheng. Vi håper på et "kvantesprang" i kunnskapen om hjorten i åra som kommer!

Sammendrag

Denne rapporten omhandler forvaltningen av hjortevilt og spesielt hjort i Haram kommune. Det er gjort en gjennomgang av forvaltningen av hjort(hjortevilt), og vi kommer med en del vurderinger og konkrete anbefalninger i det videre arbeidet med kommunale mål og rammer. På slutten av rapporten kommer vi med forslag til en del konkrete mål og tiltak i hjorteviltforvaltningen i Haram kommune.

Sammendrag

Målet med rapporten er å kunne: " Beskrivelse av bestandsforholdene for hjort med kjønns- og alderssammensetning og bestandsestimat før jakt 2008. " Beskrive ulike scenarier om hvordan bestanden vil endre seg ved ulike avskytingsmønster framover i tid. " Komme med anbefalinger for framtidig forvaltning av hjort i Gloppen. Rapporten viser sammenstillinger over ulike typer materiale fra Gloppen kommune. For modellering av bestand, og som grunnlag for utarbeiding av scenarier, har vi brukt en deterministisk bestandsmodell og definert et utgangspunkt for antall dyr i bestanden fordelt på ulike aldersklasser og kjønn. Gloppen kommune hadde sannsynligvis hatt en på en stor økning i bestanden i løpet av 1990-tallet og fram til om lag 1998. Da fulgte en del åra med en mer eller mindre utflating av uttaket og sannsynligvis også bestanden. Ut fra avskytningen og overvåkningsdata ser det ut til at bestandens igjen har økt noe de siste par åra. Overvåkningsdataene (innmarkstellingene og sett hjort) tyder på en økning i andelen bukk i bestanden de senere åra. Hvis man sammenholder denne utviklingen (økt andel bukk) med at den faktiske avskytningen, som har en overvekt av hanndyr i uttaket, så tyder dette også på en økning i bestandsstørrelsen. Både sett hjort og innmarkstellingene tyder på en variasjon i rekruttering til bestanden mellom åra, men usikkerheten i disse talla er foreløpig relativt stor. Ut fra de forutsetningene vi har satt i bestandsmodellen sammenholdt med avskytningstall og overvåkningsdata har Gloppen kommune en sannsynlig (jakt) bestand før jakt i 2008 på 3000 ± 300 dyr. Denne bestanden kan gi et bærekraftig uttak i 2008 på 630-735 ± 60 hjort avhengig av hvilke mål man har for bestandsutviklingen framover. Rapporten inneholder i tillegg noen anbefalinger for Gloppen kommune sin hjorteforvaltning for åra som kjem.

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Fra tidlig på 1970-tallet har den norske hjortebestanden blitt mer enn 10-doblet, og hjortejakta 2007 resulterte i nok en avskytningsrekord på over 32 600 felte hjort. Selv om veksten har vært kraftigst i de tradisjonelle hjorteområdene på Vestlandet og i Trøndelag, er hjorten i dag representert i de aller fleste kommuner sør for Saltfjellet. Sannsynligheten er stor for at mange av kommunene utenfor de tradisjonelle hjorteområdene vil oppleve en betydelig bestandsvekst i årene som kommer. For mange jaktrettshavere og jegere vil dette representere nye muligheter for næringsmessig utnytting av utmarka og utøvelse av jakt. På samme tid vil det dukke opp nye utfordringer knyttet til den lokale forvaltningen hjorten.

Sammendrag

Fra tidlig på 1970-tallet har den norske hjortebestanden blitt mer enn 10-doblet, og hjortejakta 2007 resulterte i nok en avskytningsrekord på over 32 600 felte hjort. Selv om veksten har vært kraftigst i de tradisjonelle hjorteområdene på Vestlandet og i Trøndelag, er hjorten i dag representert i de aller fleste kommuner sør for Saltfjellet. Sannsynligheten er stor for at mange av kommunene utenfor de tradisjonelle hjorteområdene vil oppleve en betydelig bestandsvekst i årene som kommer. For mange jaktrettshavere og jegere vil dette representere nye muligheter for næringsmessig utnytting av utmarka og utøvelse av jakt. På samme tid vil det dukke opp nye utfordringer knyttet til den lokale forvaltningen hjorten.

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Denne rapporten oppsummerer en beitekartlegging gjennomført på Søre-Sunnmøre. Hensikten har vært å utføre en kartlegging av viktige vinterbeiteområder for hjort i kommunene Ørsta, Volda, Hareid, Sande, Herøy og Ulstein. Våre resultater viser at totalt sett var blåbærlyng den mest utbredte av lyngartene, men at det er forskjell mellom områdene i mengde tilgjengelig. Blant trea var bjørk, einer, furu, gran, gråor og rogn de mest utbredte og tilgjengelige artene, men de produserer høyst ulikt antall skudd pr flate. Rogn var hardest beita av trea og blåbæra av lyngen. Det var til dels betydelig variasjon mellom områdene (blokkene) i beitefrekvens, men det var også en betydelig variasjon innen områdene. Resultatene viser at beitetrykket totalt sett er moderat i de undersøkte områdene, men det er en variasjon både mellom og innad i de undersøkte områdene. Enkelte områder er utsatt for et så høyt beitetrykk at man kan forvente en endring både i vegetasjonsstrukturen og beiteproduksjonen på sikt på disse lokale områdene. I de enkelte områdene kan det være fornuftig å redusere beitetrykket på kort sikt for å øke produksjonen av beite. Det er imidlertid en rekke faktorer som påvirker beiteproduksjonen og som har direkte effekt på tilgangen på vinterbeite for hjorten. Utviklingen i skogbilde og driftsnivå i skogbruket vil skape viktige rammer for beiteproduksjonen, sammen med den aktuelle bestandstettheten av hjort.

Sammendrag

Målet med rapporten er å kunne: " Beskrivelse av bestandsforholdene for hjort med kjønns- og alderssammensetning og antallsmessige bestandsestimat før jakt 2007. " Vise scenarier på hvordan bestandene vil endre seg ved ulike avskytingsmønster framover i tid. " Komme med anbefalinger for framtidig forvaltning av hjort i Eid. Rapporten viser sammenstillinger over ulike typer materiale fra Eid kommune. For modellering av bestand, og som grunnlag for utarbeiding av scenarier, har vi brukt en deterministisk bestandsmodell og definert et utgangspunkt for antall dyr i bestanden fordelt på ulike aldersklasser og kjønn. Tallmaterialet tyder på at hjortebestanden i Eid kommune har vært i vekst fram til om lag 1998. Etter dette har bestanden trolig hatt liten endring antallsmessig. Tallmaterialet ser ut til å indikere en liten økning i andelen bukk i bestanden de senere år, og det ser også ut til at rekrutteringa til bestanden er god, men varierer noe mellom år. Ut i fra de modellforutsetningene beskrevet ovenfor med kun små endringer i bestandsstørrelse i løpet av de siste åra (endringer på 0-1 % årlig) har vi beregna at Eid har en sannsynlig bestandsstørrelse (jaktbestand) 1900 ± 200 dyr før jakt i 2007. Denne bestandsstørrelsen vil kunne være grunnlag for et årlig uttak av 425-485 ± 40 dyr i åra framover avhengig av mål og strategier som blir lagt (se nedenfor). Vi anbefaler kommunen i det videre å gjennomføre slik avskytingsstrategi framover: " Kjønnsnøytral eller liten overvekt av hanndyr dersom man har mål om nullvekst i bestanden. " Kjønnsnøytral eller liten overvekt av hodyr i uttaket dersom man har mål om reduksjon i bestanden. " Kjønnsnøytral eller liten overvekt av hanndyr dersom man har mål om en liten vekst i bestanden. Eid kommune har trolig en bestand før jakt 2007 på 1900 ± 200 dyr, og viser at Eid kommune i 2007 kan felle fra 425-485 ± 40 hjort årlig avhengig av mål for bestandsutvikling framover. Rapporten inneholder i tillegg noen anbefalinger for Eid kommune sin hjorteforvaltning framover.

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Proper management of wildlife relies on metrics of population development. Typically, the best estimation techniques are too expensive for coarse-scale management. In marine fisheries, catch-per-unit effort is commonly used, but problems may arise due to changes in spatial harvest effort or in habitat use as density changes. Managers in Norway are in the early phases of implementing "seen deer" during harvesting and "spring counts" on farmland as a means of monitoring red deer Cervus elaphus populations. We provide a first evaluation of how suitable these methods are by comparing the results with population estimates obtained using cohort analysis, and by analysing the within-season variation in number of seen deer. "Seen deer" predicted annual increases in populations fairly well. Adjusting for harvesting effort provided less good estimates, due to a proportionally larger increase in effort relative to deer population size as population size increased. The number of seen deer per day decreased rapidly at the beginning of the season, and then levelled off or increased slightly during the rut, especially on farmland. The number of seen deer increased both with the number of harvesters and hours harvested, but at a diminishing rate. The current practice of "spring counts" was not successful in predicting population changes, probably due to a lack of replication. Indeed, date strongly affected the number of deer seen during spring counts. While "seen deer" seems to be a very promising tool for monitoring population size of red deer, there are some limitations to the practice as implemented for moose Alces alces in Scandinavia due to a more complex relationship with harvesting effort. Our study highlights that the large number of hours harvesters observe wildlife can provide a useful tool for population monitoring. However, the use of such indices may vary between species and according to harvest techniques and should thus be assessed with care before implementation

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Organic farmers are often advised to plough shallowly (<15 cm) in order to optimise nutrient turnover and to promote the activity of soil biota, but deeper for better control of perennial weeds. Different ploughing depths (13 vs 25 cm) had minor effects on decomposition rate of barley straw and earthworm activity in the decomposing straw when using a light tractor (2 and 4 Mg). However, different burying depths (13 vs 25 cm) of barley straw had some important effects on decomposition and earthworm activity.

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Den store hjortestamma på Vestlandet er ein viktig utmarksressurs som representerer store verdiar for grunneigarar i form av kjøt, jaktutleige og rekreasjon. Samstudes utøvar hjorten skadepress på innmark og skog, noko som gjer at reknestykket vert betydeleg meir komplisert. Resultata så langt syner at hjorten preferer eng med høgt innhald av timotei. Dette er den kvalitativt beste og økonomisk mest verdifulle enga, og hjorten vil ved si beiting endre artsamansettinga i desse engstykka. Dette påfører gardbrukarane ein økonomisk kostnad i form av avlingstap og forringa forkvalitet. Samstundes syner resultata òg at det er svært stor variasjon i skadeomfanget mellom gardbrukarane.