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The management of infectious wildlife diseases often involves tackling pathogens that infect multiple host species. Chronic wasting disease (CWD) is a prion 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 population 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 overlap 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 of spillover to limit adverse impacts and achieve wider societal acceptance is important. [ABSTRACT FROM AUTHOR]

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Although biodiversity is crucial for Sustainable Development Goals (SDGs), following the current trajectory, we risk failing SDG 15. Using a new indicator quantifying the loss of functional habitat (habitat that is simultaneously suitable and well-connected), we show that the real impact of renewable energy is far larger than previously assumed. Specifically, we estimate that the construction of hydropower reservoirs in south Norway caused a loss of ca. 222 km2 of functional habitat for wild reindeer (Rangifer tarandus)—which is far larger than assumed based on land inundation indices (110 km2). Fully mitigating these impacts is challenging: scenario analyses reveal that the measures proposed by societal actors would yield only a fraction of the habitat lost (2–12 km2) and could cause trade-off risks with other SDGs. Using indices of functional connectivity is crucial for environmental impact assessments, as entire ecological networks for several species can be affected far beyond the reservoirs. [ABSTRACT FROM AUTHOR]

Increasingly precise spatial data (e.g. high‐resolution imagery from remote sensing) allow for improved representations of the landscape network for assessing the combined effects of habitat loss and connectivity declines on biodiversity. However, evaluating large landscape networks presents a major computational challenge both in terms of working memory and computation time. We present the ConScape (i.e. "connected landscapes") software library implemented in the high‐performance open‐source Julia language to compute metrics for connected habitat and movement flow on high‐resolution landscapes.The combination of Julia's 'just‐in‐time' compiler, efficient algorithms and 'landmarks' to reduce the computational load allows ConScape to compute landscape ecological metrics—originally developed in metapopulation ecology (such as 'metapopulation capacity' and 'probability of connectivity')—for large landscapes. An additional major innovation in ConScape is the adoption of the randomized shortest paths framework to represent connectivity along the continuum from optimal to random movements, instead of only those extremes.We demonstrate ConScape's potential for using large datasets in sustainable land planning by modelling landscape connectivity based on remote‐sensing data paired with GPS tracking of wild reindeer in Norway. To guide users, we discuss other applications, and provide a series of worked examples to showcase all ConScape's functionalities in Supplementary Material.Built by a team of ecologists, network scientists and software developers, ConScape is able to efficiently compute landscape metrics for high‐resolution landscape representations to leverage the availability of large data for sustainable land use and biodiversity conservation. As a Julia implementation, ConScape combines computational efficiency with a transparent code base, which facilitates continued innovation through contributions from the rapidly growing community of landscape and connectivity modellers using Julia. [ABSTRACT FROM AUTHOR]

In Norway, recovering populations of large carnivores commonly prey on roe deer ( Capreolus capreolus). Understanding predator habitat use and ecology requires fine-scaled information on prey distribution and abundance. However, the massive spatial scales at which large carnivores use the landscape presents many practical and statistical challenges for developing functional prey distribution models. Pellet-count data from > 1000 km of transects gathered across southeastern Norway between 2005 and 2011 were used to derive a map of the relative prey abundance for roe deer. These data were modeled using zero-inflated hurdle models using both environmental and anthropogenic variables. Snow depth and agricultural fields were the most significant variables in explaining both presence and abundance. Internal k-cross validation of the model showed medium accuracy (Spearman's r = 0.35), whereas external evaluation carried out on the basis of independently collected snow-tracking data (Spearman's r = 0.37) and hunting statistics (Spearman's r = 0.88) showed higher accuracy. The map generated can facilitate both the study of broad scale processes linking predators and prey as well as roe deer management in southeastern Norway. [ABSTRACT FROM AUTHOR]

Norwegian wild reindeer Rangifer tarandus tarandus are divided into 23 virtually isolated populations, primarily due to the abandonment of traditional migration and movement corridors caused by the development of infrastructures. By conducting a nation-wide, interdisciplinary pre-post study on a temporal scale spanning centuries, we modelled current reindeer movements with respect to archaeological findings to quantify long-term changes in area use related to anthropogenic disturbance. The location of 3,113 pitfall traps and hunting blinds, built 600-2000 years ago and used until 350-400 years ago, testified the location of traditional movement corridors. Current movement routes were delineated using Brownian Bridge Movement Models based on 147 reindeer GPS-monitored during 10 years. Using Path Analysis we quantified direct, indirect and total effects of different infrastructures within multiple scales (1, 5, and 10 km-radius buffers) on the current probability of use of ancient movement corridors. Tourist cabins and roads had the strongest long-term direct effects at most scales: 1 tourist cabin and 1 km road within a 1 km-radius buffer would lead, respectively, to complete area abandonment, and to a 46 % decrease in the probability of use. Power lines and private cabins had significant indirect effects on area use through their effect on roads, while hiking trails and, in particular, hydroelectric dams had highly variable effects, not significant at a nation-wide scale. Finally, we provide a flexible tool to estimate the potential long-term direct and cumulative effects of different types of infrastructures at the desired spatial scale to be used for the development of future sustainable land management plans. [ABSTRACT FROM AUTHOR]

The development of roads and associated infrastructure has interrupted several traditional migrations of wild reindeer (Rangifer tarandus tarandus) in Norway. The population in the Setesdal Austhei wild reindeer area still migrates from winter to calving grounds by semi-annually crossing a cabin-lined road through a narrow corridor, in which further anthropogenic development is planned. To understand if and how infrastructure affected reindeer migration patterns we studied the movements of 10 female reindeer equipped with GPS collars between 2002 and 2010. First, we identified the start and end of the migration period, and then we compared trajectory parameters (net displacement, step length and turning angles) recorded during migration with those recorded in proximity of the road. The analysis of the net displacement indicated that during spring migration reindeer moved at a constant pace towards the calving ground covering a net linear distance of 25 km in 40 days. In the middle of migration, reindeer changed travel direction and roamed parallel to the road for ca. 5 days without approaching further, possibly searching for an undisturbed place and time to cross. Reindeer finally crossed the road before daylight with highly directed movements, increasing their travel speed up to the highest values recorded during migration (4 km/3 hrs vs. 0.5 km/3 hrs). After crossing, reindeer moved quickly toward their calving ground covering the remaining 25 km net distance in less than a week. Migration patterns were markedly affected by disturbance during spring, as the road crossings occurred in the period characterized by the high traffic volume and intense human activities related to Easter holidays; during autumn, on the contrary, the hampering effect of the road was minimal. The results suggest that the current disturbance associated to the road hampers spring migration and might delay the arrival to the calving ground. The planned construction of a large number of recreational cabins in the migration corridor has the potential to threaten the migration and obstruct the access to the calving ground. [ABSTRACT FROM AUTHOR]

The negative impact of anthropogenic disturbance and land-use changes on large mammals is generally recognized within conservation biology. In southeastern Norway, both moose ( Alces alces) and roe deer ( Capreolus capreolus) occur throughout human-modified landscapes, facilitating an interesting comparative study of their habitat use. By using pellet group counts, we looked at the importance of forest structure, vegetation characteristics and human disturbance (e.g., distance to the nearest house, nearest paved road, and nearest edge between field and forest) in shaping the winter distribution of both species at multiple spatial scales, in non-agricultural habitats. Moose occurred more often in areas with higher densities of heather and Vaccinium sp. in the ground layer, and used areas with more open forest structure. The proportion of built-up areas, within a 1,000-m buffer, negatively influenced moose occurrence. Roe deer occurred more often in areas with deciduous trees and patches with juniper and Vaccinium sp. in the ground layer, used areas near roads less, but were significantly associated with areas near the field-forest ecotone. The proportion of built-up areas positively influenced roe deer distribution within a 2,500-m buffer. Roe deer seem to be able to persist in more human-dominated landscapes, possibly due to the availability of field-forest edges providing both high-quality fodder and cover in close proximity. Moose, on the contrary, did not show any preference for areas associated with human disturbance, and their distribution was only associated with patches providing food. [ABSTRACT FROM AUTHOR]

The choice of neonatal hiding place is critical for ungulates adopting hiding anti-predator strategies, but the consequences of different decisions have rarely been evaluated with respect to offspring survival. First, we investigated how landscape-scale choices made by roe deer fawns and their mothers affected predation risk by red foxes in a forest–farmland mosaic in southeastern Norway. After, we examined the effect of site-specific characteristics and behaviour (i.e. visibility, mother–fawn distance and abundance of the predator’s main prey item—small rodents) on predation risk. The study of habitat use, selection and habitat-specific mortality revealed that roe deer utilised the landscape matrix in a functional way, with different habitats used for feeding, providing maternal care and as refugia from predation. Mothers faced a trade-off between foraging and offspring survival. At the landscape-scale decisions were primarily determined by maternal energetic constraints and only secondarily by risk avoidance. Indeed, forage-rich habitats were strongly selected notwithstanding the exceptionally high densities of rodents which increased fawn predation. At fine spatial scales, a high visibility of the mother was the major factor determining predation risk; however, mothers adjusted their behaviour to the level of risk at the bed site to minimise predation. Fawns selected both landscape-scale refugia and concealed bed sites, but failure to segregate from the main prey of red foxes led to higher predation. This study provides evidence for the occurrence of spatial heterogeneity in predation risk and shows that energetically stressed individuals can tackle the foraging-safety trade-off by adopting scale-dependent anti-predator responses. [ABSTRACT FROM AUTHOR]

Abstract: During the last century the boreal forests of south-eastern Norway have been converted into patchworks of agricultural areas, clear-cuts and even-aged conifer monocultures. Even though Scandinavian forest ecosystems are strongly influenced by small mammals’ dynamics, the effects of anthropogenic changes on these communities are still debated. We conducted an extensive capture–mark–recapture study to examine the relative abundance and distribution of 11 species of small mammals during the reproductive season with respect to all available landscape-scale habitat types and fine-scale vegetation characteristics. At the landscape scale, the highest abundance and diversity of small mammals was recorded in abandoned meadows. The community was dominated by Myodes glareolus in old abandoned meadows sparsely colonized by trees and bushes, and by Microtus agrestis in younger grass-dominated meadows, likely reflecting inter-specific competition and niche separation. Notwithstanding the remarkably low availability of both types of meadows, these habitats sustained by far the highest abundance of small mammals. Intensively managed forest monocultures at logging age and cultivated fields sustained the lowest abundance of small mammals. However, while the former also supported the lowest species diversity, the latter unexpectedly sustained the highest number of species. Only Apodemus sylvaticus attained highest densities in cultivated fields, but its marked association with forest edges clearly indicates its need for landscape-scale complexity. Contrary to previous theories, clear-cuts and forests overall did not support the highest abundance of M. agrestis and M. glareolus. Both young and mature forests failed to explain a significant amount of variation in community structure when taking into account other habitat types. However, a few old clear-cuts characterized by higher vegetational complexity, and a few stands preserving characteristics typical of late successional stages (moss, berries, woody debris) were able to support relatively high abundance of small mammals. Our study shows that sampling in all available habitats at different spatial scales is essential for a comprehensive understanding of community dynamics in forest–farmland ecosystems, as even habitat types that are under-represented at the landscape scale might play a significant role for the community dynamics. Forest–farmland mosaic landscapes with a high degree of heterogeneity at both large spatial scale (e.g. meadows, shelterbelts) and at fine-scales (e.g. varied and multi-layered ground cover) allow for the conservation of small mammal diversity and abundance in human-dominated areas. Nonetheless, the low number of Myodes rufocanus trapped in this highly fragmented mosaic landscape supports the hypothesis that habitat fragmentation negatively affects the dynamic of this forest specialist. [Copyright &y& Elsevier]

Red fox Vulpes vulpes predation on roe deer Capreolus capreolus fawns has the potential to strongly affect prey population dynamics, but it is unclear whether this relationship is symmetrical or not. We analysed the spring–summer diet of adult foxes and of their cubs in a fragmented agricultural area of southeastern Norway, where a parallel study showed that the predator kills annually 25% of the radio-monitored roe deer fawns. The overall diet was highly varied and was dominated by small mammals (33% volume), especially Microtus agrestis, and medium-large mammals (25%), largely represented by fawns. The frequency of occurrence (FO) of fawns in the diet of adult foxes was highest in early spring, thus, supporting previous studies showing that the predator started actively hunting for fawns from the very beginning of the birth season. During the summer, the FO of both fawns and small mammals markedly declined, while that of berries and invertebrates increased. As expected for central-place foragers, cubs consumed a higher proportion of large prey items compared to adults. In particular, 25% of scats from cubs—versus 9% from adults—contained roe deer remains, suggesting a high profitability of fawns for vixens raising offspring. However, considering the wide food spectrum and the availability of several large prey items in our study area, it seems unlikely that the importance of fawns to the diet and population dynamics of red foxes could be as great as the impact of the predator on roe deer populations. This asymmetrical relationship implies that there are unlikely to be any stabilising feedback mechanisms in the predator–prey relationship. [ABSTRACT FROM AUTHOR]

Abstract: In the face of climate change and habitat fragmentation there is an increasingly urgent need to learn more about factors that influence species distribution patterns and levels of environmental tolerance. Particular insights can be obtained by looking at the edges of a species range, especially from species with wide distributions. The European roe deer was chosen as a model species due to its widespread distribution. By using pellet group counts, we studied summer and winter habitat use of this herbivore at two of the extreme edges of its distribution – southwest of Portugal, and northeast of Norway – in relation to a range of fine-scale environmental factors including forest structure, vegetation characteristics and human disturbance. Our first prediction that roe deer would respond differently to human activity in both counties was supported. While in Norway roe deer are always close to houses, in Portugal they are either far (in summer) or indifferent (winter). However, everywhere and in every season, roe deer are far from roads. Our second prediction that roe deer better tolerate anthropogenic disturbances in the area where the importance of limiting factors is higher (Norway) was validated. However, our third prediction that anthropogenic disturbance would be less tolerated by roe deer outside the limiting seasons in each country was not supported. Our results suggest that roe deer perceive human activities differently in the two countries and that roe deer better tolerate anthropogenic disturbances in Norway. [Copyright &y& Elsevier]