ABSTRACT Roe deer and mountain hares are known to select the same food sources and engage in indirect exploitative competition. Here we report on a case of direct interaction between a roe deer doe and a mountain hare recorded by a camera trap in Tydal Municipality, Norway, a possible case of direct interference competition. The roe deer doe is at least following and displacing the mountain hare for 2 min and 29 s, including a 19 s active chase phase. The two animals can be seen circling in and out of frame in front of the camera. This direct interaction is based on the limited information gained through the picture series. It could be a case of curiosity; however, we speculate that this is a case of interference encounter competition between these two herbivore species. From the literature, roe deer and mountain hares are known to compete indirectly for forage; moreover, roe deer are known to behave aggressively towards other competing deer species. Our traditional textbook understanding of ecology is based on the common and the easily observable, not the rare and difficult to observe. This observation challenges our understanding of the interactions between roe deer and hares, as roe deer may compete directly with mountain hares over food resources.

Climate change has reduced the duration of seasonal snow cover in many areas, leading to seasonal coat colour-changing species being colour mismatched against their environment for increasingly long periods. This mismatch in camouflage can lead to increased predation, potentially resulting in population-level effects. Here we investigate how mountain hare (Lepus timidus) camouflage is influenced by climate change-induced reductions in snow cover over a 60-year period. We quantified the degree of camouflage mismatch using multiannual (2011-2018) camera trap data from 678 camera traps spread across an environmental gradient in Norway spanning from 58° N to 69° N, and from coastal to inland areas. We coupled this camouflage data with a 60-year snow cover time series on a national scale, creating two 30-year averages of snow cover duration (1959-1988 and 1989-2018). We investigated how climate change-induced reductions in snow cover correlate with coat colour camouflage and resulting mismatch. Specifically, we analysed how mountain hare coat colour mismatch varied between camera trap locations with varying reductions in the number of snow days between the two 30-year averages. We also investigated how 2011-2018 mountain hare moult phenology compared to 1959-1966 and 2011-2018 average snow cover, respectively. Coat colour mismatch was highest in areas with the greatest reductions in the number of snow days. Additionally, 2011-2018 moult phenology better matched 1959-1966 than 2011-2018 snow patterns. Collectively, our results indicate that mountain hares are not adjusting their moult phenology fast enough to track the pace at which snow cover is declining.

Roe deer is a species that hides their neonates as an anti-predator strategy. This may prove efficient against mammalian predators, such as the red fox; however, it might be an ecological trap as large numbers of fawns are killed by tractors with harvesters each year during grass harvest. Here, we evaluate a low-tech, low-cost method, using scaring flags placed in the field the evening before grass harvest, intended to stimulate the roe deer doe to remove any fawns from the field. We evaluate the effects of the scaring flags by counting the number of fawns in the fields using a multi-rotor drone equipped with a thermal camera. The drone proved to be an efficient tool for detecting roe deer fawns. However, contrary to other studies, we found limited or no effect of placing the scaring flags in the field. This discrepancy highlights the fallacy of generalizing based on single case studies. There is still a need to develop low-cost, easily applicable tools to reduce roe deer fawn mortality during grass harvest. However, with the increasing technological development, drones with thermal cameras are a promising tool for wildlife management and monitoring in the future.

The direct effects of hunting on hunted individuals and populations have been well known for a long time. However, recently there has also been an increased focus on the indirect, non-lethal effects of hunting. When approached by a possible threat such as a predator, the prey releases various stress hormones into the bloodstream. Cortisol is one of these hormones and the blood concentration is an indicator of stress levels in mammals. Here we report on a study on the effects of using hunting dogs versus walk-up shooting on mountain hare blood cortisol levels. We sampled 20 hares hunted using dogs and 32 control hares hunted without using dogs. On average the cortisol level in hares hunted using dogs was 44.6 ng/ml, while in hares harvested without being chased by dogs it was 6.8 ng/ml. Based on the blood hormone levels of this study we cannot conclude if the elevated cortisol levels we see in the hares hunted using dogs was harmful to the hares had they not been shot. However, given what is known about the effects of chronic stress, we would caution against repeated chases of individual hares. The cumulative effect of stressors including hunting is likely crucial for any effects on reproduction and survival. Thus, there is a need to evaluate the long-term effects of hunting chases and other human activities on mountain hare stress hormone levels, and to investigate the long-term effect on hare behavior, space use, survival, reproduction and recruitment.

Climate change has resulted in a myriad of stressors to wild organisms. Phenotypic plasticity, including behavioral plasticity, is hypothesized to play a key role in allowing animals to cope with rapid climate change and mitigate its negative fitness consequences. Camouflage mismatch resulting from decreasing duration of snow cover presents a stressor to species that undergo coat color molts to maintain camouflage against seasonally changing backgrounds. Winter white animals appear highly conspicuous against dark, snowless background and experience increased predation‐induced mortality. Here, we evaluate the potential of behavioral plasticity to buffer against camouflage mismatch in mountain hares Lepus timidus in Scotland. We carried out field surveys in three populations over two years and found no evidence that hares modify their behaviors in response to increasing camouflage mismatch. Hares did not prefer to rest closer to light‐colored rocks or farther from conspecifics with increasing color contrast. Furthermore, whiter hares did not seek to rest closer to snowy backgrounds; rather, hares preferred to sit farther from snow. These results suggest that behavioral plasticity might not be a universal, rapid mechanism facilitating adaptation to climate change. Keywords: behavioral plasticity, camouflage, climate change, mountain hares, phenological mismatch

Northern small mammal populations are renowned for their multi-annual population cycles. Population cycles are multi-faceted and have extensive impacts on the rest of the ecosystem. In 2011, we started a student-based research activity to monitor the variation of small rodent density along an elevation gradient following the Birkebeiner Road, in southeast Norway. Fieldwork was conducted by staff and students at the University campus Evenstad, Inland Norway University of Applied Sciences, which has a long history of researching cyclic population dynamics. The faculty has a strong focus on engaging students in all parts of the research activities, including data collection. Small rodents were monitored using a set of snap trap stations. Trapped animals were measured (e.g. body mass, body length, sex) and dissected to assess their reproductive status. We also characterised the vegetation at trapping sites. We provide a dataset of small rodent observations that show fluctuating population dynamics across an elevation gradient (300 m to 1,100 m a.s.l) and in contrasting habitats. This dataset encompasses three peaks of the typical 3-4-year vole population cycles; the number of small rodents and shrews captured show synchrony and peaked in years 2014, 2017 and 2021. The bank vole Myodes glareolus was by far (87%) the most common species trapped, but also other species were observed (including shrews). We provide digital data collection forms and highlight the importance of long-term data collection.

AbstractLocal adaptation to annually changing environments has evolved in numerous species. Seasonal coat colour change is an adaptation that has evolved in multiple mammal and bird species occupying areas that experience seasonal snow cover. It has a critical impact on fitness as predation risk may increase when an individual is mismatched against its habitat's background colour. In this paper, we investigate the correlation between landscape covariates and moult timing in a native winter‐adapted herbivore, the mountain hare (Lepus timidus), throughout Norway. Data was collected between 2011 and 2019 at 678 camera trap locations deployed across an environmental gradient. Based on this data, we created a Bayesian multinomial logistic regression model that quantified the correlations between landscape covariates and coat colour phenology and analysed among season and year moult timing variation. Our results demonstrate that mountain hare moult timing is strongly correlated with altitude and latitude with hares that live at higher latitudes and altitudes keeping their winter white coats for longer than their conspecifics that inhabit lower latitudes and altitudes. Moult timing was also weakly correlated with climate zone with hares that live in coastal climates keeping their winter white coats for longer than hares that live in continental climates. We found evidence of some among year moult timing variation in spring, but not in autumn. We conclude that mountain hare moult timing has adapted to local environmental conditions throughout Norway.

Mountain hares (Lepus timidus) in Scandinavia are classified as Near Threatened in the Norwegian and Swedish Redlists. This is due to a possible population decline witnessed during the last decades in Scandinavia. Competition between large herbivores and mountain hares is one of several hypotheses that has been put forward to explain this decline. In a cafeteria trial we investigate the effects of previous moose (Alces alces) winter browsing on the food selection (i.e., biomass consumed, bites per minute and bitediameter) of downy birch (Betula pubescens) and goat willow (Salix caprea) by captive mountain hares. We find that mountain hares do not differentiate among previous browsing levels of downy birch, but have larger bite diameters of goat willow earlier browsed by moose, compared to non-browsed plants. Thus, effects of moose on mountain hare winter food quality seem to be limited. We highlight the need for studies focusing on (1) qualitative effects of moose browsing using wild mountain hares in a natural experimental design, and (2) quantitative effects of moose browsing on available mountain hare forage at a landscape scale during winter.

There are two main international strategies concerning how to ensure a sustainable environment: one is to develop a globally bio-based economy, or bioeconomy, to meet the increased demand of goods and products to maintain our well-being and to reduce climate change. On the other hand, there is an aim to decrease the negative impacts on nature and natural habitats to conserve and maintain ecosystems and control the loss of biodiversity. There is a trade-off between these two strategies; as we increase the commitment to the bioeconomy by intensifying biomass production, we will simultaneously challenge biodiversity through the increased pressure on, and the utilization of, biological raw materials. Here, we first review and discuss the challenges and opportunities in terrestrial and marine ecosystems for the production of biomass for the bioeconomy. We focus on the trade-offs between economic sustainability on one hand, and environmental sustainability and resilience on the other hand. We conclude with a discussion of the various bioeconomy strategies. Finally, we present a conceptual model on how to sustainably develop the bioeconomies (by introducing the concept of optimizing the economic gain/ecological pain ratio) to be able to manage the biodiversity in a sustainable way.

Centralized management of large carnivore populations in rural and remote landscapes used by local people often leads to conflicts between the objectives of wildlife conservation and rural development. We tested the hypothesis that the presence of wolves indirectly reduces landowner revenues from traditional small game hunting, and that landowner revenues are more variable closer to wolf territories. The assumed mechanism is that hunters fear that their economically and culturally valuable hunting dogs may be killed by wolves, which results in reduced hunting, and thus reduced revenues for landowners where and when wolves occur. To determine the effect of wolf presence on revenues from sport hunting, we obtained data from 1990 to 2009 on income from small game management areas, in Hedmark and Oppland Counties in Norway, as well as locations of wolf territories. Small game management areas experienced increased sport hunting revenue with increasing distance to the closest wolf territory. Also, inter-annual variation in revenue decreased with increasing distance from wolf territories. Thus, wolf presence may reduce landowners' revenues from small game hunting, and cause higher economic variability in rural communities. It is important to note that while the economic impacts of wolves may be compensated where governments have the will and the economic resources, the impacts on the lifestyles of rural people (e.g. hunter's fear of losing prized dogs to wolves) will remain controversial.

Browsing can reduce forest productivity, particularly when the apical shoots of trees are damaged. Repellents are used widely to reduce browsing, but application is costly. To improve efficiency, it may be possible to take advantage of associational plant refuge effects, requiring repellents to be applied only to some trees or parts of trees, or reapplied less frequently. Using captive moose ( Alces alces ) and constructed stands of Scots pine ( Pinus sylvestris ), we tested for potential refuges by applying a commercial repellent (HaTe2) to all, alternate or none of the apical shoots, or all of the previous-year apical shoots. We also tested for potential refuges under field conditions, applying the repellent to all, alternate or none of the apical pine shoots in forest stands. Captive moose (two individuals in a 2.1-ha enclosure, ~ 95 individuals km −2 ) browsed 100% of trees, but were significantly less likely to browse apical shoots treated with repellent. Associational refuge was ineffective both within and between trees. In the field (0.84 moose km −2 ), only 1.3% of trees sustained browsing damage. Applying the repellent to the apical shoots of pines had no direct repellent effect nor any within-plant associational effects. Trees with treated apical shoots provided some protection for untreated neighbouring trees, but this was not biologically meaningful given the low percentage of trees browsed overall. Here, a simple captive experiment was not predictive of the browsing response observed in the field, demonstrating the need to test repellent application strategies in situ.

To support human well-being, green (or ecological) infrastructure policy stresses the need to sustain functional networks of representative terrestrial and aquatic ecosystems for the sustainable provision of multiple ecosystem services. Implementing this means that the complexity of interactions between social and ecological systems at multiple spatial scales and levels of governance needs to be understood. Place-based knowledge production and learning through integration of different research disciplines in collaboration with actors and stakeholders (i.e. transdisciplinary research) is a key feature to achieve this goal. Using a suite of local landscapes and regions on the European continent's West and East as a laboratory, we developed and applied a step-wise approach to produce knowledge and encourage learning towards functional green infrastructures. Our diagnoses of forest landscapes show that the functionality for wood production and biodiversity conservation was inversely related in the gradient from long to short forest management histories. In Europe's West there is a need for increased quantity of, and more functional, protected areas; diversification of management methods; and landscape restoration. In NW Russia there are opportunities to intensify forest management, and to continue the land-sparing approach with zoning for different functions, thus reducing biodiversity loss. Examples of diagnoses of social systems included the evaluation of comprehensive planning in Sweden, outcomes for biodiversity conservation of forest certification in Lithuania, and learning from environmental managers. We conclude that the main challenge for securing functional green infrastructure is poor cross-sectoral integration. Treatment of social-ecological systems requires knowledge-based collaboration and learning. The diversity of landscape histories and governance legacies on the European continent's West and East, including Russia, offers grand opportunities for both knowledge production about performance targets for green infrastructure functionality, as well as learning to adapt governance and management to regional contexts. Integrating project funding for both researchers and stakeholder collaboration is a necessary strategy to fill the transdisciplinary research agenda. However, formal and informal disciplinary and administrative barriers can limit team building despite self-reflection and experience.

How to manage the impact of a large moose population on the economically important Scots pine, and on ecologically important mature aspen, rowan and willow trees as habitat for lichen, moss, insect and bird species, are hot topics in Fennoscandia for forest and wildlife managers. To understand if the study design affects conclusions about the impact of moose browsing damage on young trees of economic and ecological importance we used three macroecological approaches: (1) a comparison of Swedish forest landscapes managed for intensive coniferous wood production, (2) a natural experiment approach that compared forests with different abundance of moose in Sweden, and (3) a comparison of browsing damage across six countries in northern Europe from Norway in the west to Russia in the east. The results show that Sweden had high moose densities across all landscapes studied, high overall rates of browsing damage, and therefore a weak relationship between moose density and browsing damages. A comparison between managed forest landscapes and urban forest areas, which are less accessible to moose, showed a clear effect of moose density on tree damage of both economically and ecologically important tree species. Finally, across 10 landscapes in Sweden, Norway, Finland, Latvia, Belarus and Russia we found that moose had a strong effect on damage to both groups of tree species. Research design affects the conclusions about the role of moose density for browsing damage on economically and ecologically valuable tree species. Macroecological studies in landscapes, representing different contexts on the European continent's West and East, form a valuable approach to produce new knowledge. We discuss the need for integration of the management of moose and their predators (including man) as well as forest management and biodiversity conservation planning.

To investigate if the study design affects conclusions about the impact of moose browsing damage on young trees we used three designs: (1) a comparison of managed Swedish forest landscapes, (2) a natural experiment approach in Sweden, and (3) a macroecological approach involving six countries in northern Europe from Norway to Russia. Per Angelstam, Simen Pedersen, Michael Manton, and Marine Elbakidze

Loss of large carnivore populations may lead to increased population densities of large herbivores, and subsequent cascading effects on the composition, structure, and function of ecosystems. Using a macroecological approach based on studies in multiple boreal forest landscapes in the Baltic Sea region and Russia, we tested the hypothesis that disrupted trophic interactions among large carnivores and large herbivores affect the recruitment of both ecologically and economically valuable tree species. We measured damage levels on young trees and large herbivore density in 10 local landscapes representing a gradient from extinct to extant populations of both large carnivores and large herbivores. We also tested the alternative hypothesis that forest management intensity is correlated to reduced recruitment of these tree species. At the macroecological scale there was an inverse relationship between the number of large carnivores and large herbivores. This coincided with a steep gradient in browsing damage on the ecologically important aspen, rowan and sallow as hosts for specialized species, as well as the economically important Scots pine. In one landscape hunting had replaced the presence of carnivores. Mean damage levels of these four tree species were correlated with large herbivore abundance, but not with forest management intensity. We discuss the pros and cons of this macroecological approach, as well as the challenge of governing and managing trophic interactions at multiple scales.

Due to anthropogenic alteration of stand composition and landscape pattern in Swedish forest landscapes managed for industrial wood production, remnant patches of deciduous forests and woodlands do not form a functional green infrastructure for biodiversity conservation. We assessed if large herbivore browsing hampers the restoration of deciduous forest as green infrastructure by reducing the recruitment of boreal and temperate deciduous tree species of particular importance for biodiversity conservation. A natural experiment approach was applied in the distinct Swedish temperate-boreal forest gradient in Sweden. We measured the potential for saplings of aspen, rowan, sallow and oak to become recruited into the population of ecologically mature trees, as well as the amount of tree and field layer food. Sampling was made in forest stands representing four strata of managed forest landscapes accessible to large herbivores (experiment) and human settlements avoided by large herbivores (control). All four focal deciduous tree species had lower damage levels in controls (towns and villages) compared to experimental (forest) sites. While tree forage was much more abundant in controls, field layer forage in controls was not different from experimental stands. For all tree species except aspen we found a positive relationship between damage levels and large herbivore abundance, to which moose contributed >89%. We discuss the role of research design for assessing the impact of large herbivores on plants, and highlight the need for integration of multi-species wildlife management as well as conservation planning and management.

In northern latitudes, species that have adapted to snow cover by molting and changing pelage color will be particularly vulnerable to climate change, as predation levels may increase due to a mismatch with background coloration. Here, we investigated the synergistic effect of mammalian generalist predators (red fox Vulpes vulpes and pine marten Martes martes) and the duration of snow cover on the abundance of a winter-adapted species, the mountain hare (Lepus timidus). We analyzed 12 yr of data from 622 snow tracking lines in southeast Norway along a gradient in annual duration of snow-covered ground. The mountain hare abundance index was positively related to the generalist predator abundance index, probably due to a combined numerical and functional response of the predators. The mountain hare abundance index was negatively associated with a short duration of snow cover, and this effect was stronger in areas with a high predator abundance index. Hence, we demonstrated a causal link between the mountain hare abundance index, predators, and the duration of snow cover. We expect declining mountain hare densities in the future caused by interactive effects of reduced duration of snow-covered ground, potentially increasing generalist predator densities and the limited ability of mountain hares to adapt to the climate change-induced molting mismatch.