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Significance We are experiencing the accelerated loss and reconfiguration of biological diversity. Meanwhile, those charged with natural resource management are struggling to meet the challenges of monitoring and managing wildlife populations across vast areas crisscrossed by political borders. What if, akin to weather maps, we could track and forecast the dynamics of wildlife populations across space and time? Using the world’s most extensive large carnivore monitoring program, we showcase the application of an effective tool for spatially explicit quantification of wildlife population dynamics at scales that are relevant to management and conservation., The ongoing recovery of terrestrial large carnivores in North America and Europe is accompanied by intense controversy. On the one hand, reestablishment of large carnivores entails a recovery of their most important ecological role, predation. On the other hand, societies are struggling to relearn how to live with apex predators that kill livestock, compete for game species, and occasionally injure or kill people. Those responsible for managing these species and mitigating conflict often lack fundamental information due to a long-standing challenge in ecology: How do we draw robust population-level inferences for elusive animals spread over immense areas? Here we showcase the application of an effective tool for spatially explicit tracking and forecasting of wildlife population dynamics at scales that are relevant to management and conservation. We analyzed the world’s largest dataset on carnivores comprising more than 35,000 noninvasively obtained DNA samples from over 6,000 individual brown bears (Ursus arctos), gray wolves (Canis lupus), and wolverines (Gulo gulo). Our analyses took into account that not all individuals are detected and, even if detected, their fates are not always known. We show unequivocal quantitative evidence of large carnivore recovery in northern Europe, juxtaposed with the finding that humans are the single-most important factor driving the dynamics of these apex predators. We present maps and forecasts of the spatiotemporal dynamics of large carnivore populations, transcending national boundaries and management regimes.

The effects of human disturbance spread over virtually all ecosystems and ecological communities on Earth. In this review, we focus on the effects of human disturbance on terrestrial apex predators. We summarize their ecological role in nature and how they respond to different sources of human disturbance. Apex predators control their prey and smaller predators numerically and via behavioral changes to avoid predation risk, which in turn can affect lower trophic levels. Crucially, reducing population numbers and triggering behavioral responses are also the effects that human disturbance causes to apex predators, which may in turn influence their ecological role. Some populations continue to be at the brink of extinction, but others are partially recovering former ranges, via natural recolonization and through reintroductions. Carnivore recovery is both good news for conservation and a challenge for management, particularly when recovery occurs in humandominated landscapes. Therefore, we conclude by discussing several management considerations that, adapted to local contexts, may favor the recovery of apex predator populations and their ecological functions in nature. carnivore recovery; ecological function; human disturbance; human-dominated landscapes; large carnivores; Northern hemisphere

Exposure to lead (Pb) is a global health problem for both humans and wildlife. Despite a dramatic decline in human Pb exposure following restrictions of leaded gasoline and industry and thereby an overall reduction of Pb entering the environment, Pb exposure continues to be a problem for wildlife species. Literature on scavenging terrestrial mammals, including interactions between Pb exposure and life history, is however limited. We quantified Pb concentration in 153 blood samples from 110 free-ranging Scandinavian brown bears (Ursus arctos), 1–25 years old, using inductively coupled plasma sector field mass spectrometry. We used generalized linear models to test effects of age, body mass, reproduction status and spatial distribution on the blood Pb concentrations of 56 female bears. We sampled 28 females together with 56 dependent cubs and paired their blood Pb concentrations. From 20 lactating females, we measured the Pb concentration in milk. The mean blood Pb concentration was 96.6 μg/L (range: 38.7.0–220.5 μg/L). Both the mean and range are well above established threshold concentrations for developmental neurotoxicity (12 μg/L), increased systolic blood pressure (36 μg/L) and prevalence of kidney disease in humans (15 μg/L). Lactating females had higher Pb blood concentrations compared to younger, non-lactating females. Blood Pb concentrations of dependent cubs were correlated with their mother's blood Pb concentration, which in turn was correlated with the Pb concentration in the milk. Life-long Pb exposure in Scandinavian brown bears may have adverse effects both on individual and population levels. The high blood Pb concentrations found in brown bears contrast the general reduction in environmental Pb contamination over the past decades in Scandinavia and more research is needed to identify the sources and pathways of Pb exposure in the brown bears. Lead, Blood, Milk, Ursus arctos, Carnivora

Knowledge about the connectivity among natural populations is essential to identify management units for effective conservation actions. Conservation-minded management has led to the recovery of large carnivore populations in northern Europe, possibly restoring connectivity between the two separated, but expanding brown bear (Ursus arctos) populations on the Scandinavian peninsula to the west and Karelia, a part of the large Eurasian population, to the east. The degree of connectivity between these populations has been poorly understood, therefore we investigated the extent of connectivity between the two populations using autosomal microsatellites and Y chromosome haplotypes in 924 male bears (the dispersing sex), sampled during a period of 12 years (2005–2017) across the transborder area where these two populations meet. Our results showed that the two populations are not genetically isolated as reported in earlier studies. We detected recent asymmetrical gene flow at a rate (individuals per generation) of 4.6–5.5 (1%) from Karelia into Scandinavia, whereas the rate was approximately 27.1–34.5 (8%) in the opposite direction. We estimated historical gene flow of effective number of migrants to be between 1.7 and 2.5 between the populations. Analyses of Y chromosome markers supported these results. Successful recovery and expansion of both populations led to the restoration of connectivity, however, it is asymmetric, possibly due to different recovery histories and population densities. By aligning monitoring between neighboring countries, we were able to better understand the biological processes across the relevant spatial scale. Brown bear Genetic structure Male gene flow Microsatellites Migration Recovery Ursus arctos Wildlife monitoring Y chromosome

Large carnivores play a key ecological role in nature, yet quantifying the effects of predation at large spatiotemporal scales remains challenging. Wolves and brown bears have recovered in Sweden, where they share the same staple prey, moose. This ecosystem is representative of the Eurasian boreal realm, and makes an interesting case study for exploring the use of hunter-collected observation data to understand the ecological effects of large carnivore recovery in human-dominated ecosystems. We used over 50 million hours of moose ob-servation data collected by “citizen scientists” (i.e., moose hunters) between 2000 and 2017 to evaluate the role of recovering bear and wolf populations on an important ungulate vital rate, calf/cow ratio (the number of observed calves per female in fall). Calf/cow ratios were negatively correlated with both wolf and bear densities, suggesting that summer calf survival decreased via predation. Calf/cow ratios decreased by 7% and 17% in the northern and southern areas where bears and wolves were allopatric, respectively. Where wolves and bears were sympatric, the effect of predator densities was additive; calf/cow ratios decreased by 18%. However, both calf/cow ratios and moose densities declined over the last ~20 years across Sweden, including areas where wolves and bears were absent. While recolonizing large carnivores affected ungulate vital rates in Sweden’s human-dominated landscape, they were likely not the primary driver of long-term moose population trends. Our results re-inforce that citizen-collected data are a useful wildlife monitoring tool that help understand ecological processes, including the effects of recovering carnivores on prey populations. Brown bear Calf/cow ratio Carnivore recovery Predator-prey interactions Wolf

Brown hare (Lepus europaeus) seems to outcompete mountain hare (L. timidus) wherever the two species co-occur, but few studies have validated or even addressed this issue. In southern Sweden, the distribution of non-native brown hare overlaps with that of the mountain hare subspecies heath hare (L. t. sylvaticus), possibly the only mammalian subspecies unique to Sweden. In any competitive interaction, at least one species is negatively affected. If outcompetition occurs, then population trends over geographical areas where both species occur should be correlated. In order to assess this, we analysed Swedish hunting harvest data on brown hare and mountain hare for correlations on different spatial scales. We also assessed the relative importance of red fox (Vulpes vulpes) for hare populations by incorporating hunting harvest data for red fox in the analysis. A decline in hunting harvest was observed for both hare species throughout Sweden, while harvest of foxes increased. The harvest decline in mountain hare was generally larger than that in brown hare, particularly in the southern half of Sweden where heath hare is the dominant mountain hare subspecies. Observed patterns in the hunting harvest data for southern Sweden indicate an alarming declining trend for heath hare subspecies, with an obvious risk of extinction. In combination with continued research efforts, we suggest an adaptive management programme to preserve and restore the heath hare subspecies in its current range, through a network of ‘reservoir islands’ with supplementary translocation of heath hare. Developing and implementing an educational public outreach programme aimed at local hunting and naturalist associations can also help facilitate heath hare conservation. Hunting harvest data Alternative stable state Hare Lepus Interaction Competition Predation

Human disturbance causes behavioral responses in wildlife, including large carnivores. Previous research in Scandinavia has documented that brown bears (Ursus arctos) show a variety of behavioral reactions to different human activities. We investigated how proximity to human settlements and roads, as proxies of human influence, affected brown bears' reactions to encountering humans. We analyzed experimental approaches to GPS collared bears, 18 males and 23 single females, in Sweden (n = 148 approaches) and Finland (n = 33), conducted between 2004 and 2012. The bears in Finland inhabited areas with higher human density compared to Sweden. However, the proportion of bears staying or moving when approached and the flight initiation distances were similar in both countries. In Sweden, the flight responses were not dependent on human densities or roads inside the bears' home ranges or the distances from the bears to roads and settlements. Brown bears in Fennoscandia live in areas with relatively low human population densities, but in many areas with high forestry road densities. Our results show that bears' flight reactions were consistent between areas, which is an important message for management, reinforcing previous studies that have documented human avoidance by bears at different spatial and temporal scales.

Harvest by means of hunting is a commonly used tool in large carnivore management. To evaluate the effects of harvest on populations, managers usually focus on numerical or immediate direct demographic effects of harvest mortality on a population's size and growth. However, we suggest that managers should also give consideration to indirect and potential evolutionary effects of hunting (e.g., the consequences of a change in the age, sex, and social structure), and their effects on population growth rate. We define “indirect effects” as hunting-induced changes in a population, including human-induced selection, that result in an additive change to the population growth rate “lambda” beyond that due to the initial offtake from direct mortality. We considered 4 major sources of possible indirect effects from hunting of bears: (1) changes to a population's age and sex structure, (2) changes to a population's social structure, (3) changes in individual behavior, and (4) human-induced selection. We i...

Adaptive management’, which has been defined as the repeated iteration between management action, scientific assessment and revised management action, leading to a strengthened foundation for management, is required by Swedish law to be incorporated into the management of large carnivores. We have evaluated whether the size and/or trend of the brown bear Ursus arctos population in Sweden corresponded to management-decided national objectives during five management regimes during the past 70 years (1943–2013). We found that the objective had been met in only one period, when it had been worded very vaguely. During the last period studied (2008–2013), when management was carried out on the county level and adaptive management was required by the Swedish Government, four of six counties met their trend objectives, but only one of six met the population objectives, although one was close to meeting them. Sociological studies have documented major problems in communication among the members of the county delegations responsible for the management of large carnivores. As adaptive management apparently never has been implemented successfully in brown bear management in Sweden, we recommend that the Delegations for Game Management be mandated to integrate up-to-date, scientifically documented biological information into their decisions. This is not done consistently today. Researchers should be involved in the process to inform about relevant, available information, design testable scientific ‘experiments’ based on the predicted results of management decisions, and evaluate the results in relation to the predictions, perhaps as members of a ‘boundary organization’ consisting of researchers, managers and stakeholders. This would require a new management paradigm, because many in Sweden seem to be skeptical to the idea of involving researchers in management.

Wildlife may adapt activity patterns to daily and seasonal variations in environmental factors and human activity. At the daily scale, diurnal or nocturnal activity can be a response to variations in food availability and/or human avoidance. At the seasonal scale, variation in prey vulnerability underlies the influence of predators on prey population dynamics, which is of management concern when predation affects domestic species. We analyzed the movement patterns of 133 GPS-collared brown bears in three study areas in Sweden in spring, when bears prey on the calves of domestic reindeer and moose, and in summer–early fall, when bears rely mostly on berries, in three areas with a gradient of human disturbance. In spring, the bears' daily movement patterns and time of predation on ungulates overlapped. In summer–early fall, when bears are hyperphagic to store fat for hibernation and reproduction, variation in the degree of nocturnal behavior among study areas likely reflected behavioral adjustments to reduce the risk of encountering people. Flexibility in daily movement patterns by large carnivores may help them survive in human-dominated landscapes, but behavioral changes may also reflect environmental degradation, for example human disturbance influencing foraging opportunities. Diurnal human activity disturbs the carnivores, but that does not hinder depredation on reindeer, because it occurs mostly at night. Thus, ideally carnivores and reindeer should be separated spatially to reduce depredations. A zoning system prioritizing carnivore conservation and reindeer herding in different areas might help reduce a long-lasting conflict.

Human persecution and habitat loss have endangered large carnivore populations worldwide, but some are recovering, exacerbating old conflicts. Carnivores can injure and kill people; the most dramatic form of wildlife-human conflict. In Scandinavia, the brown bear (Ursus arctos) population increased from ~500 bears in 1977 to ~3300 in 2008, with an increase in injuries, fatalities, and public fear of bear attacks. We reviewed media coverage and interviewed victims to explore how bear population trends, hunter education, and other factors may have influenced the number of injuries and fatalities in Scandinavia from 1977 to 2016. We found 42 incidents with 42 injuries and 2 fatalities; 42 were adult men, one was an adult woman conducting forestry work, and one was a boy skiing off-piste. Thirty-three adult men were hunting bears, moose, or small game, often with a hunting dog, and 26 had shot at the bear at 8±11 m before injury. Eleven nonhunters were conducting forestry work, inspecting a hunting area, picking berries, tending livestock, hiking, harassing a denned bear, and one person was killed outside his house at night. Eight of the 11 incidents of nonhunters involved female bears with cubs; three of these family groups were in dens and two were on carcasses. The annual number of hunters injured/killed was mostly influenced by the increase in the bear population size. The pattern was similar regarding injuries/fatalities to other outdoor users, but the relation with the bear population size was weaker than for hunters, and the null model was equally supported. Bear physiology at denning may make encounters with bears more risky in the fall, when bears show prehibernation behavior. Awareness and education efforts, especially among hunters, seem important to ensure human safety. Recreationists and forestry workers should avoid dense vegetation or make noise to warn bears of their presence.

Across Europe, wild boar numbers increased in the 1960s-1970s but stabilised in the 1980s; recent evidence suggests that the numbers and impact of wild boar has grown steadily since the 1980s. As hunting is the main cause of mortality for this species, we reviewed wild boar hunting bags and hunter population trends in 18 European countries from 1982 to 2012. Hunting statistics and numbers of hunters were used as indicators of animal numbers and hunting pressure. The results confirmed that wild boar increased consistently throughout Europe, while the number of hunters remained relatively stable or declined in most countries. We conclude that recreational hunting is insufficient to limit wild boar population growth and that the relative impact of hunting on wild boar mortality had decreased. Other factors, such as mild winters, reforestation, intensification of crop production, supplementary feeding and compensatory population responses of wild boar to hunting pressure might also explain population growth. As populations continue to grow, more human-wild boar conflicts are expected unless this trend is reversed. New interdisciplinary approaches are urgently required to mitigate human-wild boar conflicts, which are otherwise destined to grow further.

1. There is a growing recognition of the importance of indirect effects from hunting on wildlife populations, e.g., social and behavioral changes due to harvest, which occur after the initial offtake. Nonetheless, little is known about how the removal of members of a population influences the spatial configuration of the survivors. 2. We studied how surviving brown bears (Ursus arctos) used former home ranges that had belonged to casualties of the annual bear hunting season in southcentral Sweden (2007-2015). We used resource selection functions to explore the effects of the casualty's and survivor's sex, age, and their pairwise genetic relatedness, population density, and hunting intensity on survivors' spatial responses to vacated home ranges. 3. We tested the competitive release hypothesis, whereby survivors that increase their use of a killed bear’s home range are presumed to have been released from intraspecific competition. We found strong support for this hypothesis, as survivors of the same sex as the casualty consistently increased their use of its vacant home range. Patterns were less pronounced or absent when the survivor and casualty were of opposite sex. 4. Genetic relatedness between the survivor and the casualty emerged as the most important factor explaining increased use of vacated male home ranges by males, with a stronger response from survivors of lower relatedness. Relatedness was also important for females, but it did not influence use following removal; female survivors used home ranges of higher related female casualties more, both before and after death. Spatial responses by survivors were further influenced by bear age, population density, and hunting intensity. 5. We have showed that survivors exhibit a spatial response to vacated home ranges caused by hunting casualties, even in non-territorial species such as the brown bear. This spatial reorganization can have unintended consequences for population dynamics and interfere with management goals. Altogether, our results underscore the need to better understand the shortand long-term indirect effects of hunting on animal social structure and their resulting distribution in space.

Context: Methods for detecting contemporary, fine-scale population genetic structure in continuous populations are scarce. Yet such methods are vital for ecological and conservation studies, particularly under a changing landscape. Objectives: Here we present a novel, spatially explicit method that we call landscape relatedness (LandRel). With this method, we aim to detect contemporary, fine-scale population structure that is sensitive to spatial and temporal changes in the landscape. Methods: We interpolate spatially determined relatedness values based on SNP genotypes across the landscape. Interpolations are calculated using the Bayesian inference approach integrated nested Laplace approximation. We empirically tested this method on a continuous population of brown bears (Ursus arctos) spanning two counties in Sweden. Results: Two areas were identified as differentiated from the remaining population. Further analysis suggests that inbreeding has occurred in at least one of these areas. Conclusions: LandRel enabled us to identify previously unknown fine-scale structuring in the population. These results will help direct future research efforts, conservation action and aid in the management of the Scandinavian brown bear population. LandRel thus offers an approach for detecting subtle population structure with a focus on contemporary, fine-scale analysis of continuous populations. © The Author(s) 2016. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

The increase and range extension of wolves (Canis lupus L) and brown bears ( Ursus arctos L) in Scandinavia inevitably impacts moose (Alces alces L.) populations and, as a consequence, the size and composition of the hunter harvest must be adjusted. We used a sex- and age-structured moose population model to delineate optimal harvest strategies under predation and to compare the resulting harvest composition with the strategy commonly implemented in practice. We examined how much moose density or adult sex ratio needs to change to fully compensate for losses to predation. We found a harvest allocation pattern in commonly used practical management across calves, bulls and cows that indicated a trade-off strategy between maximising the number of shot moose, the yield biomass and the number of shot prime bulls. This strategy performed quite well with respect to all yield measures and yielded an age structure most similar to the strategies maximising harvest biomass and prime bulls. Unless predation pressure was very high, the harvest loss could be completely compensated for by allowing a higher moose density. In other situations the current hunting strategy was not possible to implement and the moose density needed to sustain predation even without hunting increases dramatically. An alternative option to balance the predation loss was to accept a more female-biased sex ratio in the winter population. Hence, it may be possible to keep 50% calves in the harvest and still obtain the same total harvest if the proportion of bulls in the harvest is increased to compensate for predation. The increase of large carnivores competing with moose hunting creates conflicts and will inevitably reduce harvest yield unless hunting strategies change. We show how increased moose density and redistribution of the harvest towards bulls can mitigate this conflict and we provide a web-based tool, where stakeholders can compare the long-term effects of alternative management decisions and eventually adjust their hunting strategy accordingly. (C) 2013 Elsevier B.V. All rights reserved.

Summary 1. Some large carnivore populations are increasing in Europe and North America, and minimizing interactions between people and carnivores is a major management task. Analysing the effects of human disturbance on wildlife from a predator–prey perspective is also of conservation interest, because individual behavioural responses to the perceived risk of predation may ultimately influence population distribution and demography. 2. The Scandinavian brown bear population provides a good model to study the interactions between an expanding large carnivore population, and people who use forests extensively for professional and recreational activities. We experimentally approached 52 GPS-collared brown bears (293 approaches on foot) from 2006 to 2011, to document the reaction of bears and quantify the effect of disturbance on bear movements. 3. None of the bears reacted aggressively to the observers. Although the location of the animals was known, bears were usually in quite concealed spots and were physically detected in only 16% of the approaches (seen in 42 approaches; heard in 6). However, the bears altered their daily movement patterns after the approaches. Bears increased movement at night-time and moved less at daytime, which was most visible in days 1 and 2 after the approaches, altering their foraging and resting routines. 4. Synthesis and applications. We provide experimental evidence on the effect of human disturbance on a large carnivore. The lack of aggressive reactions to approaching observers reinforces the idea that European brown bears generally avoid people, although bears can respond aggressively if they feel threatened (e.g. when wounded). However, the movement patterns of the bears changed after disturbance. Separating large carnivores and people temporally and spatially is an important goal for conservation and management. Conserving the shrub cover that provides concealment to the carnivores and keeping people away from the most densely vegetated spots in the forests is a way to avoid encounters between carnivores and people, therefore promoting human safety and carnivore conservation.

Background: Sarcoptic mange, a parasitic disease caused by the mite Sarcoptes scabiei, is regularly reported on wolves Canis lupus in Scandinavia. We describe the distribution and transmission of this parasite within the small but recovering wolf population by analysing 269 necropsy reports and performing a serological survey on 198 serum samples collected from free-ranging wolves between 1998 and 2013. Results: The serological survey among 145 individual captured Scandinavian wolves (53 recaptures) shows a consistent presence of antibodies against sarcoptic mange. Seropositivity among all captured wolves was 10.1 % (CI. 6.4 %–15.1 %). Sarcoptic mange-related mortality reported at necropsy was 5.6 % and due to secondary causes, predominantly starvation. In the southern range of the population, seroprevalence was higher, consistent with higher red fox densities. Female wolves had a lower probability of being seropositive than males, but for both sexes the probability increased with pack size. Recaptured individuals changing from seropositive to seronegative suggest recovery from sarcoptic mange. The lack of seropositive pups (8–10 months, N = 56) and the occurrence of seropositive and seronegative individuals in the same pack indicates interspecific transmission of S. scabiei into this wolf population. Conclusions: We consider sarcoptic mange to have little effect on the recovery of the Scandinavian wolf population. Heterogenic infection patterns on the pack level in combination with the importance of individualbased factors (sex, pack size) and the north–south gradient for seroprevalence suggests low probability of wolf-to-wolf transmission of S. scabiei in Scandinavia.

Humans are important agents of wildlife mortality, and understanding such mortality is paramount for effective population management and conservation. However, the spatial mechanisms behind wildlife mortality are often assumed rather than tested, which can result in unsubstantiated caveats in ecological research (e.g. fear ecology assumptions) and wildlife conservation and/or management (e.g. ignoring ecological traps). We investigated spatial patterns in human-caused mortality based on 30 years of brown bear Ursus arctos mortality data from a Swedish population. We contrasted mortality data with random locations and global positioning system relocations of live bears, as well as between sex, age and management classes (‘problem’ versus ‘no problem’ bear, before and after changing hunting regulations), and we used resource selection functions to identify potential ecological sinks (i.e. avoided habitat with high mortality risk) and traps (i.e. selected habitat with high mortality risk). We found that human-caused mortality and mortality risk were positively associated with human presence and access. Bears removed as a management measure were killed in closer proximity to humans than hunter-killed bears, and supplementary feeding of bears did not alter the spatial structure of human-caused bear mortality. We identified areas close to human presence as potential sink habitat and agricultural fields (oat fields in particular) as potential ecological traps in our study area. We emphasize that human-caused mortality in bears and maybe in wildlife generally can show a very local spatial structure, which may have far-reaching population effects. We encourage researchers and managers to systematically collect and geo-reference wildlife mortality data, in order to verify general ecological assumptions and to inform wildlife managers about critical habitat types. The latter is especially important for vulnerable or threatened populations.

1. Understanding the role of predation in shaping the dynamics of animal communities is a fundamental issue in ecological research. Nevertheless, the complex nature of predator–prey interactions often prevents researchers from modelling them explicitly. 2. By using periodic Leslie–Usher matrices and a simulation approach together with parameters obtained from long-term field projects, we reconstructed the underlying mechanisms of predator–prey demographic interactions and compared the dynamics of the roe deer–red fox–Eurasian lynx–human harvest system with those of the moose–brown bear–gray wolf–human harvest system in the boreal forest ecosystem of the southern Scandinavian Peninsula. 3. The functional relationship of both roe deer and moose λ to changes in predation rates from the four predators was remarkably different. Lynx had the strongest impact among the four predators, whereas predation rates by wolves, red foxes, or brown bears generated minor variations in prey population λ. Elasticity values of lynx, wolf, fox and bear predation rates were −0·157, −0·056, −0·031 and −0·006, respectively, but varied with both predator and prey densities. 4. Differences in predation impact were only partially related to differences in kill or predation rates, but were rather a result of different distribution of predation events among prey age classes. Therefore, the age composition of killed individuals emerged as the main underlying factor determining the overall per capita impact of predation. 5. Our results confirm the complex nature of predator–prey interactions in large terrestrial mammals, by showing that different carnivores preying on the same prey species can exert a dramatically different demographic impact, even in the same ecological context, as a direct consequence of their predation patterns. Similar applications of this analytical framework in other geographical and ecological contexts are needed, but a more general evaluation of the subject is also required, aimed to assess, on a broader systematic and ecological range, what specific traits of a carnivore are most related to its potential impact on prey species.

Studies of the effects and population dynamics of invasive species typically cover only short time periods. However, populations of invasive species interact with native species, and these interactions may have strong effects on invaders’ populations and effects over time. We present and analyze long-term data on invasive American mink (Neovison vison), native red fox (Vulpes vulpes), and mountain hare (Lepus timidus) in Sweden. The mink’s population dynamics followed a pattern of logistic growth from the late 1930s to the late 1970s. In the early 1980s, however, the population tripled, then declined sharply. We suggest that the mink’s population tripling was caused by a drastic decline in red fox populations, which caused terrestrial prey to increase. Later recovery of the fox population reversed the trend and caused the mink population’s recent decline. Our study shows that species interactions between native and invasive species, and therefore biotic resistance, can change dramatically over time.

Mean willingness-to-pay (WTP) based on multiple bounded, discrete choice responses from contingent valuation surveys are normally obtained using some kind of parametric estimator. This paper instead exploits the possibility to interpret the response to the discrete-choice question as an implicit contract between the researcher and the respondent, resulting in a minimum legal WTP (MLW) estimator. Never previously used in valuation literature, it is used in this paper to estimate the WTP for the preservation of large carnivores in Sweden, based on a large scale, national survey. Results show that MLW estimates only were 12–19% of the comparable parametric estimates. In keeping with other results in contingent valuation literature, we find that the MLW estimates are positively related to the educational level, income and the fraction of urban population, while negatively related to age. Among the advantages of the MLW estimator is its transparency as well as the fact that it rests on a contractual notion of WTP.

Human persecution is a major cause of mortality for large carnivores. Consequently, large carnivores avoid humans, but may use human-dominated landscapes by being nocturnal and elusive. Behavioral studies indicate that certain ecological systems are "landscapes of fear", driven by antipredator behavior. Because behavior and physiology are closely interrelated, physiological assessments may provide insight into the behavioral response of large carnivores to human activity. To elucidate changes in brown bears' (Ursus arctos) behavior associated with human activity, we evaluated stress as changes in heart rate (HR) and heart rate variability (HRV) in 12 GPS-collared, free-ranging bears, 7 males and 5 females, 3-11 years old, using cardiac-monitoring devices. We applied generalized linear regression models with HR and HRV as response variables and chest activity, time of day, season, distance traveled, and distance to human settlements from GPS positions recorded every 30 min as potential explanatory variables. Bears exhibited lower HRV, an indication of stress, when they were close to human settlements and especially during the berry season, when humans were more often in the forest, picking berries and hunting. Our findings provide evidence of a human-induced landscape of fear in this hunted population of brown bears.

The Scandinavian brown bear went through a major decline in population size approximately 100 years ago, due to intense hunting. After being protected, the population subsequently recovered and today numbers in the thousands. The genetic diversity in the contemporary population has been investigated in considerable detail, and it has been shown that the population consists of several subpopulations that display relatively high levels of genetic variation. However, previous studies have been unable to resolve the degree to which the demographic bottleneck impacted the contemporary genetic structure and diversity. In this study, we used mitochondrial and microsatellite DNA markers from pre- and postbottleneck Scandinavian brown bear samples to investigate the effect of the bottleneck. Simulation and multivariate analysis suggested the same genetic structure for the historical and modern samples, which are clustered into three subpopulations in southern, central and northern Scandinavia. However, the southern subpopulation appears to have gone through a marked change in allele frequencies. When comparing the mitochondrial DNA diversity in the whole population, we found a major decline in haplotype numbers across the bottleneck. However, the loss of autosomal genetic diversity was less pronounced, although a significant decline in allelic richness was observed in the southern subpopulation. Approximate Bayesian computations provided clear support for a decline in effective population size during the bottleneck, in both the southern and northern subpopulations. These results have implications for the future management of the Scandinavian brown bear because they indicate a recent loss in genetic diversity and also that the current genetic structure may have been caused by historical ecological processes rather than recent anthropogenic persecution.

Selecting the right habitat in a risky landscape is crucial for an individual's survival and reproduction. In predator–prey systems, prey often can anticipate the habitat use of their main predator and may use protective associates (i.e. typically an apex predator) as shields against predation. Although never tested, such mechanisms should also evolve in systems in which sexual conflict affects offspring survival. Here, we assessed the relationship between offspring survival and habitat selection, as well as the use of protective associates, in a system in which sexually selected infanticide (SSI), rather than interspecific predation, affects offspring survival. We used the Scandinavian brown bear ( Ursus arctos ) population with SSI in a human-dominated landscape as our model system. Bears, especially adult males, generally avoid humans in our study system. We used resource selection functions to contrast habitat selection of GPS-collared mothers that were successful (i.e. surviving litters, n = 19) and unsuccessful (i.e. complete litter loss, n = 11) in keeping their young during the mating season (2005–2012). Habitat selection was indeed a predictor of litter survival. Successful mothers were more likely to use humans as protective associates, whereas unsuccessful mothers avoided humans. Our results suggest that principles of predator–prey and fear ecology theory (e.g. non-consumptive and cascading effects) can also be applied to the context of sexual conflict.

1. Spatiotemporal segregation is often explained by the risk for offspring predation or by differences in physiology, predation risk vulnerability or competitive abilities related to size dimorphism. 2. Most large carnivores are size dimorphic and offspring predation is often intraspecific and related to nonparental infanticide (NPI). NPI can be a foraging strategy, a strategy to reduce competition, or a male reproductive strategy. Spatiotemporal segregation is widespread among large carnivores, but its nature remains poorly understood. 3. We evaluated three hypotheses to explain spatiotemporal segregation in the brown bear, a size-dimorphic large carnivore in which NPI is common; the ‘NPI – foraging/competition hypothesis', i.e. NPI as a foraging strategy or a strategy to reduce competition, the ‘NPI – sexual selection hypothesis’, i.e. infanticide as a male reproductive strategy and the ‘body size hypothesis’, i.e. body-size-related differences in physiology, predation risk vulnerability or competitive ability causes spatiotemporal segregation. To test these hypotheses, we quantified spatiotemporal segregation among adult males, lone adult females and females with cubs-of-the-year, based on GPS-relocation data (2006–2010) and resource selection functions in a Scandinavian population. 4. We found that spatiotemporal segregation was strongest between females with cubs-of-the-year and adult males during the mating season. During the mating season, females with cubs-of-the-year selected their resources, in contrast to adult males, in less rugged landscapes in relative close proximity to certain human-related variables, and in more open habitat types. After the mating season, females with cubs-of-the-year markedly shifted their resource selection towards a pattern more similar to that of their conspecifics. No strong spatiotemporal segregation was apparent between females with cubs-of-the-year and conspecifics during the mating and the postmating season. 5. The ‘NPI – sexual selection hypothesis’ best explained spatiotemporal segregation in our study system. We suggest that females with cubs-of-the-year alter their resource selection to avoid infanticidal males. In species exhibiting NPI as a male reproductive strategy, female avoidance of infanticidal males is probably more common than observed or reported, and may come with a fitness cost if females trade safety for optimal resources.

Estimating population size and trends are key issues in the conservation and management of large carnivores. The rebounding brown bear Ursus arctos population in Sweden is monitored by two different systems, both relying on voluntary resources. Population estimates have been calculated using Capture-Mark-Recapture methods, based on DNA-based scat surveys in five of the six Swedish counties with established bear populations. A total of 1,358 genotypes were identified using DNA extracted from collected scats. An independent ongoing programme, the Large Carnivore Observation Index (LCOI), was initiated in 1998. The LCOI uses effort-corrected observations of bears by moose Alces alces hunters during the moose hunt (> 2 million observation hours/year) and has shown a good correlation with relative population density of bears using the DNA-based method. From this, we have calculated population trends during the period 1998-2007. Using an exponential model, we estimated the yearly increase in the bear p...

Brown bears (Ursus arctos) are threatened by habitat loss, habitat fragmentation by infrastructure and human settlements, and have been hunted to local extinction in large areas of their former range. We analyzed the habitat use during the non denning period of 106 radio-collared bears in an expanding bear population in Sweden in relation to resorts and towns, terrain ruggedness, sex and age of bears. Bear use increased substantially with increasing distance to towns and resorts for comparable habitat and terrain types, also for independent scat surveys using DNA-analyses. More than 74% of all female bear locations were in the 29% of the terrain classified as ‘‘rugged’’ and located >10 km from any town or resort, whereas similar habitat closer to towns or resorts was avoided. Bears closer to larger settlements and resorts ( 7 years), the remaining 92% located beyond 10 km from major resorts and settlements. Recreational resorts are developing rapidly, typically near national parks, and may thus limit expansion or fragment existing bear habitats. Together with active conservation, safeguarding undeveloped corridors of forest and rugged terrain may be important for successful recolonization of the brown bear into its original range.

Interspecific competition can influence the distribution and abundance of species and the structure of ecological communities and entire ecosystems. Interactions between apex predators can have cascading effects through the entire natural community, which supports broadening the scope of conservation from single species to a much wider ecosystem perspective. However, competition between wild large carnivores can hardly be measured experimentally. In this study, we analyzed the expansion of the Scandinavian wolf ( Canis lupus ) population during its recovery from the early 1990s. We took into account wolf-, habitat-, human- and brown bear ( Ursus arctos )-related factors, because wolf expansion occurred within an area partially sympatric with bears. Wolf pair establishment was positively related to previous wolf presence and was negatively related to road density, distance to other wolf territories, and bear density. These findings suggest that both human-related habitat modification and interspecific competition have been influential factors modulating the expansion of the wolf population. Interactions between large carnivores have the potential to affect overall biodiversity. Therefore, conservation-oriented management of such species should consider interspecific interactions, rather than focusing only on target populations of single species. Long-term monitoring data across large areas should also help quantify and predict the influence of biotic interactions on species assemblages and distributions elsewhere. This is important because interactive processes can be essential in the regulation, stability, and resilience of ecological communities