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While wildlife and cultural preservation goals can be either complimentary orcounteractive, the goals of large carnivore conservation and traditional pastoralist lifestyles are often at odds. Livestock depredation can negatively impact the economies of livestock herders, while subsequent lethal removals contribute to local carnivore population declines. Here, we collaborated with two Sami reindeer herding communities (2010–2016) situated in Sweden’s boreal forest to evaluate the efficacy and economic feasibility of three brown bear predation mitigation measures: corralling pregnant reindeer during parturition, lethal bear management removals, and public bear-license hunting. Calving corrals increased survival for reindeer calves born to average-sized females by 7%–15%, and by 14%–30% for calves born to small females. However, the realized cost of implementing calving corrals outweighed the financial gain for both our study areas (net losses ranged between €1111 and €6210 per calf saved from bear predation per year when using the updated 2021 calf value; 1€ [Euro] = US$1.1), as well as for almost every theoretical scenario we explored (net losses €234 and €13,995 per calf saved from bear predation). The exception was the theoretical scenario where small herding communities overlapped large bear populations, which crossed the breakeven efficacy bear/reindeer ratio of 13.5 bears/100 reindeer and had a potential net gain of €36 per saved calf. Similarly, the cost of lethal management removals of bears outweighed the potential financial gain from saved calves, with net losses between €75 and €239 per calf. License hunting, where the hunters voluntarily incur the monetary costs of removing bears, is in most cases the only economically viable mitigation measure where the cost of mitigation did not outweigh the financial gain from increased reindeer survival. While the annual public license hunt was the most cost-effective mitigation measure, it may be less biologically effective, that is, bear hunting occurs in the fall and reindeer parturition the following spring which leaves time for the empty niche of harvested bears to be filled by survivors. Economically and biologically effective predation mitigation measures are key for promoting coexistence, and we suggest that potential mitigation measures should be studied in collaboration with local people. brown bear, calving corrals, economic feasibility, management removal, predation, reindeer herding

Competition between apex predators can alter the strength of top-down forcing, yet we know little about the behavioral mechanisms that drive competition in multipredator ecosystems. Interactions between predators can be synergistic (facilitative) or antagonistic (inhibitive), both of which are widespread in nature, vary in strength between species and across space and time, and affect predation patterns and predator-prey dynamics. Recent research has suggested that gray wolf (Canis lupus) kill rates decrease where they are sympatric with brown bears (Ursus arctos), however, the mechanisms behind this pattern remain unknown. We used data from two long-term research projects in Scandinavia (Europe) and Yellowstone National Park (North America) to test the role of interference and exploitation competition from bears on wolf predatory behavior, where altered wolf handling and search time of prey in the presence of bears are indicative of interference and exploitation competition, respectively. Our results suggest the mechanisms driving competition between bears and wolves were dependent on the season and study system. During spring in Scandinavia, interference competition was the primary mechanism driving decreased kill rates for wolves sympatric with bears; handling time increased, but search time did not. In summer, however, when both bear and wolf predation focused on neonate moose, the behavioral mechanism switched to exploitation competition; search time increased, but handling time did not. Alternartively, interference competition did affect wolf predation dynamics in Yellowstone during summer, where wolves prey more evenly on neonate and adult ungulates. Here, bear presence at a carcass increased the amount of time wolves spent at carcasses of all sizes and wolf handling time for small prey, but decreased handling time for the largest prey. Wolves facilitate scavenging opportunities for bears, however, bears alter wolf predatory behavior via multiple pathways and are primarily antagonistic to wolves. Our study helps to clarify the behavioral mechanisms driving competition between apex predators, illustrating how interspecific interactions can manifest into population-level predation patterns.

Reliable data and methods for assessing changes in wildlife population size over time are necessary for management and conservation. For most species, assessing abundance is an expensive and labor-intensive task that is not affordable on a frequent basis. We present a novel approach to reconstructing brown bear population dynamics in Slovenia in the period 1998-2019, based on the combination of two CMR non-invasive genetic estimates (in 2007 and 2015) and long-term mortality records, to show how the latter can help the study of population dynamics in combination with point-in-time estimates. The spring (i.e. including newborn cubs) population size estimate was 383 (CI: 336-432) bears in 1998 and 971 (CI: 825-1161) bears in 2019. In this period, the average annual population growth rate was 4.5 %. The predicted population size differed by just 7 % from the non-invasive genetic size estimate after eight years, suggesting that the method is reliable. It can predict the evolution of the population size under different management scenarios and provide information on key parameters, e.g. background mortality and the sex- and age-structure of the population. Our approach can be used for several other wildlife species, but it requires reliable mortality data over time. Za upravljanje in ohranjanje populacij prostoživečih živali so potrebni zanesljivi podatki in metode za ocenjevanje njihove številčnosti. Ugotavljanje številčnosti je pri večini vrst drago in zahtevno, zato ga ni mogoče pogosto izvajati. V članku predstavljamo nov pristop, ki smo ga pripravili na primeru rekonstrukcije populacijske dinamike rjavega medveda v Sloveniji v obdobju 1998-2019. Pristop temelji na kombinaciji dveh ocen njegove številčnosti z neinvazivnimi genetskimi metodami (v letih 2007 in 2015) in dolgoletnega niza podatkov monitoringa smrtnosti. Ocena 'pomladanske' (t.j. največje letne - po poleganju mladičev) številčnosti rjavega medveda v Sloveniji za leto 1998 znaša 383 (CI: 336-432), za leto 2019 pa 971 osebkov (CI: 825-1161). Povprečna letna stopnja rasti populacije je bila v tem obdobju 4,5 %. Modelno ocenjena številčnost populacije se je od ugotovljene z genetsko metodo po osmih letih razlikovala le za 7 %, kar nakazuje, da je pristop zanesljiv oz. so njegovi rezultati za upravljavske namene dovolj kakovostni. Pristop omogoča tudi napovedovanje prihodnje populacijske dinamike pri različnih scenarijih upravljanja in okvirno ocenjevanje ključnih populacijskih parametrov, kot so spolna in starostna sestava, relativna rodnost in naravna smrtnost populacije. Pristop je uporaben tudi za več drugih populacij in živalskih vrst, vendar so zanj potrebni zanesljivi dolgoletni podatki o smrtnosti.

XV Congreso de la Sociedad Española para la Conservación y Estudio de los Mamíferos (SECEM), Córdoba, 4-7 diciembre de 2021.

XV Congreso de la Sociedad Española para la Conservación y Estudio de los Mamíferos (SECEM), Córdoba, 4-7 diciembre de 2021.

The organization of ecological assemblages has important implications for ecosystem functioning, but little is known about how scavenger communities organize at the global scale. Here, we test four hypotheses on the factors affecting the network structure of terrestrial vertebrate scavenger assemblages and its implications on ecosystem functioning. We expect scavenger assemblages to be more nested (i.e. structured): 1) in species‐rich and productive regions, as nestedness has been linked to high competition for carrion resources, and 2) regions with low human impact, because the most efficient carrion consumers that promote nestedness are large vertebrate scavengers, which are especially sensitive to human persecution. 3) We also expect climatic conditions to affect assemblage structure, because some scavenger assemblages have been shown to be more nested in colder months. Finally, 4) we expect more organized assemblages to be more efficient in the consumption of the resource. We first analyzed the relationship between the nestedness of the scavenger assemblages and climatic variables (i.e. temperature, precipitation, temperature variability and precipitation variability), ecosystem productivity and biomass (i.e. NDVI) and degree of human impact (i.e. human footprint) using 53 study sites in 22 countries across five continents. Then, we related structure (i.e. nestedness) with its function (i.e. carrion consumption rate). We found a more nested structure for scavenger assemblages in regions with higher NDVI values and lower human footprint. Moreover, more organized assemblages were more efficient in the consumption of carrion. However, our results did not support the prediction that the structure of the scavenger assemblages is directly related to climate. Our findings suggest that the nested structure of vertebrate scavenger assemblages affects its functionality and is driven by anthropogenic disturbance and ecosystem productivity worldwide. Disarray of scavenger assemblage structure by anthropogenic disturbance may lead to decreases in functionality of the terrestrial ecosystems via loss of key species and trophic facilitation processes.

Habitat selection of animals depends on factors such as food availability, landscape features, and intra- and interspecific interactions. Individuals can show several behavioral responses to reduce competition for habitat, yet the mechanisms that drive them are poorly understood. This is particularly true for large carnivores, whose fine-scale monitoring is logistically complex and expensive. In Scandinavia, the home-range establishment and kill rates of gray wolves (Canis lupus) are affected by the coexistence with brown bears (Ursus arctos). Here, we applied resource selection functions and a multivariate approach to compare wolf habitat selection within home ranges of wolves that were either sympatric or allopatric with bears. Wolves selected for lower altitudes in winter, particularly in the area where bears and wolves are sympatric, where altitude is generally higher than where they are allopatric. Wolves may follow the winter migration of their staple prey, moose (Alces alces), to lower altitudes. Otherwise, we did not find any effect of bear presence on wolf habitat selection, in contrast with our previous studies. Our new results indicate that the manifestation of a specific driver of habitat selection, namely interspecific competition, can vary at different spatial-temporal scales. This is important to understand the structure of ecological communities and the varying mechanisms underlying interspecific interactions.

XIV Congreso de la Sociedad Española para la Conservación y Estudio de los Mamíferos (SECEM), Jaca, 5-8 diciembre de 2019., La comunicación mediada por olores se considera el principal canal de comunicación en muchas especies de mamíferos. En comparación con la comunicación visual y acústica, los olores persisten durante más tiempo, lo que permite a los individuos interactuar sin necesidad de superponerse simultáneamente en el espacio y el tiempo. El oso pardo (Ursus arctos), al igual que otros mamíferos, realiza principalmente una comunicación química a través de olores depositados en los árboles de marcaje (rubbing trees). En este estudio comparamos en primer lugar las características de 101 árboles de marcaje con 263 árboles “control” en la Cordillera Cantábrica (provincias de Asturias y León). Posteriormente analizamos los factores potenciales que afectan la densidad de los árboles de marcaje a lo largo de 35 rutas de prospección por pistas forestales y ganaderas. Partimos de las hipótesis de que: (1) los osos seleccionarían árboles específicos, o especies de árboles con características que los hagan destacar en el entorno; y (2) los árboles marcados serían más abundantes hacia el núcleo del área de distribución de osos y/o en áreas con mayor densidad de osos. Nuestros resultados mostraron que los osos pardos generalmente seleccionaron árboles más conspicuos, con mayor tamaño y aislamiento respecto a otros árboles y mostraron cierta preferencia por los abedules (Betula spp.). Esta elección puede facilitar el marcado y/o la detección de señales químicas y, por lo tanto, la efectividad de la comunicación intraespecífica. Por otro lado, la abundancia de árboles de marcaje a lo largo de las rutas no parecía depender de la densidad poblacional de los osos en el entorno o de su posición relativa dentro del subnúcleo de la población. Nuestros hallazgos también podrían ser útiles para localizar árboles objetivo que podrían ayudar en el monitoreo de la población, por ejemplo con la instalación de trampas de pelo o cámaras trampa.

XIV Congreso de la Sociedad Española para la Conservación y Estudio de los Mamíferos (SECEM), Jaca, 5-8 diciembre de 2019., El Grupo de Investigación del Oso Cantábrico, establecido en el Principado de Asturias desde 2014, cuenta en la actualidad con 19 personas (investigadores del CSIC y la Universidad de Oviedo, investigadores pre y postdoctorales, técnicos de campo). Desde sus comienzos el grupo ha recibido financiación para 4 proyectos, entre ellos un Proyecto de Excelencia del Plan Nacional para el estudio del oso pardo en la Cordillera Cantábrica bajo la perspectiva de la coexistencia entre humanos y grandes carnívoros en ambientes humanizados, y un proyecto sobre su comportamiento financiado por la IBA. Este grupo nace de la urgente necesidad de un proyecto de investigación a largo plazo sobre el oso en la Cordillera. Aunque en las décadas anteriores distintos grupos e investigadores han producido material científico de indudable valor, nunca se ha dado el paso desde un enfoque puntual y aleatorio a una investigación de amplio espectro estrictamente ligada a la conservación. En esta comunicación se presentarán algunos estudios llevados a cabo por el grupo: (1) Selección de hábitat y expansión potencial del oso en Asturias con modelos de máxima entropía, en el que se comprueba que quedan hasta 5.000 km2 disponibles para su expansión, especialmente en la zona oriental (77%), ya que en la occidental casi el 80% del hábitat disponible ya está ocupado por la especie; (2) comportamiento de los osos en la Cordillera (80h de vídeos grabados durante más de 10 años, en los que se ha observado que los osos no aumentan la alerta cerca de zonas de alta actividad humana, lo que sugiere que en estas zonas están relativamente bien adaptados a coexistir con los humanos; (3) características de reproducción y hábitat de las hembras con crías, en los que se concluye que (a) el tamaño medio de la camada es relativamente parecido entre las zonas occidental y la oriental, (b) la mortalidad media de las crías es de 0,2±0,5 y (c) que las hembras con crías recién salidas de la osera utilizan hábitats similares a los de los adultos durante el celo, lo que podría representar una “trampa ecológica” que aumentaría la posibilidad de infanticidios. En otros estudios en desarrollo se está investigando sobre (1) marcaje, (2) factores espacio-temporales de daños o (3) estado parasitario de la población de osos cantábrica.

Vi undersøkte hvorvidt graden av menneskelig påvirkning i skandinaviske ulvers oppvekstrevir kunne forklare noe av variasjonen i deres habitatvalg og områdebruk i forhold til menneskelig aktivitet og infrastruktur. Først testet vi hypotesen om oppvekstpåvirket habitatpreferanse (OPHP) ved etablering av eget revir, det vil si hvorvidt ulver under spredning var påvirket av egenskaper ved oppvekstreviret, deriblant faktorer relatert til menneskelig aktivitet, når de valgte å etablere seg i eget revir. Siden spredningsavstand kan ha en betydning for likhetsgraden mellom oppvekstrevir og etablert revir, og hanner ofte sprer seg lenger enn hunner, testet vi om spredningsavstand og kjønn kan være av betydning, og vi testet ulike metoder for å definere tilgjengelig habitat. Deretter testet vi hypotesen om OPHP ved ulvers habitatvalg innenfor det etablerte reviret, med to konkurrerende hypoteser: A) Ulver som er eksponert for høy grad av menneskelig aktivitet i oppvekstreviret vil senere unngå menneskelig aktivitet og infrastruktur innenfor sitt etablerte revir. B) Ulver som er eksponert for høy grad av menneskelig aktivitet i oppvekstreviret vil senere selektere for menneskelige strukturer i det etablerte reviret på grunn av en tilpasning eller habituering til menneskelig aktivitet. Vi fant at ulvetisper, og til en viss grad hanner, med kort spredningsavstand fra oppvekstreviret fortrinnsvis valgte å etablere revir i områder som lignet oppveksthabitatet, uavhengig av definisjonene på tilgjengelig habitat og habitatlikhet. Dette var ikke tilfellet for ulver som vandret over lengre avstander. Vi fant også svak men konsistent støtte for at ulvepar der tispa var oppvokst et område med stor grad av menneskelig aktivitet unngikk menneskelig påvirkning innenfor sitt etablerte revir. For hanner var dette mønsteret mindre tydelig. Noe av bakgrunnen for denne utredningen var en bekymring blant folk bosatt i ulveområder for om ulver som vokser opp i områder med stor grad av menneskelig aktivitet vil vise oppsøkende atferd overfor mennesker. Våre funn antyder derimot at ulver som er blitt eksponert for større grad av menneskelig påvirkning i oppvekstreviret muligens unngår nærhet til menneskelig bosetting og infrastruktur innenfor sine revir senere i livet. Metodene brukt i denne studien kan være nyttige for videre forskning på og forvaltningen av ulv i Skandinavia og andre steder, både for å vurdere om ulvenes respons på erfaring med menneskelig aktivitet endrer seg med eventuelle endringer i ulvebestanden eller menneskenes bosettingsmønstre, men også for å sammenligne ulvers respons i Skandinavia med andre deler av Europa der ulven er i ferd med å reetablere seg i områder med langt høyere befolkningstetthet. English: We investigated whether the degree of natal exposure to anthropogenic influences could explain some of the variation in the selection of habitat with regard to anthropogenic factors in Scandinavian wolves. In the first part of the study we tested whether anthropogenic influences in the natal habitat might affect the choice of a breeding territory. Because dispersal distance may influence habitat similarity between natal and established territories, and mammals often show male-biased dispersal, we investigated the importance of dispersal distance and sex, and we tested alternative methods for defining habitat availability. In the second part of the study we evaluated whether the natal habitat may affect the habitat selection of wolves within their established territories, and we tested two competing hypotheses. A) Wolves exposed to a high degree of human activity in the natal territory may avoid human-related features within their established territory. B) Wolves exposed to a high degree of human activity in the natal territory may select for human related features in the established territory because of a certain degree of adaptation or habituation to human activity. We found that female, and to a smaller degree male wolves with short dispersal distances established in natal-like habitat types, regardless of the definition of habitat availability and habitat similarity. This was not the case for wolves that dispersed longer distances. We also found weak but consistent statistical evidence that wolf pairs in which the female had dispersed from a natal territory with a high degree of anthropogenic influence tended to select areas further away from humans within their established territory. The effects of the natal territory of the males was less clear. Part of the background for this evaluation was a concern among people living in wolf areas that wolves growing up in areas with high anthropogenic influence would seek human activity. On the contrary, our results suggest that wolves that have been exposed to larger degrees of anthropogenic influence in the natal territory may avoid proximity to human settlements and infrastructure inside their established territories. Our methodological approach may be useful for the continued wolf research and management in Scandinavia and elsewhere, both for the monitoring of whether wolves’ response to exposure to humans changes following changes in the wolf population or in the patterns of human settlement, but also to compare the response of wolves in Scandinavia to those in other parts of Europe, in which wolves are recolonizing areas of much higher anthropogenic influence. Miljødirektoratet

XIV Congreso de la Sociedad Española para la Conservación y Estudio de los Mamíferos (SECEM), Jaca, 5-8 diciembre de 2019., El rascado en los árboles juega un papel fundamental en la comunicación intraespecífica de los osos pardos (Ursus arctos), cuyas áreas de campeo a menudo se encuentran solapadas. A través de estos mensajes, los osos son capaces de reconocer a todos los individuos de su zona sin necesidad de interacciones directas. Se ha demostrado que los osos pardos invierten una parte de su tiempo en la búsqueda activa de las señales químicas dejadas por los conspecíficos como parte esencial de su red de comunicación. El presente trabajo busca descubrir: (a) la red social existente en torno a los árboles de rascado (o árboles de marcaje) del occidente de la Cordillera Cantábrica (n= 18 árboles de rascado); (b) los patrones de marcaje a lo largo de todo el año (n= 32 árboles de rascado); así como(c) entender dinámicas de envejecimiento en la población sujeta a estudio, mediante la toma de muestras de pelo depositado en trampas no lesivas, situadas en Asturias y León, tras el rascado. La recogida de los pelos se ha realizado mensualmente durante un período de un año, por lo que disponemos de un volumen total de 216 muestras, cada una de ellas con material de distintos ejemplares de oso. Se ha realizado la extracción genética de cada pelo con un total de ocho folículos pilosos por muestra, de forma que la posibilidad de error disminuya al 5% y se obtenga una concentración de ADN nuclear suficiente para su identificación. Para la determinación del individuo, sexo y rango de edad se han escogido siete marcadores microsatélites, descritos como los más informativos para este fin. La población occidental es la que cuenta con el mayor número de individuos de la población pero, en base a los resultados preliminares y debido a la limitada variabilidad genética es necesario determinar si es suficiente para realizar una correcta identificación individual. Datos preliminares muestran que los patrones anuales en el rascado se han estudiado como una variable en torno a la época del año, siendo los meses de abril a septiembre de los que mayor cantidad de pelo se obtiene, así como en los meses en torno a la hibernación cuando se denota una reducción en el comportamiento de rascado coincidente con su disminución de actividad.

Identifying how sympatric species belonging to the same guild coexist is a major question of community ecology and conservation. Habitat segregation between two species might help reduce the effects of interspecific competition and apex predators are of special interest in this context, because their interactions can have consequences for lower trophic levels. However, habitat segregation between sympatric large carnivores has seldom been studied. Based on monitoring of 53 brown bears (Ursus arctos) and seven sympatric adult gray wolves (Canis lupus) equipped with GPS collars in Sweden, we analyzed the degree of interspecific segregation in habitat selection within their home ranges in both late winter and spring, when their diets overlap the most. We used the K‐select method, a multivariate approach that relies on the concept of ecological niche, and randomization methods to quantify habitat segregation between bears and wolves. Habitat segregation between bears and wolves was greater than expected by chance. Wolves tended to select for moose occurrence, young forests, and rugged terrain more than bears, which likely reflects the different requirements of an omnivore (bear) and an obligate carnivore (wolf). However, both species generally avoided human‐related habitats during daytime. Disentangling the mechanisms that can drive interspecific interactions at different spatial scales is essential for understanding how sympatric large carnivores occur and coexist in human‐dominated landscapes, and how coexistence may affect lower trophic levels. The individual variation in habitat selection detected in our study may be a relevant mechanism to overcome intraguild competition and facilitate coexistence.

Supplementary information about the study area, definition of habitat availability and definition of habitat similarity

Vi undersøkte hvorvidt graden av menneskelig påvirkning i skandinaviske ulvers oppvekstrevir kunne forklare noe av variasjonen i deres habitatvalg og områdebruk i forhold til menneskelig aktivitet og infrastruktur. Først testet vi hypotesen om oppvekstpåvirket habitatpreferanse (OPHP) ved etablering av eget revir, det vil si hvorvidt ulver under spredning var påvirket av egenskaper ved oppvekstreviret, deriblant faktorer relatert til menneskelig aktivitet, når de valgte å etablere seg i eget revir. Siden spredningsavstand kan ha en betydning for likhetsgraden mellom oppvekstrevir og etablert revir, og hanner ofte sprer seg lenger enn hunner, testet vi om spredningsavstand og kjønn kan være av betydning, og vi testet ulike metoder for å definere tilgjengelig habitat. Deretter testet vi hypotesen om OPHP ved ulvers habitatvalg innenfor det etablerte reviret, med to konkurrerende hypoteser: A) Ulver som er eksponert for høy grad av menneskelig aktivitet i oppvekstreviret vil senere unngå menneskelig aktivitet og infrastruktur innenfor sitt etablerte revir. B) Ulver som er eksponert for høy grad av menneskelig aktivitet i oppvekstreviret vil senere selektere for menneskelige strukturer i det etablerte reviret på grunn av en tilpasning eller habituering til menneskelig aktivitet. Vi fant at ulvetisper, og til en viss grad hanner, med kort spredningsavstand fra oppvekstreviret fortrinnsvis valgte å etablere revir i områder som lignet oppveksthabitatet, uavhengig av definisjonene på tilgjengelig habitat og habitatlikhet. Dette var ikke tilfellet for ulver som vandret over lengre avstander. Vi fant også svak men konsistent støtte for at ulvepar der tispa var oppvokst et område med stor grad av menneskelig aktivitet unngikk menneskelig påvirkning innenfor sitt etablerte revir. For hanner var dette mønsteret mindre tydelig. Noe av bakgrunnen for denne utredningen var en bekymring blant folk bosatt i ulveområder for om ulver som vokser opp i områder med stor grad av menneskelig aktivitet vil vise oppsøkende atferd overfor mennesker. Våre funn antyder derimot at ulver som er blitt eksponert for større grad av menneskelig påvirkning i oppvekstreviret muligens unngår nærhet til menneskelig bosetting og infrastruktur innenfor sine revir senere i livet. Metodene brukt i denne studien kan være nyttige for videre forskning på og forvaltningen av ulv i Skandinavia og andre steder, både for å vurdere om ulvenes respons på erfaring med menneskelig aktivitet endrer seg med eventuelle endringer i ulvebestanden eller menneskenes bosettingsmønstre, men også for å sammenligne ulvers respons i Skandinavia med andre deler av Europa der ulven er i ferd med å reetablere seg i områder med langt høyere befolkningstetthet.

AICc model selection results

Summary of predation studies in Scandinavia and Yellowstone

Cluster searches and carcass cause of death

Parameter estimates (β, SE, and 95% CI) from the top models (Fig. 1)

Carnivore-human encounters that result in human injury present a conservation and management challenge and it is therefore important to understand under what conditions such incidents occur. Females with cubs are often involved when humans are injured by brown bears Ursus arctos. In Scandinavia, this is particularly true for unarmed recreational forest users. Our aim was to document behavioural differences between single bears and females with cubs in order to develop recommendations to minimize the risk of injuries to recreational forest users. We documented the reactions of GPS-collared females with cubs and single brown bears to experimental approaches by humans to 50 m from the bear on 42 and 108 occasions, respectively. The majority of females with cubs (95%) and single bears (89%) left when approached. Bears that left were passed at shorter distances and were in more open areas than those that stayed. Both groups had similar flight initiation distances, which were longer for bears that were active at the time of the disturbance. Females with cubs selected more open habitat than single bears, also for the new site they selected following disturbance. Females with cubs, particularly active females with cubs of the year, moved greater distances and spent more time active following the approach. Females with cubs and single bears were seen or heard in 26% and 14% of the approaches, respectively. None of the bears displayed any aggressive behaviour during the approaches. Females with cubs selected more open habitat, perhaps predisposing them to encountering people that are not involved in hunting activities, which might be the primary explanation why females with cubs are most frequently involved when unarmed people are injured by bears in Scandinavia. To mitigate injury risks, one must consider factors that bring bears closer to human activity in the first place.

In this thesis, I have compiled, summarized, and reviewed 322 cases of people killed and injured by brown bears (Ursus arctos) in Russia from 1932 to 2017. The focus was primarily on 256 bear-induced human casualties recorded between 1991 and 2017, because data availability varied between the Soviet and post-Soviet periods. I found that the annual number of human-bear incidents was positively associated with the area of forests burned annually and with the increase in the brown bear population, despite varying estimates of the bear population size during the study period. Between 1991 and 2017, bear-caused injuries and fatalities occurred more frequently on the Russian Pacific Coast (111 incidents) and in Siberia (104 incidents) than in European Russia (41 incidents), which had higher human density and fewer bears. Single bears were involved in most of the incidents (73%). Casualties occurred mainly during daytime and especially in summer and autumn. Human activities appeared to lead, directly or indirectly, to bear-caused human injuries and fatalities; in 182 incidents with documented probable causes bears most often attacked when provoked (41%), surprised (18%), and when bears preyed or attempted to prey upon humans (17%). During 1932-1990, hunters and outdoor workers were the main categories attacked by bears. Between 1991 and 2017, people who gathered wild resources and hiked were injured or killed more frequently in bear attacks. I emphasize the importance of educational programs where people can learn about bear biology and habits, better management of human activities in bear country, systematical collection of data on bear population dynamics, and preservation of bear habitat in order to minimize human-bear conflicts in Russia and elsewhere. M-ECOL

Apex carnivores are mostly recognized for their effects on ecosystem processes through altering population dynamics and behaviour of their prey. Apex carnivores may also affect lower trophic levels through the distribution of ungulate carcasses. Such direct effects of predation on lower trophic levels are, however, poorly understood. Ungulate carcasses typically disturb soil and vegetation locally and enrich the soil with nutrients, which affect composition of the vegetation. In this study, I assessed vegetation composition in relation to carcasses of wolf-killed (Canis lupus) moose (Alces alces) in the boreal forest in southcentral Sweden. I compared composition of vascular plants, bryophytes and lichens at 12 carcass sites, each one paired with a nearby (25-50m) control site without carcass. I recorded the abundance of all species within nine vegetation plots at each carcass and control site, with one plot placed at the kill spot. Using generalized linear mixed models, I found that the carcasses created intense local disturbances and reduced both field (vascular plants) and ground cover (bryophytes and lichens), with the most dramatic effect in the centre of the carcass plot. Carcasses presence accounted for 11% of the explained variation in the species composition, although the effects were very local. Results from a detrended correspondence analysis revealed that forest age was the most important gradient in explaining patterns in species composition. Disturbance from carcasses was the second most important. I used indicator value analysis to identify winners and losers of carcass presence, and found that seedlings of Betula pubescens/pendual and Pinus sylvestris were more abundant on the carcass centre plots than elsewhere. Additionally, three mosses were positively affected by carcass disturbance (Pohlia nutans, Bryum sp., Plagiomnium ellipticum), and one lichen (Cladonia arbuscula) was identified as a loser. The disturbance from carcasses showed several similarities with uprooting of trees, as it releases competitive interactions and makes space available for species regenerating from the diaspore bank. Because uprooting’s are rare in the heavily managed forest, this may increase the importance of carcasses as disturbances in the boreal forest. My results emphasize that apex predators can have important ecological roles other than numeric and trait mediated cascading effects, as predation events create local biogeochemical hotspots. This highlight the importance of conservation of apex predators in the ecosystem to keep ecosystem functioning intact. M-ECOL