The Wolf Intelligencer


Eurasian Brown Bear (Ursus arctos arctos)

Factors affecting the home range of Dinaric-Pindos brown bears. De Angelis D, Huber D, Reljic S, Ciucci P, Kusak J. Journal of Mammalogy. 2021 Mar 23


Studying how animals interact with their environment is fundamental to informing conservation and management efforts, especially when examining large, wide-ranging carnivores in human-dominated landscapes. We hypothesized that the home ranges of bears are configured to exploit supplemental food (corn) and avoid people. In 2004–2016, we tracked 10 brown bears from the Dinaric-Pindos population using GPS telemetry, then used Brownian bridge movement models to estimate their home ranges. We related seasonal home range size to circadian period and density of supplemental feeding sites using generalized linear mixed-effect models. We also used ecological-niche factor analysis to study habitat composition within home range core areas in study areas characterized by different levels of human encroachment. We found that home range size was inversely related to density of supplemental feeding sites, and bears had larger home ranges at night (x̅ = 103.3 ± 72.8 km2) than during the day (x̅ = 62.3 ± 16.6 km2). Our results also revealed that bears living in more human-influenced areas concentrated their use far from human settlements and agricultural lands but stayed close to supplemental feeding sites. Our data suggest that bears alter their space-use patterns at the home range level in response to anthropogenic land use and food availability.

Restoration of transborder connectivity for Fennoscandian brown bears (Ursus arctos). Kopatz A, Kleven O, Kojola I, Aspi J, Norman AJ, Spong G, Gyllenstrand N, Dalén L, Fløystad I, Hagen SB, Kindberg J.Biological Conservation. 2021 Jan


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.

Individual Variation in Predatory Behavior, Scavenging and Seasonal Prey Availability as Potential Drivers of Coexistence between Wolves and Bears. Ordiz Fernandez, A.A., Milleret, C.P., Uzal, A., Zimmermann, B., Wabakken, P., Wikenros, C., Sand, H., Swenson, J. and Kindberg, J., 2020.

Cholangiocarcinoma in a Free-Ranging Eurasian Brown Bear (Ursus arctos arctos) from Northern Spain. Balseiro A, Royo LJ, Gayo E, Marín JF. Journal of wildlife diseases. 2020 Jan
(Principality of Asturias, northern Spain)

Mortality in free-ranging Eurasian brown (Ursus arctos arctos) in Spain (1998-2018). Balseiro, A., Royo, L.J., Gayo, E., Balsera, R., Alarcia, O. and Marín, J.F.G., 2020 Jan
(Cantabrian mountain range submitted for necropsy in Asturias and Castilla y León, northwestern Spain. “Six out of the 20 (30%) brown bears died as a consequence of “human intervention” due to illegal hunting (wire snare hunting n =3 or shooting n =2) and, strychnine poisoning ( n =1). In contrast, fourteen (14/20, 70%) brown bears died by “non-human intervention”; nine of them (9/20, 45%) due to traumatic lesions (fights n =4, traumas n =3 or infanticide n =2), three (3/20, 15%) due to infectious canine hepatitis caused by canine adenovirus type 1 (CAdV-1) infection, one (1/20, 5%) due to cholangiocarcinoma and another one (5%) due to mushroom poisoning.”)

Habitat segregation between brown bears and gray wolves in a human‐dominated landscape. Milleret C, Ordiz A, Chapron G, Andreassen HP, Kindberg J, Månsson J, Tallian A, Wabakken P, Wikenros C, Zimmermann B, Swenson JE. Ecology and evolution. 2018 Dec


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.

Current status, distribution, and conservation of brown bear (Ursidae) and wild canids (gray wolf, golden jackal, and red fox; Canidae) in Turkey. Ambarli, H., Erturk, A. and Soyumert, A., 2016

Patterns in the use of rub trees by the Eurasian Brown Bear. Tattoni C, Bragalanti N, Groff C, Rovero F.Hystrix, the Italian Journal of Mammalogy. 2015 Dec

Wolves, people, and brown bears influence the expansion of the recolonizing wolf population in Scandinavia. Ordiz A, Milleret C, Kindberg J, Månsson J, Wabakken P, Swenson JE, Sand H. Ecosphere. 2015 Dec;

Brown bear circadian behavior reveals human environmental encroachment. Ordiz A, Kindberg J, Sæbø S, Swenson JE, Støen OG. Biological Conservation. 2014 May

Sheep and wolves: Is the occurrence of large predators a limiting factor for sheep grazing in the Czech Carpathians?. Kovařík, Petr, Miroslav Kutal, and Ivo Machar. Journal for nature conservation 22, no. 5 2014

Brown bear (Ursus arctos) phylogeography in northern Eurasia (Doctoral dissertation). Keis, M., 2013.

Brown bear (Ursus arctos) population structure, demographic processes and variations in diet in northern Eurasia (Doctoral dissertation). Tammeleht, E., 2011.

Brown bear conservation and the ghost of persecution past. Zedrosser A, Steyaert SM, Gossow H, Swenson JE.Biological Conservation. 2011 Sep

*WI Notes – Engen S, Lande R, Sæther BE. Evolutionary consequences of nonselective harvesting in density-dependent populations. The American Naturalist. 2014 Dec

Connectivity and population subdivision at the fringe of a large brown bear (Ursus arctos) population in North Western Europe. Kopatz A, Eiken HG, Hagen SB, Ruokonen M, Esparza-Salas R, Schregel J, Kojola I, Smith ME, Wartiainen I, Aspholm PE, Wikan S.Conservation Genetics. 2012 Jun

Knowledge and perceptions of Macedonian hunters and herders: the influence of species specific ecology of bears, wolves, and lynx. Lescureux N, Linnell JD. Human ecology. 2010 Jun

Genetic structure in large, continuous mammal populations: the example of brown bears in northwestern Eurasia. Tammeleht E, Remm J, Korsten M, Davison J, Tumanov I, Saveljev A, Männil P, Kojola I, Saarma U.Molecular ecology. 2010 Dec;

An investigation of public opinion about the three species of large carnivores in Slovakia: brown bear (Ursus arctos), wolf (Canis lupus) and lynx (Lynx lynx). Wechselberger M, Rigg R, Beťková S, Wechselberger M, Rigg R, Beťková S. Slovak Wildlife Society, Liptovský Hrádok, Slovakia. x. 2005

Status and management of brown bears in Turkey. Can ÖE, Togan İ.Ursus. 2004 Jan

Brown bear-livestock conflicts in a bear conservation zone in Norway: are cattle a good alternative to sheep?. Zimmermann B, Wabakken P, Dötterer M.Ursus. 2003 Jan

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