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In the 1930s, the Scandinavian brown bear was close to extinction due to vigorous extermination programmes in Norway and Sweden. Increased protection of the brown bear in Scandinavia has resulted in the recovery of four subpopulations, which currently contain close to 1000 individuals. Effective conservation and management of the Scandinavian brown bear requires knowledge of the current levels of genetic diversity and gene flow among the four subpopulations. Earlier studies of mitochondrial DNA (mtDNA) diversity revealed extremely low levels of genetic variation, and population structure that grouped the three northern subpopulations in one genetic clade and the southernmost subpopulation in a second highly divergent clade. In this study, we extended the analysis of genetic diversity and gene flow in the Scandinavian brown bear using data from 19 nuclear DNA microsatellite loci. Results from the nuclear loci were strikingly different than the mtDNA results. Genetic diversity levels in the four subpopulations were equivalent to diversity levels in nonbottlenecked populations from North America, and significantly higher than levels in other bottlenecked and isolated brown bear populations. Gene flow levels between subpopulations ranged from low to moderate and were correlated with geographical distance. The substantial difference in results obtained using mtDNA and nuclear DNA markers stresses the importance of collecting data from both types of genetic markers before interpreting data and making recommendations for the conservation and management of natural populations. Based on the results from the mtDNA and nuclear DNA data sets, we propose one evolutionarily significant unit and four management units for the brown bear in Scandinavia.

The seasonal food habits of brown bears Ursus arctos were estimated based on the analysis of 266 scats in central Norway and Sweden. Free‐ranging domestic sheep Ovis aries were common in the Norwegian part of the study area, but were not found in the Swedish part. Correction factors were used to correct for differences in digestibility and nutritional value of different foods. Because correction factors for ungulates are difficult to estimate, the results should be interpreted with some caution. In terms of digestible energy, ungulates, mostly carrion, were the most important food in both areas during spring. During summer, ants, forbs, and ungulates (reindeer Rangifer tarandus and moose Alces alces) were the most important food items in the Swedish area, and sheep were most important in the Norwegian area. The autumn diet was dominated by berries in the Swedish area and sheep and berries in the Norwegian area. Among berries, crowberry Empetrum nigrum was the most important species, followed by bilberry Vaccinium myrtiUus in Sweden. The major difference between the Swedish and Norwegian areas was the large consumption of sheep in Norway, which provided protein and lipids, and was associated with a relatively reduced consumption of ants and forbs in summer and berries in the autumn. Based on different ingestion rates among the seasons, we estimated the relative contribution of major foods to total digestible energy. In the Swedish area, bears obtained 44–46 and 14–30% of their total annual energy from berries and ungulates, respectively. The remaining energy was obtained from insects (14–22%, mostly ants) and forbs and graminoids (12–18%, mostly blue sow thistle Cicerbita alpina). In Norway, bears obtained 65–87% of the energy from ungulates (mostly sheep), 6–17% from berries, 5–13% from insects, and 2–6% from forbs and graminoids. To gain weight prior to denning, brown bears in Norway selected lipid‐rich and easily obtainable sheep in summer and autumn. In Sweden, they relied on carbohydrate‐rich berries in autumn.

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Records of bountied brown bear s Ursus arctos in Norway and Sweden were analy sed to estimate population size in the mid-1800' s, and changes in popul ation size and distribution in relation to the bear management policies of both countries. In the mid-1800' s about 65% of the bears in Scand inav ia wer e in Norway (perhaps 3,100 in Norw ay and 1,650 in Sweden). Both countries tried to eliminate the bear in the 1800 ' s; Sweden was more effective. By the turn of the century, the numbers of bears were low in both countries. The lowest population level in the population remnants that have subsequently survived occurred around 1930 and was estimated at 130 bears. Sweden' s policy was changed at the turn of the century to save the bear from extin ction. This policy was success ful, and the population is now large and expanding. Norway did not change its policy and bear s were virtually eliminated by 1920-30. Since 1975, bear observations increa sed in Norway. Thi s coincided temporally with an abrupt increase in the Swedish bear population, and bears reappeared sooner in areas closer to the remnant Swedish population s. Both cond itions support our conclusion that the bear was virtually exterminated in Norway and suggest that bears observed now are primarily immigrants from Sweden , except for far northern Norw ay, whi ch was recolonised from Russia and Finland. Today , we estimate that the Scandinavian bear popul ation numbers about 700 , with about 2% in Norw ay (on aver age about 14 in Norway, 650 -700 in Sweden). Thi s is a dra stic reduction in the estimate of bear s in Norway, compared with earlier stud ies. The trend s in bear numbers responded to the policies in effect. The most effective measure s used in Scandinavia to con serve bears were those that reduced or eliminated the economic incentive for people to kill them . Our analy sis also sugges ts that population estim ates based on reports from observation s made by the general public can be greatly inflated.

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