Brown bears are omnivorous. Their diet depends on season and food availability but consists mainly of plants. The research on bear diet conducted in Slovakia showed that from spring to early summer they mainly ate green parts of plants while in late summer and autumn the share of fruit, mainly blueberries, raspberries and blackberries increased. Ants and insects of the Vespidae family became their additional source of food from early autumn.
Brown bears often forage in crops. The studies of bear diet in the Bieszczady region indicated that in spring their diet was dominated by grasses, herbs and ungulates while in summer by herbs and blueberries. In autumn bears mainly ate beechnuts and foraged in abandoned orchards eating apples, pears and cherries. The crops were a significant supplement to their diet there, especially in spring and autumn. Meat constituted only 1/3 of their diet, its share increasing from late autumn to early spring (Szczutkowska 2009, Bojarska et al. 2011).