a) Seed dispersal

The effects of the digestive process by bears on germinability and germination rate of fleshy fruits were measured in controlled experiments. Fruits from 11 species: Prunus avium , Prunus spinosa, Sambucus nigra, Rosa sp., Rubus fruticosa, Malus sylvestris, Viburnum opulus, Crataegus monogyna, Vaccinium myrtillus, Sorbus aucuparia, Frangula alnus, with seeds of different size, were collected in the field during the ripening season, given to 3 captive bears and afterwards, the seeds recovered from the faeces. For each species, we planted 100 fruits with the pulp (field treatment), 500 seeds extracted from fresh fruits (control treatment) and 500 seeds recovered from bear scats (bear treatment).

Fleshy fruits are extremely important in the diet of brown bears and consumed in huge quantities. The germination experiment showed that seeds from 7( out of 11) species germinated better after bear than control or field treatment, seeds of one species germinated better after in the control treatment  and 2 species did not germinate in the first year of experiment. Preliminary results indicate an important role of brown bears as seed dispersers in temperate biomes and in the dynamics of some plant species

b) Foraging ecology

The brown bear is a tropic generalist with a very diverse diet and complex nutritional requirements, which are influenced by many environmental and individual factors. In the age of alteration in its habitat, namely the climate warming and abundance of artificial food resources, the trophic ecology of the species is undergoing serious changes on the population and individual scale. One of the symptoms of this phenomenon is the winter activity and the intensive use of ungulate bait by some individuals. The goal of this study is to investigate some of the brown bear’s feeding habits from the individual and population point of view, to evaluate of the role of artificial food sources in the trophic ecology of the species, and to make an attempt to predict the possible impact of global changes on its biology.

In particular, we aim at:
1) assessing the impact of individual factors as well as the spatial and temporal variation in food abundance on the diet of brown bear,
2) evaluating the role of seasonal and intra-individual variance in bear diet in shaping the time budget, home range size and movement patterns,
3) investigating the role of anthropogenic food sources in the ecology of brown bear, including the efficiency of use of this food,
4) studying the winter ecology in the individuals which do not hibernate and trying to assess the possible consequences of the global warming for this species.

c) Supplementary feeding and parasites

Supplementary feeding of wild ungulates is a widespread practice in North America and Europe and significantly important in Poland. Despite the impressive scale of supplementary feeding, understanding of the ecological effects of these massive subsidies is still little and the real benefits of this practice on ungulate populations remain questioned. One of the potentially most important indirect effects of supplementary feeding is the increased risk of pathogen transmission. The increasing emergence of infectious diseases (mostly zoonoses associated with wildlife) makes this issue of severe concern worldwide. In some areas, supplementary feeding has already been pointed as an important factor in the transmission of re-emerging diseases, such as bovine brucellosis or bovine tuberculosis. The large number of animals which congregate at the feeding places, the increased rate of contact between them, and the wide range of potential host species of some pathogens make us to hypothesize that this management practice may play a key role in pathogen occurrence and transmission, also in Poland. The general goal of this project is to evaluate the impact of feeding practices on pathogen prevalence and transmission in the animal community of the Bieszczady mountains at population and individual level. We will focus on the main consumers, that’s is, three main ungulate species (the red deer Cervus elaphus, roe deer Capreoulus capreolus and wild boar Sus scrofa), and the brown bear Ursus arctos, a non-target species, but frequent user of baiting sites.