National and regional story (Slovenia) - A Bear’s tale

Bears' diet

The bear is an opportunistic omnivore, meaning that it eats anything that is available and easily accessible to it at a particular time. Most of the bear's diet is of plant origin. The most difficult period is spring, when winter stocks run out and the vegetation season has not yet begun. It is at this time that the bear may attack weakened biungulate game and, occasionally, livestock, particularly sheep and goats. From the beginning of the vegetation season until late autumn, bears enjoy feeding on grass and on the fruits of forest plants (common dogwood, hazel, strawberries, blueberries, blackberries). In the autumn, when they are collecting fat for hibernation, the fruits of forest trees (beech nuts, acorns, chestnuts, hazelnuts, other nuts) and fruit from orchard trees (pears, apples, plums) are an important part of their diet. For bears, protein-rich food includes insects (chiefly ants and their pupae) and carrion. Occasionally, bears will look for food close to human settlements (household waste and other food remains), which can bring them into conflict with human beings.

Part of the Analysis of Bears Taken from the Wild and Genetic-Molecular Research into the Bear Population in Slovenia (Kos et al, 2008) study was devoted to defining the brown bear's diet, with the aim of identifying its most important sources of nutrition. The contents of the digestive tracts of 128 bears taken from the wild between 2006 and 2008 were examined. The remains of food in the stomach and intestines were subjected to precise macroscopic and microscopic examination, and a precise taxonomic identification made (as far as was possible) of food of plant origin. Bears were found to feed most regularly on food of plant origin (forage, forest products, fruit), and less frequently on food of animal or anthropogenic origin (Figure 3).

Food of plant origin is present more or less equally through the whole year, while the frequency of the other two types of food fluctuates considerably (Figure 4). Food of anthropogenic origin is considerably more frequent in the spring and food of animal origin in the summer months.

It is the males that most frequently feed on food of anthropogenic origin, with the females favouring food of plant origin. Food of animal origin is equally represented across the two sexes. It is also noticeable that food of anthropogenic origin is frequently found in bears that have been culled. Research has confirmed the omnivorous and opportunistic nature of the feeding habits of the brown bear, which selects from a wide range of food. Bears adapt fairly quickly to a permanent source of food, whether a feed site or waste in the vicinity of human settlements, and they make regular visits to such areas.