The Diet of the Brown Bear (Ursus arctos) in the Central Forest Nature Reserve (West-European Russia), Based on Scat Analysis Data

Resumo

Abstract—The diet of the brown bear (Ursus arctos) is described for the territory of the southern taiga subzone illustrated by the example of the Central Forest Nature Reserve (West-European Russia) and the protection zone surrounding it. Based on an analysis of 474 scat samples, we established the most commonly consumed food items and food groups and determined their proportions, nutritional value, and importance in the total diet of the species using basic techniques widely adopted abroad for processing the data. The investigation revealed 26 food items, including 18 plant (FO = 97.9%) and eight animal items (9.1%). Correction factors were used for each diet item. Food habits were assessed separately for the spring, summer, summer–autumn, and autumn periods. The frequency of scat occurrence per 10 km averaged 1.30. The most important in the bears’ diet were apples (EDEC = 31.1%), hazelnuts (19.1%), oats (12.5%), blueberries (6.8%), and forbs (4.3%). Mammal food had a certain value (EDEC = 11.1%), but mostly in the spring season. The width of the trophic niche decreased from spring to autumn. The diet composition varied greatly throughout the year, except for a hyperphagia period, which included summer and autumn. The territory of the moderately disturbed protection zone was more attractive to bears than the intact area of the reserve. Overall, scat analysis in the study area adequately reflects the basic preferences of the species, but underestimates the values of individual food groups, primarily insects, overestimates the value of apples, and poorly characterizes the feeding habits in the first half of the year.