Scopin A.E., Lipatnikova S.V., Polushkin A.A. 2025. Scat composition as an indicator of brown bear diet quality on Iturup Island // Russian J. Theriol. Vol.24. No.2. P.118–132 [in English].
Alexey E. Scopin [scopin@bk.ru], Svetlana V. Lipatnikova [lipatnikova_sveta@mail.ru], Anton A. Polushkin [toni.polushkin@mail.ru], Department of Wildlife Resources and Animal Ecology, Prof. B.M. Zhitkov Russian Research Institute of Game Management and Fur Farming, 79 Preobrazhenskaya str., Kirov 610000, Russia.
doi: 10.15298/rusjtheriol.24.2.05
ABSTRACT. The results of fractional and chemical analysis of adult brown bear scats are presented. Feces were collected on Iturup Island in summer. The bulk of the bear scats was represented by large-sized fractions of fecal particles, that indicates poor food processing and inefficient digestibility of the consumed food. The coefficient of variation (CV) of occurrence of particle fractions in different scat samples varied within 66–152%. The average dMean value of fecal particles for brown bear scats on Iturup Island is 8.34 mm. The highest dMean (4.6–20.9 mm; 10.4 mm on average) were found in the scat samples containing algae, while the lowest (1.2–6.5 mm; 4.3 mm on average) were detected in the samples containing mainly fruits and seeds. Due to the high variability of the mass of different fecal particle fractions, there are tricky statistically to discern the pooled scat samples between the bears roaming on the coasts and in the inland mountainous areas. Among the macronutrients, crude fiber was the main component of the bear scat (23.5% on average, maximum — up to 55.8%). The protein ratio in the scats was from 0.12 to 0.94 (0.41 on average). The fecal samples differed greatly in fat content (up to 18 times). The scat composition of bears consuming high-lipid plant seeds or fish carrion contrasts sharply with the scats which contain only the vegetative parts of plants. No significant statistical differences were found between the mass of separate fecal particle fractions and the nutrient composition of feces. Scat composition can be used as an indicator of brown bear nutrient status and to assess the quality of habitats.
KEY WORDS: Ursus arctos, scat analysis, fecal particles, macronutrients, Iturup island.