Brown bear denning habits in northeastern Türkiye

Abstract

Denning behavior is essential for species that must survive difficult seasonal conditions when food is scarce. In the first denning study conducted in Türkiye, we investigated the denning habits of brown bears in the evergreen Sarıkamış forest in the east of the country. Using the bear movement data of bears recorded by GPS between 2018 and 2023, we identified 43 winter dens and 12 day-beds (daily resting places) used by bears. This study revealed the existence of five winter dens with separate toilet chambers, a phenomenon not previously documented in the literature. These chambers were separated from the sleeping areas by rocks or in a tunnel cavity. Our results showed that most winter dens were located in rocky regions and cliffs (83 %), while 17 % were in foothills and non-rocky areas, excavated areas, or under tree roots. Males had occupied all the excavated dens, with one exception. Notably, the den entrances were narrower in the foothills. This discrepancy can be attributed to the relatively constant height of the caves, which does not differ significantly from natural caves in rocky and mountainous areas. The geographical orientation of the excavated winter dens, which mainly faced north, may also contribute to this difference. Our data on denning chronology highlighted significant differences in denning behavior between female and male bears, with females exhibiting longer denning durations. These findings contribute to our understanding of bear ecology and emphasize the importance of considering sex-specific behaviors in wildlife management and conservation efforts. Our findings highlight the potential threats that current and future human infrastructure development pose to the long-term viability of bears in an understudied region at the confluence of two global biodiversity hotspots.