Den Entry Behavior in Scandinavian Brown Bears: Implications for Preventing Human Injuries

Area of Science:

• Wildlife Ecology
• Behavioral Ecology
• Mammalogy

Background:

• Human-brown bear encounters causing injury and fatalities often occur near dens during den entry in autumn.
• Understanding bear behavior during den entry is crucial for mitigating human-bear conflict.

Purpose of the Study:

• Determine brown bear den entry timing and predictors.
• Document associated behaviors and activity patterns.
• Explain increased human injury risk during this period.

Main Methods:

• Analysis of global positioning system (GPS) location and activity data from brown bears in south-central Sweden.
• Application of generalized linear mixed models, statistical process control, and activity analyses.
• Investigation of factors influencing den entry timing and behavior.

Main Results:

• Brown bears entered dens between October 6 and December 1, with timing varying by reproductive status, age, and year.
• Bears exhibited varied activity reduction patterns before or after den arrival.
• Higher den abandonment rates were observed due to disturbance, especially in males and first-time den visitors.

Conclusions:

• Brown bear den entry timing is highly variable and unpredictable, making restrictions on human activities impractical for risk reduction.
• Educating the public, particularly hunters, about bear behavior during den entry is essential.
• Increased human injury risk may stem from various behavioral and physiological changes, not solely aggressive den defense.