A Scientific, Non-Invasive Solution to Human–Bear Conflicts

I. Intensified global environmental changes have led to frequent human-bear conflicts.
In recent years, the trend of global climate change has intensified, with frequent occurrences of extreme heat and torrential rains, severely damaging the natural habitats and food sources of bears. At the same time, human activities continue to expand natural areas, with deforestation and land reclamation further shrinking the living space of bear populations. Facing food scarcity, bears are forced to cross the " human-bear boundary," actively entering human settlements, rummaging through garbage cans, and breaking homes or farmland in search of food. This phenomenon not only causes crop losses and property damage but has also led to numerous tragic incidents of bears injuring or even killing people. From rural North America to mountainous regions of Asia, the balance of human-bear coexistence has been severely disrupted, urgently requiring safe and effective solutions to alleviate the crisis.

Fig. 1 Bears have appeared in crowded cities

2. Traditional bear deterrent devices have limited effectiveness and carry the risk of a bear attack
Faced with the growing threat of bear infestations, common bear deterrent devices on the market often fall short of practical field requirements and even pose hidden risks. For example, passive warning devices like bear bells, with their constant, regular ringing, can easily lead bears to "habituate."  They gradually come to believe the sound is harmless and dismiss it as background noise. While this may provide a short-term warning effect, long-term use eliminates its repelling effect. Some products that simulate the calls of natural enemies present serious behavioral misjudgments. For species like adult brown bears and polar bears, which have few natural predators in their ecosystems, these calls pose no threat and may even mislead bears thinking they are looking for food, prompting them to approach. Furthermore, some stimulant devices, such as high-intensity flashlights, can, if used improperly (for example, by shining directly a bear's eyes at close range), make the bear feel threatened, triggering its defensive and aggressive instincts and exacerbating the danger.

III. Focusing on the bear crisis in Japan, developing a non-invasive and humane, portable bear deterrent device.
Bear-related injuries and fatalities have occurred in Japan, extending from mountain villages to the outskirts of towns. The frequency and aggressiveness of bear sightings have increased significantly, creating a pressing need for safe bear deterrent tools. In response to this situation, Chi Fung Electronics has focused on developing a portable electronic bear deterrent. Unlike traditional products, which can be ineffective or even irritate bears, this device is designed with "non-invasive and humane, and non-irritating" as its core principle. Through scientific sensory stimulation, it induces bears to engage in an "approach-avoidance" response (actively moving away) rather than a "defense" response (passively attacking). This device protects humans while also preventing permanent harm to bears, balancing practicality with ecological ethics.

Core Technology Analysis: Precision Circuitry and Acoustic Design for Efficient Bear Repelling
Zhifeng Electronics ' "Portable Electronic Bear Repeller " stems from its repeatedly validated technical architecture, which can be divided four main components:
1. Power Supply and Signal Generation: Powered by a portable battery, it is convenient for users to carry with them and deal with emergencies outdoors. It generates a dedicated bear-repelling frequency of 6KHZ~15KHZ through an IC oscillation circuit. This frequency band has been verified by animal behavior and not only covers the auditory sensitive area of bears, but is also subdivided the "core deterrence band" and the "close-range impact band". Among them, 2KHZ~8KHZ belongs to the " human-bear common hearing area", which users can hear clearly, making it easy to confirm the activation status of the device and alert their companions; 10KHZ~15KHZ is the "high-frequency auxiliary band". Human hearing is weak, but bears are extremely sensitive to it and it can form a "nerve stimulation shock wave" within 20 meters.
2. Signal amplification and conversion: The generated frequency signal is amplified by a boost circuit and then drives a piezoelectric buzzer to convert the electrical signal an acoustic signal.
3. Acoustic cavity resonance: Through a professionally designed acoustic cavity, sound waves are resonated and amplified, significantly increasing the sound pressure level (reaching up to 120 dB), ensuring that high-frequency sound waves can be transmitted to a greater distance, providing an effective warning to bears in advance.
4. Optimized operation logic: The "one-click emergency" design is adopted to avoid users missing the opportunity due to complicated operation in emergencies, while ensuring the "unpredictability" of the sound to prevent the bear from developing a habitual response.

Fig.  2 Block diagram of the circuit system

5. Comparison with Traditional Products: Avoiding Risks and Achieving Safe Bear Repellent
Compared to the shortcomings of traditional bear-repelling devices, Kingstate's "Portable Electronic Bear Repeller " fundamentally solves the two core problems of "ineffectiveness" and "provoking":
- To address the "ineffectiveness" issue: Abandoning the fixed frequency and regular sound design, we adopted variable frequency bands of 2~8KHZ & 10~15KHZ and sudden sound waves to prevent bears from developing habits; at the same time, we amplified the sound pressure through the acoustic cavity to ensure long-distance warning effect.
- Regarding the issue of "provoking": Instead of using sounds that are prone to misjudgment, such as simulated predator calls or bear roars, we use "unnatural chaotic sounds" as the core (such as a combination of high-frequency electronic noise and metallic scraping sounds) to take advantage of the bear's "novelty phobia" (instinctive avoidance of the unknown) to guide it to leave voluntarily, thus eliminating the risk of attack from a behavioral perspective.

Fig. 3. Bear Repellent Product Appearance

6. Deepen animal behavior research to ensure product effectiveness
To ensure the "Portable Electronic Bear Repellent " is suitable for use with various bear species (such as the Formosan black bear, North American black bear, and brown bear), Chi Feng Electronics has invested significant resources in conducting in-depth behavioral research on various bear species, including their auditory sensitivity ranges, response patterns to sounds, and habituation cycles. They also thoroughly researched relevant literature and conducted in-depth analysis from three perspectives: behavioral effectiveness, sensory safety, and user risk management. For example, to address the potential risk of a 120dB sound pressure level, they incorporated a "strongly directional sound source" (sound waves are emitted only forward) the design, and included a clear warning in the user manual: "Keep away from ears when operating," ensuring user safety while maintaining product efficacy.

Fig. 4 Spectrum diagram of bear-driving tones

7. Kingstate: Focusing on electroacoustic R&D and providing customized solutions
As a veteran developer and manufacturer of electroacoustic products, Kingstate Electronics not only offers a mature standard product line of portable electronic bear deterrents, but also offers customized OEM/ODM solutions tailored to specific operational and environmental requirements. For example, we can adjust the frequency range to target specific bear species (e.g., optimizing high-frequency sensitivity for polar bears); add flash assist and waterproof and drop-resistant features based on specific usage scenarios; and even customize chaotic sound waves with unique tones to further enhance bear deterrent effectiveness. For further information on our products or customized solutions, please visit our official website or contact us at info@kingstate.com.tw. We will provide detailed technical information and one-on-one consultation.