Honda, T.; Tominaga, H.; Shimizu, A.

There are few effective methods to mitigate the economic or health-related disadvantages caused by birds. Traditional countermeasures employing sound and light have been utilized for mitigating crop damage, but their efficacy is insufficient, and human-avian conflicts persist. This study explores a fundamentally different approach to resolving these conflicts. Flashing lights that alternate between red and blue are known to stimulate the human brain and can potentially cause photosensitive epilepsy in one in 100,000 people, though very rarely. A 15 Hz flashing stimulus is known to elicit a significant response in humans; however, the optimal flashing pattern for birds remained unclear. We investigated the effect of different flickering patterns, specifically 12.5, 15, and 20 Hz, on crows when illuminated from a distance within 200 meters. The flashlight used was a long-range model and the Light Emitting Diodes (LEDs) consumed about 9 watts of power. The power was supplied by 21700 type lithium-ion batteries. Using a long-range flashlight during daylight, we determined that a 15 Hz flashing stimulus was most effective. This finding suggests that the most intense stimulus identified in human physiology can be equally effective when applied to birds. Survival analysis estimated that by projecting this pattern from a distance of 100 meters, crows fled within 8.1 seconds. Unlike traditional bird damage control techniques that rely on neophobia, this study utilizes physiological aversion. In this regard, our approach is fundamentally different from traditional techniques. The method of using flashing light to stimulate the brain, rather than the eyes, is based on insights from human medical and physiological studies. These findings elucidate the principle of a novel aversive stimulus using flashing light, which holds potential for widespread application in mitigating bird-related issues.