Impacts of Tourism on Wild Elephant Behavior in a Protected Area: Thresholds for Sustainable Wildlife Viewing

Wildlife tourism can support conservation but also imposes stress on wildlife, particularly cognitively complex and social species like Asian elephants (<i>Elephas maximus</i>), highlighting the need for science-based management regulations. We assessed the behavioral responses of wild Asian elephants in Kuiburi National Park, Thailand, against varying levels of tourism pressure using scan and focal sampling over three years, including during park closures. We hypothesized that tourism pressure influences elephant behavioral responses, with the strength and nature of responses varying according to disturbance intensity, demographics, and environmental variables. Tourism pressure was measured at two scales: sighting tourism pressure (STP; number of people, vehicles, distance, and noise at each elephant sighting) and Daily Tourism Pressure (DTP; total daily tourists). Elevated numbers of vehicles, people, noise, and close distances significantly increased rates of stress-related, vigilance, and passive aggressive behaviors while reducing affiliative behavior and prompting retreat. The most consistently selected tourism-related predictors of behavior were number of vehicles, number of people, proximity to humans, and noise level, with affiliative behavior emerging as the most sensitive indicator of disturbance. Behavioral thresholds were identified for "ideal" and "acceptable" tourism conditions: > 100 m/125 m viewing distance, < 4/< 8 vehicles, < 10/< 21 people, and noise < 32/< 42 dB, beyond which negative behavioral responses increased significantly. Following park re-openings, elephant detections declined, especially for cow-calf groups, indicating increased avoidance and vulnerability to tourism of socially cohesive groups. These results support evidence-based regulations for wildlife tourism, including the use of thresholds for management such as buffer zones, quiet viewing protocols, daily and sighting vehicle and visitor caps, guide training, and adaptive seasonal closures. Integrating empirically derived behavioral thresholds into protected area and national policies provides a scalable and transferable model to reduce disturbance, improve animal welfare, and promote ethical and sustainable elephant tourism in Thailand and beyond.