Comparison of Aerial Thermal Infrared Imagery and Helicopter Surveys of Bison (Bison bison) in Grand Canyon National Park, USA

Helicopter surveys outperform aerial thermal infrared (TIR) imagery for estimating bison populations in dense canopy cover areas, offering more accurate results at a fraction of the cost. A study comparing TIR and helicopter surveys on the Powell Plateau in Grand Canyon National Park found that TIR surveys detected fewer bison (101 to 127 individuals) and were 367% more expensive than helicopter surveys. The TIR estimate was also 18.8% lower than a larger dataset of helicopter detections, while the helicopter survey was only 9.3% lower. Despite limitations, this research suggests that current methods for bison abundance estimation in such environments favor helicopters due to their balance of accuracy and cost-effectiveness. Further investigation is needed to assess these techniques in more open landscapes.

Hennig, J. D., Schoenecker, K. A., Terwilliger, M. L. N., Holm, G. W., & Laake, J. L. (2021). Comparison of Aerial Thermal Infrared Imagery and Helicopter Surveys of Bison (Bison bison) in Grand Canyon National Park, USA. Sensors, 21(15), 5087. https://doi.org/10.3390/s21155087