Authors: Ježek, Miloš; Silovský, Václav ;Faltusová, Monika;

Long-term tracking is one of the most important methods for studying animal behavior. Scientists are developing more sophisticated devices for tracking during the last decades, but continuously long-term tracking and detailed behavior description have not been possible yet. Here we take advantage of the emergence of biologging technologies to characterize the adaptive significance and biophysical mechanisms underlying analyses in free-roaming wild boar and red deer. We have designed biologging collars equipped with tri-axial accelerometer and magnetometer sensors and GPS tags. During the last 3 years, we tested these devices on 85 wild boar and 36 red deer. The average tracking period was 103 days (maximum 202) for wild boar and 203 days for red deer (maximum 413). Accelerometer data from a subset of individuals was synced with ground-truth video records to develop and test behavioral classifiers using machine learning techniques. Behavioral classifications were then time-synced with magnetometer and GPS for calculation of real path of the animal by dead-reckoning. A preliminary analysis based on these new technologies gives us detailed information about animals' lifestyles. Furthermore, the continued development of these technologies and techniques will offer new opportunities to investigate a range of important biological and ecological topics.