We report and describe unusual behaviors of fighting and whistling in a species considered to be shy and calm. Baird’s tapir is the largest of all Neotropical mammals and lives in dense well conserved tropical forest of America. For ten years, in the Calakmul Biosphere Reserve of Southern Mexico, we have monitored tapir population in ponds locally named aguadas that serve as social arenas for the species. Recently, we obtained 97 video records in which some tapirs get involved in serious fights and other behaviors related probably to courtship, including several types of whistles. We described what we recorded and interpret these behaviors when possible. These rare behaviors in tapir can explain several of the wounds and scars that many adults of the population show and help us to understand better the social dynamics of this shy and endangered species of neotropical ungulate. We hope that all this information can help its conservation.