Vocal ontogeney and structure of giant otter pups in the hydrographic basin Tocantins-Araguaia
Giant otter, vocal repertoire, ontogeny, cubs and acoustic communication.
One of the foundations that structures and keeps cohesive animal societies is communication. The giant otter is a social animal that maintains group cohesion using vocal communication. Groups of giant otters defend territories along water bodies using acoustic and chemical signals. There is evidence of the existence of the vocal signature and individual recognition for the species. However, the vocal ontogeny of the giant otter remains poorly understood as well as the variation in the structure of the vocal repertoire. This work aims to investigate the vocal behavior of giant otter cubs, seeking to explore ontogenetic and functional issues in the Tocantins-Araguaia watershed (Cantão State Park), Tocantins state, Brazil. We recorded the sounds with a directional microphone from a minimum distance of 10m and a maximum of 50m and increased the sample using a Song Meter SM3 recorder at the entrance of the sighs of the giant otter burrows and five camera traps. We carried out 28 campaigns, and the campaigns lasted an average of 7 days, with an average of 12 hours in the field per day, totaling 2,688 hours of effort in the field. Otters are highly vocal from birth. Otter pups follow sequences of moans and yelps that can be characteristic of immature calls. Here we present a review of the classification of 16 vocal types found for spider pups and we associate the vocal repertoire with the age stage of these free-living pups. We also present three new types of sound that have not yet been heard for young spider spiders. Some vocal types such as: Cub call, Growl, Scream and Coo call appear in the first stage of life and remain until adulthood. Characteristically, how changes in the development of child production since birth (ontogeny) can bring information about the physiological and social factors that can influence such changes. In addition, this characterization is an important tool for preparing management plans in the natural environment, as well as helping to guide human activities involving the species, such as ecotourism.