Behaviour 2019
An Examination of the “Squeal” Vocal in Newborn N. American River Otter Pups.  
Carla Almonte. Ronin Institute, Norwalk, CT, United States

In a previous study (Almonte, 2014) the unique “whistle” call type present only in newborn pups was introduced. For this study, it has been renamed “squeal” to more accurately describe the call type and this study is an examination of that “squeal”. The results to date suggest that the squeal is aurally and visually distinct from other call types present in N. American river otter vocal repertoires. Otter pups were observed in a controlled environment from birth until two weeks old using an infrared surveillance system with audio capability. To date, 5 hours have been reviewed and a quantitative analysis of 238 calls has been conducted for acoustic parameters that measured duration, frequencies and interpulse intervals. Additionally, visual sonograms were obtained for each call. The preliminary results suggest the whine and chirp are the predominate vocals used by newborn pups. But the squeal is often exhibited when pups are nuzzled by their mother and when the mother is self-grooming and not engaging with the pups. Furthermore, the squeal sonogram is distinctively different from the whine and the chirp however, shares similarities in appearance with both call types.