Instituto Boto Cinza Guiana dolphin distribution between 2005-2007 in Sepetiba Bay, Brazil

Original provider:
Projeto Boto Cinza

Dataset credits:
Projeto Boto Cinza

Abstract:
Between August 2005 and July 2007, 376 Guiana dolphin (<i>Sotalia guianensis</i>) encounters were documented in Sepetiba Bay.
For the purpose of this study all dolphin sightings were classified as groups or aggregations. Groups (N = 268, x = 20, range =
1–90) consisted of dolphins in apparent association usually engaged in the same behaviour and moving in the same direction.
Aggregations (N = 108, x = 204, range = 100–450) consisted of temporal association of numerous groups gathered in an
area, totalling several hundred individuals usually engaged in the same behavior but not necessarily moving in the same
direction. Guiana dolphin groups and aggregations differed significantly in behavioral activity, spatial and temporal distribution
and age composition. Most aggregated dolphins were engaged in foraging/feeding activities and primarily located at
the interior of the bay, and also, aggregations were more likely recorded during morning hours and had more neonates and
calves present when compared to groups. The plotted global positioning system (GPS) records of aggregations formed two distinct clusters of distribution
within the bay, indicating potential areas where conservation strategies could be implemented.