Contribution to the distribution and habitat use of bottlenose dolphins off Brazil from aerial surveys

SUCUNZA, F.; DANILEWICZ, D; CREMER, M.; DENUNCIO, P; SECCHI, E.; ZERBINI, A; ANDRIOLO, A.; FERREIRA, E.

Rio Grande

Encuentro; II Encontro Internacional sobre pesquisa e conservacao de Tursiops spp.no Atlántico Sul Occidental; 2017

Universidade Federal do Rio Grande

In this working paper we provide new records of bottlenose dolphins obtained during 32 dedicated aerial surveys. Visual surveys were conducted between 2011 and 2014 in 33 coastal and pelagic waters off the Brazilian coast. We observed 39 groups of bottlenose 34 dolphins Tursiops truncatus during 19,627km of survey effort. New records of 35 bottlenose dolphin groups were provided for areas with low survey effort, and indicate 36 that the species is common in those areas. Our results also support a restricted coastal 37 distribution of bottlenose dolphins proposed for the Rio Grande do Sul coast. We also 38 added important records regarding the occurrence of bottlenose dolphins in pelagic 39 waters. Finally, this study reinforce the utility of aerial surveys to study bottlenose 40 dolphins in areas of logistical constraints such as open coastal areas and pelagic waters.