125
state it is commonly sighted near the coast (Ott and Danilewicz 1996; Meirelles
et al. 2009; Lodi and Hetzel 2012; Bastida et al. 2007) (Fig. 5.10).
As the majority of the delphinids species, the rough-toothed dolphin produces
tonal (whistles) and pulsed sounds (echolocation clicks and burst pulses – broadband emissions) (Tyack and Clark 2000; Oswald et al. 2003, 2007; Rankin et al.
2008a, 2015; Hoelzel 2009; Baumann-Pickering et  al. 2010; Corrêa 2012; Lima
et al. 2012; Amorim et al. submitted) (Fig. 5.11). The acoustic signals produced by
this species have been discussed in the literature through different approaches such
as: acoustic repertoire characterization (Busnell and Dziedzic 1966; Watkins et al.
Fig. 5.10 Rough-toothed
dolphin photographed off
the Brazilian coast
(Reproduced with
permission of Pedro Fruet)
22
20
18
16
14
12
10
8
6
4
2
kHz
S 43:46.8 43:47
43:48
43:47.2 43:47.4 43:47.6 43:47.8
Fig. 5.11 Steno bredanensis acoustic signal presented in a spectrogram (Whistles and clicks,
respectively)
5 Marine Mammal Bioacustics Using Towed Array Systems in the Western South…