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5.5 Ecological Approaches of Bioacoustics Using Towed
Array
5.5.1 Acoustic Discrimination Between Species
The extensive use of Passive Acoustic Monitoring for detecting and monitoring
marine mammals has generated huge volumes of data (Mellinger and Barlow 2003).
Species identification from acoustic recordings of marine mammal vocalizations
can be challenging due to the high variability in many of the characteristics of
sounds that can be easily measured or extracted from spectrograms, both within
species and among species (e.g. Oswald et  al. 2003, 2004; Roch et  al. 2007;
Soldevilla et al. 2010; Baumann-Pickering et al. 2015).
The analysis of cetacean sounds to the species level is an important step in processing long-term passive acoustic recordings made in a marine environment
(Baumann-Pickering et al. 2010). Most of works on acoustic classification of odonFig. 5.22 Spectrograms of killer whale (A) high frequency whistle (HFW) (B) whistle contour,
(C) clicks and (D) calls recorded in the western South Atlantic Ocean
A. Andriolo et al.