Open AccessIntegrative bioacoustics discrimination of eight delphinid species in the western South Atlantic Ocean
Author(s) -
Thiago Orion Simões Amorim,
Franciele Rezende de Castro,
Juliana Rodrigues Moron,
Bruna Ribeiro Duque,
Juliana C. Di Tullio,
Eduardo R. Secchi,
Artur Andriolo
Publication year - 2019
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0217977
Subject(s) - bioacoustics , delphinus delphis , discriminant function analysis , human echolocation , bottlenose dolphin , linear discriminant analysis , biology , beaked whale , sonar , leucas , pattern recognition (psychology) , zoology , artificial intelligence , whale , computer science , ecology , fishery , machine learning , telecommunications , neuroscience
This study presents an integrative bioacoustics approach to discriminate eight species of odontocetes found on the outer continental shelf and slope of the western South Atlantic Ocean. Spinner, Atlantic spotted, rough-toothed, Risso’s, bottlenose, short-beaked common dolphins, killer and long-finned pilot whales were visually confirmed during recordings with a 3-element omnidirectional hydrophone array. Spectral and time parameters of whistles and echolocation clicks were used in a discriminant function analysis and a classification tree model. As a first step, whistles and clicks were analysed separately; a further analysis consisted of both vocalisations jointly classified. All species showed species-specific properties in their vocalisations. Whistles had greater misclassification rates when compared to clicks. The correct classification was enhanced by the joint step, given the 5.8% error in the discriminant function analysis and a misclassification rate of 18.8% in the tree model. In addition, Receiver Operating Characteristic curves resulting from the tree algorithm analysis exhibited better model efficiency for all species in the joint classification. These findings on acoustical discrimination of such abundant and cosmopolitan species contribute to delphinid classification systems.