نبذة مختصرة : International audience ; Coastal odontocetes are resident species which are highly threatened by human activities such as fishing, harbour development or fish farms. In Southern Chile, four species of NBHF (Narrow Band High Frequency) dolphins and porpoise share this threat, in a coastal area that is of growing economical interest. Passive acoustic monitoring is an interesting tool to assess the presence of these species. However, their acoustic emission have been little studied and there is actually no means of acoustically classify the different species. We argue that actual parameters used to characterize the NBHF clicks are not precise enough and propose a new method of measuring the frequency and duration of a click, by fitting a mathematical function (a Gabor wavelet) to the click. In this work, we show some important biasses of classical NBHF clicks parameters, and discuss the interest of a Gabor wavelet model. Our method is applied on two dataset with two distinct species in southern Chile : the Peale dolphin (Lagenorhynchus australis) and the Chilean dolphin (Cephalorhynchus eutropia). The results show the striking inter-specific similarity of NBHF clicks, and point towards possible method to separate them.
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