Method for localizing a marine mammal in an underwater environment implemented by a PAM system, corresponding device, computer program product and non-transitory computer-readable carrier medium

The invention relates to a technique for localizing a marine animal in an underwater environment implemented by a passive acoustic monitoring system, the passive acoustic monitoring system comprising a network of acoustic sensors adapted to carry out measurements of acoustic signals. The method comprises steps of: - obtaining (21), from the network of acoustic sensors, measured data of an acoustic signal emitted by a marine animal; - defining (22) a space of dimensional representation of the underwater environment discretized in a plurality of predefined cells, - for each cell of a predefined set of cells among said plurality, obtaining (23) an error defined as a value of a cost function for said cell, said cost function giving a deviation between: * at least some of said measured data and * corresponding theoretical data obtained by assuming that the marine animal is located in said cell, said errors obtained for the predefined set of cells enabling to obtain at least one piece of information about localization of the marine animal (25a-25e).