Identification of dolphin schools by bioacoustical unique features

Long‐term acoustical observations conducted on bottle‐nosed dolphins (Tursiups truncatus ponticus) in the State Oceanarium of Ukraine as well as in the open sea revealed the existence of school specific acoustic features. It was found that each dolphin school uses a unique set of whistle contours in conjunction with a preferable frequency band and certain time characteristics. If the latter two characteristics somewhat vary according to particular surrounding and behavioral situations, the composition of normalized whistle contours stays stable. Each single whistle can be described by a set of polynomial coefficients characterizing its shape. Referring to the whole set of whistles emitted, a diagram of signal preferences can be built. Several samples will be presented to demonstrate that such diagrams represent acoustical portraits unique for every dolphin school. Based on those analyses, the development of a system for passive automatic monitoring of dolphin abundance and migration activity is in progres...