Baleen whales produce strong and stereotyped songs which are often recorded by Ocean Bottom Seismometers (OBS). As they combine hydroacoustic and seismic sensors, these instruments provide a good opportunity to track the whales from their songs. This study aims at developing a long-range tracking method of baleen whales, based on methods previously developed for ship tracking (Trabattoni 2020). The main goals are: - to accurately estimate the distance of the source using the multipath propagation, and improve the usual detection range; - to estimate the source azimuth using the 3-components seismometer; - to combine the distance and azimuth information to rebuild the whale trajectory.