46 visually observing the study area. The received data of both PODs were analyzed and compared to each other as well as to the broad-band recording analyzed in AVISOFT (Saslab). This poster shows the results of the recordings from a visually confirmed harbour porpoise encounter. The porpoise’s echolocation sequences were recorded successfully on all three systems and could be assigned to each other. In the T-POD.exe software, these sequences were identified by the algorithm as high and low probability cetacean click trains as well as very doubtful trains. A comparable algorithm for C-PODs is not yet available, but the detected sequence was visually confirmed as being of porpoise origin. Parameters obtained by the different recording systems for each click such as the duration of clicks and their frequency characteristics were compared. This study shows that both POD models are valuable tools for registering harbour porpoises. Furthermore, the CPOD provides additional information to validate porpoise registrations.