SAMBAH - Static Acoustic Monitoring of the Baltic Sea Harbour Porpoise - is an international project involving all EU countries around the Baltic Sea, that runs since 2010 within the European LIFE+ nature programme.

The main objective of the project is to support the preservation of the harbour porpoise in the Baltic Sea through scientific data and research. For this purpose approximately 300 porpoise click detectors are deployed in around the Baltic Sea, which collect data about the density, frequency and distribution of harbour porpoises until May 2013. Furthermore the preferred habitats of porpoises should be found to identify areas with impact to porpoise population due to human interaction.

Why acoustic monitoring?

The harbor porpoise sends out very short pulses of high frequency sound in swimming direction for orientation, navigation, communication and to capture prey. If these sound waves hit an object, they come back as an echo. Porpoises use their biosonar almost every time. Therefore, an acoustic monitoring with automatic devices for recording the echolocation sounds of mobile animals is very efficient. The so-called click detectors record the sound of porpoises.

Despite modern technology, it is not that easy to determine the exact number of animals. The mere fact that the sound beam is directed very locally and the detectors have only a range of about 200 meters makes difficulties.

Further reading

Click detectors
The SAMBAH click detectors
(Source: DMM)

Click detectors
Click detectors before deployment
in the Baltic Sea.
(Source: DMM)