C-POD (Cetacean Acoustic Hydrophone Network) | Flanders Marine Institute

Flanders Marine Institute

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C-POD (Cetacean Acoustic Hydrophone Network)

C-PODs are hydrophones that passively monitor acoustics in the water. They are used to record the presence of toothed cetaceans (Odontoceti), in a periphery of 200-400 meters from the device location. With high-quality data, the presence of harbor porpoises and dolphins are registered.
There are, anno 2017, eight C-PODs forming a passive acoustic monitoring network that registers the presence of odontocetes in the Belgian part of the North Sea. This network, an initiative by the LifeWatch project, has been under continuous development since 2014.


How do C-PODs work?

A C-POD can be used in two ways: it can be deployed from a moving research vessel, or it can be deployed at sea as a stand-alone stationary device. It needs attachment to the sea bottom or surface (buoys, shipwrecks, etc.)

C-PODs log all acoustics within the range of 20-160 kHz, after which they detect certain sequences of acoustic clicks (or ‘trains’), typical of cetaceans. These trains can then be further analysed. Raw data is stored on memory cards and due to the long battery lifetime, data of three months can be obtained.
An onshore, midshore and offshore gradient of C-PODs, attached to buoys and/or to the bottom, is established in the Belgian part of the North Sea.

What are C-PODs used for?

  • To detect the presence of harbour porpoises and dolphins
  • To assess the seasonal presence and distribution of harbour porpoises in the Belgian part of the North Sea

Technical details

VLIZ uses C-PODs developed by Chelonia Ltd. and the corresponding software

  • polypropylene housing
  • functions at maximum depths of 100 m
  • dimensions: 670 mm length, 90 mm diameter, 3.5 kg weight (buoyant)
  • hydrophonic range: 20-160 kHz, 400 m detection range for porpoises, > 1 km for dolphins
  • for more information: click here

How to access C-POD data?

C-PODs cannot be borrowed but the data is freely available for all scientists. Contact data@vliz.be

Use and conditions

Note: if you use C-POD data provided by VLIZ as a scientist, please refer to it in your publication(s) as: "This work was supported by data & infrastructure provided by the Flanders Marine Institute (VLIZ) as part of the Flemish contribution to LifeWatch."