Chelonia PODs have revolutionised the way we study cetaceans in the wild. These fully automated passive acoustic monitoring instruments detect porpoises, dolphins and other toothed whales (except s***m whales) by recognising the trains of echo-location sounds they produce to detect their prey, orientate and interact.
Standard PODs can be deployed to at least 100 metres, while the deep sea version is designed for deployments to at least 2 km.
Over 3600 PODs have been deployed worldwide.
The C-POD design aims to achieve, at low cost:
Fast results from fully automated detection processes
Very low false positive rates
High sensitivity
Precise calibration
Long running times
Extreme robustness
To achieve these objectives the design is fully integrated from the mechanical engineering of the hardware through to the delivery of statistics-ready results from the software.
Deployment environments
PODs are in use in a wide range of environments, from the Arctic to the Amazon:
"Chelonia Ltd has, through the development of the T-POD and the successor the C-POD, created a whole new field of conservation research. Through the deployment of non-invasive PODs, data on Odontocete presence and echolocation characteristics now give new insights on animal behaviour and ecology and also make it possible to estimate absolute abundance even in low-density populations." Mats Amundin, International coordinator of SAMBAH Read more>>
Advantages of using PODs over WAV file loggers
The C-POD has made some previously inaccessible monitoring problems feasible:
The SAMBAH project, assessing whether the Baltic Sea harbour porpoise was still in existence and where it was, tackled the challenge of monitoring a species at very low density. That required a very low false positive rate from an automated classifier. Using a sequential process of click characterisation, train detection and classification, and then an encounter classifier developed for the Baltic Sea. The false positive rate was reduced to less than 1 false positive second per year of logging.
The Vaquita monitoring project combined the challenges of monitoring a small population in an acoustically adverse environment, i.e. one with clicks resembling porpoise clicks coming from multiple sources.
From these and other studies we have learned that the crucial step required to get very high performance automated detection is to develop the best possible set of train coherence metrics that can be used to reject false claims.
If you are considering a wave file logger, read further (PDF) to see the advantages of using PODs.
Full support
Email and telephone support is included with all instruments. You are welcome to contact us for help with any aspect of project planning or implementation.
