Passive Aquatic Listener: A state-of-art system employed in Atmospheric, Oceanic and Biological Sciences in the Marine Environment Prof. E. N. Anagnostou, Dr. M. N. Anagnostou & Prof. Jeff Nystuen Hellenic Center for Marine Research, Institute of Inland Waters

Applications Geophysical/Geological applications: wind speed, rainfall, drop size distribution, cold/warm seepage gas bubbles, volcanic eruption, seismic activities, ice-breaking, etc. Biological monitoring for sound-producing animal populations (bioacoustics) Anthropogenic activities

Technological overview of PAL Relatively simple measurement Robust technology (hydrophones) Moorings, cabled networks, floats/drifters

Technological Overview of PAL Components Low-noise broadband hydrophone 100 Hz – 50,000 Hz TT8 micro-computer processor with 100 kHz A/D sampler 2 Gb memory card 65 amp-hour battery package Electronic filter and 2-stage amplifier

Sea Level m 2000m (d 1 ) d 1 d 2 50m (d 2 ) Listening Area of PAL – Spatial Averaging The expectation is that the listening area for each hydrophone is a function of the depth of the hydrophone. Roughly half of the energy arriving at the hydrophone comes from an listening area with radius equal to the depth of the hydrophone and 90% of the energy from an area with radius equal to 3 times the depth.

Sampling/Recording modes Pre-configured Wake-up/Sleep modes Record short time series (4.5 s at 100 kHz) Examine time series Fourier transform (0-50 kHz) Store spectra, not the time series* Identify sound source Quantify source Return to “sleep” mode Two Modes of Recording Spectral time series at intervals determined by the sound source Short 100 kHz time series (4.5 sec) of targeted sound source

PAL/Deployment modes m Sal, Temp, 500m PAL(Passive Acoustic Listener) Pressure sensor Sal, Temp Meteo, curents, waves PYLOS

PAL/Poseidon system Analysis of PAL’s data after retrieving the instrument from the Pylos Buoy

PAL/Poseidon system Comparison of PAL’s wind speed retrievals with the Buoy’s surface anemometer showing high correlations and small biases

PAL/Poseidon system

Sound intensity peaks, of dolphin or whale clicks and whistle; the pressure time series collected by PAL on 30 November 2008 at Pylos’ site. The lower panel shows a spectral analysis from 0 – 20 kHz as a function of time

Paul R. Houser, November 7, 2005, Page 12 Poseidon data base System On line PAL data: using the Poseidon data base system averaged every three hours Number of marine mammals Rainfall rate (mm/hr) Wind speed (m/s) Buoy sites Pylos Parameters

Analyzing acoustic data-Detecting marine mamals Whale call “Transient killer whale” Cape Flattery Echo-location click

Engine whine Killer Whale Call - Ugamak Bone crunching Pacific Right Whale “gunshot” Analyzing acoustic data-Detecting marine mamals

Conclusion & Future work Low duty cycle recorder can –Monitor the background sound budget –Measure background physical environment –Detect pods of killer whales –Identify specific pods from the sound bites –Provide evidence of the interaction of animals in the acoustic sounds cape

Acknowledgements NOAA NWFSC NOAA NMML ONR Ocean Acoustics NSF Physical Oceanography For the Poseidon/PAL integrated system: The people of the Aegean R/V, Mr. Dionysis Ballas and Mr. Paris Pagonis for the designing and deployment of PAL to the two Poseidon Buoys. More info: