Acoustic Recording Package deployment
An Acoustic Recording Package (ARP), designed by Dr. John Hildebrand's lab at Scripps Institute of Oceanography, La Jolla, California, was deployed at 66º 44.24′S, 69º 48.72′E on 8 February 2003. The instrument is designed to sit on the sea floor and passively record acoustic signals for a period of about one year. The instrument samples at 500 Hz, giving an effective bandwidth of 0.1-250 Hz. This frequency range is sufficient to record the low frequency sounds of blue and fin whales, potentially some sounds from humpback and minke whales, plus some of the lower frequencies of Antarctic seal calls. Additionally, ice noise and geophysical signals, such as earthquakes, may be recorded. The sample rate is not sufficient to record sounds from most toothed whales, such as sperm or killer whales. Data are sampled continuously for the duration of the deployment. The instrument needs to be recovered in order to retrieve the data. These data will be the first long-term recording of underwater acoustic signals in the Australian Antarctic and should provide valuable information as to the seasonal presence/absence of calling whales and information on the characteristics of their calls. Information from similar instruments placed off the Antarctic peninsula have already provided very novel and interesting information on the occurrence of blue and fin whales in that region. Those data will be compared to the data from the Mawson instrument and an instrument being deployed off the British Antarctic Survey ship to examine geographic differences in large whale occurrence in the Antarctic.
Deploying the ARP
Kate and Julie monitoring pilot whale acoustics