On Saturday, July 19th, we conducted a Controlled Exposure Trial with the USS Donald Cook, a Navy guided missile destroyer based in Mayport, Florida. The trial involved playing Continuous Active Sonar (CAS) signals from the destroyer to a constellation of eight satellite-tagged beaked whales off Cape Hatteras. We used real-time acoustic propagation modeling to ensure that received levels for the whales were within our target range. We will be analyzing the behavioral response of the tagged whales over the coming months and comparing these observations with past experimental exposures to Pulsed Active Sonar (PAS) signals.
The R/V Shearwater was on the water to monitor the response of the focal whale, ZcTag156, and several other whales, in real time. We are continuing to receive data uploads from all the tagged whales via satellite. The example below from ZcTag157, shows the data stream of diving behavior overlaid with the CAS exposure (in pink).
Field experiments like this are extremely challenging and require the hard work of a large number of people and institutions. Many thanks to Rob Kalin at FACSFAC JAX, who coordinated the CEE with the Donald Cook, Ron Filipowicz from USFFC for project co-ordination, and Joel Bell from NAVFAC, who was aboard the Shearwater for the trial. Thanks to everyone on the tagging and tracking teams for conducting this challenging work. And a very special thanks from all of us in the science party to the officers and crew of the USS Donald Cook, for making this experimental trial happen.
