Posted on May 21, 2014
Sonobuoys are expendable underwater listening devices that the Navy typically employs for submarine detection, classification and location. Although models and capabilities vary, sonobuoys generally include a float (i.e., buoy), radio transmitter, battery and a hydrophone attached to a wire for detecting sound under water. Relatively inexpensive, simple and compact, sonobuoys are one of the most useful tools for monitoring underwater sound. They are well suited to marine mammal work—their frequency detection ranges encompass many whale sounds, and they can be deployed from both aircraft and ships.
Prior to 2009, some marine mammal researchers recognized the potential benefits of using the buoys as passive monitoring devices and often requested expired devices for their research. The success rate of expired devices, however, varied greatly from one batch to another, limiting their value relative to the effort of storing, transporting and deploying them.
In 2009, a convergence of need and opportunity helped to make unexpired sonobuoys from the Navy’s research inventory available for marine mammal research and environmental monitoring uses. There was growing recognition of the need to understand more about marine mammal presence in Naval training areas, and other marine areas, accompanied by increasing appreciation of the value of sonobuoys in meeting that need. Since the Naval Research Laboratory’s (NRL) needs for sonobuoys was on the decline, the Navy’s Non-Combat Expenditure Allocation (NCEA) of sonobuoys to the NRL included a quantity of unexpired sonobuoys that could be made available to researchers.
READ THE FULL ARTICLE