What is a geophysical/seismic survey?
A. Geophysical/seismic surveying is a method of mapping below the sea floor using sound waves. The sound waves, typically made with bursts of air or combustion similar to a car’s piston, are reflected back from rock layers below the sea floor and are recorded. Geophysicists use these data to look for potential oil and gas resources. One of the concerns expressed in the past when seismic surveys are proposed are effects on marine mammals. At this time, information on the effects of noise on marine mammals is limited and is not conclusive one way or the other about significant effects on marine mammals. While there are only limited data available to evaluate the effects from this noise on marine mammals, seismic surveys cover thousands of survey miles yearly throughout the world oceans, with no reported effects on marine mammal numbers or distribution in the surveyed areas. The National Marine Fisheries and other marine mammal researchers continue to study this issue. In the interim, to
