CONTENTS 



INTRODUCTION . . . page 5 



SUMMARY OF LITERATURE ... 6 



SUMMARY OF PUBLISHED DATA ... 8 



Estimated Source Levels ... 8 



Offshore Drilling Activities in the Prudhoe Bay Area ... 8 



Tufts Point Dredging Site/Amak Artificial Island Construction Site ... 1 2 



Logistic Traffic Noise at the Tufts Point Site ... 1 2 



Semi-Submersible Platform in the North Atlantic ... 12 



UNDERWATER HEARING OF MARINE MAMMALS ... 14 

 Sound Production and Hearing of Large Whales ... 16 



DISCUSSION. . . 18 



RECOMMENDATIONS ... 20 



REFERENCES. . . 21 



ILLUSTRATIONS 



1 Average source level of noise generated from two drilling sites in Prudhoe Bay ... 9 



2 Average source level of noise generated from a construction site in the Beaufort Sea ... 9 



3 Average source level of noise generated from a construction site in the Beaufort Sea ... 1 



4 Maximum source levels of transient noise generated from a construction site in the 

 Beaufort Sea ... 1 



5 Maximum source levels of the noise generated by logistic support traffic measured in 

 the vicinity of a construction site in the Beaufort Sea ... 1 1 



6 Maximum source levels of the noise generated from a semi-submersible drilling 

 platform located in the Atlantic Ocean ... 1 1 



7 Behavioral underwater audiograms (smoothed curves) for the beluga whale and the 

 bottlenosed porpoise ... 15 



8 Behavioral underwater audiograms (smoothed curves) for the harbor porpoise and 

 the killer whale. 



9 Behavioral underwater audiograms (smoothed curves) for the California sea lion, 

 the harp seal, the ringed seal and the harbor seal ... 16 



10 Summary of possible effects of offshore drilling noise on marine mammal popula- 

 tion . . . 19 



TABLES 



1 Estimated distances from which noise from oil and gas drilling activities might be 

 detected by marine mammals ... 13 



2 Summary of source level data for cetaceans ... 1 7 



H-5 



