MARINE MAMMAL COMMISSION - Annual Report for 1998 



Preliminary results of the GulfCet Program were 

 reviewed at an information transfer meeting held by 

 the Minerals Management Service on 8-10 December 

 1998 in New Orleans. During the meeting, informa- 

 tion on the effects of seismic operations and drill rig 

 removal on marine mammals and sea turtles also was 

 reviewed. A representative of the Marine Mammal 

 Commission attended the meeting and participated on 

 a panel of agency and industry representatives that 

 was asked to comment on information provided. 



During the panel discussions, it was noted that the 

 GulfCet Program had documented both high species 

 diversity and high abundance of marine mammals in 

 the northern Gulf, particularly in offshore areas. It 

 also was noted that the distribution of most species, 

 including sperm whales, appears to be associated with 

 cold water rings that produce upwellings and have 

 high primary and secondary productivity. In this 

 regard, the GulfCet Program is one of the few marine 

 mammal programs that has attempted to identify the 

 distribution patterns and environmental factors affect- 

 ing marine mammal distribution and behavior, as well 

 as the composition and abundance of marine mammals 

 in an area of interest. 



Oil and gas exploration and development have been 

 ongoing in the northern Gulf of Mexico since the 

 early 1960s. Thus, there has been and continues to be 

 much seismic profiling and other development-related 

 activities that produce noise that may affect marine 

 mammals and other marine organisms. Currently, for 

 example, an average of three or four seismic surveys 

 are conducted in the northern Gulf every day, and 

 more than 100 exploration and development wells are 

 drilled every year. In addition, an average of more 

 than 1,000 boat trips and 2,000 helicopter trips are 

 made every day to transport personnel and equipment. 

 (See Chapter VII for additional information regarding 

 oil and gas exploration and development in the Gulf.) 



From experience in Alaska and California, there is 

 reason to believe that such noise can have at least 

 short-term effects on the distribution and behavior of 

 some marine mammals (for examples, see W. J. 

 Richardson, C. R. Greene, Jr., C. I. Malme, and D. 

 H. Thomson. 1995. Marine Mammals and Noise. 

 Academic Press. San Diego, California. 575 pp.). 

 However, nothing has been done since the Marine 



Mammal Protection Act was enacted in 1972 to (a) 

 identify, model, and verify the transmission character- 

 istics of the types of sound produced by seismic 

 profiling and other noise-generating activities in the 

 northern Gulf; (b) determine the likely species-specific 

 zones of influence of the various sources; (c) deter- 

 mine whether and how the distribution, abundance, or 

 productivity of any resident species or populations 

 may have been affected by the sound fields; or (d) 

 assure that any effects on survival or productivity of 

 marine mammals in the northern Gulf are negligible. 



Because exploration and development have been 

 ongoing in the northern Gulf for nearly 40 years, it is 

 possible that many or all of the potentially affected 

 marine mammal species have become accustomed to 

 the noise and no longer are affected by it. It also is 

 possible that some or all of the potentially affected 

 species have altered their habitat-use patterns to avoid 

 noisy areas. Such effects could be species-specific, 

 age-specific, or area-specific. The biological signifi- 

 cance of such effects likely would depend on factors 

 such as whether the habitats to which animals are 

 displaced are less productive or otherwise less suitable 

 than those previously occupied. 



The Minerals Management Service is planning to 

 hold a workshop in June 1999 to more clearly define 

 such uncertainties and determine what can be done to 

 resolve them. The Marine Mammal Commission, in 

 consultation with its Committee of Scientific Advisors, 

 will help in any way that it can to help structure the 

 workshop to ensure its success. 



Workshop on the Effects of Anthropogenic 

 Noise in the Marine Environment 



The Office of Naval Research held a workshop on 

 10-12 February 1998 to identify critical research 

 needs regarding the effects of anthropogenic noise on 

 marine mammals and other marine organisms, includ- 

 ing fish and sea turtles. Participants, including 

 representatives of the Marine Mammal Commission, 

 had expertise in the fields of ocean acoustics; the 

 effects of sound on the physiology and hearing of 

 marine mammals, fish, terrestrial vertebrates, and 

 humans; and mitigating noise effects on marine 

 mammals. The workshop report, expected to be 



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