types and possible effects of oil spills and activities expected 

 as a result of the proposed and alternative actions. The 

 Commission also noted that some of the conclusions concerning 

 possible adverse effects on marine mammals appear to be specu- 

 lative and based on unstated assumptions. 



With respect to potential impacts on both endangered and 

 non-endangered marine mammals, the Commission recommended that 

 the Draft Statement be modified to: (a) emphasize the impor- 

 tance of post-sale monitoring efforts; (b) consider that, as 

 a result of the proposed action, animals may move into adjacent 

 and already occupied areas, thereby increasing animal densities 

 in those areas to levels which could damage or deplete food sup- 

 plies; (c) consider the cumulative impacts of oil spills and 

 disturbances on affected animals throughout their ranges rather 

 than just within and near the proposed sale area; and (d) con- 

 sider the possible cumulative effects of subsistence harvesting 

 and other activities, as well as oil and gas activities, on both 

 endangered and non-endangered marine mammals. 



In its letter, the Commission further noted that the 

 Statement identified a number of potential mitigating measures 

 that could help reduce potential impacts on marine mammals and 

 other marine species. It recommended that these measures be 

 included as part of the proposed action. 



Potential PCS Lease Sale #95 

 Offshore Southern California 



During 1987, the Minerals Management Service began the 

 planning process for proposed Lease Sale #95 in the Southern 

 California OCS Planning Area. The Sale is tentatively scheduled 

 for September 1989. The area under consideration involves 

 approximately 1,373 whole or partial blocks covering some seven 

 million acres, located from 3 to approximately 130 miles from 

 shore. In its 9 July 1987 Call for Information and Nomina- 

 tions, the Service asked the Commission and others to identify 

 any issues and areas of concern related to offshore oil and 

 gas exploration and development in the proposed sale area. 



By letter of 24 August 1987, the Commission, in consul- 

 tation with its Committee of Scientific Advisors, provided 

 the Service its comments and an outline indicating how offshore 

 oil and gas development could affect marine mammals. It its 

 letter, the Commission noted that noise and other disturbance 

 from seismic exploration, platform construction and drilling, 

 and routine operations may cause some species of marine mammals 

 to abandon or avoid important breeding, feeding, and haul-out 

 areas and migration routes. The potential effects of such 

 disturbances could equal or exceed those that might result 

 from catastrophic oil spills. Thus, the Commission stressed 



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