Chapter III — Marine Mammal/Fisheries Interactions 



at a small population size, and a recovery factor of 

 between 0.1 and 1.0. Strategic stocks are those that 

 (a) have a level of direct human-caused mortality 

 exceeding the calculated potential biological removal 

 level, (b) are designated as depleted under the Marine 

 Mammal Protection Act, (c) are listed as endangered 

 or threatened under the Endangered Species Act, or 

 (d) are likely to be listed as endangered or threatened 

 in the foreseeable future. 



National Marine Fisheries Service — As dis- 

 cussed in previous annual reports, the National 

 Marine Fisheries Service published a Federal Register 

 notice in August 1995 announcing the availability of 

 its original stock assessments. The Service also pub- 

 lished a separate report describing the guidelines used 

 to identify stocks, determine minimum population 

 sizes, estimate maximum net productivity rates, and 

 select appropriate recovery factors. Of 145 stocks for 

 which the Service originally prepared assessments, 47 

 were determined to be strategic stocks. The Service 

 also designated as strategic 33 localized stocks of the 

 bottlenose dolphin that inhabit bays, sounds, and 

 estuaries in the Gulf of Mexico after concluding that 

 the minimum abundance estimates were so low that 

 the take of a single animal from most of these stocks 

 would exceed the calculated potential biological 

 removal level. 



Assessments for strategic stocks are to be reviewed 

 at least annually. For other stocks, assessments must 

 be reviewed at least once every three years. The 

 National Marine Fisheries Service began the process 

 of revising its stock assessments in 1996. Final 

 versions of these revised stock assessment reports 

 were published by the Service at the end of 1997. 

 The revised reports noted a changed status for seven 

 marine mammal stocks. The stocks of Baird's beaked 

 whales, Cuvier's beaked whales, and pygmy sperm 

 whales that occur in waters off California, Oregon, 

 and Washington, identified as strategic in the original 

 stock assessments, were found to be non-strategic. 

 The stock of minke whales inhabiting waters off 

 California, Oregon, and Washington was reclassified 

 as strategic as a result of a single observed fishery- 

 related mortality. Three stocks of cetaceans that 

 occur off the east coast of the United States, the 

 western North Atlantic stock of white-sided dolphins, 

 the western North Atlantic stock of bottlenose dol- 



phins, and the western North Atlantic stock of long- 

 finned pilot whales, were reclassified from strategic to 

 non-strategic in the revised assessments. 



The National Marine Fisheries Service published a 

 Federal Register notice on 24 July 1998 announcing 

 the availability of draft stock assessment reports for 

 1998. For stocks that occur in Alaska, the Service 

 proposed revisions to 15 of 33 assessment reports, 

 including all 10 strategic stocks. Although the revised 

 reports included new information on marine mammal 

 abundance and estimated mortality, no changes in the 

 status of these stocks were proposed. 



Two status changes were proposed for the 50 

 stocks that occur along the coasts of California, 

 Oregon, Washington, and Hawaii. In light of revised 

 abundance estimates resulting from a 1996 ship-based 

 survey, the Service believed that the California- 

 Oregon-Washington stocks of minke whales and 

 mesoplodont beaked whales {Mesoplodon spp.) should 

 be classified as non-strategic. Draft assessments for 

 two stocks of harbor seals, two stocks of harbor 

 porpoises, and the San Miguel stock of fur seals were 

 also revised to reflect new information. None of the 

 proposed changes, however, would change the status 

 of these stocks from non-strategic. 



Of the 57 stock assessments that had been prepared 

 for marine mammals occurring in the Atlantic Ocean 

 and Gulf of Mexico, the Service proposed revisions to 

 26. Based on new estimates of fishery-related inci- 

 dental mortality, the Service proposed changing the 

 status of the western North Atlantic stock of white- 

 sided dolphins from non-strategic to strategic. The 

 draft revised stock assessment for the western North 

 Atlantic stock of pygmy sperm whales indicated that 

 this stock should be reclassified as non-strategic 

 because no fishery-related mortalities or serious 

 injuries had been observed between 1992 and 1996. 



The Marine Mammal Commission provided 

 comments on the draft 1998 stock assessment reports 

 by letter of 21 October 1998. In general, the Com- 

 mission believed that the draft reports provided 

 thorough descriptions and assessments of marine 

 mammals stocks occurring in U.S. waters and infor- 

 mation on the levels of human-caused mortality and 

 serious injury affecting the stocks. The Commission 



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