MARINE MAMMAL COMMISSION — Annual Report for 1998 



necropsy samples before making the final determina- 

 tion, as required by the 1997 amendments. 



One study of particular interest to the Commission 

 was the capture rate estimation study proposed by the 

 Service in its draft research plan. The Commission 

 requested additional information on this study, noting 

 that it may be possible to design a study that would 

 enable the Service to correlate the frequency of 

 encirclement with unobserved dolphin mortality rates. 

 If this could be done, it would provide an important 

 means for supplementing the abundance surveys as a 

 way of detecting possible population level effects of 

 chase and encirclement. 



The Commission also noted that the results of the 

 required research are likely to be controversial and 

 advised the Service that it would be useful at the 

 outset to describe (1) what would be considered to be 

 evidence of stress-related effects on the recovery of 

 depleted dolphin stocks and/or (2) what steps, if any, 

 need to be taken to establish generally agreed upon 

 criteria that will be used to decide what would consti- 

 tute evidence that chase and encirclement of dolphins 

 is or is not impeding recovery of depleted stocks. 

 The Commission also believed that, if the Service 

 were to establish decision-making criteria at the 

 outset, the Commission and other reviewers would be 

 better able to comment on whether the proposed 

 studies were likely to provide adequate information. 



The Commission also inquired as to which dolphin 

 stocks would be factored into the Service's findings on 

 the effects of chase and encirclement on depleted 

 stocks. Although the Commission agreed that the 

 Service needed to look at the effects on northeastern 

 offshore spotted dolphins and eastern spinner dol- 

 phins, the two stocks designated as depleted under 

 section 115 of the Marine Mammal Protection Act, 

 the Commission questioned whether the effects on 

 coastal spotted dolphins also needed to be considered. 

 This stock, although not formally designated as 

 depleted under section 1 15 of the Act, was determined 

 to be below its optimum sustainable population level 

 in the last tuna-dolphin permit proceeding, held in 

 1980. Along with the eastern spinner dolphin, it has 

 been treated in subsequent legislation as though it 

 were depleted. 



Other points raised by the Commission included 

 the need for the Service to (1) estimate the magnitude 

 of the changes in dolphin populations that would have 

 had to occur in order to be detected within acceptable 

 levels of statistical confidence by the planned surveys, 

 (2) explain more clearly how planned ecological 

 studies would be factored into determining whether 

 the recovery of depleted dolphin stocks is being 

 impaired by chase and encirclement, and (3) include 

 studies on stress in humans as part of the review of 

 stress-related literature. 



The National Marine Fisheries Service responded 

 by letter of 5 August 1998. The Service indicated 

 that plaiming and implementing the various research 

 projects was an ongoing effort and pledged to keep 

 the Commission apprised of and involved in the 

 process. The Service agreed that developing decis- 

 ion-making criteria for the March 1999 finding was 

 desirable and noted that, because the initial determina- 

 tion would depend primarily on the results of the 1998 

 abundance survey, it was focusing on developing 

 criteria related to these data. The Service recognized 

 that the criteria would necessarily be based both on 

 science and on policy. As a first step, the survey data 

 would be compared statistically with expected results 

 to identify any difference that may be attributable to 

 chase and encirclement. The second step would be to 

 determine whether any such difference is significant. 



The Service characterized the necropsy sampling 

 program as "a complicated endeavor" requiring exten- 

 sive cooperation with other governments and with 

 non-U. S. fishing vessels. Despite efforts to arrange 

 for the placement of technicians on those vessels to 

 collect materials, the Service did not believe that 

 sampling would begin during fiscal year 1998. This 

 being the case, the Service indicated its intent to 

 increase sampling effort during subsequent years and 

 to extend the program beyond fiscal year 2000. The 

 Service also indicated that it was developing a com- 

 prehensive research plan for the necropsy study that 

 would describe the research objectives, necropsy 

 procedures, sampling and analytical design, and 

 processing protocols. 



With respect to the literature review, the Service 

 stated that its primary utility would be to provide a 

 context for the findings of other research projects by 



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