As noted in the previous Annual Report, the ship surveys 

 were only part of the monitoring program under development by 

 the Service. The other two aspects consisted of (1) analyses 

 of data collected by observers aboard tuna purse seiners, and 

 (2) analyses of biological and behavioral data collected from 

 both research and fishing vessels. 



On 13 November 1985, a meeting was held to address the 

 use of tuna vessel observer data to index trends of abundance 

 of eastern tropical Pacific porpoise, and the final report of 

 that meeting was received by the Commission early in 1986. 

 The meeting participants, including representatives of the 

 Commission, set priorities for research topics to be under- 

 taken, and identified the five most important research needs: 

 (1) apply appropriate line transect methodology to all avail- 

 able data; (2) study and apply data-dependent stratification 

 procedures; (3) compare tuna vessel observer data and 

 research vessel data for areas where both were collected 

 simultaneously; (4) explore sampling properties of existing 

 observer data by sub-sampling; and (5) examine environmental 

 effects on abundance estimates. 



The meeting emphasized the importance of cooperating 

 with the Inter-American Tropical Tuna Commission and the 

 industry in carrying out this phase of the monitoring 

 program. Unfortunately, the Service did not designate a 

 leader for this program for several months following the 



13 November 1985 meeting. To date, there have been no 

 reports on any of these recommended studies. 



As noted above, in October 1986, the U.S. tuna fleet was 

 required to stop fishing on porpoise schools because it had 

 already taken the maximum number of porpoise allowed under 

 the existing quota. This raised issues with respect to the 

 methodology for calculating the in-season estimates of the 

 porpoise kill and for extrapolating from these to project the 

 date on which the quota would be reached. To this end. 

 Commission representatives met with Service personnel on 



14 July and 6 December 198 6, as reported above, to provide 

 advice on the methodology and to recommend research to evalu- 

 ate possible alternative procedures. Some simulation studies 

 were carried out in 1986 and further studies ere planned for 

 1987. In addition, as recommended in the Commission's letter 

 of 23 December 1986, additional research will be conducted to 

 determine whether and how to refine the mortality estimation 

 methodology. The Commission will participate in this and 

 other research activities during 1987. 



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