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Dr. White. We do not believe it would be practical to avoid the 

 set, and if the tiling was done with every pood intention we would 

 consider it an accidental thing, unless half of the porpoises in there 

 turn out to be spinners, in which case, there would be some reason 

 to believe that it. was not accidental. 



Mr. Leggett. Is it your general impression that if you have got 

 a reasonable, significant mix of spinners in a set that normally you 

 would be able to determine that prior to the encirclement, Dr. 

 White? 



Dr. White. We are hoping in most cases that they will be able to 

 do so. 



You have people here, captains and people from the industry, who 

 will be able to do that. 



Mr. Leggett. Do your regulations address themselves to that ? 



Dr. White. If a captain was able to determine that there were 

 spinners in a porpoise school, he would not be allowed to set on it. 

 We have to count on the good faith of our tuna skippers. 



Mr. Anderson. Could I interject one question? 



Mr. Leggett. Mr. Anderson. 



Mr. Anderson. How do you distinguish between the white belly 

 pirhouette and the eastern spinner? 



Dr. White. I believe they are distinguishable. 



Dr. Fox. We are talking about spinners, which is one species. We 

 are talking about eastern spinners and white belly. There are racial 

 and slight morphological differences which constitute a stock, but not 

 a separate species. There are certain things which are very distin- 

 guishable between the large adults, particularly the males. The large 

 male eastern spinners have a forward facing dorsal fin. There is diffi- 

 culty in identification when looking at small females or juveniles and 

 young adults to tell the eastern spinners from the white bellies. 



Mr. Anderson. Do they pirhouette differently? 



Dr. White. They only pirhouette when they are free ranging. I 

 do not believe that they pirhouette when they are in the net. 



Mr. Anderson. So you do not really see them? 



Mr. Leggett. As they are ranging, so as you approach the encircle- 

 ment, would you find them doing their peculiar activity? 



Dr. Fox. They only pirhouette if they are free-ranging. If the 

 school has been stopped by the action of the net to encircle it, I do 

 not believe that vou would see them pihouetting at that time. 



Mr. Leggett. From your knowledge and experience in the indus- 

 try, and I expect you are the most knowledgeable person in XOAA. 

 with the exception of perhaps some observers, that you supervise, is 

 it your opinion that a captain can discriminate between a mixed 

 school of eastern spinners and other kinds of porpoise at any time 

 prior to the time that the set is complete? 



Dr. White. Well, there are certainly other people in the program 

 who have extensive field experience and that could answer the ques- 

 tion better than I. It is my understanding from those people that 

 there is a likelihood of identifying the difference between eastern and 

 white bellied spinners, particularly if vou are in two relatively dis- 

 tinct ireographical areas. In an area between these two centers of 

 distribution you are likely to find animals that look like one or the 

 other because it is all one species. These are stock differences. 



