172 



Dr. Fox. No direct original information. 



Mr. Legoett. How did you gain your information with respect to 

 the current sizes of the stock? 



Dr. Fox. On the basis of aerial and ship surveys, primarily. 

 Mainly aerial survey to fret the density of the porpoises. 

 Mr.* Legoett. What did your survey consist of? 

 Dr. Fox. Flyinir a Grumman Goose approximately 11.000 track 

 miles out 500 or 000 miles from the southern tip of Raja, Calif., down 

 to the Central America bight. And there was information which 

 was utilized from tuna and research vessels which have plied 

 throughout this whole area. 



Mr. Legoett. That was on one flight? 



Dr. Fox. It was a series of flights' conducted in 1974. We currently 

 have a much more extensive aerial survey under way right now. 



Mr. Leggett. Is your current survey verifying the original sta- 

 tistics you collected? 



Dr. Fox. We are still collecting the data and have not had a chance 

 to analyze it. 



Mr. Legoett. You do not plug it in on daily basis? 

 Dr. Fox. No, we cannot do it. The current estimate of the eastern 

 spinner population is somewhere between 800,000 to 1.8 million. 

 That would be a 95-percent confidence interval. 

 Mr. Leggett. Also 125-percent error. 

 Dr. Fox. Top to bottom? 

 Mr. Leggett. Right. 



Dr. Fox. There is quite a bit of statistical imprecision in the 

 estimate, is that correct. 



Mr. Leggett. What is the error associated with this 125-percent 

 range that you have between the 800,000 and 1.8 million? 

 Dr. Fox. I do not believe I understand the question. 

 Mr. Leggett. You indicate there is somewhere between 800,000 and 

 1.8 million? 



Dr. Fox. That is correct. 



Mr. Leggett. To what extent can those figures be wrong? 

 Dr. Fox. Based upon the assumptions, assuming a normal distri- 

 bution, and assuming the variances on the whole set of assumptions, 

 there is a 5-percent chance that the population lies outside of those 

 bounds. 



Mr. Leggett. So based on this, then, is it not true, or is it true, 

 that the report did not make a finding that fishing in association with 

 any species or stock of porpoise associated with tuna should be 

 stopped ? 



I am referring to the workshop on stock assessments. 

 Dr. White. I do not recall that particular language. Does that 

 come directly from the report? 



Mr. Leggett. I guess the implication from the report is, that if 

 the report says that no stock was biologically depleted, then the im- 

 plication would be that no stock should not be incidentally taken. 

 Now what you state is that biological depletion is not the test? 

 Dr. White.* That is right. 



Mr. Leggett. Therefore, the workshop drew conclusions which 

 were either beside the point or on an erroneous premise? 



