FISHERY BULLETIN. VOL. 86, NO. 2 



a 2° stratification would be necessary to avoid 

 biases in these areas. 



ACKNOWLEDGMENTS 



I wish to thank Peter Frank and Tim Smith for 

 their generous support and useful comments dur- 

 ing the research presented here. This paper would 

 not exist without the data collected by the Na- 

 tional Marine Fisheries Service observers. I wish 

 to acknowledge these observers and the staff of 

 the Southwest Fisheries Center of the National 

 Marine Fisheries Service for collecting, editing, 

 and initially preparing these data. A number of 

 the staff of the Southwest Fisheries Center pro- 

 vided support and technical assistance at various 

 stages in this research. The number of people in- 

 volved is too large to acknowledge all of them 

 individually. Special thanks go to Phil Tarentino, 

 Michael Lichter, and Susan Boyer. 



The art department of the Southwest Fisheries 

 Center were responsible for the final preparation 

 of some of the figures. Veronica van Kouwen 

 helped with the preparation of the final 

 manuscript. 



The manuscript is a portion of a Ph.D. Thesis 

 submitted to the University of Oregon, Eugene, 

 OR. 



LITERATURE CITED 



Allen, R., and R. Punsley. 



1984. Catch rates as indices of abundance of yellowfin 

 tuna, Thunnus albacares , in the eastern Pacific Ocean. 

 Inter-Am. Trop. Tuna Comm. 18:303-379. 

 Blackburn, M., and F. Williams. 



1975. Distribution and ecology of skipjack tuna, Katsu- 

 wonus pelamis , in an offshore area of the eastern tropical 

 Pacific. Fish. Bull., U.S. 73:382-411. 

 Calkins, T. P. 



1963. An examination of fluctuations in the "concen- 

 tration index" of purse seiners and bait boats in the fish- 

 ery for tropical tuna in the eastern Pacific. Inter-Am. 

 Trop. Tuna Comm. Bull. 8:255-316. 

 Calkins. T. P., and B M Chadwin. 



1967. Geographical distribution of yellowfin tuna and 

 skipjack catches in the eastern Pacific Ocean, by quarters 

 of the year 1963-1966. Inter-Am. Trop. Tuna Comm. 

 Bull. 12:435-508. 



1971. Geographical catch of yellowfin and skipjack tuna 

 in the eastern tropical Pacific Ocean, 1967-1970, and 

 fleet and total catch statistics. Inter-Am. Trop. Tuna 

 Comm. Bull. 15:285-377. 



Clark. C. W., and M. Mangel. 



1983. Search theory in ecology and resouce manage- 

 ment. In M. Freedman (editor). Proceedings of the In- 

 ternational Conference on Population Biology, p. 380- 

 388. Springer Lecture Notes in Biomathematics, Vol. 

 52. Springer Verlag, N.Y. 



Cooper. E 



1979. Home range criteria based on temporal stability of 

 areal occupation. J. Theor. Biol. 73:687-695. 



GULLAND, J. A 



1955. Estimation of growth and mortality in commerical 

 fish fxipulations. Fish. Invest. Minist. Agric. Fish. Food 

 (G.B.), Series 2. 18:1-46. 

 Helland Hansen, B 



1909. Statistical research into the biology of the haddock 

 and cod in the North Sea. Rapp. P-v R6un 10:1-62. 

 Koopman, B O 



1980. Search and screening. Pargamon Press, N.Y., 

 509 p. 



Orbach, M K 



1975. The cultural system of the tuna seinermen of San 

 Diego, California. Ph.D Thesis, Univ. California, San 

 Diego, CA, 411 p. 



Pazynich, G I 



1966. Primery primeneniya teorii statisticheskiskh resh- 

 enii k zadacham taktiki promysla (Examples of the appli- 

 cation of statistical-solution theory to problems in the 

 fishing tactics). Noe Khoz. 6:80-81. (Translation 

 available in the library of National Marine Fisheries 

 Service Northeast Fishery Laboratory, Woods Hole, MA.) 



Perrin, W. F. 



1968. The porpoise and the tuna. Sea Frontiers 14:166- 

 174. 



1969. Using porpoise to catch tuna. World Fishing 

 18:42-45. 



POLACHECK, T 



1983. The relative abundance of dolphins in the eastern 

 tropical Pacific based on encounter rates with tuna purse 

 seiners. Ph.D Thesis, Univ. Oregon, Eugene, OR, 444 p. 



Sall\, S. B., AND J M. Flowers. 



1979. Elementary applications of search theory to fishing 

 tactics as related to some aspects of fish behavior. 

 F.A.O. Conference on Fish Behavior in Relation to Fish- 

 ing Techniques and Tactics, p. 343-355. 



Sanderson, G. 



1966. The study of mammal movements - a review. J. 

 Wildl. Manage. 30:215-235. 



SCHOENER, T W 



1981. An empirically based estimate of home range. 

 Theor. Popul. Biol. 20:281-325. 



Snedecor, G W , AND W C. Cochran 



1967. Statistical methods. 6th ed. Iowa State Univ. 

 Press, Ames, 593 p. 



Suzuki, Z , P K. Tomlinson, and M Honma. 



1978. Population structure of Pacific yellowfin tuna. 

 Inter-Am. Trop. Tuna Comm. Bull. 17:277-411. 

 SwiHART, R. K . and N. a. Slade. 



1985. Influence of sampling interval on estimates of home 

 range size. J. Wildl. Manage. 49:1019-1025. 



366 



