Blackburn, M. 1965. Oceanography and the ecology of 

 tunas. Oceanogr. Mar. Biol. Annu. Rev., H. 

 Barnes, Editor, 3:299-322. 



A review article on the effects of the envi- 

 ronment on the distribution and abundance of 

 tunas. The paper considered all commerical 

 species of tunas; and among oceanographic 

 factors listed are temperature, salinity, 

 oxygen, transperancy , nutrients, currents, 

 water masses, fronts, thermocline, topog- 

 raphy. 



KEY WORDS: tunas, yellowfin, bluefin, big- 

 eye, skipjack, distribution, geography, 

 abundance, depth, temperature, salinity, 

 oxygen, transparency, nutrients, currents, 

 fronts, upwelling, discontinuities (conver- 

 gence/divergence), thermocline, wind. 



Blackburn, M. 1969. Conditions related to upwelling 

 which determine distribution of tropical tunas off 

 western Baja California. U.S. Fish Wildl. Serv., 

 Fish. Bull. 61:147-176. 



Presented results from six oceanographic 

 cruises relating temperature, chlorophyl 1-a , 

 forage and tuna distributions. An hypothesis 

 was tested that tunas generally do not aggre- 

 gate in waters less than 20 C even when suit- 

 able food is abundant. 



KEY WORDS: tuna, yellowfin, skipjack, ocean- 

 ography, temperature, nutrients, food, color, 

 upwelling, bottom features. 



Blackburn, M., and R.M. Laurs. 1972. Distribution of 

 forage of skipjack tuna ( Euthynnus pelamis ) in the 

 eastern tropical Pacific. U.S. Dep. Commer., NOAA 

 Tech. Rep. NMFS SSRF 649, 16 p. 



The authors related skipjack forage distribu- 

 tion and oceanographic features to their 

 potential for indicating areas suited to 

 skipjack habitation and fishing. Made use of 

 EASTROPAC data for 1967-68. Areas with high 

 concentrations of forage could offer fishing 

 potential for skipjack. 



KEY WORDS: tuna, skipjack, feed, season, 

 distribution, upwelling, temperature. 



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