The prediction for the 1968 season, issued in mid- 

 June, coincided with the detection of early arriving alba- 

 core tuna by David Stan Jordan outside the California 

 offshore islands during an anchovy-sardine survey. 



This year (1968) the open ocean on the migratory 

 route of albacorc tuna towards the Pacific Coast has 

 shown strong warming trends in late May and early June. 

 If this warming continues, we can expect to see an appre- 

 ciable portion of the incoming migrants diverted into 

 northern California waters instead of towards Baja Cali- 

 fornia. Thus, the area near Guadalupe Island may pro- 

 duce few early-season catches, and we e.xpect the fishery 

 to advance relatively rapidly toward central California, 

 from San Juan to Davidson Seamounts. 



Total California landings for the season cannotyet 

 be estimated, but we expect they may fall near the long- 

 term average of about 15,000 tons. The Oregon- 

 Washington region is expected to receive a significant 

 portion of the total U.S. West Coast catch of albacore 

 tuna this year. 



In 1968, the blucfin tuna fishery is expected to de- 

 velop later than usual because southern Baja California 

 has had a period of strong northerly winds; heavy weather 

 created by these winds has severely hmited fishing and 

 has caused intense upwelling with a near-shore band of 

 green waters and sea temperatures considerably lower 

 than normal. 



These events have combined to delay the onset of 

 the fishery well into the month of June and may cause 

 the bluefin tuna to remain farther offshore than usual. 

 One consequence of the delay in the start of the bluefin 

 tuna season will be a northward shift in the center of 

 production and a delay in the period of maxmium catch. 

 Rapid warming in the region north and east of Guadalupe 

 Island may cause bluefin tuna to appear earlier than last 

 year in southern California waters. 



G.A. Flittner and his colleagues also continue basic 

 environmental research and investigate the methods of 

 predictive analysis. R.J. Lynn has completed his rework- 

 ing of the data base from the CalCOFI oceanographic 

 studies in the California Current and has reanalyzed the 

 seasonal variation of temperature and salinity at 10 m. in 

 the California Current; these studies permit much more 

 precise definition of seasonal anomalies to be made and 

 are of direct application in the predictive process. 



N.E. Clark has started work on the heal tlux at the 

 sea surface in the northeastern Pacific Ocean and has 

 accumulated oceanographic and nieteorological data for 

 a long period of years. He is using these data to write 

 and test computer programs for prognostic charts of sea 

 surface temperature, from historical data and his heat 

 flux computations. He has also been studying, from his- 

 torical data, the winds and sea surface temperatures off 

 California, to describe the mechanisms involved, and to 



predict coastal upwelling. 



R.J. Lynn has been continuing his collaboration 

 with J.E. Reid of SIO on the characteristics and circula- 

 tion of deep and abyssal waters. Potential temperature 

 and salinity of these waters in the major areas of the 

 world ocean have been reexamined in the hope that re- 

 cent data may extend the conventional concept of the 

 formation and circulation of the deeper waters. 



The results were consistent with the conventional 

 notions of deep flow except for potential density, which 

 appears not to fit in the Atlantic. Further examination 

 has revealed that above the bottom in the western Atlan- 

 tic is a potential density maximum which represents fairly 

 well the lower north Atlantic deep water. Introduction 

 of a new density increase explains the peculiarities of the 

 distribution of potential density. 



A second study concerns also the abyssal waters of 

 the world's ocean and presents new techniques in the 

 analysis of deep water along density surfaces. This pro- 

 ject uses these techniques to develop a model that de- 

 scribes the sources and paths of waters which mix and 

 ultimately fill the depths of the Pacific Ocean. This deep 

 Pacific water is relatively homogenous in its characteris- 

 tics; as defined within a narrow range of temperature 

 and salinity it has been termed "common water"" and 

 constitutes 44 percent by volume of the Pacific Ocean. 

 It is thus very important in determining the major char- 

 acters of this ocean basin. 



EASTROPAC 



EASTROPAC is a multiagency. international series 

 of expeditions designed to investigate the seasonal 

 changes over a rather large part of the eastern tropical 

 Pacific Ocean, extendnig from the west coast of Mexico 

 to the northern coast of Peru, and to 122 W., far to the 

 west of the Galapagos Islands. The field surveys began 

 in early 1967 and continued througli April 1968. 



BCF, througli the Fishery -Oceanography Center, 

 was the lead agency. W.S. Wooster of SIO was initially 

 Coordinator of the expeditions and was responsible for 

 early planning and organization. Subsequently, A.R. 

 Longhurst, of the Fishery-Oceanography Center, became 

 Coordinator. 



Six vessels from the United States worked the 

 main observational lines in the offshore survey area; these 

 cruises ranged from one-ship to four-ship surveys and 

 comprised one summer and two winter surveys, linked 

 by four single-ship monitoring cruises in the interim peri- 

 ods. Five vessels from Mexico, Peru, Ecuador, and Chile 

 participated in the expeditions and timed their cruises 

 \o coincide with the major offshore surveys. In addi- 

 tion, five U.S. vessels which passed through the EAS- 

 TROPAC sui^vey area were considered to be ships of op- 

 portunity and worked oceanographic transects which 



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