52 



COMMERCIAL FISHERIES REVIEW 



Vol. 28, No. 7 



on into the Caribbean by the net flow. One 

 clockwise eddy, about 30 miles in diameter, 

 was nearly replaced by a counter-clockwise 

 eddy of about the same size in 3 days, indi- 

 cating that conditions in the area change rap- 

 idly. 



Potential forage organisms were collected 

 by neuston-net tows and night light. Oceano- 

 graphic measurements (temperature, salinity, 

 inorganic phosphate and oxygen) were made 

 to depths of 300 or 500 meters (984 to 1,640 

 feet) with a salinity -tennperature -depth probe 

 and with Niskin water samplers. Mechanical 

 and electronic failures of the salinity-temper- 

 ature-depth probe resulted in its use only 

 during portions of the cruise. Surface and 

 oblique 1 -meter (3.3 feet) net tows, primary 

 productivity measurements, and meteorologi- 

 cal observations also were taken. 



Aerial Fish Spotting: An airplane used 

 during the portion of the cruise from Puerto 

 Rico to Trinidad resulted in an increase in 

 the number of fish schools sighted. The plane, 

 which flew on a search pattern perpendicular 

 to that of the vessel's track, increased the 

 area of search and the efficiency of the en- 

 tire survey operation. In 6 days during which 

 the plane and vessel operated together in the 

 area from St. Vincent's Island south to Gre- 

 nada, 6 schools of tuna were sighted by the 

 vessel and 19 were sighted by the plane. In 

 several instances, the plane was able to di- 

 rect the vessel to a school which otherwise 

 would not have been sighted or sampled. 



MISSION 2: Investigation of the Biology 

 and Ecology of Bait Fishes: Bait fish were 

 observed in potentially useful quantities only 

 near the Gulf of Cariaco, Venezuela. Spanish 

 sardines ( Sardinella sp.) obtained from the 

 Gulf of Cariaco survived well in the bait tanks 

 and acted successfully to attract tuna to the 

 vessel. No bait fish in sufficient quantities 

 were observed in the Bahamas, the Lesser 

 Antilles, nor at Puerto Rico. 



The R/V Undaunted was scheduled to start 

 Cruise 5 on July 18, 1966. The area of oper- 

 ations for this cruise will be the northeast 

 and east coasts of South America between 

 Trinidad and Rio de Janeiro, and in the vi- 

 cinity of the islands of Ilha Trinidade and 

 Martin Vaz, Atol das Rochas, Fernando 

 Noronha, and Roche dos Sao Paulo. 



The cruise missions will be: (1) Investi- 

 gation of the biology and ecology of surface 



tuna and other pelagic predators, together with 

 measurements of the physical and biological 

 environment in the waters between Trinidad 

 and Rio de Janeiro; (2) Investigation of the lo- 

 cation and abundance of fish suitable as live 

 bait for tuna fishing; (3) Investigation of the 

 oceanographic features associated with di- 

 vergence of the South Equatorial Current off 

 the easternmost extension of Brazil; and (4) 

 Collection of ichthyological specimens from 

 previously under -sampled areas of significant 

 zoogeographic importance. 



Note: See Commercial Fisheries Review , April 1966 p. 38, 



Tuna 



1966 ALBACORE AND BLUEFIN TUNA 

 CATCH FORECAST FOR 



UNITED STATES PACIFIC COASTAL AREA: 

 This temperate tuna forecast for 1366 is 

 the sixth in a series of annual predictions for 

 the seasonal albacore and bluefin tuna fisher- 

 ies off the Pacific Coast prepared by the staff 

 of the Tuna Forecasting Program, U, S. De- 

 partment of the Interior, Bureau of Commer- 

 cial Fisheries Tuna Resources Laboratory, 

 La Jolla, Calif. 



Over the past six seasons, the Bureau's 

 Tuna Resources Laboratory has succeeded in 

 predicting the region where the July albacore 

 fishery occurs, largely because of a reason- 

 ably good "fix" on ocean environmental condi- 



Cross-hatched area delineates the area expected to produce about 

 two -thirds of the total July 1966 albacore tuna catch off south- 

 em California and Baja California (Mexico). 



