Schaefers, 1952 and 1953; Powell, 1957). The 

 Fish Commission of Oregon made independent 

 exploratory fishing and tagging cruises in 

 1959, 1960, and 1961.^ 



Albacore trolling has been conducted on 

 several oceanographic surveys off the 

 Washington-Oregon coast. In 1955 and 1956 

 oceanographic and biological data were 

 collected from the British Columbia, Washing- 

 ton, Oregon, and northern California coastline 

 out to about longitude 145° W. (Holmberg*; 

 Love, 1957). In the fall of 1956, vessels of the 

 Bureau of Commercial Fisheries Pacific 

 Oceanic Fishery Investigations collected data 

 from longitude ISO^W, to the American Pacific 

 coast between latitudes 31° N. and 460N. 

 (Callaway, 1957). The Northeastern Pacific 

 Albacore Survey (NEPAS) operated in 1957 be- 

 tween latitudes 35° N. and 47°N. (Callaway and 

 McGary, 1959; Graham, 1959). In 1958 the 

 area off Washington and Oregon was surveyed 

 as part of the International Geophysical Year 

 (Fleming and staff, 1959). 



On Exploratory Cruise 51 the M/VJohn N. Cobb 

 departed Seattle on July 10, 1961, and pro- 

 ceeded to the cruise track (fig. 1). The first 

 hydrographic station was occupied on July 1 1 

 and the last on July 26, 1961. During the 

 cruise, the Cobb drifted at night. The vessel 

 docked in Astoria, Oreg., on July 27. 



OBSERVATIONS AND FIELD PROCEDURES 



Physical and Chemical Methods 



Hydrographic stations usually were occu- 

 pied at noon and shortly after dark at inter- 

 vals of about 48 nautical miles (fig. 1, table 1). 

 Casts of 18 Nansen bottles each were made at 

 23 stations to depths of about 600 meters, and 

 casts of 9 bottles each were made at 2 stations 

 to about 120 meters depth. Results of physical 

 and chemical measurements are presented in 

 figures 2-10 and in tables 2-4. 



Nansen bottle spacings were determined by 

 characteristics of bathythermograph (BT) 



* Robert J. Ayers. 1959, 1960, 1961. Unpublished re- 

 ports of the Fish Commission of Oregon. 



'Edwin K. Holmberg. 1956. Unpublished report of the 

 Fish Commission of Oregon. 



traces obtained at each station and by antici- 

 pated wire angles. Because the hydrographic 

 wire was of small diameter (1/8 inch), two 

 casts were made at each station: a shallow 

 cast to sample from to 125 meters and a 

 deep cast to sample from 125 to 600 meters. 

 Paired protected reversing thermometers were 

 attached to each bottle, and most bottles 

 sampling below 100 meters were equipped with 

 unprotected reversing thermometers. Samples 

 were drawn for salinity and oxygen analysis. 

 Oxygen determinations were made aboard the 

 Co66,and salinity determinations were made at 

 the Department of Oceanography, University of 

 Washington. 



Bathythermograph casts to 900 feet were 

 made at each hydrographic station and at points 

 about halfway between stations (fig. 1, table 3). 

 The vessel was stopped for all BT casts. 

 Observations were made in accordance with 

 U.S. Navy Hydrographic Office Publication No. 

 606-c (1956). 



Drift bottles were released at 19 stations 

 (tables 1 and 2). These were provided by 

 Hans T. Klein, Data Collection and Processing 

 Group, Scripps Institution of Oceanography. 

 No recoveries had been received as of March 

 1962. 



Continuous recording of incident solar radia- 

 tion was made throughout the cruise. The 

 sensor used was a gimbal-mounted pyrano- 

 meter using Parsons' Black as the "black 

 body." A strip-chart recorder provided the 

 trace (table 4). 



Biological Methods 



Surface measurements of primary produc- 

 tion using the C^^ method were made at 21 

 stations. These were often coincident with 

 hydrographic station locations but are labelled 

 independently of hydrographic stations due to 

 occasional differences in time and location 

 (fig. 11, tables 1 and 5). The method employed 

 is a modification of those described by Stee- 

 mann Nielsen (1952), Strickland (1960), and 

 Strickland and Parsons (1960). Water samples 

 were obtained with a plastic bucket from the 



