station 50 in February and April. Coverage extended seaward to 

 station 200 (approximately 600-700 miles offshore) on lines 60-90 

 (Cruises 6301 and 6304) but typically did not extend beyond 

 station 90 (approximately 160-260 miles offshore) 1 . Several 

 inshore stations were occupied during Cruises 6304, 6307 and 6310 

 which were not covered on early CalCOFI surveys. These stations 

 were included in the data base (Table 1) , but omitted from the 

 station plots (Figures 3, 4, and 5). 



Two vessels were employed on these cruises: the Alexander 

 Agassi z of SIO and the Black Douglas of NMFS . The Black Douglas 

 was used on all cruises and the Alexander Agassi z participated in 

 the first two (Univ. of Calif., SIO, 1963, 1964). 



SAMPLING GEAR AND METHODS 



The standard CalCOFI net used from 1949 to 1969 had a 1-m 

 diameter mouth opening (0.785 m area) and an overall length of 

 about 5 m. The net was constructed of 3 0xxx gauze, a heavy duty 

 grade of silk bolting cloth, with a mesh size of 0.55 mm after 

 shrinkage. The last 4 cm of the cone and the cod end were 

 constructed of 56xxx grit gauze which had a mesh size of 0.25 mm 

 after shrinkage. The net ring was fastened to a short 3-lead 

 bridle connected to several meters of line which attached to the 

 towing cable by a clamp. A current meter was suspended in the 

 center of the net mouth to measure volume of water filtered (see 

 Kramer et al . , 1972, for further details). 



The standard tow from 1951 through 1968 was an oblique haul 

 to 140 m depth (to 15 m of the bottom in shallow areas) designed 

 to filter a constant amount of water per depth interval (ca. 

 3m 3 /m of depth) over the vertical range of most ichthyoplankters. 

 Hauls were made at a ship speed of 1.5-2.0 knots and initiated by 

 clamping tne net line to the towing cable with the 4 5 kg terminal 

 weight about 10-15 m below the surface. The net was lowered to 

 140 m depth by paying out 200 m of wire over a 4 minute period 



■^CalCOFI lines (Figure 6) are arranged perpendicular to the 

 coastline and extend from the Canadian border (line 10) to below 

 Cape San Lucas, Baja California (line 157) . Stations were 

 established on the basis of a perpendicular to line 80 (off Pt. 

 Conception) at a point designated as station 60. Stations were 

 plotted seaward and shoreward from station 60 on each line. 

 Cardinal CalCOFI lines (those ending in "0") are 120 miles apart 

 and usually bracket two ordinal lines (ending in "3" or "7") , so 

 that lines are 40 miles apart over most of the pattern. Cardinal 

 stations are 40 miles apart and typically these are separated by 

 a station number ending in "5" so that stations are 20 miles 

 apart out to station 90 on most lines. Stations are placed at 

 closer intervals near the coast and islands to accommodate these 

 features (see Kramer et al., 1972 for further details). 



