Juanico, Baja California (lines 80-137) was sampled more 

 consistently and was surveyed on all 11 cruises. The area off 

 southern Baja California (lines 140-150) was surveyed only once 

 (February) . Offshore coverage was not as extensive as in 1951 

 and occasionally reached station 110 (approximately 250 miles 

 offshore) only on lines 60 and 80. Station 90 was the most 

 seaward station sampled over most of the pattern. Offshore 

 coverage was greatest from January to July and diminished during 

 later cruises. 



Seven vessels were employed on these cruises: the Black 

 Douglas of NMFS; the Crest, Horizon, Paolina T, Spencer F. Baird , 

 and E. W. Scripps of SIO; and the Yellowfin of CDFG. Two to four 

 vessels participated on each cruise with three being the usual 

 number. The Crest was used on all cruises except 52 05 and the 

 Black Douglas on all but 5207, 5209, and 5210. The other five 

 vessels participated on a total of 14 cruises (Ahlstrom, 1954) . 



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 obligue 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 



1 CalC0FI lines (Figure 13) 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 4 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) . 



