plots (Figures 2-7) . Cruises 8107 and 8108 in this report are 

 considered a single cruise (8107) in the SIO hydrographic data 

 base and are combined in Figure 7. 



Two vessels were employed on these cruises: the David Starr 

 Jordan of NMFS and the New Horizon of SIO. The David Starr 

 Jordan was used on six cruises and the New Horizon on five (Univ. 

 of Calif., SIO, 1985a, b). 



After 1969, CalCOFI surveys were made on a triennial basis. 

 These began in 1972 and continued every 3 years (1975, 1978, 

 1981, 1984) until 1985 when annual surveys were resumed. 



SAMPLING GEAR AND METHODS 



In 1978, the standard 1-m ring net with towing bridle was 

 replaced by a bridle-free "bongo" net. The bongo frame (McGowan 

 and Brown, 1966; Smith and Richardson, 1977) consists of a pair 

 of circular frames connected by a central axle which is 

 horizontal to the towing wire and attached to it by a clamp. The 

 axle is free to rotate so that the mouth openings are vertical 

 during the tow. The standard CalCOFI version of the bongo net 

 has 71 cm diameter frames and net material constructed of nylon 

 mesh. Each net consists of a cylindrical section ca. 146 cm 

 long, a truncated conical section ca. 161 cm long, and a 

 detachable cod end. The starboard net, from which the standard 

 sample is taken, is constructed of 0.505 mm mesh. The sample 

 from the port net is used for other purposes; the mesh size is 

 either 0.505 mm or 0.333 mm mesh depending on requirements. The 

 cod end of each net is constructed of 0.3 33 mm mesh (W. C. Flerx, 

 pers. comm. ) 



The standard tow in 1981 was an oblique haul to ca. 210 m 

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

 a constant amount of water per depth interval (ca. 2m /m of 

 depth) over the vertical range of most ichthyoplankters. Hauls 



CalCOFI lines (Figure 8) 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). 



