reflected in Figures 2-9 and in their data reports (Univ. of 

 Calif., SIO, 1984a-d; 1985).'' 



Two vessels were employed on 1984 survey cruises: the David 

 Starr Jordan of NMFS, and the New Horizon of SIO. Both vessels 

 participated in Cruises 8401, 8404, 8407 and 8410. Cruises 8402 

 and 8406 were conducted on the New Horizon and Cruises 8403 and 

 8405 on the David Starr Jordan. (Univ. of Calif., SIO, 1984 a-d; 

 1985) . 



SAMPLING GEAR AND METHODS 



In 1978, the standard l-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 to 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 side is used for other purposes; the mesh 

 size is either 0.505 mm or 0.333 mm depending on requirements. The 

 cod end of each net is constructed of 0.333 mm mesh. 



The standard tow in 1984 was an oblique haul to ca. 210 m 

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

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

 over the vertical range of most ichthyoplankters. Hauls were made 

 at a ship speed of 1.5-2.0 knots and were initiated by clamping the 



^CalCOFI lines (Figure 9) 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). 



