abundance during this survey: a deep-sea 

 smelt (Leuroglossus stilbius) and a lanternfish 

 (Larrpanyctus mexicanus). The report also re- 

 cords the plankton volumes at all the stations 

 on the survey. Plankton volumes are reported 

 annually by this laboratory (Staff, South Pacific 

 Fishery Investigations, 1952 through 1956; 

 Thrailkill, 1957, 1959, 1961); but the plankton 

 data for this special cruise have not been re- 

 ported previously. 



SURVEY DESIGN 



The survey was designed with the following 

 objectives: First, to determine short-period 

 (1-day) time changes in distribution and num- 

 bers of planktonic organisms, particularly 

 sardine eggs and larvae. A close-spaced 

 grid (gridiron) in a 16-mile square of 25 "grid 

 stations" (stations 4 miles apart) was estab- 

 lished south of Punta Eugenia, Baja California 

 (fig, 1).* This square represented a statistical 

 area of 400 square miles (20 miles to a side), 

 one-fourth of that assigned to a station (stations 

 40 miles apart) on the regular CalCOFI pat- 

 tern. Second, to observe the hydrographic 

 and biological changes at a fixed point. An 

 "anchor station" marked by a fixed buoy 

 was placed at grid-station 3, which is also 

 the regular CalCOFI station 123.40. Third, to 

 observe a single water mass, its movements 

 and its constituents. A "drogue station" was 

 established with a 10-meter drogue attached 

 to a buoy. Its position was determined by 

 currents at that level, and observations at 

 times designated for stations were made at 

 the buoy wherever it was found. 



METHODS OF SAMPLING 



The survey was made April 18-23 by the 

 research vessels the Black Douglas of the Bu- 

 reau of Commercial Fisheries and the Crest 

 and Horizon of the Scripps Institution of Ocean- 

 ography. The Black Douglas and the Crest al- 

 ternated on the grid pattern and anchor station, 

 the former covering the pattern on the first, 

 third, and fifth days. The Horizon sampled at 



iThe grid location was determined by two consecutive 

 surveys of the CalCOFI pattern of f central Baja California 

 during late March and early April. Final observations on 

 the last cruise were taken only 2 days before the survey 

 began. 



the drogue stations for the full time of the 

 investigation. 



Hydrographic and biological observations 

 and collections followed the standard proce- 

 dure of the CalCOFI cruises (Ahlstrom, 1952). 

 At grid stations these included one 200-meter 

 net tow for plankton, one 10-meter hydro- 

 graphic cast for temperature and salinity, 

 one 900-foot bathythermograph (BT) cast, and 

 observations of meterological data. Drogue 

 and anchor stations were made every 4 hours. 

 These observations and collections were the 

 same as those of the grid stations, but with 

 standard hydrographic casts to 600 meters. 

 Additional data from the drogue stations in- 

 cluded Dacteriological samples collected with 

 Johnson-ZoBell (J-Z) bottles on the hydro- 

 graphic casts. The drogue ship also conducted 

 current observations (GEK) in the intervals 

 between stations. Station data are shown in 

 table 1. 



The 25 stations on the grid covered on the 

 first day will be referred to as Grid I (GI-1 to 

 GI-25), those of the next day. Grid II (GII-1 to 

 GII-25), etc., for a total of 125 stations during 

 the 5-day survey. During the same period, 30 

 drogue stations (D-1 to D-30) and 30 anchor 

 stations (A-1 to A-30) were occupied. 



The 10-meter drogue drifted in a southerly 

 current for about 75 nautical miles from its 

 northernmost station, D-2 (fig, 1). 



The anchor-station buoy broke loose after 

 the first six observations. This station was 

 then maintained by navigation, placing most 

 of the following observations within 2 or 3 

 miles of the original position. An error in 

 navigation placed the last six stations about 

 7 miles south of the original position (table 1). 



SARDINE EGGS 



Sardine eggs, listed by age in days (as 

 described by Ahlstrom, 1943), are reported 

 as numbers of normal eggs and total number 

 of eggs (table 2). The totals in excess of the 

 numbers of normal eggs include abnormal 

 eggs that had stunted, discolored, and mis- 

 shapen embryos. Unclassified eggs are those 

 too deteriorated for aging. 



