Figure 2. - -Positions of longline stations 

 occupied by the Charles H. Gilbert cruise 

 30, August 6 - September 26, 1956. 



accompanying bird flocks. In addition to these 

 primary missions, the Gilbert conducted bait 

 surveys around the Marquesas Islands, return- 

 ing to Honolulu with 21 buckets of Marquesan 

 sardines ( Harengu la vittata) for introduction 

 into Hawaiian waters. The Smith returned with 

 a load of potential game fish (1658 specimens) 

 from the island of Moorea, Society Islands, 

 for similar introduction into Hawaiian waters; 

 the latter project being conducted by the 

 Territorial Division of Fish and Game. 



FIELD PROCEDURES 



Oceanography and Meteorology 



bathythermograph trace obtained just prior to 

 occupying a station. Thirteen bottles were 

 used in the 1200-meter casts. On the 3000- 

 meter stations two casts were made, one from 

 the surface to 800 meters (10 bottles) , t he 

 other from 600 to 3000 meters (7 bottles). 



Water samples for oxygen, salinity, 

 and inorganic phosphate determinations were 

 drawn from each bottle. The oxygen samples 

 were analyzed on board using the modified 

 Winkler method; the phosphate (frozen) and 

 chloride samples were returned to the labora- 

 tory at Honolulu for analyses. 



Samples for radioactivity determinations 

 were obtained at the surface and 500 meters at 

 the stations indicated on figure 1. At each of 

 these stations, a 1 5- to 20 -minute phytoplankton 

 tow was taken using a Clarke -Bumpus sampler. 

 Water and phytoplankton samples, as appropri- 

 ate, were shipped to the Central Meteorological 

 Laboratory, Tokyo, Japan, and to the Scripps 

 Institution of Oceanography, LaJolla, California, 

 for analyses. 



V 



NUKUHIVA ,, X 



-8'S 



-9»S 



• SCHOOL SIGHTED, 



• CHUMMED, AND 



A SUCCESSFULLY FISHED 

 X LONGLINE STATION 

 B BAITING 



" ^ - ^ y-'^V^-^^/ '^/W OA 





-IO"S 



I40°W 



The Smith occupied a total of 79 

 oceanographic stations; 67 of these were to 

 1200 meters ' depth and 12 were to 3000 meters. 

 The position of each station is shown in figure 

 1. Nansen bottle spacing in the upper 200 

 meters was determined by the character of the 



Figure 3. --Track chart for Charles H. 

 Gilbert cruise 30 in the vicinity of the 

 Marquesas Islands showing positions 

 of longline stations, area of scouting 

 and live-bait fishing, and positions of 

 baiting sites . 



