MAYNARD ET AL.: HAWAIIAN MESOPELAGIC MICRONEKTON 







TEMPERATURE iX) 

 10 20 



30 



I— 



Q_ 



LU 

 CD 



Figure l.-Temperature-depth profiles taken by expendable bathythermographs in the sampling area. 



on the University of Hawaii RV Teritu, 29 Sep- 

 tember to 3 October 1972 (Table 1). Sunrise oc- 

 curred at about 0630 h, sunset at 1830. The moon 

 was in its last quarter; on the last day of the cruise 

 it rose at 0330 and set at about 1530. 



All hauls were oblique and sampled primarily 

 during descent. Two types of tows were made: 

 deep tows 0-ca. 1,200 m (Figure 2a) and shallow 

 tows 0-ca. 400 m (Figure 2b). Two deep-tow series 

 (four day tows, five night tows total) were 

 separated by a 24-h shallow-tow series (six day 



tows, six night tows); three twilight tows (no. 180, 

 184, 197) were also made, but the data were not 

 included in computations of mean standing stocks. 

 The two types of tows were designed to 

 complement each other and provide data on diel 

 vertical migrations; the two deep series were in- 

 tended to examine day-to-day catch variability. 

 The sampling depths were based on the results of 

 previous horizontal sampling which indicated that 

 nearly all micronekton resided between 400 and 

 1,200 m during the day. 



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