FISHERY BULLETIN: VOL. 73, NO. 2 



Table 11. -Measures of daytime availability of skipjack correlated with day concentrations 

 (ml/l.OOO m') of skipjack forage, zooplankton, and their arithmetic product. All tests were 

 made with the variables transformed to logarithms. Numbers are pairs of observations 

 from which correlation coefficients were calculated. No coefficients were significant. "AH" 

 means all skipjack; "large" means skipjack >45 cm. 



Skipjack Data Forage Zooplankton 



availability Period grouping' (F) (Z) F X Z 



Catch/line-hour All 



Large 



Schools/hour All 



Large 



'A, Numbers to the right of this letter are numbers of 1° X 1° quadrants. For each quad- 

 rant skipjack availability is based on all observations for the day, and F and Z are each 

 based on a single observation made in the quadrant during the day. 



B. Numbers to the right of this letter are numbers of 1° zonal row/s of quadrants with > 2 

 quadrants per row. For each row skipjack availability, F and Z are means of the data for the 

 individual quadrants. 



C. Numbers to the right of this letter are numbers of 2' zonal rows of quadrants. For each 

 row skipjack availability, F and Z are means of the data for the individual quadrants. 



Table 12.-Measures of daytime availability of skipjack correlated with night concentra- 

 tions (ml/1,000 m^) of skipjack forage, zooplankton, and their arithmetic product. All tests 

 were made with the variables transformed to logarithms. Numbers are pairs of observa- 

 tions from which correlation coefficients were calculated. Significant correlations occurred 

 as shown by * (5% level of probability) or ** (1% level) and were positive. "AH" means all 

 skipjack; "large" means skipjack > 45 cm. 



Skipjack Data Forage Zooplankton 



availability Period grouping' (F) (Z) F X Z 



Catch/line-hour All 



Large 



Schools/hour All 



Large 



'A. Numbers to the right of this letter are numbers of night stations, one station per night, 

 at which observations of F and Z were made. F, Z, and F X Z for a night station were paired 

 for correlation purposes with the mean of skipjack availability for the daytime periods im- 

 mediately before and after the night on which the station was occupied, in closely adjacent 

 r X 1° quadrants. 



B. Numbers to the right of this letter are numbers of 2° zonal rows of quadrants and 

 night stations. For each row skipjack availability is the mean of the data for the individual 

 quadrants, and F and Z are the means of the data for the individual night stations. 



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