Table 18. --Analysis of variance of bait return by kind of bait and 

 sea condition, John R. Manning cruise 13 (based on data 

 in table 31) 



The results of the experiment on Manning cruise 14, testing the 

 differences between single-hooked sardine and herring, have been re-examined in 

 the light of changes in the environment (tables 20 and 21). The analysis of vari- 

 ance of bait return (table 20) shows significant differences with sea condition 

 and between kinds of bait. Consideration of sea height appears to have eliminated 

 the interaction noted In the original analysis (table 12). The means in table 20 

 indicate a progressive decrease in the returns of both baits with higher seas. 

 Furthermore, it is to be expected that herring, which come off the hooks more 

 easily than sardine, would be more severely affected by an increase in movement, 

 as is indicated in table 20. 



In addition to bait return, the relative catches on sardine and herring 

 appear to be affected by variations in sea height. In 1 and 2 seas there were 2.7 

 times more sardine than herring retrieved, and this, combined with the identical 

 catches made on the two baits (table 21), suggests that a large part of this 

 higher herring loss occurred during hauling. An examination of the bait return 

 under sea conditions above 2 shows that the difference in bait return was much 

 greater, with 5.3 times as many sardine as herring retrieved. The analysis of the 

 catch made with the two baits under sea conditions above 2 showed a significantly 



20 



