not yet possible to tell with certainty which schools will take the bait 

 and what sorts of schools will noto On the basis of long years of experience 

 and study some general predictions can be made, but the problem must wait 

 for further investigation. In the first place there is no scientific 

 standard in terms of so many fish caught per minute to determine what is 

 to be considered a good-biting school and what is noto Mr. Suehiro of 

 the Fisheries Experiment Station has indicated the following standard for 

 determining whether a school takes the bait well or badl/o 



How well the fish bite is shown in terms of fish taken per man in 100 

 minutes, a figure which is represented by Q. The number of fish caught is 

 b, and the elapsed time in minutes is t, while the number of hooks fished 

 is f „ The formula is 



Q 



b_ 

 tf 



Q ^ 16 means poor biting 

 Q ^17 means good biting 



This means that if one man in 100 minutes hooks 16 or fewer fishj the 

 school is not biting well, and if he hooks 17 or more it is a good-biting 

 schoolo 



If we apply this formula to the actual operations of skipjack boats, 

 we get the following conclusicnSo Skipjack schools in the open ocean 

 generally bite well, and island skipjack generally bite badly. JVhen 

 schools which bite poorly turn up in the open sea it is usually in compara- 

 tively deep water„ The reason for this is explained as being related to 

 the supply of natural food„ 



(The relationship between season, weather, and time and the way the fish 

 bite) 



In the beginning of the skipjack season the fishing grounds are for 

 the most part around islands and reefSo Consequently the fish do not 

 generally bite well because of the abundance of natural food. Toward 

 the end of tha season in the autumn the schools are migrating in the open 

 sea and the fish bite well because they lack natural food. 



Table k Relation of Weather to Biting 



Clear Cloudy Rain 



Fog 



bit well 



bit poorly 



105 

 8A 



20 

 16 



12 



75 



K 

 25 



U 

 100 





 



53 



