Studies on the Bait in Trolling-V

The fishing effect of five kinds of ground baits to find economical bait instead of salted anchovy lavae which is commonly used for bait in bonit trolling were tested under the procedure comparing the number of catch by using both anchovy lavae and ground bait alter-natively in the sea at five minute's intervals by the boat, 4 tonnage, 16 horse power with two crews. The results are shown as in Table 1 and Figure 2 that small shrimp (Acetes japanicus), herring (Storephorus japonicus) and sand lance (Ammodytes Personates Girad) are comparati-vely good in the fishing for bait, saury bait fluctuated in the fishing and mixed bait anchovy with noodle is a bait of less merit comparing with normal bait. The effect for bait largely depends upon the sinking speed of bait which is cleared as shown in Fig. 1. The examination in the contents of stmach of bonito caught clearly shows that forty percents of fishes eat experimental ground baits and especially in the afternoon twenty percents of fishes eat ordinaly bait given by other commercial boats at the bonito trolling, shown in Tables 3 and 4.