Methods of Testing 



In one series of experiments with macaroni and agar preparations the 

 method of testing was similar to that finally adopted with Inedible lures, namely, 

 to establish a control time (to disappearance of fish) and coTint (of fish caiight) 

 after chumming with live bait ceased, and to determine a test time ajid count while 

 chumming the previously live balt-chummed fish with the edible lure. In a second 

 series of experiments direct chtmmdng of the schools with edible lures was at- 

 tempted. When possible, this was follcwed by chiommlng with live bait to see If 

 the school would respond. 



With the other experiments (dead anchovy, herring, etc.) the materials 

 were used as chum In some cases after the tuna had been chummed to the stern with 

 live bait and In others without chumming with live bait. 



Results 



The results of the first series of experiments with macaroni and agar 



preparations are Included In table 5. On comparing the timing and catch under 



control and test conditions, there Is no indication that the edible lures were 

 attractive to the fish. 



The second series of experiments. Involving direct chumming with the 

 edible lures, was undertaken following a suggestion that the skipjack might be 

 temporarily conditioned to feeding on live bait and, for that reason, might not 

 feed on the edible lures when they were subsequently presented. 



Attempts were made to chum ten different schools with edible lures 

 during October and November 1953 with negative or inconclusive results. While at- 

 tempting to chum three skipjack schools and one dolphin school with macaroni and 

 agar preparations, fish were caught on the trolling jigs soon after chunmilng be- 

 gan, but there was no assurance that this was related to the chumming. In all 

 other cases except one, the results were negative. For the most part, the schools 

 were "wild". Of nine tuna schools, one was chummed to the stern of the vessel 

 with difficulty using live bait, two failed to respond to live bait, two disap- 

 peared before live bait could be used, and for the remaining four, no live bait 

 was available. 



The one exception might be described in more detail. A large school 

 of 17- to 25-pound skipjack was chummed in five different passes with one or a 

 combination of the following edible lures: macaroni cooked in skipjack extract 

 and coated with aluminvim, macaroni cooked in skipjack extract but uncoated, maca- 

 roni cooked in water and coated with alvminum, agar cooked in skipjack extract 

 and impregnated with aluminum, macaroni cooked in anchovy extract £uid coated with 

 alumlniim, and cubes (3/4-inch) of skipjack flesh. On each pass the skipjack were 

 attracted to the stern and, in all, 67 of them were caught with pole and jig. 

 Live bait was not used; none was available. However, it was suspected that the 

 school of skipjack was feeding on opelu ( Decapterus ) and that each time the vessel 

 approached the school the opelu sought refuge under it, thus attracting the skip- 

 jack to within reach of the poles. Opelu were spat up by some of the fish which 

 were caught, and were also found in the stomachs. Moreover, some of the fishermen 

 reported having seen the opelu in the water. None of the stomachs which were 

 examined contained edible lures. 



In earlier experiments, after skipjack had been chummed to the stern 

 with anchovy, chumming was stopped, and dead anchovy were thrown to the feeding 

 fish. They exhibited continued feeding activity for a time, but followed the 

 dead fish down as they sank. Attempts to chum skipjack schools with strips of 

 skipjack flesh failed. The strips were cut to include the silvery skin on one 

 side, and were about the same size as the anchovy used as chum. 



17 



