54 ABOUT LOBSTERS 



of all wood with metal, the use of various paints or preserva- 

 tives known or felt to be repulsive or poisonous to borers, 

 and finally, the construction of traps with metals or plastics 

 not subject to borer attack. The first of these possible meth- 

 ods was deemed impractical and the third is still in the ex- 

 perimental stage, though with some degree of reasonable re- 

 sults. Therefore, this section deals only with the various 

 wood preservatives readily available or easily compounded. 



Experimental fishing with treated traps was first com- 

 menced on August 11, 1950, and terminated on September 

 24, 1951. During the period a total of 6,869 lobsters was 

 caught. Two thousand, nine hundred and fifty-nine, or 43.1 

 per cent, of these lobsters were caught in the treated traps 

 and 3,910, or 56.9 per cent, in their corresponding untreated 

 controls. 



In order that a reliable index of catchability might be 

 maintained during the experiment, a treated trap was paired 

 with an untreated trap, in order to reduce to a minimum the 

 influence that varying fishing conditions might have upon 

 apparent catchability results. 



Since many commercial lobster fishermen are of the 

 opinion that the treatment of traps would reduce their catch- 

 ability, experimental traps were built by the Department of 

 Sea and Shore Fisheries; and arrangements were made for 

 several fishermen to operate them in conjunction with their 

 own untreated traps. In this way, it was hoped that prac- 

 tical information on the preservative qualities of various 

 treatments and the effect of these treatments on the catch- 

 ability of the traps could be obained. 



These results can be used only to compare the catch- 

 ability of one treatment with the catchability of the cor- 

 responding untreated control traps. The results are: 



In terms of the period covered and the areas fished, it 

 appears that all treatments reduced the catchability of lob- 

 ster traps. 



