680 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [48] 



with last year, it is not improbable that the fish have been influenced 

 thereby in their choice of locality. 



2. Since fishing begun at Isla?ndingen, the lower part of Sundstrom- 

 men, the temperature at 20 and 20 fathoms was 4f degrees. The float- 

 ing implements placed 25 fathoms from the surface, and the bottom im- 

 plements set in 25 fathoms, took plenty of fish, while nets placed on the 

 bottom in 60 to 80 fathoms, where the temperature was six degrees, 

 caught almost nothing. The same thing occurred in Ostufcsfjordeu 

 and SvolviBr during the fishing there. Many of the net-fishermen floated 

 only a portion of their nets, and allowed the rest to remain on the bot- 

 tom, and the catch was generally good in the floated i)ortion, and ex- 

 ceedingly light in the bottom nets. 



3. The excellent fishery at Stamsund and stations farther west at the 

 close of February was associated with a rise in the water temperature, 

 which, from 2.50 at a depth of 35 fathoms on the 21st, increased on the 

 25th to 4.50 in 30 fathoms, and 3.50 in 20 fathoms. The same was true 

 of the good fishing which begun in Ostlofoten March 10. The fishing 

 mentioned in Buksnsesfjorden under " Fishing at the different stations," 

 and also the advent of cod whi(!h was noticed, March 17, between Stam- 

 sund and Skokkelvigoerne, occurred at a time when the warm stratum 

 of water had descended to 20 fathoms from the surface. 



The conclusion which I reach from these observations is, that the tem- 

 perature which appears best adapted to cod is between 3i and 4^ degrees. 



The circumstances which disprove the influence of the temperature of 

 the water are the following : 



1. Since there were some fish in the seines, though in smaller and com- 

 paratively unimportant numbers, it follows that a temperature of 5 to 6 

 degrees is, at all events, not a barrier to the presence of cod. 



2. Although the good fishing westward of Stamsund begun with a 

 temperature of 4 degrees in 30 fathoms, it remained good, and in the 

 early part of March it was even unusually good here as well as at Gem- 

 sostrommen, though the temperature gradually decreased to If degrees 

 in 20 fatiioms and 2 degrees in 35 fathoms — which again seems to indi- 

 cate that comparatively cold water is not prejudicial to the thriving of 

 cod. 



3. The fishing, which was excellent at Sund March 10, was poor on the 

 lltli. though the temperature conditions were the same on both days ; so 

 this appears to be no assurance of a permanently good fishery. 



It is shown l)y the combined observations also that some good fishing 

 has taken place in depths where the water temperature varied from 2 

 to 5 degrees. Since this is the greatest variation which has been ob- 

 served during the winter on the banks, and since the taking capacity of 

 a net is only 3 to 4 fathoms perpendicularly, I conclude that the tem- 

 peratureof the water does not play the role in the fishing that one would 

 suppose, at first consideration, should be ascribed to it. Examinations 

 of the temperature of the cod itself at different depths would have been 

 interesting, but I had no thermometer which was suitable therefor. 



