580 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [48J 



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

 thereby in their choice of locality. 



2. Since fishing begun at Islfendingen, the lower part of Sundstrom- 

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

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

 l)lements 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 OstnsBsfjorden 

 and Svolva^r during the fishing there. Many of the net-fishermen floated 

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

 tom, and the catch was generally good in the floated portion, 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. Tlie fishing 

 mentioned in Buksna^sfjorden under " Fishing at the different stations," 

 and also the advent of cod whicli 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 ai)pears best adapted to cod is between 3^ and 4^ degrees. 



The circumstances which disprove the influenceof 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 temiierature 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 

 temi)er<iture 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- 

 sostrummen, though the temperature gradually decreased to If degrees 

 in 20 fathoms 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 

 11th, though the temperature conditions were the same on both days ; so 

 this ap])ears to be no assurance of a permanently good fishery. 



It is shown by 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 oidy 3 to 4 fathoms ])erpendieuhu]y, I conclude that the tem- 

 perature of 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. 



