_ 29 — JOH. H JORT and C. G. JOH. PETERSEN 



island of Sörö (West Finmark) ; also, that in the whole Barents Sea only single cod eggs were 

 spawned (in some fjords of Mnmark). From Sörö to the North Sea the cod spawns, however, 

 on suitable spots and partly on the steep coast declivity, partly on the banks. 



Through numerous investigations in the years 1902 — 1904, all the banks of the Norwegian 

 coastal sea have now been systematically studied, so that we have at present a view over all 

 the larger spawning places of this sea; this is of importance in two ways. Firstly, the 

 region where this economically important fish occurs at the spawning time, has been sharply 

 determined geographically; and secondly, various new and important places for the fishery have 

 been demonstrated. As an account of these would carry us too far in this brief statement, we 

 shall only describe here the conditions on some small specially characteristic and typical banks. 



The greatest cod fisheries in Norway take place on the stretch from and at Lofoten to 

 Tromse. Near to the land here, there is a series of banks lying in depths under 90 m. and 

 indicated on the accompanying Chart (Fig. 4) by Roman figures. They are, as the Chart shows, 

 separated from one another by channels not exceeding 300 m. deep. When the spawning time ap- 

 proaches the cod collect on these small banks exclusively. In different years, the appearance of the 

 shoals may vary somewhat, both as regards time as depth, but it holds good as a rule, that 

 they collect on the slopes of the small banks towards the channel and that they gradually 

 make for the edge of the banks in order to spawn. The fish shoals are thus crowded to- 

 gether on a small space, a factor of importance for the fertilisation of the eggs. As not only 

 the masses of fish but also the eggs floating on the surface of the water are thus concen- 

 trated on a very limited ground, it was possible to find the spawning fish-swarms by this 

 means so that the quantity of the eggs, in the entire water to the surface, was investigated. 



For example, on the region represented on the accompanying charts, the following quantities 

 of eggs were taken during April 1901 in a horizontal haul of 5 minutes duration with a net 

 of 1 m. diameter: 



On Malangs ground, bank 1 8470 and 3565 eggs 



In the channel between banks I and 11 10 — 



On the bank II 3636 — 



In the channel between banks 11 and III 170 — 



On bank III 957 — 



On bank IV 2333 — 



On the slope of the bank towards the depths of the Norwegian Sea 83 — 



Beyond the coastal banks in a great number of hauls — 



This experience, that the region of the floating eggs is so restricted during the spawning 

 of the cod, led to comprehensive fishery experiments to determine likewise the occurrence of 

 the adult cod. This appeared the more important, as previously, only banks II and VI had 

 been fished, whereas pra,ctical fishery experiments had never been made on banks I, III, 

 IV and V. 



In agreement with the distribution of the pelagic eggs, the fishery experiments showed tliat 

 very large quantities of spawning cod occurred on bank I, the Malangs ground. Thus, the re- 

 search-boat could take as many as 5800 cod on 17,8U0 hooks in one day, and afterwards in 



