42 



nEPARTMENT OF THE NATAL SERVICE 



These investigations, besides rendering possible a comparison between the wastage 

 per cent in the two waters, further afford an excellent illustration of what has been 

 mentioned in the foregoing as regards the extent to which the respective numerical 

 value of the different stages depends on time and place of sampling.^ 



Number of cod eggs pr s 

 minutes haut indicated at 

 each station. ^'A-^^ 1915 



rtlLOMCTEO 



GEOGR MILES (KunRrMIll 



Fig. 25. 



By way of illustrating these conditiuns under varying circumstances, I have chosen 

 a section across the Vestfjord, as marked on the chart, and as the surface hauls (1 m. 

 net, 5 min.) give the greatest amount of material, I have employed these only. 



Six stations are noted on the chart, all from April 23 to April 24, 1913, the total 

 number of cod eggs per 5 mins. surface haul being appended in each case. It will be 

 noticed that station 65, on the edge, has a pronounced maximum, with 9,800 eggs in 

 a single haul, after which the number rapidly decreases to either side, as we leave the 

 spot where the principal spawning presumably took place. During the actual investi- 

 gations it was frequently noted that the greatest numbers of eggs were taken on the 

 fishing grounds themselves, where the fish were most densely congregated. The 

 number diminishes gradually right over towards station 61, on reaching which we 

 again find ourselves near the edge. Here we might thus again have expected to find 

 a maximum ; as a matter of fact, however, there was evidently very little spawning, if 

 any, on these grounds. The banks here, by the way, are of very restricted extent, the 

 bottom sloping abruptly down from land to a great depth. 



With regard to the proportion between the different stages at each of these stations, 

 we find the following figures (per cent) : — 



station 64. Station 63. Station 66. Station 63. Station 62. Station 61. 



1 25 6.3 32 30 40 28 



II r.5 30 53 57 30 46 



III 20 7 15 13 30 26 



From this it will be seen that the earliest egg stages are found in the highest 

 proportion at the very places where the total number was greatest; the more advanced 



1 The inve.stigia.tions extejirled tihrooiglhiout t'be whole of the spawning- seaoon, oomprising- alsio 

 both the bank grounls and the greater depths. The same places were, moreover, investigated 

 several times during the season, partly with the closing net, and partly with an ordinary sur- 

 face net. 



