— 33 — KNUT DAHL 



A comparison of tlio columns of July 1905 and September 1905 for tlie Sandnes 

 and St0le Fjords shows that the number of fry has been constantly increasing from 

 July to September 1905. 



A comparison of July and September 1905 in the Sendeledfiord shows that the 

 figures are about equal, but this is, as before mentioned, owing to the seine letting all 

 the small fry pass through the meshes, the seine being in September employed without 

 the cloth in the middle (see page 30). In reality the increase in fry from July to 

 September 1905 has been considerable. 



In order to see if the great difference in the numbers of fry between these two 

 years arises from a difference in temperature and salinity, I have carefully compared 

 the observations made in both years. There was however no difference of any consequence 

 to be found, both years being characterised by warm and comparatively salt water 

 during summer. 



Thus in 1904 I very often saw cod fry in shallow water of 18°— 20°. At night 

 during the first days of September 1904 I very often examined shallow bays in the 

 Sondeledfiord by means of a lantern, which clearly illuminated the bottom. Great 

 numbers of cod fry could then be seen moving about in the warm water (15° — 16° 

 centigrade), which during this time of the year extended down to as low as 15 — 16 

 metres. In 1905 I could only very rarely observe a young cod in this way, although I 

 spent many nights in looking for them during summer. 



In 1905 I also endeavoured to fish for them in deeper water down to 14 fathoms 

 water with an eel hand-seine, but I succeeded in finding none deeper than at 7 fathoms, 

 and even at this depth only one was found outside the zostera quite close to the shore. 



A survey of fig. 13 will show us, that the abundance of fry in September 1904 was 

 also very great. In the Sandnes and St0le Fjords the numbers had somewhat decreased 

 compared with July though not to any great extent. In September 1905 the number 

 of fry pr. haul had I'isen very much compared with the results from July , the figures 

 now approaching the figures of the previous year. The rise was greatest in the St0le 

 fjord, which was examined last of all the fjords in question. 



As regards the values for the Sondeled and Belle fjords the figures obtained in 

 September — October are, as previously remarked no safe standard for the actual occurrence 

 of the fry, the sizes below 6—7 cm. then escaping through the seine. Since the occurrence 

 of these small sizes varies in different years, as previously shown, even the relative 

 value of the figures for the different years gained in these fjords at this season is not 

 to be depended upon. 



A direct comparison is therefore only possible between the S0ndeled and Helle 

 Fjords. The Sandnes and St0le Fjords, which were always examined with a seine taking 

 representative catches, may at this season also be compared with each other, but not 

 with the two above-mentioned fjords. 



If however we survey the facts from these fjords separately, and in 

 each fjord compare the results for September — October 1904 with those 

 for September — October 1905 we find the same peculiar difference between 

 the two years. This applies to the fjords where larvae were liberated 

 in spring as well as to those where no hatching operations whatever 

 were undertaken. 



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