50 THE AGE AND GROWTH OF SALMON AND TROUT. 



As is well known, Herr Landmark's marking experiments indicated 

 that many fish have a great tendency to return to the river where they were 

 marked, but all the same a fair number may go to other places. On the 

 map of Southern Norway (Fig. 29) I have indicated the tracks followed by 

 those salmon which have been recaptured in the sea elsewhere than in the 

 river mouths or in the fjords leading to those rivers in which they were 

 marked. These are, therefore, the only fish which can give us any indica- 

 tion of where those fish go which do not return to the river in which they 

 were marked (see Fig. 29). 



We see at once from this map that most of the tracks have a noticeable 

 tendency towards the north. I have drawn a line from the place of marking 

 to the place of recapture, and naturally we know nothing further of the 

 wanderings of the fish between these two places. 



Naturally, we cannot draw any sure and final conclusions from this, 

 but taken in connection with what we saw of the age distribution of salmon 

 along the coast, these wanderings are both interesting and instructive. 



That they do take place is an established fact. That they must play 

 a certain part in the remarkable age distribution of the fish along the coast 

 cannot be denied, even if for the present we are not in a position to say 

 precisely what weight we should attach to them. 



In this connection it will also be interesting to compare the distribution 

 of the salmon fisheries along our coasts. For this purpose I have divided 

 up the coast into three divisions : 



1. From the Swedish frontier to Jaederen (to the Stavanger Amt). 



2. From Jaederen to Stat (to the Romsdal Amt). 

 8. From Stat to the Russian frontier. 



For each of these three districts I have put down from the Fishery 

 Inspector's statistics the weight of salmon caught in the years 1880 to 1906 

 in the whole of the fisheries both in the rivers and the sea. In the accom- 

 panying table I have given the results in round figures, together with 

 the proportion between the separate yield from river and sea. 



It is possible that the figures obtained are not strictly comparable, 

 owing to the fact that it is only in recent years that the sea fishing has been 

 developed in the northern districts, whereas river fishing has been going 

 on for a long time. In the same way difficulties arise as to the comparison 

 of the statistics from other parts of Norway.* 



However, if we take the figures as they are our table gives us the 

 following. 



We see that in the south the river fisheries are of much greater 



* For example, we have disregarded the fact that the leasing of rivers for sport 

 fishing, i.e., as opposed to netting or trapping, is much more extensive in the north and 

 west than in the south. 



