ATLANTIC SALMON 



23 



The fish marked in the Moray Firth (Fig. 

 8), with very few exceptions, were not great 

 travellers; they had apparently completed 

 the major part of their journey and were 

 endeavoring to ascend one or other of the 

 local rivers. Practically all were found 

 again within 50 miles of the place of mark- 

 ing and the great majority within 30 miles. 

 The exceptions amounted to only four out of 

 a total of 256 recaptures and the maximum 

 distance was southwards to the Firth of 

 Forth (250 miles). The stock dealt with 

 may therefore be considered to belong to one 

 or other of the 13 rivers which flow into salt 

 water within 50 miles, and most of them at a 

 considerably shorter distance from the place 

 of marking. 



In another experiment (Fig. 9) further to 

 the north on the east coast of Sutherland, 

 but still in the Moray Firth, the same result 

 was brought out. Here a radius of 40 miles 

 covers all but a very small percentage of the 

 recaptures. "Within this radius are to be 

 found the rivers which were also available to 



the fish of the earlier Moray Firth experi- 

 ment, but from results which I shall mention 

 shortly it is clear that many of the fish be- 

 longed to two rivers (Brora and Helmsdale) 

 situated only a few miles on either side of 

 the netting stations. The only important 

 long journeys were made by one fish which 

 went by the north coast to Lochinver on the 

 west coast and four fish which travelled 

 down the east coast, the extreme southern 

 limit being the Yorkshire shore. 



A still more restricted range of movement 

 was shown by salmon (Fig. 10) marked in 

 1920 close to the mouth of the river Thurso 

 in Thurso Bay near the east end of the north 

 coast. Although, owing to a drought of over 

 three months duration when they could not 

 enter fresh water, they had every opportun- 

 ity of spreading for long distances had they 

 so wished, 59 out of 65 recaptures were made 

 within five miles of the place of marking, 

 and this not because the work was limited 

 to a very short period or because the nets 

 within this area were exceptionally numer- 



Pentland Firth 



Fig. 10. 



