138 



Appendices to Thirty -ninth Annual Report 



never, so far as is known, appeared in great numbers. These opposite 

 conditions are sufficiently remarkable to warrant careful inquiry, and in 

 the research work which we are now again conducting in the sea, special 

 attention is being given to the migratory movements of the young 

 adolescent fish.* 



In the Pentland Firth, where within the period of my own experience 

 as many as 8 grilse used to be taken for every salmon, the proportion 

 of grilse has greatly diminished. At the Halladale fishings only 2 grilse 

 for every salmon are reported. At Crosskirk in 1920 there were fewer 

 grilse than salmon, a condition which has only once previously occurred, 

 so far as I am aware, viz. in 1914. Mr Smith, who has carried on the 

 Crosskirk netting for many years, has kindly given me his figures since 

 1910, and the percentages of grilse are as follows : 



1910 . 



. 75-6 



1916 . 



. 52-7 



1911 . 



. 75-7 



1917 . 



. 57-6 



1912 . 



. 72-4 



1918 . 



. 58-3 



1913 . 



. 62-8 



1919 . 



. 68- 



1914 . 



. 46-5 



1920 . 



. 38-2 



1915 . 



. 69-8 







Only at Sandside, further west, does the condition approximate to 

 half the former percentage. Mr Nicol M'Nicol, for Mr Pilkington, sends 

 in the following return : — 



In 1916 .... 1 Salmon to 



1917 

 1918 

 1919 

 1920 



3 Grilse. 



4 „ 



4 „ 



Aberdeen Harbour Commission Fishing. 



I have been favoured with a return from the Aberdeen Harbour 

 Commissioners showing their salmon catch since 1908, the date of the 

 last statement. I give the quinquennial figures for the total number of 

 years available, and separate salmon and grilse. 



Salmon. Grilse. 



. 1874—1878 . . . 6,132 6,234 



1879—1883 . . . 4,872 9,072 



1884—1888 . . . 5,877 11,718 



1889—1893 . . . 7,514 9,346 



1894—1898 . . . 6,160 8,137 



1899—1903 . . . 4,3f7 - 6,157 



1904—1908 . . . 4,141 4,696 



1909—1913 . . . 5,812 4,113 



1914—1918 . ' . 4,782 2,238 



The figures for the two last years are : — 



Salmon. Grilse. 



1919 5,808 5,927 



1920 6,516 2,335 



Pollutions. 



The menace presented by the insidious increase of pollutions has not 

 attracted the attention it requires. District Fishery Boards find them- 



* Vide separate paper. 



