— 40 — 



fish as those which constitute the Grimsby "small" plaice are rarely seen in Aberdeen; 

 only occasionally, as in the autumn from 1905 to 1909 do some small steam trawlers 

 fish dense shoals of small plaice in their third and fourth years quite near the East 

 Coast; fish which could be classed as "young fish" or undersized plaice. These small 

 plaice are then designated "extra small". In the second place we see, that the average 

 weight of the plaice in all four of the regions as here defined, is very high, equalled 

 only in the English landings by that of the areas Ci, Bi, D and E. The East 

 Coast Grounds have the lowest average weight: 600 gr. per fish, which corresponds 

 fairly exactly with the average weight obtained by the English measurements for Area 

 Ci — the area which practically corresponds to the region of the East Coast Grounds. 

 On the Southern, or rather South Eastern Grounds, the average is higher, about 700 

 gr. and lies approximately equidistant between the average weights of the English lan- 

 dings from Ci (abt. 530 gr.) and from Bi, D and E (abt. 830 gr.). These Southern 

 Grounds include chiefly the northern parts of the areas C2 and Bi, with small parts of 

 B5 and B4. And correspondingly, the size of the plaice from these waters is consider- 

 ably lower than that of the fish from the Dogger Bank. The Middle and Northern 

 Grounds have the highest average weight of nearly 900 gr. These grounds include the 

 areas D2, Ds, E, F and G; the English plaice from these areas are however smaller 

 on an average, probably owing to the fact that the Scottish catches are generally taken 

 in more northerly waters than the English hauls. 



Although it is not yet possible to satisfactorily apportion the Scottish landings 

 from the North Sea to the various international areas, we can yet state with certainty 

 that the composition of these is similar to that of the English landings from the northern 

 North Sea with the particular modification however that the Scottish plaice are somewhat 

 larger still than the English. 



Thirdly, we see from the table, that the composition of the Scottish landings ot 

 plaice is mainly determined by the Aberdeen market-class "medium". This class includes 

 plaice of from 23 to 70 cm. in length, having an average weight of abt. 760 gr. and 

 amounts, in these four regions alone, to about 72 "/o to 88 7o of the weight, and 74 7o 

 to 92 "/o of the number. This determining influence of the "medium" class is further 

 shown by the fact that the average weight of the total landings of plaice from the 

 North Sea in Aberdeen is almost the same (abt. 770 gr.) as that of the "medium" 

 class, (760 gr.). According to the Aberdeen market measurements, the median 

 of the "medium" class is at about 41 cm., and. as the total landings from the North 

 Sea show abt. 78 "/o medium, 5 "/o large and 17 % small, i. e. more small than large, 

 the median of the total landings must be reckoned at something under 41 cm., probably 

 about 38 cm. Such a median we find in the English landings approximately from the 

 areas Bi and D. This permits us perhaps to suppose, that the total landings from the 

 North Sea in Aberdeen are similar in composition to those of the areas Bi and D. 

 Thus the number of "undersized" plaice, under 25 cm. would not exceed 5 °/o at the 

 outside, probably not more than i "/o or 2 "/a and that of the "small" plaice, under 

 29 cm. probably only 4 "/o or 6 7o of the total quantity. 



It is thus clear, that the question of the destruction of young undersized plaice and 

 protective measures to prevent same are is of no importance as regards the Scottish 

 fishery when compared with the fishery in the southern North Sea. 



