RAPPORTS. XIV: THOMPSON 



30 



Fig. 63. Monthly Mean of North Sea Catch (in 



thousands of cwts.) of Cod landed at English East 



Coast ports by Steam Trawlers, 1906 — 10. 



J- F. M. A. My. Ju. Jy. Au. S. O. N. 



Fig. 64. Monthly Means of North Sea Catch (in 



thousands of cwts.) of Ling landed at English East 



Coast ports by Steam Trawlers, 1906 — 10. 



Fig. 65. Monthly Means of North Sea Catch (in 



thousands of cwts.) of Saithe landed at English East 



Coast ports by Steams Trawlers, 1906 — 10. 



I have further drawn out a curve (fig. 62) 

 exhibiting from month to month the proportion 

 of small and large Haddock in the total catch 

 of that fish. This subject has in part been 

 dealt with already in this Report, but it is so 

 interesting that we may well return to it again 

 in this brief discussion of monthly or seasonal 

 fluctuations. This diagram brings out two im- 

 portant facts. In the first place it shows us 

 that the great preponderance of small Haddock 

 in the total catch, which the statistics for 1906 — 07 

 revealed, and which was discussed in my former 

 Report, was a transitory phenomenon: it con- 

 tinued in modified degree during 1908, but 

 disappeared in succeeding years. The curve 

 for small Haddock is wholly above that Tor 

 large Haddock from the commencement of our 

 period until September 1908; but from the 

 latter date onwards the two curves go up an 

 down in opposite directions, repeatedly inter- 

 secting one another. 



The second point which this diagram in- 

 dicates, is, that on the whole the small had- 

 dock outnumber the large, and vice versa, with a 

 definite periodicity in particular seasons of the 

 year. The small Haddock are at their maxi- 

 mum and the large at their minimum in spring, 



I 1906 I 



J. F.M. A.M.J. Jy. A. S.O.N. DJ 



Fig. 66. Percentage Proportion of Large among the Cod landed at English East Coast ports by Steam Trawlers, 



1906- " 



