— 30 



We shall return later on to these statistical investigations. In order to 

 proceed as rapidly as possible with the due and proper treatment of the 

 overfishing question, it soon appeared necessary, besides the general investiga- 

 tions of all the species, to select a certain pleuronectid as the object of par- 

 ticular attention. For this purpose, the plaice (Pleuronectes platessa) was 

 chosen, as well on account of its frequent occurrence as by reason of its 

 great economical importance. Especially in the Southern part of the North 

 Sea the plaice is a fish of peculiar importance to the North Sea trawlers, both 

 steam and sail, its intrinsic value rendering it more important to industry 

 than certain other fishes of which the total catch is greater. The estimation 

 in which this fish is held in our markets, the aggregate value and the quanti- 

 ties landed, the anxiety that has been frequently and publicly expressed in 

 regard to the maintenance of its supply, and the number of nations who 

 engage to a large extent in its capture, are all considerations which have made 

 it in a special degree an object of the International Council's investigations. 



The plaice has thus gradually become the object of most intense in- 

 vestigation. Besides the natural history of this fish, attention has also been 

 directed towards the solution of certain special questions concerning its capture, 

 its distribution on the grounds fished in the North Sea, as well as its size at 

 the different seasons of the year and in the different regions of its distribution. 

 Very extensive statistical investigations (by count, measurement, and weight) 

 were thus carried out for a period of several years at the most important 

 landing places for this fish — Grimsby, Geestemünde, Ymuiden, Esbjerg, etc. 

 and an enormous amount of material in facts and figures thus collected. 



What is the size of the plaice found at a certain season of the year in 

 the different parts of the North Sea? What are the quantities landed in the 

 different months ? Are there any places where the smaller sizes are so strongly 

 represented for several months as to render all fishing there unprofitable as 

 soon as the capture of such small fish was forbidden? Can any minimum of 

 size be laid down, which would provide a sufficient protection, without on the 

 other hand allowing the possibility of objection on the ground of rendering 

 all trawling unprofitable and thus impossible? As already stated, these in- 

 vestigations, which have been carried out with perseverance and on an exten- 

 sive scale, taking several years, have provided a great wealth of material. In 

 each of the co-operating countries where the plaice fishery is of importance, 

 an individual report has been drawn up by a specialist, deahng with the most 



