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any rate considerably reduces their chances of living for any length of time. The large 

 sailing trawlers, which bring their plaice to market dead on ice, can in this respect be 

 classed as almost equal to the steam trawlers; those sailing trawlers however, which 

 keep their fish alive in receptacles provided for the purpose, and sell them alive in the 

 markets, i. e., all the German, and part of the Dutch sailing vessels, naturally make 

 shorter hauls, and most of the plaice are brought up alive. A large portion of the 

 small, undersized fish caught are also alive when brought to the surface, but their 

 vitality is often impaired, so that we must also in this case reckon with the death of 

 half or two-thirds of the number returned to the water. The Danish Snurrevaad. with 

 its quite short hauls of about half an hour's duration, is the only implement up to now 

 which provides practically complete protection of the undersized plaice caught therein. 



From this it follows, that the introduction of a legal size-limit for the plaice can, 

 with the present methods of fishing, only afford real protection for the undersized plaice 

 if fixed so high that it can no longer pay the fishermen to work those grounds where 

 the undersized fish are found in greatest numbers. In other words, the trawlers must 

 voluntarily agree to a I'estriction of their fishery, and renounce the working of the 

 young-fish grounds. And they will do so, as soon as the proceeds of their catches 

 there no longer suffice to pay the working expenses , or do not afford sufficient profit. 



V. 

 Size-limits, and tlie restrictions imposed by tliem on the fishery. 



An extremely important point is the question of how high a size-limit should be 

 in order to render trawling unprofitable at those places where the most young, under- 

 sized plaice are caught, and tliis not as regards plaice fishing alone, but the whole yield. 



In order to solve this problem as regards the English fishery, Masterman has 

 carried out careful investigations in the following manner. He calculates, for each indi- 

 vidual ai'ea, fished by English vessels, and chiefly those with which we are here con- 

 cerned, as being richest in young plaice, viz; As, B4, B3, Cs, for each month i) weight 

 and value of all fish taken with the trawl, including the plaice, and 2) what percentage 

 of the weight and value of these trawling catches is represented by such plaice as lie 

 below the lengths of 20, 23, 26 and 29 cm. He thus arrives at the loss in value 

 which the trawlers would suffer if compelled by a legal size-limit to return all plaice 

 under these lengths to the sea unused. It appears, as might be expected, that this 

 loss not only increases in proportion to the height of the size limit, but varies, given 

 an equal size-limit, for the various areas, and in these again according to the different 

 months of the year. The loss is naturally greatest in those areas, such as A. 5 and B4, 

 where the greatest numbers of young undersized plaice are caught by the English ves- 

 sels, and also the smallest fish of other species than the plaice which are otherwise 



