are present, it is possibly better to close the area completelyo It 

 is therefore necessary to realize if the advantages of closing are ■ 

 outweighed byg 



lo The enormous costs and difficulties connected with 



the efficient closing of an area in the seaj 

 2o the possibility of considerable damage to the coastal 



fishery since most of the area within its reach will 



be closedo 

 3o the chance that through over=population the rate of 



growth in the cloased area will become unfavorably lowo 



The difficulties of controlling the closed area must not be 

 underestimate do The British found when they closed the Moray Firth 

 to trawlerSj, that there were many possibilities for surreptitious 

 fishing in the forbidden areao This was true of a comparatively 

 small and easily guarded areaj certainly a great deal different 

 than, for instance, a long coastal regiono Experiences during the 

 war have undoubtedly produced methods which could be used for the 

 guarding of closed areas, but it may be assumed that it will be a 

 difficult task and especially an expensive oneo 



The objection that the rate of growth would decline seriously 

 must be considered and may perhaps be solved by experiences found 

 during both World Wars when various areas were practically closed 

 to the fisheryo The decline in growth rate may perhaps be limited 

 by allowing seine and line trawl fishing in the closed areas© These 

 techniques are not harmful to the young fish and the older fish would 

 be "culled* so that food again would become available for the young 

 fisho 



bo The Possibility of Throwing Undersi7,ed Fish Back Alive 



Several tests have been made to determine the effect of throwing 

 undersized fish back overboard© 



It appeared from older observations (Masterman, 1908j von Reitzenstein, 

 1908 g Borley, 1909) that several factors influence the living vitality 

 of fish thrown on decko The otter trawl delivers the fish on deck in 

 a worse condition than the beam trawl j longer hauls are worse than 

 short ones I jellyfish or trash in the nets lowers the percentage of 

 living fisho Moreover, the fish deteriorates on deck, especially in 

 warm weather and sunshine o 



The British Fishery Biological Service made extensive tests 

 during 1935 and 1936 to determine if it were possible to keep under=- 

 sized plaice alive after they had been brought on deck by throwing 

 them backo The living vitality was checked in two ways j the fia'h 

 were kept on board in tanks for several hours and were put back 

 after tagging, then reports on the catching of tagged fish were 

 oollectedo 71 percent of the plaice set overboard immediately 

 after hauling remained alive during May© 36 percent of the plaice, 

 which had remained on deck for an hour, remained alive o Roundfish 

 are almost always dead or nearly dead when hauled on decko 



