116 RATE OF GROWTH OF SOME SEA FISHES 



sequently, as the large fish, were more valuable per pound, their work 

 became less remunerative. Dr. Fulton evidently thinks that a fish 

 ought not to be destroyed before it has spawned at least once, and 

 that if it is sexually mature there can be no harm in capturing it. 

 Thus he would only preserve lemon soles [PI. microcephalus) up to 

 8 inches, while the fishermen wanted, to place the limit at 12 inches. 

 Theoretically I am more in agreement with the fishermen on this 

 point than with Dr. Fulton. It seems to me that the mere fact 

 that a fish at a certain small size is capable of breeding, is not a 

 reason for capturing it if its full-grown size is very much larger. 

 Salmon parr in our rivers are sexually mature, at least the males 

 are when only a few inches long, but their capture is prohibited 

 nevertheless. If it were possible to limit the capture of each sea 

 fish to those above a certain size, I think the limit should be deter- 

 mined by the size of the full-grown fish, and not by the size at 

 which it begins to breed. At the same time the limit should not be 

 fixed below the minimum size of sexually mature individuals. 



However, it is not possible to fix a different limit of size for each 

 species of fish captured by the deep-sea trawlers. The only differ- 

 ences in the smallest sizes caught with a given mesh will be due 

 either to differences in the distribution of the young of the several 

 species, or to diffei-ences in the shape of the fish. Thus a sole, 

 10 inches long, could escape through a mesh say 3 inches square, 

 while a turbot, brill, or dory of the same length could not, because 

 the latter three fish are so much broader than a sole in proportion 

 to their length. All that is practically feasible in the case of the 

 deep-sea trawl is to increase the size of the mesh so as to allow 

 more small fish of whatever kind to escape. 



The destruction of under-sized fish in the neighbourhood of 

 Plymouth may be described under two heads : (1), that which is due 

 to the deep-sea trawlers ; (2), that which is due to inshore fishing. 

 The deep-sea trawlers capture large numbers of under-sized soles, 

 lemon-soles, dorys, dabs, pout, whiting, and gurnard. The dabs are, 

 perhaps, of no great importance, but the young pout and poor-cod 

 [G. liiscus and G. minutus) form an important part of the food of 

 the turbot, as I know from examination of the stomachs of the latter. 

 None of these young fish are of much value in the mai^ket. Some of 

 them are sold separately, and the proceeds are by custom allowed 

 to the crew as perquisites. If the mesh of the trawl were en- 

 larged these small fish would not be caught. The mesh at the 

 cod-end is now 1^ inches square, and at the mouth, 4 inches. I 

 believe that the mesh ought to be not less than 3 inches square at 

 the cod- end, and I think that this change would have the additional 

 advantage of allowing much of the useless material known here as 



