On the Hatching of Herring Ova in Deep Water. 49 



during the last two years — an enormous number of exceed- 

 ingly small herring have been captured, not only off the 

 Scottish coast during the autumn, but off the English coast 

 during the winter. Owing to the markets being flooded with 

 large quantities of small, immature fish, the fishery industry 

 has to a great extent been paralysed. The cause of this is 

 undoubtedly largely due to the fishermen using small meshed 

 nets, which, while they fail to " mesh " the large fish, capture 

 large numbers of small, often immature fish that are scarcely 

 fit for food. There is every reason to believe that the 

 present unsatisfactory state of the herring fishery might soon 

 disappear were the fishermen and curers to arrange to use nets 

 with a mesh measuring at least an inch from knot to knot. 



A matter of even more vital importance than the size of 

 the fish captured is, will the offshore shoals disappear or 

 diminish (as has been the case with the inshore shoals) if 

 we annually invade them with our large fishing fleets ? This 

 will, to a great extent, depend upon whether the herring 

 are able to reproduce themselves without visiting the inshore 

 spawning banks ; and granting this to be possible, whether 

 they will select spawning grounds sufficiently near our shores 

 to render their capture a profitable enterprise for our fisher- 

 men. That the continued success of the herring fishing, to a 

 great extent, depends on these two conditions, will be at once 

 evident, if we consider under what circumstances the capture 

 of large numbers is rendered possible. It is not sufficient 

 that herring exist in great numbers around the coast ; what 

 is necessary is that they should be found in large shoals in 

 certain limited areas. It seems that herring only congregate 

 in large numbers over limited areas during the spawning 

 season. A remarkable fact is that immature as well as 

 mature fish visit the spawning ground. The mature fish, led 

 by their spawning instinct, seek a suitable bank, probably 

 the one where they first saw the light, on which to deposit 

 their eggs ; and the immature forms, because of their gre- 

 garious or other instincts, follow in their train — the mature 

 fish swimming deeper and deeper as the season advances, 

 while the immature keep near the surface, feeding on Cope- 

 pods, Thysanopoda, and other minute pelagic forms. This 



VOL. IX. D 



